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FIELD OF INVENTION
The present invention relates to a menstruation periodic counter which is provided with an indicator of menstruation beginning day and an indicator of conceptive period and other functions.
BACKGROUND OF THE INVENTION
For methods of sensing the conceptive period, known are an Ogino's rhythm method of birth control and a basal bodily temperature method. However, it is troublesome in the former Ogino's method to count a certain period of days, and in the latter method to carefully take the bodily temperatures at determined time for long period of days and keep records of them. In addition, there has never been developed such a menstruation periodic counter of compact size which may indicate functionally values of data obtained from these methods.
SUMMARY OF THE INVENTION
In view of these circumstances, this invention is to provide a menstruation periodic counter which may functionally indicate the menstruation beginning date and the conceptive period.
The invention is concerned with the menstruation periodic counter which is characterized by providing an indicator of a calendar of each month, an indicator of a bodily temperature chart and temperature measuring time, an input switch for receiving numerical values, and an alarm mechanism for sounding at the time set by the input switch as demanded, the calendar indicator indicating, by a cursor, information concerning the days obtained from the data for indicating the bodily temperature chart.
Embodiment of the invention will be explained in reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of one embodiment which embodies the invention into a device of a card shape,
FIG. 2 is a block diagram of one embodiment of a counter by the invention,
FIG. 3 is a flow chart showing an initial routine of the counter shown in FIG. 2,
FIG. 4 is a flow chart showing a bodily temperature measuring routine,
FIG. 5 is a flow chart showing an ovulation day routine,
FIG. 6 (a) and (b) are explanatory views showing indications of the bodily temperatures.
In the drawings, the numeral 1 is a temperature measuring senser, 5 is a micro-processor, 7 is A-D converter, 8 is A-D converter control circuit, 9 is LCD indicator, 10 is LCD drive circuit, and 12 is a piezo-buzzer.
DESCRIPTION OF PREFERRED EMBODIMENTS
The attached drawings illustrate a preferable embodiment of the invention. FIG. 1 is a front view of one embodiment which embodies the invention into a device of a card shape. The numeral 9 is LCD indicator provided with liquid crystal indicating device, which comprises a calendar indicator A showing a calender of each month and an illustrator B showing the basal bodily temperature chart, time, day and the bodily temperature. FIG. 2 is a block diagram of one embodiment of a counter by the invention, and the numeral 1 is a temperature measuring sensor. The sensor may be such a kind which is directly bonded with sensor chip such as a silicon diode chip to a distributing wire board of flexible print of polyimide base, but for realizing a short time counting to be effected by the invention it is preferable to use thermistor in the sensor element. In the illustrated embodiment, three leads for bias electric current are included (for heating the temperature in the senser portion as mentioned later), a connector has three terminals for the three leads. The entire body is flexible to be pushed into a device 2, and on use it is taken out therefrom. The numeral 3 is a sensor heating circuit (sensor drive circuit) which in advance heats appropriately the temperature in the senser for enabling the short time counting. That is, a temperature measuring resistor has the characteristic that the resistance value of the element decreases as the temperature increases and it takes less time for measurement as the difference between ambient temperature of the sensor and the temperature to be measured decreases. Taking these points into consideration, if the element is in advance made electrically conductive up to, e.g., around 30° C. by self-heating, the measuring time is accelerated and it is possible to diminish the measuring time lag by means of the pro-heated ambient temperature. Actually, when a switch 4a disposed on a front face of the device of the card shape is pushed down, a circuit in a switch matrix 4 is formed, and when "thermometer" mode is designated, a micro-processor (MPU) 5 outputs the control signal of the temperature measuring range and moves to the bodily temperature measuring routine. The sensor drive circuit controls the bias electric current such that the sensor chip is rapidly heated up to, e.g., 30° C. The micro-processor 5 starts the temperature measuring monitor by means of the bodily temperature measuring routine program, calculates the temperature increasing rate of the senser, detects values treated stochastically (the bodily temperature of 63% in general), calculates real value (more than 98.5% in general) of the exact bodily temperature, and indicates them on LCD indicator 9. Through these relative treatments, time to be taken for measuring the bodily temperatures is largely decreased and the high precision measurement may be promised.
The numeral 6 is a pre-amplifier which appropriately effects DC amplification (current-voltage conversion amplification) on an analog signal sent from the temperature measuring sensor 1, and inputs it to A-D converter 7. For A-D converter, a double integral type of 8-bit binary output is used in general but others may be of course employed. The numeral 8 is A-D converter control circuit which controls standard voltage of A-D converter 7 and sets the temperature measuring range between 35° C. and 42° C. The output of A-D converter 7 is directly given to the micro-processor 5. The matrix in the switch matrix 4 is formed by the setting switch and the operation switch 4a, and the operation of the switch is read out in the micro-processor 5 by the switch monitor program. For the micro-processor 5, C-MOS -b 4-bit micro-computer may be used, and a drive circuit incorporating type may be also used. Other LCD may be of course used for the indicating element. Outputs from the micro-processor 5 are five systems of LCD indicating digit signal. LCD indicating segment signal, switching digit signal, piezo-buzzering drive signal, and bodily temperature measuring senser control signal. LCD indicator 9 is driven by the segment signal and the digit signal, and is lighted by, e.g., duty cycle of 1/32. LCD indicator 9 is arranged with the calender indicator A for indicating the calender of each month and the illustrator B for showing the basal bodily temperature chart. The illustrator B also may show the time, day, bodily temperature and others. If the digit signal is made 48 conditions and the duty cycle is made 1/50, the illustrator B can show days which change together with the temperature chart. 10 is LCD drive circuit, 11 is a liquid crystal vibrator, and 12 is a piezo-buzzer. A-D converter control circuit 8 controls the standard voltage of A-D converter 7 to cause it to cover the temperature measuring range of 35° C. to 42° C. at the ordinary time of measuring temperature, and to cover any one of ranges of 35.5° C. to 37.5° C. (low temperature period) and 36.5° C. to 38.5° C. (high temperature period) at the time of the basal bodily temperature measurement. That is, if A-D converters of the same analyzing ability are used, the measuring precision is heightened by making narrow the range of measuring the temperatures and therefore the measurement of the basal bodily temperature in the low temperature period discriminated by the Ogino method is carried out in the range between 35.5° C. and 37.5° C., and the measurement of the basal bodily temperature is switched to the range between 36.5° C. and 38.5° C., and carried out there.
A next reference will be made to complementary compensation between an assumption method of ovulating period by the Ogino's counting method and a deciding method of ovulating days by the basal bodily temperature method. For example, assuming that it is January 1st today and the previous menstruation beginning day was December 20 last year, the last ovulating period of the women of the 28 day type-menstruation period is 5 days from December 4th to December 8th, and the ovulating period of this time is assumed as the 5 days from January 1st to 5th in dependence on the Ogino's method. These calculations are made by means of the micro-processor 5 by inputting the data of month and day from the key matrix 4a. The calculated results, i.e., the data of the ovulating period are stored in a memory which is provided with the micro-processor 5 (refer to FIG. 3). Since the ovulating period is assumed on January 1st, and when the basal bodily temperature is measured on that day, the measuring range is set in the range of the low temperature period (35.5° C. to 37.5° C.). If the measured temperature is outside of the determined scope due to the cold-fever or other reasons, linearization is made such that the measured temperature is automatically altered to near values to the assumed value, and stored in the memory. This flow chart is shown in FIG. 4. Similarly, the basal bodily temperature is measured, and when the data of more than 30 days are stored in the memory, the days of actually changing from the low temperature period to the high temperature period, i.e., the ovulating day or days are determined, and the data concerning this day are stored in the memory (refer to FIG. 5.). Subsequently, in dependence on this ovulating day the assumption days of the ovulating period by the Ogino's method are corrected as demanded. This correction is automatically made. When the switch 4a is operated, the basal bodily temperature chart and the menstruation periodic calender are illustrated on LCD indicator 9. On the calendar A maintaining the precision by the complementary compensation method, the conceptive period, the expecting days of a next menstruation beginning and others are illustrated by on-and-off of the cursor. Further, in respect to the basal bodily temperatures measured in the long period, the data of the last two months only are illustrated as the basal bodily temperature chart, and especially for effecting easy observation, an under mentioned treatment is prepared.
The average value of the high temperature period and the average value of the low temperature period are calculated, and the middle value therebetween is obtained and the temperature scale is illustrated (refer to FIG. 6). In FIG. 6(a), H is the average of the high temperature period, L is the average of the low temperature period, and Th is the middle value in order to provide "Th= (H-L)/2+L". On the other hand, with respect to the data of the basal bodily temperature, the difference from the average value is obtained and is indicated as an index. For example, assuming H: 37.0° C. and L: 36.4° C., Th (temperature threshold value)is 36.7° C. and when the data of the basal bodily temperatures in the memory range to be shown is 36.8° C., the indication index is obtained as follows:
36.7-36.8=-0.1 (1)
Having a negative mark, it is the high temperature data (H)
37.0-36.8=0.2 (2)
Having no negative mark, it is below the average (D). That is, 36.8° C. of the basal bodily temperature data is an indicating index HD0.2, and this indication is as a white circle in FIG. 6(b). The data corresponding to the ranges of HU and LD are all H or L and the average value indication (for example, as the 2nd from the left in FIG. 6(b)). This is a rational and obvious indication method which pays attention to the fact that the most importance in the basal bodily temperature method is the repeating pattern of the low temperature period and the high temperature period, and the absolute value (actual temperature) is not so very important.
One of the embodiments according to the invention is incorporated with the piezo-buzzer 12 for the time signal, and when coming to the time of measuring the basal bodily temperature, the piezo-buzzer 12 is driven by tune for the measuring time and the micro-processor moves to the bodily temperature measuring routine. When the data obtained by the complementary compensation method are referred to, the temperature measuring range is devised for the correct measurement, and the measured data are preserved in the memory range of the basal bodily temperature data.
As was mentioned above, the present invention is arranged with the calender illustrator, the measuring time and the indicator of the basal bodily temperature chart on the same surface of the device. The calendar indicator shows through the cursor the next menstruation days obtained from the basal bodily temperature data and the conceptive period. The device of the invention is compact and convenient. If the alarm is furnished for the time of measuring the bodily temperature, the measurement may be speedy. | A menstruation periodic counter is provided with an indicator of a calendar, an indicator of a bodily temperature chart and temperature measuring time, an input switch for receiving numeral values, and an alarm mechanism for sounding at a time set by the input switch, and wherein the calendar indicator indicates through a cursor information concerning the days obtained from the data for indicating the bodily temperature chart. Automatic adjustment of the range sensitivity of the temperature sensor and correction of out-of-range values, based on expected basal bodily temperature period as predicted by the Ogino method is effected by microprocessor. | 0 |
[0001] This is a nonprovisional application claiming priority of the provisional application, Ser. No. 60/191,165 filed Mar. 22, 2000.
FIELD OF THE INVENTION
[0002] This invention relates generally to memorializing the cremation remains of deceased humans or animals. More specifically, the invention pertains to the products or methods that fix the cremation remains in a permanent medium as a statue, ornament, gemstone or the like.
BACKGROUND OF THE INVENTION
[0003] The cremation process involves incineration of a body in the presence of air in a specially designed furnace. Temperatures typically reach up to and above 1000° C. for several hours. During this time water is vaporized and all of the organic elements are oxidized and eliminated. What remains at the completion of the process are primarily broken fragments of bones and teeth, which are usually ground into a fine powder prior to disposal.
[0004] The main inorganic constituent of living bone is hydroxyapatite (Ca 5 (PO 4 )3OH). The calcium and phosphorous endure the high temperature firing and are oxidized in the presence of air. The cremated remains, therefore, are essentially calcium phosphate. The mixture is sometimes referred to as “bone ash.” The fundamental chemical constituents of bone ash (calcium and phosphorous oxides) are, in fact, common raw materials used in the processing of various glass and ceramic materials. This allows for the possibility of forming the cremated remains into a variety of enduring materials, which can become part of a lasting and meaningful memorial to the deceased, and represents a unique alternative to the standard and often uncomfortable practice of retaining the cremation remains indefinitely in an ornamental urn.
[0005] Cremation remains have been memorialized in a permanent fixture form. A personalized pet animal memorial product is disclosed in U.S. Pat. No. 5,016,330. A portion of the cremation remains is mixed with a moldable material such as a plaster composition, a wet ceramic mixture, or a porcelain product mixture. The moldable material is shaped to a designed figure, and the ash is permanently fixed in the shaped form when the moldable material hardens. Similarly, U.S. Pat. No. 6,200,507, discloses cremation remains fixed in a moldable resin material which fills a memorial urn.
[0006] However, these examples of a memorial do not utilize the ceramic and/or glass making properties of compounds comprising the bone ash as in the present invention.
SUMMARY OF THE INVENTION
[0007] The present invention describes the conversion of cremated remains, through the application of heat and the addition of additives, into durable solid objects suitable for placement in a memorial display. The method or process of producing the memorial involves the formation of a vitreous (glassy) phase by firing the bone ash along with additional oxide materials to form a melt with the appropriate chemical composition which is cooled to form a ceramic and/or glassy solid. The material can be formed into the desired shape by casting from the melt and subsequent fabrication techniques such as cutting and polishing.
[0008] The processing of the cremation remains may begin with an initial grinding or milling step to produce a uniform powder. Additives, including a glass forming additive, are combined with the bone ash. Depending on the chemical composition required for the final material, the additive will have raw materials of the appropriate compounds which are mixed with the bone ash to produce a composite powder precursor or mixture. This is accomplished by simultaneously milling the powders together to achieve complete mixing and to reduce the particle size.
[0009] The additives are preferably provided in the form of raw materials in a frit phase, which frit additives are milled in a ball mill to an appropriate mill size, and combined with the bone ash. Utilizing frit additives reduces the temperature at which the mixture of additives and bone ash will melt and react to form glass melt.
[0010] The composite powder is then heated to a predetermined temperature for a resident time to form a melt. The melt is poured into a cast where it hardens. This hardened material is then annealed for a resident time and at a predetermined temperature. After the melt is annealed it is cooled to room temperature and the solid cast can be shaped if necessary by cutting and/or polishing techniques known by one skilled in the art. In addition, after product is shaped it may undergo a tonic transfer treatment that strengthens the cast surface.
DETAILED DESCRIPTION OF THE INVENTION
[0011] The present invention utilizes the glass forming characteristics of phosphorous and calcium contained in cremation remains or bone ash to form a ceramic, glass, or artificial gemstone memorial. The bone ash is first milled to an appropriate particulate size of less than 850 microns. Additives are combined with the bone ash to create a precursor mixture. The additives may be in the form of a powdered frit raw material. If powder additives are used the additives are milled with the bone ash to an appropriate particulate size.
[0012] The raw materials are first treated to form a frit additive using standard procedures known by those skilled in the art. The frit additives are then milled to the appropriate mill size, preferably less than 850 microns. Frit additives are preferred in order to reduce the melting temperature of the combined mixture of bone ash and additives.
[0013] The additives contain oxide materials that are combined with the powdered cremation remains fall into several categories: glass formers, glass modifiers and a flux. Examples of each type of material include, but are not limited to:
[0014] 1. Glass formers: SiO 2 , B 2 O 3 or any other compounds used for generation of ceramic or glass products;
[0015] 2. Glass modifiers: Al 2 O 3 , TiO 2 , ZnO 2 ;
[0016] 3. Flux components: MgO, Na 2 O, K 2 O, Li 2 O.
[0017] It should be understood that the term glass, glass former or glass modifier is not intended to limit the scope of the invention, but may include compounds that form ceramics. Glasses are often considered a subset of ceramics, or even as a purview of ceramics. So the invention is not limited to a glass or artificial gemstone, but may include a ceramic product. The invention is for a solid memorial product formed from a mixture of bone ash and additives.
[0018] The various additives are incorporated depending on the desired properties of the glass to be produced. In addition to these materials, small amounts of other metal oxides may be utilized in the glass batch to impart specific colors to the final material. These include, but are not limited to, Cr 2 O 3 , CuO, CoO, FeO, MnO 2 , and NiO 3 . The amount of colorant used ranges from a few tenths to several percent of the total batch weight
[0019] Further processing of the precursor powder is performed using standard glass forming techniques. The mixture is placed in a refractory crucible and heated in an electric furnace to temperatures of approximately 1300° C.-1500° C. The mixture of bone ash and additives forms a glass melt at these temperatures and maybe homogenized by stirring and/or bubbling of a gas through the melt. For example, mixing agents can be added to the mixture to create a bubbling action. The melt is poured into a shaped mold of graphite or stainless steel and annealed to avoid stress-induced cracking from rapid cooling or crystallization due to slow cooling. The solidified glass blank (a cast) is then formed into the desired shape or size by cutting and polishing.
[0020] Detailed analysis of the ash and preparation of several glass compositions using bone ash as a primary ingredient were performed. These glass compositions were melted, cast and annealed. As bone ash often contains many coarse particles and large bone fragments which are not conducive to a glass melting process, as a coarser particle size could result in less homogeneity in the melt and would lengthen overall processing times. The bone ash is preferably ball milled using cylindrical porcelain milling media to a particle size of less than 850 microns. This particle size is sufficient to obtain a homogeneous mixing of the milled ash and can be incorporated into a subsequent glass melt in a reasonable period of time.
[0021] The composition of bone ash from a horse was determined in order to conduct processing steps Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) were used in order to identify changes in mass and any reactions occurring within a representative sample of the ash, as a function of temperature. It was observed through TGA that approximately a 5% mass loss occurred in the ash from 600° C. to 1425° C. (it should be noted that even at 1425° C. the bone ash did not melt). This mass loss was accompanied by a broad endotherm, as indicated by DTA. This is likely attributed to the loss of CO 2 as the ash is heated.
[0022] In addition, x-ray diffraction was performed on three random samples from the batch of milled bone ash in order to determine the homogeneity and phase composition of the material. There was little to no difference in diffraction patterns between the three random samples, indicating little variance in composition within the milled bone ash. Analysis of the major peaks of the x-ray diffraction data indicated the major components of the ash may include the following phases: calcium carbonate, calcium magnesium carbonate and calcium hydroxyapatite. The composition of bone ash is primarily calcium hydroxyapatite, with minor amounts of magnesium oxide and sodium oxide. In accordance with the x-ray diffraction results and the literature survey, the following was taken as the composition of the bone ash: 56.0 wt % CaO, 41.9 wt % P 2 O 5 , 1.1 wt % MgO and 1.0 wt % Na 2 O. This composition was used as a basis for subsequent glass batch calculations.
[0023] It has been determined that the bone ash was primarily comprised of calcium and phosphate. From the TGA/DTA test analysis, it was apparent that even at 1425° C. the bone ash, by itself, would not melt or form a glassy material. Additives to the bone ash were necessary to lower its melting temperature and assist it in forming a glassy product. Phosphate glasses are not known to be very water durable. They tend to form polymeric chains due to the +5 valence of phosphorus. These chains may be easily “unraveled” when attacked by water. A common technique used to stabilize the structure of phosphate glasses is to add +3 valence cations so that a more durable, tetrahedral (+4 valence) structure is obtained. Components which may be added in order to accomplish this include A 1 2 O 3 and B 2 O 3 . Such compounds are referred to in this disclosure as glass modifiers which are those compounds that may modify the glass composition or charactistics. For example alumina, or aluminum oxide is added to stabilize the phosphorous formed glass.
[0024] The addition of Al 2 O 3 increase the processing/melt temperature, requiring the addition of a flux to decrease the processing temperature. A common raw material suited for this is sodium carbonate (Na 2 CO 3 ), which additive is sodium monoxide as above described.
[0025] As previously noted, the major component of the bone ash is calcium. Calcium, in high amounts, is not very conducive to glass forming. A glass former, such as SiO 2 , would need to be added in order to reduce the overall calcium concentration.
[0026] The initial target composition included the following components: bone ash, plus a frit additive including Al 2 O 3 , Na 2 O, and SiO 2 . The raw material used to add the Al 2 O 3 was aluminum hydroxide (Al(OH) 3 ), and the raw material used to add the Na 2 O was Na 2 CO 3 .Five micron Min-U-Sil was used as the raw material for SiO 2 . The following was the initial target composition for the first glass batch (Glass Batch #1):
Component Raw Material wt % Mol % CaO Bone Ash 16.81 22.42 P 2 O 5 Bone Ash 12.56 6.62 Bone Ash MgO Bone Ash 0.34 0.63 Na 2 O Bone Ash 0.29 — Al 2 O 3 AI(OH) 3 13.81 6.62 Na 2 O Na 2 CO 3 12.26 9.01 Frit Additive SiO 2 SiO 2 43.93 54.70
[0027] The initial attempt was to have the molar ratios of P 2 O 5 and Al 2 O 3 be identical, while satisfying approximately 70mol % glass former (P 2 O 5 , Al 2 O 3 , SiO 2 ) and 30mol % glass modifier (CaO, MgO, Na 2 O). It happens that in this case, 7 parts (wt %) of frit added to 3 parts (wt %) of bone 10 ash would comprise the “glass” composition.
[0028] Tables 1 through 16 show an outline of the sixteen glass compositions evaluated, with heating schedule, annealing schedule and a physical description of the resulting product.
TABLE 1 Glass Batch #1 Oxide RM* Oxide** Oxide Component Raw Material wt % wt % Mol % CaO Bone Ash 16.81 18.65 22.42 P 2 O 5 Bone Ash 12.56 13.94 6.62 Bone Ash MgO Bone Ash 0.34 0.38 0.63 (33.29 wt % bone ash) Na 2 O Bone Ash 0.29 0.32 0.35 Al 2 O 3 Al(OH) 3 13.81 10.01 6.62 Na 2 O Na 2 CO 3 12.26 7.96 8.65 Frit Additive SiO 2 SiO 2 43.93 48.74 54.70 (66.71 wt % frit)
[0029] Frit Composition
Oxide mol % Al 2 O 3 9.46 Na 2 O 12.37 SiO2 78.17
[0030] The material was “charged” into a platinum crucible at 1315° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 20 hours.
[0031] Even after 20 hours at 1315° C., the material did not melt. It was a hard, foamy consistency inappropriate for glass pouring. The temperature of the furnace was increased to 1400° C. for two hours in order to promote melting. Melting did not occur.
[0032] For Glass Batch #2, additional flux (Na2O) and glass former (SiO 2 ) were added to assist in forming of a glass melt.
TABLE 2 Glass Batch #2 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 13.84 15.44 16.48 P 2 O 5 Bone Ash 10.34 11.53 4.86 Bone Ash MgO Bone Ash 0.28 0.31 0.47 (27.55 wt % bone ash) Na 2 O Na 2 CO 3 0.24 0.27 — Al 2 O 3 Al(OH) 3 11.37 8.29 7.45 Na 2 O Na 2 CO 3 15.39 10.04 16.58 Frit Additive SiO 2 SiO 2 48.53 54.13 53.92 (72.45 wt % frit)
[0033] Frit Composition
Oxide mol % Al 2 O 3 9.46 Na 2 O 12.37 SiO 2 78.17
[0034] The material was “melted” in a platinum crucible at 1425° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 12 hours.
[0035] After 12 hours at 1425° C., the material did not melt. It was a 15 hard, foamy consistency inappropriate for glass pouring. The entire crucible plus contents was quenched in room temperature water. The contents of the crucible were extracted and examined. The contents appeared to have a white/greenish hue. The material was opaque and not a glass. It did appear to be uniform throughout.
[0036] Additional glass former (SiO 2 ) was then added in Glass Batch #3 to help promote glass forming.
TABLE 3 Glass Batch #3 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 11.20 12.01 13.84 P 2 O 5 Bone Ash 8.38 8.98 4.09 Bone Ash MgO Bone Ash 0.23 0.24 0.39 (21.44 wt % bone ash) Na 2 O Bone Ash 0.20 0.21 0.22 Al 2 O 3 Al(OH) 3 9.21 6.45 4.09 Na 2 O Na 2 CO 3 8.50 5.33 5.56 Frit Additive SiO 2 SiO 2 62.28 66.77 71.83 (78.56 wt % frit)
[0037] Frit Composition
Oxide mol % Al 2 O 3 5.02 Na 2 O 6.82 SiO 2 88.16
[0038] The material was “melted” in a platinum crucible at 1425° C. in the Deltec high-temperature furnace and allowed to remain in the 15 furnace at this temperature for approximately 6 hours.
[0039] After 6 hours at 1425° C., the material did not melt. It was a hard consistency inappropriate for glass pouring. The entire crucible plus contents was quenched in room temperature water. The contents of the crucible were extracted and examined. The contents appeared to have a white, opaque coloration. The material was not a glass. It did appear to be uniform throughout, however, with no additional coloration.
[0040] Additional flux (Na 2 O) was ten added in Glass Batch #4 to help promote glass forming and reduce the processing temperature.
TABLE 4 Glass Batch #4 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 9.56 10.96 12.59 P 2 O 5 Bone Ash 7.15 8.19 3.72 Bone Ash MgO Bone Ash 0.19 0.22 0.35 (19.56 wt % bone ash) Na 2 O Bone Ash 0.17 0.19 0.20 Al 2 O 3 Al(OH) 3 7.86 5.89 3.72 Na 2 O Na 2 CO 3 24.19 16.22 16.86 Frit Additive SiO 2 SiO 2 50.89 58.34 62.57 (80.44 wt % frit)
[0041] Frit Composition
Oxide mol % Al 2 O 3 4.47 Na 2 O 20.28 SiO 2 75.25
[0042] The material was “melted” in a platinum crucible at 1425° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 12 hours.
[0043] After 12 hours at 1425° C., the material did melt. It was of a viscosity favoring glass pouring. The melt was poured into a graphite mold of the following dimensions (1.30 cm×1.30 cm ×12.0 cm). The cast rod was annealed at 540° C. for 2 hours in the Termolyne box furnace. The cast rod appeared to have white opacity throughout its interior. This could have been due to phase separation.
[0044] Glass Batch #5 had less Al 2 O 3 content in order to lower the overall processing temperature.
TABLE 5 Glass Batch #5 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 9.64 11.01 12.39 P 2 O 5 Bone Ash 7.21 8.23 3.66 Bone Ash MgO Bone Ash 0.20 0.22 0.35 (19.67 wt % bone ash) Na 2 O Bone Ash 0.17 0.20 0.20 Al2O3 Al(OH) 3 1.00 0.74 0.46 Na 2 O Na 2 CO 3 29.27 19.56 19.91 Frit Additive SiO 2 SiO 2 52.53 60.03 63.04 (80.33 wt % frit)
[0045] Frit Composition
Oxide mol % Al 2 O 3 0.55 Na 2 O 23.87 SiO 2 75.58
[0046] The material was “melted” in a platinum crucible at 1400° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 7 hours.
[0047] After 7 hours at 1400° C., the material did melt. It was of a viscosity favoring glass pouring. The melt was poured into a graphite mold of the following dimensions (1.30 cm×1.30 cm×12.0 cm). The cast rod was annealed at 500° C. for 2 hours in the Thermolyne box furnace. The cast rod was transparent/clear through its interior, with an amber hue. The amber hue could be imparted from impurities in the bone ash. In the center of the rod had a very slight “haze,” indicative of possible phase separation.
[0048] Glass Batch #6 had more frit additive in order to move completely out of this phase separation regime.
TABLE 6 Glass Batch #6 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 9.20 10.54 11.84 Bone Ash P 2 O 5 Bone Ash 6.87 7.87 3.49 (18.81 wt % MgO Bone Ash 0.18 0.21 0.33 bone ash) Na 2 O Bone Ash 0.16 0.19 0.19 Al 2 O 3 Al(OH) 3 0.99 0.74 0.46 Frit Additive Na 2 O Na 2 CO 3 29.80 19.97 20.29 (81.19 wt % SiO 2 SiO2 52.79 60.48 63.40 frit)
[0049] Frit Composition
Oxide mol % Al 2 O 3 0.55 Na 2 O 24.11 SiO 2 75.34
[0050] The material was “melted” in a platinum crucible at 1365° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 12 hours.
[0051] After 12 hours at 1365° C., the material did melt. It was of a viscosity favoring glass pouring. The melt was poured into a graphite mold of the following dimensions (1.30 cm×1.30 cm×12.0 cm). The cast rod was annealed at 500° C. for 2 hours in the Thermolyne box furnace. The cast rod was transparent/clear through its interior, with a slight amber/yellow hue. The amber hue could be imparted from impurities in the bone ash. Unlike the previous glass batch, there was no apparent phase separation.
[0052] Glass Batch #7 had a little addition of manganese dioxide in an attempt at “decolonization.”
TABLE 7 Glass Batch #7 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 9.19 10.53 11.83 Bone Ash P 2 O 5 Bone Ash 6.86 7.86 3.49 (21.44 wt % MgO Bone Ash 0.18 0.21 0.33 bone ash) Na 2 O Bone Ash 0.16 0.19 0.19 Al 2 O 3 Al(OH) 3 0.99 0.74 0.46 Frit Additive Na 2 O Na 2 CO 3 29.77 19.94 20.27 (81.21 wt % SiO 2 SiO 2 52.74 60.41 63.35 frit) MnO 2 MnO 2 0.10 0.11 0.08
[0053] Frit Composition
Oxide mol % Al 2 O 3 0.55 Na 2 O 24.09 SiO 2 75.27 MnO 2 0.10
[0054] The material was “melted” in a platinum crucible at 1365° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 7 hours.
[0055] After 7 hours at 1365° C., the material did melt. It was of a viscosity favoring glass pouring. The melt was poured into a graphite mold of the following dimensions (1.30 cm×1.30 cm×12.0 cm). The cast rod was annealed at 500° C. for 2 hours in the Thermolyne box furnace. The cast rod was transparent/clear through its interior, with a slight amber/yellow hue. The amber hue could be imparted from impurities in the bone ash. Unlike the previous glass batch, there was perhaps a little less coloration.
[0056] Glass Batch #8 had the same composition of Glass Batch #6, with the elimination of Al 2 O 3 altogether, in order to lower the processing temperature even further.
TABLE 8 Glass Batch #8 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 9.29 10.62 11.89 Bone Ash P 2 O 5 Bone Ash 6.94 7.93 3.51 (18.95 wt % MgO Bone Ash 0.19 0.21 0.33 bone ash) Na 2 O Bone Ash 0.16 0.19 0.19 Frit Additive Na 2 O Na 2 CO 3 30.10 20.11 20.38 (81.05 wt % SiO 2 SiO 2 53.32 60.93 63.69 frit)
[0057] Frit Composition
Oxide mol % Na 2 O 24.24 SiO 2 75.76
[0058] The material was “melted” in a platinum crucible at 1360° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 15 hours.
[0059] After 15 hours at 1360° C., the material did melt. It was of a viscosity favoring glass pouring. The melt was poured into a graphite mold of the following dimensions (1.30 cm×1.30 cm×12.0 cm). The cast rod was annealed at 500° C. for 2 hours in the Thermolyne box furnace.
[0060] The cast rod was transparent/clear through its interior, with a amber/brownish hue. The amber hue could be imparted from impurities in the bone ash.
[0061] Glass Batch #9 had slightly more bone ash content.
TABLE 9 Glass Batch #9 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 10.13 11.55 12.98 Bone Ash P 2 O 5 BoneAsh 7.57 8.63 3.83 (20.62 wt % MgO Bone Ash 0.20 0.23 0.36 bone ash) Na 2 O Bone Ash 0.18 0.21 0.21 Na 2 O Na 2 CO 3 29.56 19.70 20.03 Frit Additive SiO 2 SiO 2 52.36 59.68 62.59 (79.38 wt % frit)
[0062] Frit Composition
Oxide mol % Na 2 O 24.24 SiO 2 75.76
[0063] The material was “melted” in a platinum crucible at 1360° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 20 hours.
[0064] After 20 hours at 1360° C., the material did melt. It was of a viscosity favoring glass pouring. The melt was poured into a graphite mold of the following dimensions (1.30 cm×1.30 cm×12.0 cm). The cast rod was annealed at 500° C. for 2 hours in the Thermolyne box furnace. The cast rod was transparent/clear through its interior, with a amber/brownish hue. The coloration appeared slightly darker than the rod cast from the previous batch. The amber hue could be imparted from impurities in the bone ash.
[0065] Glass Batch # 10 had even more bone ash content.
TABLE 10 Glass Batch #10 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 12.01 13.61 15.40 Bone Ash P 2 O 5 Bone Ash 8.98 10.18 4.55 (24.29 wt % MgO Bone Ash 0.24 0.27 0.43 bone ash) Na 2 O Bone Ash 0.21 0.23 0.24 Na 2 O Na 2 CO 3 28.35 18.79 19.24 Frit Additive SiO 2 SiO 2 50.22 56.92 60.13 (75.71 wt % frit)
[0066] Frit Composition
Oxide mol % Na 2 O 24.24 SiO 2 75.76
[0067] The material was “melted” in a platinum crucible at 1360° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 20 hours.
[0068] After 20 hours at 1360° C., the material did melt. It was of a viscosity favoring glass pouring. The melt was poured into a graphite mold of the following dimensions (1.30 cm×1.30 cm×12.0 cm). The cast rod was annealed at 500° C. for 2 hours in the Thermolyne box furnace. The cast rod had some opacity (“cloudiness”) within its interior, with a amber/brownish hue.
[0069] Glass Batch #11 had even more bone ash content.
TABLE 11 Glass Batch #11 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 14.95 16.80 19.23 Bone Ash P 2 O 5 Bone Ash 11.18 12.56 5.68 (29.98 wt % MgO Bone Ash 0.30 0.34 0.54 bone ash) Na 2 O Bone Ash 0.26 0.29 0.30 Na 2 O Na 2 CO 3 26.45 17.38 18.00 Frit Additive SiO 2 SiO 2 46.86 52.64 56.25 (70.02 wt % frit)
[0070] Frit Composition
Oxide mol % Na 2 O 24.24 SiO 2 75.76
[0071] The material was “melted” in a platinum crucible at 1360° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 20 hours.
[0072] After 20 hours at 1360° C., the material did melt. It was of a viscosity favoring glass pouring. The melt was poured into a graphite mold of the following dimensions (1.30 cm×1.30 cm×12.0 cm). The cast rod was annealed at 500° C. for 2 hours in the Thermolyne box furnace. The cast rod had much opacity within its interior, with a brownish hue, resulting in a “marble-like” appearance.
[0073] Glass Batch # 12 had even more bone ash content than previously.
TABLE 12 Glass Batch #12 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 17.66 19.63 22.70 Bone Ash P 2 O 5 Bone Ash 13.20 14.66 6.70 (35.04 wt % MgO Bone Ash 0.36 0.40 0.64 bone ash) Na 2 O Bone Ash 0.31 0.34 0.36 Na 2 O Na 2 CO 3 24.13 15.68 16.41 Frit Additive SiO 2 SiO 2 44.34 49.28 53.19 (64.96 wt % frit)
[0074] Frit Composition
Oxide mol % Na 2 O 23.58 SiO 2 76.42
[0075] The material was “melted” in a platinum crucible at 1400° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 20 hours.
[0076] After 20 hours at 1400° C., the material did melt. It was of a viscosity favoring glass pouring. The melt was poured into a graphite mold of the following dimensions (1.30 cm×1.30 cm×12.0 cm). The cast rod was annealed at 500° C. for 2 hours in the Thermolyne box furnace. The cast rod was completely opaque white. It was uncertain whether the material formed a glass at all. The boundaries of glass forming within the silicate-based compositions had been identified.
[0077] Glass Batch #13 will be of a borosilicate composition, in order to investigate its glass forming tendencies and processing characteristics.
TABLE 13 Glass Batch #13 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 15.38 22.52 28.75 Bone Ash P 2 O 5 Bone Ash 11.49 16.83 8.49 (40.19 wt % MgO Bone Ash 0.31 0.45 0.80 bone ash) Na 2 O Bone Ash 0.27 0.39 0.45 B 2 O 3 Na 2 CO 3 72.55 59.81 61.51 Frit Additive (59.81 wt % frit)
[0078] Frit Composition
Oxide mol % B 2 O 3 100.00
[0079] The material was “melted” in a platinum crucible at 1170° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 20 hours.
[0080] After 20 hours at 1170° C., the material did melt. It was of an inhomogeneous viscosity (low viscosity on the surface, high viscosity near the bottom of the crucible). The melt was poured into a graphite mold of the following dimensions (1.30 cm×1.30 cm×12.0 cm). The cast rod was annealed at 500° C. for 2 hours in the Thermolyne box furnace. The cast rod was completely opaque, with a slight yellow coloration. It was uncertain whether the material formed a glass at all.
[0081] Glass Batch #14 included the addition of SiO 2 to promote homogeneity and glass forming.
TABLE 14 Glass Batch #14 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 14.43 18.78 22.63 Bone Ash P 2 O 5 Bone Ash 10.78 14.03 6.68 (33.51 wt % MgO Bone Ash 0.29 0.38 0.63 bone ash) Na 2 O Bone Ash 0.25 0.33 0.36 Na 2 O Na 2 CO 2 10.95 8.34 9.09 Frit Additive SiO 2 SiO 2 20.70 26.94 30.30 (66.49 wt % B 2 O 3 Na 2 CO 3 42.60 31.21 30.30 frit)
[0082] Frit Composition
Oxide mol % Na 2 O 13.04 SiO 2 43.48 B 2 O 3 43.48
[0083] The material was “melted” in a platinum crucible at 1330° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 20 hours.
[0084] After 20 hours at 1330° C., the material did melt. It was of a viscosity appropriate for glass pouring. The melt was poured into a graphite mold of the following dimensions (1.30 cm×1.30 cm×12.0 cm).
[0085] The cast rod was annealed at 500° C. for 2 hours in the Thermolyne box furnace. The cast rod was completely opaque, uniformly white throughout. The opacity could be due to phase separation, as the surface of the cast rod appeared “glossy.”
[0086] Glass Batch #15 was the same as Glass Batch #8.
Glass Batch #15 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 9.29 10.62 11.89 Bone Ash P 2 O 5 Bone Ash 6.94 7.93 3.51 (18.95 wt % MgO Bone Ash 0.19 0.21 0.33 bone ash) Na 2 O Bone Ash 0.16 0.19 0.19 Na 2 O Na 2 CO 2 30.10 20.11 20.38 Frit Additive SiO 2 SiO 2 53.32 60.93 63.69 (81.05 wt % frit)
[0087] Frit Composition
Oxide mol % Na 2 O 24.24 SiO 2 75.76
[0088] The material was “melted” in a platinum crucible at 1360° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 16 hours.
[0089] After 16 hours at 1360° C., the material did melt. It was of a viscosity favoring glass pouring. The melt was poured into a graphite mold of the following dimensions (1.30 cm×1.30 cm×12.0 cm). The cast rod was annealed at 500° C. for 2 hours in the Thermolyne box furnace. The cast rod was transparent/clear through its interior, with a amber/brownish hue. The amber hue could be imparted from impurities in the bone ash.
[0090] Glass Batch #16 was of the same composition of Glass Batch #8, except that cremated dog remains were used as the ash raw material rather than cremated horse remains as in Glass Batch #8. This allowed for some visual comparisons between these two glasses.
TABLE 16 Glass Batch #16 Oxide Raw RM* Oxide** Oxide Component Material wt % wt % mol % CaO Bone Ash 9.29 10.62 11.89 Bone Ash P 2 O 5 Bone Ash 6.94 7.93 3.51 (18.95 wt % MgO Bone Ash 0.19 0.21 0.33 bone ash) Na 2 O Bone Ash 0.16 0.19 0.19 Na 2 O Na 2 CO 2 30.10 20.11 20.38 Frit Additive SiO 2 SiO 2 53.32 60.93 63.69 (81.05 wt % frit)
[0091] Frit Composition
Oxide mol % Na 2 O 24.24 SiO 2 75.76
[0092] The material was “melted” in a platinum crucible at 1360° C. in the Deltec high-temperature furnace and allowed to remain in the furnace at this temperature for approximately 20 hours.
[0093] After 20 hours at 1360° C., the material did melt. It was of a viscosity favoring glass pouring. The melt was poured into a graphite mold of the following dimensions (1.30 cm×1.30 cm×12.0 cm). The cast rod was annealed at 500° C. for 2 hours in the Thermolyne box furnace. The cast rod was transparent/clear through its interior, with white opaque cords, or ribbons, running through the interior. These could be regions of phase separation or discolorations imparted by impurities in the ash.
[0094] It can be understood from the foregoing that different combinations of the additives and bone ash created casts or molded forms of varying characteristics and changed parameters of the operating procedure. The composition of the bone ash in terms of the molar percentage of its constituent compounds obviously remained fairly constant, but the change of the weight percentage of the bone ash to that of the percent by weight to the additives effected the final product. The less bone ash used resulted in more clear or transparent glass product, while increased amounts of bone ash used resulted in less clear or more opaque product. In addition, increased amounts of bone ash resulted in higher operating (melting) temperatures at longer resident times.
[0095] Similarly, one may surmise that change the molar percentages of the additives with respect to one another changed the product characteristics and operating parameters. The reduction of the glass modifier aluminum oxide resulted in more transparent product, but increased the melting temperature. Consequently, additional flux may have been required. In addition, the durability of the product may have been compromised.
[0096] Target glass compositions were prepared and glass products of unique coloration were melted and cast. The hardnesses of these glass products were statistically similar and were approximately 94% that of a standard flat window glass. Some optimization of composition may be performed in order to increase these hardness values. All of the glass products containing bone ash which were fabricated underwent a 12 hour water durability test at 90° C. It should be noted that this was an aggressive durability test. It was decided to make this comparison to a flat glass standard due to the lack of any industry standard in evaluating the extent of corrosion in glasses. The addition of other components to these glasses, namely an increase in Al 2 O 3 and decrease in Na 2 O, may result in an increase in durability. It must be understood that such an approach would very likely increase the processing temperature of these glasses.
[0097] Another approach in optimizing hardness and durability would be to decrease the ash content in these glasses even further. In addition treatments are known and used to strengthen glass objects. One such procedure involves an ionic exchange on the surface of the cast. The cast or molded form is placed in a salt solution which is heated to 300° C.-500° C. An ionic transfer takes place between larger ions replacing smaller ions on the cast surface which strengthens the cast surface. This is a process which is used in strengthening lenses for glasses and know by those skilled in the art.
[0098] While the preferred embodiments of the present invention have been shown and described herein in the context of using glass formers or glass modifiers, in combination with bone ash, it will be obvious that such embodiments are provided by way of example only and not of limitation. Numerous variations, changes and substitutions will occur to those skilled in the art without departing from the invention herein. Accordingly, it is intended that the invention be limited only by the spirit and scope of the appended claims. | A memorial product generated from the cremation remains of a deceased human or animal whereby a predetermined amount of bone ash is combined with a predetermined amount of a glass forming additive. In addition, a glass modifier may be added to enchance the durability of the final solid product. A flux may also be added to reduce the melting temperature of the mixture. These additives are combined with bone ash and milled to a desired particulate size to form a powder mixture. The mixture is heated to a melting temperature for a resident time to form a glass melt which is then poured into a mold. The cast or molded form is annealed for a resident time at a predetermined temperature to avoid stress fracture or crystalization from cooling too quickly or slowly. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention concerns reactive iridoid derivatives of the general formula I ##STR2## wherein R is a hydrogen atom, an alkyl group with 1 to 5 carbon atoms, an acyl group with 2 to 6 C atoms, an unsubstituted aralkyl group with 7 to 12 C atoms, a methanesulfonyl- or toluenesulfonyl group, a benzoyl-, a preferably para-substituted nitrobenzoyl- or chlorobenzoyl group or a tetrahydropyranyl group.
2. Description of the Prior Art
The iridoids are a group of natural substances whose common structural feature consists of the cyclopentanpyran ring system: ##STR3## The iridoids occurring in nature are generally present in the form of glycosides, wherein their sugar is linked with the C 1 -atom of the iridoid. An iridoid glycoside which can be isolated easily from the drug Picrorhiza kurrooa, Royle (Indian Gentian, family Scrophulariaceae) is the Catalpol of formula II ##STR4## which is characterized by the epoxide ring between C 7 and C 8 and is present as 1-β-D-glucopyranoside.
A survey of the iridoid glycosides and their isolation is to be found in the article of O. Sticher and U.Junod-Busch in: Pharm.Acta Helv. 50, pp. 127-144 (1975).
It is the aim of this invention to provide the compounds of general formula I and the simplest possible procedure for their manufacture, thus also providing a new and simple access to reactive iridoid derivatives, in order to open up in this manner new ways of synthesizing pharmacologically effective classes of natural substances, prostanoids in particular.
SUMMARY OF THE INVENTION
This aim is achieved by the preparation of the compounds of the invention, the process according to the invention and the application of these compounds resulting from the invention.
The compounds 7-hydroxy-3-oxa-bicyclo[4.3.0]non-1-en -9-one and 7-acetoxy-3-oxa-bicyclo[4.3.0]non-1-en -9-one, which may be present on account of their asymmetrical carbon atoms C 6 and C 7 in the form of their optically active(+)- and (-)-diastereomeres, or in the form of their racemates, are particularly preferred in the case of the invention.
With regard to the nomenclature of the compounds of the invention, attention must be given to the fact that the numbering of the ring system differs according to whether it is designated as an iridoid derivative or a bicyclo[4.3.0]nonenone: ##STR5##
The compounds of General Formula I according to the invention can be manufactured from natural Catalpol (1a) without timeconsuming separation processes in four or five reaction steps according to the following reaction scheme: ##STR6##
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the first reaction step, Catalpol is acylated (O-acylation) with the anhydride of a carbonic acid possessing 2 to 6 carbon atoms, in anhydrous pyridine at ambient temperature to obtain hexa-acyl-catalpol (1b). In this process, the four free hydroxyl groups of the β-D-glucopyranose are also O-acylated.
In the second reaction step, the resultant hexaacyl-catalpol (1b) is quantitatively converted by catalytic hydrogenation to the corresponding saturated compound, i.e. hexaacyl-dihydrocatalpol (2b).
The hexaacyl-dihydrocatalpol (2b) is then, in the third reaction step, converted by reaction with lithium alanate in a dipolar, aprotic solvent, preferably in absolute tetrahydrofurane, whereby the epoxide ring is split regio-selectively and all acyl residues are once more split off, thus producing 6,8-dihydroxy-8-hydroxymethyl-1-iridanyl-1'-β-D-glucopyranoside (3a).
In the fourth reaction step, the compound (3a) is oxidized with an oxidizing agent known for splitting glycols, preferably with periodic acid or one of its salts, especially with sodium periodate, or with lead tetraacetate, preferably in an aqueous solution, where after the reaction solution is saturated with a weak base, for example aqueous solution of hydrogen carbonate. The final step in the procedure is remarkable in that the oxidation, for example with sodium periodate in the case of the iridoid glucosides, normally causes the glucoside bond--contrary to the other glucosides--to be split, so that the aglycone forms are also obtained apart from the carbonic acids produced from the glucose. When compared with the known acid-catalyzed glucoside splitting, this has the advantage that the aglycones can be isolated from the weak alkaline solution using a suitable base directly following saturation, and do not have to be separated from the glucose otherwise produced. Surprisingly, however, in the oxidative splitting of compound (3a), we do not obtain the aglycone but, directly, the compound (6R. 7R)-(-)-7-hydroxy-3-oxa-bicyclo[4.3.0]non-1-en - 9-one (4a), as water is simultaneously split off after the breaking up of the glucoside bond in the weak alkaline medium.
In the fifth reaction step, the compound (4a) is alkylated, acylated or condensed using methods more or less generally known in order to obtain, as required, the desired O-substituted derivatives of general formula I. The acylation of the 7-hydroxyl group of compound (4a) is performed with the corresponding carbonic acid anhydride or carbonic acid halogenide, for example with acetic anhydride, benzoyl chloride, p-nitrobenzoylchloride, methanesulfonyl chloride, toluenesulfochloride etc. Alkylation is performed in a corresponding manner using an alkyl halogenide with 1 to 5 carbon atoms, for example with ethyl bromide, with an aralkyl halogenide, for example benzyl chloride, with an alkyl sulphate or alkyl-p-toluene sulfonate. Condensation can be realized with every suitable compound, for example with tetrahydropyrane.
The compounds according to the invention can be used in a particularly advantageous manner as reactive intermediate products for the synthesis or the partial synthesis of natural substances, particularly of prostanoids.
It is known that the prostanoids or prostaglandins are counted as tissue hormones and exhibit a wide range of pharmacological efficacity. In particular, they have an effect on the smooth muscle tissue and on circulatory processes, are local modulators of hormonal effects, stimulate the secretion of prolactin, and take part in haemostasis as well as immunological resistance mechanisms. All mammal cells are capable of synthesizing prostaglandins. They are released by a large number of physiological, pharmacological and pathological stimuli.
H. Konig in: Klinische Wochenschrift
Vol. 53, pp. 1041-1048 (1975) provides a short summary on the chemistry and the metabolism of prostaglandins.
The compounds provided by the invention open up a new and chemically original method of synthesis leading to prostanoids, which are of extreme pharmacological importance; the initial steps of this process are obtained from the following formula scheme: ##STR7## In the first reaction step, benzylmercaptan or another suitable nucleophil, for example the N.tbd.C-group, is added to the double bond of the ketoenolether (4a). The addition of benzylmercaptan results in the formation of 1-benzylthio-7-hydroxy-3-oxa-bicyclo[4.3.0]nonan -9-one (5a). (Hereinafter, the symbol `SBz` means a compound having a benzyl group attached to the sulfur. The reaction step 4 for the production of the ketoenolether (4a) and the addition of benzylmercaptan can advantageously be performed in one procedure, directly following each other.
In the second reaction step, the compound (5a) is reduced with sodium borohydride to form (7R, 9S)-(-)-1-benzylthio-7,9-dihydroxy-3-oxa-bicyclo[4.3.0]nonane (6a) (Main Product) and to the (7R, 9R)-diasteromer (6b) (By-product). The diastereomers are quantitatively separated by column chromatography. The reaction may also be performed stereoselectively, so that only compound (6a) is formed (compare E. Martinez, J. M. Muchowski and E. Velade in: Journal of Organic Chemistry Vol. 42, p. 1087 (1977)).
The benzylthio groups of the compounds formed can be split off quantitatively using mercury acetate, whereby the corresponding 2,7,9-trihydroxy-3-oxa-bicyclo[4.3.0]nonanes (7a) and (7b) are produced.
The stereoisomeric series of compounds (5b), (6c), (6d) (7c) and (7d) are obtained by inverting the hydroxyl group on the C 7 -atom of compound (5a), this being in accordance with the procedure described by H. Loibner and E. Zbiral in Helv. Chim. Acta Vol. 59, p. 2100 (1976). The further reactions of compound (5b) to form compounds (7c) and (7d) are performed analogously to the reaction steps 2 and 3 described above.
The further reaction of compounds (7a) through (7d) to produce prostanoids is performed in accordance with the following formula scheme: ##STR8## In this case, the hemiacetals (7a) through (7d) are converted to form compound (8) with the by (7a) through (7d) pre-defined configuration using the relevant Wittig reagent, i.e. with correspondingly substituted monoalkyl-triphenyl-phosphonium salts (compare E. J. Corey et al. in: Journal of the American Chemical Society Vol. 93, p. 1490 (1971)). The primary hydroxyl group produced by the splitting of the pyran ring system in subsequently oxidized to aldehyde (9) with pyridinium dichromate (PDC) (comp. Tetrahedron Lett. 1979, 399) or with pyridinium chlorochromate (PCC) (comp. Tetrahedron Letters 1975, 2647). The second side chain of the prostanoid desired is, in its turn, also linked to compound (9) by means of a Wittig reaction (Wittig reagent: comp. J. S. Bindra and R. Bindra, Prostaglandin Synthesis, Academic Press, Inc., New York, 1977, p. 210). Finally, the protective groups R,R', R" and R'", for example acetyl-, benzyl-, benzoyl, p-nitrobenzoyl-, mesyl- and tosyl-groups as well as similar, known protective groups are split off in a fashion more or less generally known.
Particularly preferred embodiments of the invention result from following examples and the Patent Claims.
EXAMPLE 1
Catalpol (1a) from Picrorhiza kurrooa: Add 10 kg of the ground drug of Picrorhiza kurrooa to 100 kg of 5% soda solution and heat at 93°-95° C. for 3 hours by feeding in steam. Condensation of steam through the drug causes it to be whirled about, thus providing a good extraction. Filter through a perlon cloth overnight and extract the residue once more with 80 kg of 5% soda solution. Combine the filtrates and maintain at boiling heat for 20 minutes, then mix with 10 kg activated charcoal for 3 hours at 80° C. Leave the charcoal to settle overnight. Treat the decanted solution once more with 4 kg activated charcoal. Suck off the combined charcoal through an earthenware suction filter with a diameter of 60 cm with has previously been given a sediment layer of approx. 2 kg "Hyflo-Super-Cel"; then wash with water until the filtrate indicates a pH value of approx. 8. The air dried charcoal is boiled up three times, each time using 50 kg of 95% ethanol. After sucking off, approx. 166 kg solution is obtained which is initially concentrated in a distillery down to approx. 30 kg, and then reduced to dryness in a 100 liter rotary evaporator. Subsequent lyophilization results in a dark brown catalpol-concentrate containing still appreciable quantities of sugar and a little picroside mixture; yield: 1570 g (14.5% in relation to dried drug).
Add 300 g Al 2 O 3 (neutral, activity grade I) and 1.5 liter ethanol to 250 g of the catalpol concentrate. Mixing all the time, heat up to boiling and distill off 1.0 liter ethanol. This mixture is put onto an Al 2 O 3 column (100×5 cm; 1200 g Al 2 O 3 washed with ethanol) and eluated with a (9:1) mixture of ethanol and water. The fractions containing the catalpol are detected by thin-layer chromatographic evaluation (TLC: Rf=0.34; Solvent: CHCl 3 /CH 3 OH/2N CH 3 COOH 70:30:6) and combined. Evaporate the solution entirely in a vacuum at an immersion temperature of 52° C. to dryness. The foam initially produced is crystallized from ethanol. Suck off the crystals and wash well with ethanol. By means of column-chromatographic separation of the mother liquor via an Al 2 O 3 column it is possible to isolate a further quantity of catalpol.
Catalpol (1a), C 15 H 22 O 10 (362.3), yield 45 g (18% in relation to catalpol concentrate), melting point 202°-204° C., [α] 589 20 =-39.7° (c=1.2 g in 100 ml ethanol).
1st reaction step: Dissolve 15 g catalpol (1a) in 24 ml absolute pyridine at room temperature and add 30 ml acetic anhydride. Let the reaction solution stand for 15 hours at room temperature and subsequently pour into ice water. Knead the precipitated product until it assumes a solid form and can be filtered with suction. Wash the amorphous product with ice water, dry and recrystallize with a little ethanol.
Hexaacetyl-catalpol (1b), C 27 H 34 O 16 (614.6), yield 22 g (86%), melting point 142°-143° C., [α] 589 20 =-87.3° (c=1 g in 100 ml CHCl 3 ), Rf=0.34 (Solvent: benzene/acetone 8:2).
2nd reaction step: Dissolve 22 g hexaacetyl-catalpol (1b) in approximately 50 ml acetic ester and add 1.5 g Pd/C catalyst (10% Pd). Hydrogenate in the appropriate apparatus until no more hydrogen is absorbed (approx. 970 ml H 2 within approx. 2 hours; calc. 802 ml H 2 ). Filter off the catalyst and reduce the filtrate to dryness in vacuum (immersion temp. 45° C.) by evaporation.
Recrystallize the residue with a little ethanol.
Hexaacetyl-dihydrocatalpol (2b), C 27 H 36 O 16 (616.6), yield 22 g (99%), Melting Point 155°-156° C., [α] 589 20 =-80.4° (c=1 g in 100 ml CHCl 3 ), Rf=0.30 (benzene/acetone 8:2).
3rd reaction step: Add, in small portions, 18.4 g (30 mmole) hexaacetyl-dihydrocatalpol (2b) to a suspension of 7.4 g (195 mmole) LiAlH 4 in 1000 ml anhydrous tetrahydrofuran (THF), and boil for 4 hours under constant stirring and with reflux condensation. Decompose the surplus LiAlH 4 with acetic ester and water. After introduction of CO 2 , filter off the inorganic salts and wash the residue a number of times with water. Evaporate the THF in vacuum at an immersion temperature of 40° C. and heat the aqueous solution for three hours at 80° C. with 50 g activated charcoal (use stirrer). After decanting from the settled charcoal, treat the solution twice again, using 50 g activated charcoal each time. Thin-layer Chromatography is used to show that no more 3a is present in the aqueous solution. Suck off the charcoal and wash with water until no more inorganic salts can be detected. After air drying the carbon, extract it several times using 95% ethanol at boiling heat for 10 minutes. Reduce the collected filtrates to dryness in vacuum.
6,8-dihydroxy-8-(hydroxymethyl)-1-iridanyl-1'-β-D-glucopyranoside (3a), C 15 H 26 O 10 (366.4), yield 9.5 g (86%), amorphous [α] 589 20 =-77.1° (c=1.9 g in 100 ml CH 3 OH). Rf=0.27 (CHCl 3 /CH 3 OH/2N CH 3 COOH 60:50:6).
4th reaction step: Add 15 g (70 mmole) of sodium periodate to a solution of 5.5 g (15 mmole) 3a in 250 ml water. Allow the solution to stand at room temperature for half an hour, shaking from time to time. After adding 20 g sodium hydrogen carbonate (pH=8), filter off the inorganic salts and wash with 50 ml water. Reduce the filtrate by evaporation under vacuum at 35° C. immersion temperature until further inorganic salts start precipitating. Extract the colourless solution five times, using 100 ml acetic ester in each case. The acetic ester is dried with sodium sulphate and completely evaporated in vacuum at an immersion temperature of 35° C. The oil initially obtained crystallizes when subjected to rubbing. For analysis, dissolve the product in very little cold dioxane and add carbon tetrachloride to opacity. The substance 4a crystallizes out in the refrigerator.
(6R, 7R)-(-)-7-hydroxy-3-oxa-bicyclo[4.3.0]non-1-en -9-one (4a), C 8 H 10 O 3 (154.2), yield 1.8 g (78%), Melting Point 95°-97° C., [α] 589 20 =-267° (c=3 g in 100 ml CH 3 OH), Rf=0.32 (CHCl 3 /CH 3 OH 9:1)
Application of the Compounds according to the Invention for the Synthesis of Prostanoids
1st reaction step: Add, one after the other, 2 ml benzyl mercaptane and 0.2 ml triethylamine to a solution of 1.6 g (10.4 mmole) ketoenolether (4a) in 3 ml THF. Stir for 5 hours at room temperature. Evaporate the reaction solution of dryness in vacuum. Recrystallize the residue out of carbon tetrachloride.
1-(benzylthio)-7-hydroxy-3-oxa-bicyclo[4.3.0]nonan-one (5a), C 15 H 18 O 3 S (278.3), yield 2.3 g (79.6%), Melting Point 118° C., [α] 589 20 =-188° (c=2 g in 100 ml CHCl 3 ), Rf=0.23 (benzene/acetone 8:2).
2nd reaction step: At a temperature of -15° C. to -20° C., add dropwise a solution of 1.95 g (7 mmole) of the substance 5a in 20 ml absolute methanol to a solution of 265 mg (7 mmole) NaBH 4 in 20 ml absolute methanol within a period of approx. half an hour. Stir for four hours at a temperature of -15° C. Remove the cooling bath and allow the solution to warm up to room temperature by introducing carbon dioxide. During this process, add 50 ml water in drops. Shake out the reaction solution five times, using 50 ml ether each time. Dry the ether with anhydrous sodium sulphate and evaporate to dryness in vacuum. Then pass the residue through a pressure column measuring 80×2 cm filled with silica gel using, one after the other, 300 ml benzene, 1600 ml benzene/acetone (95:5) and 1600 ml benzene/acetone (90:10) and 1000 ml benzene/acetone (80:20). Determine the fractions by means of thin layer chromatography using a chloroform/methanol mixture (9:1) as solvent.
(7R, 9S)-(-)-1-(benzylthio)-7,9-dihydroxy-3-oxa-bicyclo-[4.3.0]nonane (6a), C 15 H 20 O 3 S (280.3), yield 1.13 g (57.6%), oil [α] 589 20 =-340° (c=1.6 g in 100 ml acetone), Rf=0.38 (CHCl 3 /CH 3 OH 9:1).
(7R, 9R)-(-)-1-(benzylthio)-7,9-dihydroxy-3-oxa-bicyclo[4.3.0]nonane (6b), C 15 H 20 O 3 S (280.3), yield 295 mg (15%), crystals from carbon tetrachloride, Melting Point 78°-79° C., [α] 589 20 =-154.9° (c=2 g in 100 ml acetone), Rf=0.32 (CHCl 3 /CH 3 OH 9:1).
3rd reaction step: Over a period of 3 minutes, add a solution of 280 mg (1 mmole) of the substance 6a or of the substance 6b in 3.5 ml acetonitrile dropwise to a solution of 175 mg (0.55 mmole) mercury acetate in 3.5 ml water. Stir for 10 minutes and dilute with 15 ml water. After filtration of the solution, reduce it to dryness by evaporating in vacuum. Purify the residue via a pressure column measuring 80×1 cm containing silica gel with a 9:1 mixture of chloroform/methanol.
(7R, 9S)-(-)-2,7,9-trihydroxy-3-oxa-bicyclo[4.3.0]nonane (7a), C 8 H 14 O 4 (174.2), yield 80%, oil, specific rotation not yet determined, Rf=0.24 (CHCl 3 /CH 3 OH 8:2).
(7R, 9R)-(-)-2,7,9-trihydroxy-3-oxa-bicyclo[4.3.0]nonane (7b) C 8 H 14 O 4 (174.2), crystals from a little acetone, yield 84%, Melting Point 108°-110° C., [α] 589 20 =-21.7° (c=1 g in 100 ml methanol), Rf=0.22, (CHCl 3 /CH 3 OH 8:2).
4th reaction step: Dissolve 1.3 g (4.7 mmole) of the substance 5a with 3.7 g (14 mmole) triphenylphosphine and 1.15 g (9.4 mmole) benzoic acid in 60 ml absolute benzene. With stirring, add in the form of drops a solution of 1.64 g (9.4 mmole) diethyl azodicarboxylate in benzene at room temperature (introducing the drops at a rate of one every three seconds). During the reaction, a white precipitate consisting of diethyl hydrazodicarboxylate is formed. As soon as the reaction solution assumes a weak yellow colour, terminate the reaction. By means of thin-layer chromatography no more initial substance can be detected. Remove the precipitate by suction and attach the precipitate to "Celite". Purify the substance via a pressure column measuring 80×2 cm with silica gel using a 95:5 mixture of benzene/acetone.
(6R,7S)-1-(benzylthio)-7-(benzoyloxy)-3-oxa-bicyclo[4.3.0]nonane -9-one (5b); R=benzoyl--) C 15 H 18 O 5 (278.3), yield 1.3 g (56%), oil, Rf=0.52 (benzene/acetone 8:2). The Rf value of 5b (R=benzoyl--) is different to that of 5a (R=benzoyl--) (Rf=0.64 in the same solvent). The product has not been examined further. By means of saponification, it should be possible to obtain 5b (R=H).
5th through 8th reaction steps: Further processing of the compounds 7a, 7b, 7c and 7d to prostanoids 11 is performed as described above (comp. p. 9 above). | Reactive iridoid derivates represented by the following general formula ##STR1## (wherein R represents a hydrogen atom, an alkyl group with 1 to 5 carbon atoms, an acyl group with 2 to 6 C atoms, an unsubstituted aralkyl group with 7 to 12 C atoms, a methanesulfonyl- or toluenesulfonyl group, a benzoyl-, a preferably para-substituted nitrobenzoyl- or chlorobenzoyl group, or a tetrahydropyranyl group), process for the manufacture of said derivatives starting from catapol as an easily obtainable natural substance and use of said derivatives as intermediates for the manufacture of prostanoids. | 2 |
BACKGROUND
1. Field of Invention
The teachings presented herein relate to electronic circuitry. More specifically, the teachings relate to methods and systems for digital data coding and electronic circuits incorporating the same.
2. Discussion of Related Art
A/D and D/A converters are widely used in the industry of electronics. In converting an analog signal to a digital signal, the analog signal is sampled at discrete points according to a certain frequency. Voltages of the analog signal at such sampled points are measured. Each measured voltage at a sampling point is then coded using a digital code having a plurality of binary bits. Such a digital code can be used to represent the sampled analog value and can be transmitted in a digital means to a destination. Once the digital code representing an analog value is received by a receiver, the digital code can be decoded by a D/A converter to derive an estimated voltage that is similar to the original voltage being coded. FIG. 1( a ) shows a typical A/D and D/A processing flow. In FIG. 1( a ), an A/D converter 110 takes an analog signal A as input and generates a digital code B as an output. The digital code B is often processed by a digital signal processor 115 to generate a digital signal C. When digital signal C is transmitted and received by a receiver 120 , which may then apply a D/A process at a D/A converter 130 and produces a recovered analog signal C′ based on digital signal C.
A digital code representing a particular sampled voltage of the analog signal is conventionally determined, by the A/D converter 110 based on a look-up table in accordance with the voltage level of the sample. For example, FIG. 1( b )(Prior Art) depicts a typical A/D converter 110 . An analog signal A is sampled first by an analog sampling unit 140 to produce individual analog voltages as an output. For each such analog voltage, an A/D look-up unit 150 determines a digital code representing the analog voltage based on a look-up table 160 .
A D/A converter reverses the process to convert a digital code to generate an analog voltage represented by the digital code. This is shown in FIG. 1( c ) (Prior Art), where a D/A look-up unit 170 in a D/A converter 130 consults with the look-up table 160 based on a received digital code C to produce an analog voltage. The represented analog voltage is then sent to an analog signal generator 180 , which may utilize different analog voltages to produce an estimated analog signal C′.
FIG. 1( d ) (Prior Art) shows an exemplary look-up table 160 in which the left column 190 lists various ranges of analog voltages and, correspondingly, the right column 195 provides 14-bit digital codes for different voltage ranges. For instance, for a zero voltage, the digital code is “00 0000 0000 0000”. For a voltage between +0.000122 v and +0.000244 v, the corresponding digital code is “00 0000 0000 0001”. For a voltage between −0.000122 v and −0.000244, the corresponding digital code is “11 1111 1111 1111”, etc.
In accordance with the conventional look-up table, as shown in FIG. 1( d ) (Prior Art), when an analog signal crosses 0V in a negative direction, all the binary bits of the digital code change state from 0 to 1. When a large number of digital outputs change at the same time in the same direction (from 1's to 0's or from 0's to 1s), noise current on the circuit board is induced because the output load capacitances are charged and discharged. In various applications such as communications, it is common to have an analog signal centered at 0 v and such an analog signal may also have frequent deviations from 0V. Consequently, all binary bits of a digital code will frequently change states which make the problem worse.
A previous solution for reducing digital noise is Gray Coding, as disclosed in U.S. Pat. No. 2,632,058 issued to F. Gray. This method solves the problem by allowing only one bit changing state between any two adjacent codes. Although such a solution solves the problem, a disadvantage of this approach is that its implementation requires complex circuitry for coding and decoding data. Therefore, a solution that both reduces digital noise and is cost effective is needed.
BRIEF DESCRIPTION OF THE DRAWINGS
The inventions claimed and/or described herein are further described in terms of exemplary embodiments. These exemplary embodiments are described in detail with reference to the drawings. These embodiments are non-limiting exemplary embodiments, in which like reference numerals represent similar structures throughout the several views of the drawings, and wherein:
FIG. 1( a )-( d ) (Prior Art) illustrate a conventional A/D and D/A flow and how analog information is digitally coded and decoded;
FIG. 2 depicts a high level block diagram for bit polarization format coding, according to an embodiment of the present teaching;
FIG. 3 shows a conversion table facilitating transformations from an analog voltage to a digital code and from a digital code to a modified digital code using bit polarization format, according to an embodiment of the present teaching;
FIG. 4 depicts a block diagram 400 incorporating BPF coding in the context of A/D and D/A flow, according to an embodiment of the present teaching; and
FIG. 5( a )-( e ) show different exemplary implementations of bit polarization coding according to embodiments of the present teaching.
DETAILED DESCRIPTION
The present teaching discloses methods and systems for realizing bit polarization format and application thereof. FIG. 2 depicts a high level block diagram 200 for bit polarization format coding, according to an embodiment of the present teaching. A digital code 205 is a binary code having a plurality of binary bits. For example, a digital code can have 14 binary bits, each of which has a state of either 0 or 1. Such a binary code may be an output from an A/D converter (not shown). According to the present teaching, when a digital code 205 is received, it is modified by a bit polarization format (BPF) unit 210 to produce a modified digital code 215 . Compared with the digital code 205 , the modified digital code 215 is derived by inverting a certain portion of the bit state of the digital code 205 . For example, substantially one half of the bits in the digital code 205 may be inverted. When the present teaching is deployed in connection with an A/D converter, employment of the bit polarization format is for the purpose of balancing the number of bits that change from 0s to is and the number of bits that change from 1s to 0s, especially when the analog signal is a small signal.
On the receiver side (not shown), when the modified digital code 215 is received, a BPF decoder 220 performs a reverse operation to recover the digital code 205 based on the modified digital code 215 . When the BPF coder 210 inverts a certain number of bits, the BPF decoder 220 applies inversion to the same bits that have been inverted by the BPF coder 210 . An exemplary BPF coding scheme is to alternate the bits to be inverted, namely alternate bit polarization format or ABPF. This ensures that one half of the bits are inverted when the total number of bits is an even number and a substantially one half of the total number of bits are inverted when the number of bits is an odd number. FIG. 3 illustrates an ABPF conversion table for the BPF coder 210 and BPF decoder 220 .
In FIG. 3 , a conversion table facilitates transformations from an analog voltage to a digital code and from a digital code to a modified digital code using bit polarization format, according to an embodiment of the present teaching. The left column 190 and the middle column 195 correspond to the left column 190 and right column 195 in FIG. 1( d ). The right column 310 in FIG. 3 corresponds to the BPF coding. For each digital code in the table (one row), the modified digital code can be derived by inverting every other bit in the given digital code. For instance, for a digital code with all zeros corresponding to analog voltage 0V, the modified digital code is “10 1010 1010 1010”. Similarly, for digital code “11 1111 1111 1111” corresponding to a small deviation from 0V, i.e., −0.000122V, the modified digital code is “01 0101 0101 0101”. As can be seen, from 0V to −0.000122V, the digital codes change from all zeros to all ones, which has the problem discussed herein. With the modified digital codes, about one half of such changes are avoided and, hence, to reduce the digital noise associated with the original digital code.
FIG. 4 depicts a block diagram 400 incorporating BPF coding in the context of A/D and D/A flow, according to an embodiment of the present teaching. The block diagram structure illustrated in FIG. 4 is largely similar to what is shown in FIG. 1 except for the incorporation of the BPF coder 210 and the BPF decoder 220 . In this depicted embodiment, a digital code generated by the A/D converter 110 is modified by the BPF coder 210 to generate a modified digital code according to a pre-determined coding scheme. Such a pre-determined scheme may correspond to what is illustrated in FIG. 3 or can be any coding scheme (some are shown in FIG. 5( a )-( e )) that is appropriate.
A receiver 410 in FIG. 4 decodes first, upon receiving the modified digital code, to recover the digital code that has been modified. Such produced digital code is then sent to the D/A converter to produce an estimate A′ for the original analog voltage A.
FIG. 5( a )-( e ) show different exemplary bit polarization formats according to embodiments of the present teaching. FIG. 5( a ) shows an exemplary scheme in which alternate bits are inverted to achieve bit polarization, according to an embodiment of the present teaching. In FIG. 5( a ), the left circuitry 510 represents an exemplary implementation of a BPF coder, having inverters arranged in alternate to achieve alternate bit inversion. The outputs of the circuit 510 collectively represent the modified digital code. The right circuitry 515 represents an exemplary implementation of a BPF decoder, having inverters arranged in the same configuration as in the BPF coder 510 to recover the original digital code. The outputs of the circuitry 515 collectively represent the decoded digital code.
FIG. 5( b ) shows a different exemplary scheme in which about one half of the bits are inverted to achieve bit polarization, according to an embodiment of the present teaching. In FIG. 5( b ), the left circuitry 520 represents an exemplary implementation of a BPF coder, having inverters arranged in the top end portion of the circuitry to invert the first one half of the bits. Such first one half may correspond to the least significant bits or most significant bits of a digital code. The right circuitry 525 represents an exemplary implementation of a BPF decoder, having inverters arranged in the same configuration as in the BPF coder 520 to recover the original digital code.
FIG. 5( c ) shows another different exemplary scheme in which about one half of the bits are inverted to achieve bit polarization, according to an embodiment of the present teaching. In FIG. 5( c ), the left circuitry 530 represents an exemplary implementation of a BPF coder, having inverters arranged in bottom end portion of the circuitry to invert the bottom one half of the bits. Such bottom one half may correspond to the most significant bits or least significant bits of a digital code. The right circuitry 535 represents an exemplary implementation of a BPF decoder, having inverters arranged in the same configuration as in the BPF coder 530 to recover the original digital code.
FIG. 5( d ) shows yet another different exemplary scheme in which about one half of the bits are inverted to achieve bit polarization, according to an embodiment of the present teaching. In FIG. 5( d ), the left circuitry 540 represents an exemplary implementation of a BPF coder, having inverters corresponding to about one half of the total number of bits of a digital code and arranged in a consecutive manner in any middle portion of the of the circuitry to invert corresponding one half of the bits. By middle portion, it can be anywhere as long as it does not include the least and most significant bits. The right circuitry 545 represents an exemplary implementation of a BPF decoder, having inverters arranged in the same configuration as in the BPF coder 540 to recover the original digital code.
FIG. 5( e ) shows another different exemplary scheme in which about one half of the bits are inverted to achieve bit polarization, according to an embodiment of the present teaching. In FIG. 5( e ), the left circuitry 550 represents an exemplary implementation of a BPF coder, having inverters corresponding to about one half of the total number of bits of a digital code and arranged in a plurality of clusters, each may have a different number of inverters and scattered in non-adjacent portions of the circuitry to invert corresponding one half of the bits. The right circuitry 555 represents an exemplary implementation of a BPF decoder, having inverters arranged in the same configuration as in the BPF coder 550 to recover the original digital code.
All embodiments disclosed have simple and cost effective implementations, yet can achieve the goal of avoiding having all bits changing states at the same time and, hence, reduce the digital noise.
While the inventions have been described with reference to the certain illustrated embodiments, the words that have been used herein are words of description, rather than words of limitation. Changes may be made, within the purview of the appended claims, without departing from the scope and spirit of the invention in its aspects. Although the inventions have been described herein with reference to particular structures, acts, and materials, the invention is not to be limited to the particulars disclosed, but rather can be embodied in a wide variety of forms, some of which may be quite different from those of the disclosed embodiments, and extends to all equivalent structures, acts, and, materials, such as are within the scope of the appended claims. | A method and system for converting a digital code. A digital signal is encoded to have a digital code having multiple binary bits. Substantially one half of the binary bits of the digital code is inverted to produce a modified digital code to reduce digital noise associated with the digital code. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates generally to ergonomic peripheral device support assemblies, and more specifically to an ergonomic keyboard and mouse pad supporting tray and arm rest for use with conventional open arm office chairs.
The typical computer mouse rests on a desk adjacent a computer monitor. The keyboard may also lie next to the monitor or alternatively may be housed in front of the keyboard. Often this arrangement causes a user to hold his wrist in an angled position that has been shown to cause carpal tunnel and other health ailments in users who sit at their computer for hours at a time.
To alleviate this problem, many users place the keyboard in a pull out tray that is positioned near their lap. However, the mouse is often still at another location. As such, the user must still position his wrist at an awkward angle when using the mouse. In addition, the mouse is not convenient to the keyboard in this position.
Thus there remains a need in the art for an improved keyboard support tray and arm rests for conventional open arm office chairs. There also remains a need for a detachable armrest and support tray that provides hinged armrests that can fold and swivel to positions out of the way of the user, can be retrofitted onto existing chairs, is easy to install, and provides arm rest and work surfaces for the use of both a keyboard or laptop computer, mouse, or other peripheral devices.
SUMMARY OF THE INVENTION
The present invention addresses one or more of those needs in the art by providing a detachable armrest and support tray for supporting a peripheral device including a first portion having a mount adapted to be mounted onto an armrest in a defined configuration for securing the first portion to the armrest; and a second portion pivotally attached to the first portion such that the second portion may pivot from a first position over the first portion for storage to a second position in which the first and second portions are generally aligned with the armrest when the mount is mounted in the defined configuration.
The mount may be selected from the group consisting of clamps, hook and loop fasteners, and combinations thereof. The second portion preferably has a surface that is sized and configured to accommodate a mouse pad. The first portion may be attached to the mount by a tether. The detachable armrest and support tray may be made of a material selected from the group consisting of plastics, wood, metals, and combinations thereof.
Typically, there are two detachable armrests.
A preferred embodiment includes a tray sized to span a distance between two detachable armrest and support trays mounted in the defined configuration on armrests of a chair for providing additional work area. Preferably, the tray is sized and configured to hold a computer keyboard. It can also be sized and configured to hold a laptop computer. Preferably, the tray has a textured surface to inhibit sliding of items placed on the tray. If the tray has a proximal end and a distal end, the tray may slope downward from the distal end to the proximal end.
The first portion may have padding positioned to provide comfort to a user. The second portion may be attached to the first portion by a hinge.
These and other aspects of the present invention will become apparent to those skilled in the art after a reading of the following description of the preferred embodiment when considered with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an embodiment of a peripheral device support assembly of the present invention;
FIG. 2 is a perspective view of an embodiment of the tray constructed according to the present invention;
FIG. 3 is a perspective view of a left oriented detachable armrest and support trays of FIG. 1 ;
FIG. 4 is a perspective view of a right oriented detachable armrest and support tray of FIG. 1 ;
FIG. 5 is a bottom perspective view of the detachable armrest and support tray of FIG. 1 ;
FIG. 6 is a bottom perspective view of the detachable armrest and support tray of FIG. 1 in a storage position;
FIG. 7 is a perspective view of a second embodiment of a detachable armrest and support tray; and
FIG. 8 is a perspective view of a third embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows an embodiment of a peripheral device support assembly 10 . The peripheral device support assembly 10 is preferably made of ABS plastic. However, other materials including other plastics, metal, wood, and combinations thereof may be used.
The peripheral device support assembly 10 includes two detachable armrest and support trays 11 . The detachable armrest and support tray 11 includes a first portion 12 and a second portion 14 that is pivotally connected to the first portion 12 by a hinge 26 . As seen in FIG. 1 , the second portion has a butt-like protrusion 30 . The protrusion 30 abuts a forward edge 32 of the first portion when the second portion is extended for use. This abutment limits the travel of the second portion so that the second portion stops generally parallel and coplanar with the first portion. As seen in FIG. 6 , the second portion 14 may fold over the first portion 12 for storage.
In other embodiments, the second portion 14 may be connected to the first portion 12 by other connectors such as clamps, glue, welding, and any other connector. Alternatively, the first portion 12 and the second portion 14 may be molded as one piece.
As seen in FIG. 1 , the first portion 12 is covered with foam rubber padding 13 for the comfort of a user. Other types of padding may also be used. The second portion 14 may include a surface 16 that is sized and configured to accommodate a computer mouse or other peripheral device. The surface 16 may be covered with a material to form a computer mouse pad on the surface 16 . Alternatively, the surface 16 may also be used for writing and other such activities.
In an embodiment, two detachable armrest and support trays 11 may be used. A tray 18 may span between each detachable armrest and support tray 11 . The tray 18 has a work surface 25 that is sized and configured to accommodate a laptop computer, keyboard, or other peripheral device. The tray 18 may also provide writing or other workspace. The tray 18 is also sized and configured to span the distance between two detachable armrest and support trays 11 . The tray 18 may rest on the second portion 14 of each detachable armrest and support tray 11 or the tray 18 may be mounted to the second portion 14 using clamps, tape, hoop and loop fasteners, or any other suitable mount. As shown, a ridge on top of the portion 14 at the inside edge extends into a groove on the bottom of the edge of tray 18 , inhibiting left-to-right shifting of the position of tray 18 .
As seen in FIG. 2 , the tray 18 has a proximal end 20 and a distal end 22 . Preferably, the edge of the tray is sloped downward from the distal end 22 to the proximal end 20 . Alternatively, the tray may be flat or may be sloped downward from the proximal end 22 to the distal end 20 . Also, a textured lining 24 may be applied to the work surface 25 to prevent materials from sliding down the slope from the second end 22 to the first end 20 . Preferably, the tray's work surface 25 is formed with a textured surface. Alternatively the tray 18 may have a smooth surface.
FIG. 3 is a perspective view of a left-hand oriented detachable armrest and support tray 11 . FIG. 4 is a perspective view of a right-hand oriented detachable armrest and support tray. The second portion 14 of each detachable armrest and support tray 11 is shaped such that the second portion 14 is straight on the interior, so that a user's path to the seat is unencumbered by the second portion 14 . In other embodiments, the detachable armrest and support tray may not have a specific orientation.
The second portion 14 is sized and configured to provide space for a mouse or other peripheral device. However, it is not necessary to make the second portion a specific shape. Any shape such as a circle, rectangle, square, triangle, or other shape is sufficient so long as it provides work space for the user. A mouse pad may be mounted permanently or temporarily to the surface of the second portion 14 .
FIG. 5 is a bottom perspective view of the first embodiment of the detachable armrest and support tray 11 . The detachable armrest and support tray 11 includes a first portion 12 and a second portion 14 . The first portion 12 may be attached to an existing armrest using a mount 28 such as clamps, hook and loop fasteners, and any other mount. As seen in FIG. 5 , the first portion 12 is held in place by a mount 28 . Preferably, the mount 28 includes two mounting bars 15 . The bars 15 are sized and configured to fit underneath the first portion 12 between the two downward-extending sides of the portion 12 . Screws are inserted through the top 11 into threaded inserts in the mounting bars 15 . This allows adjustment for different thickness in armrests.
To install a detachable armrest and support tray 11 , a user places the first portion 12 over an armrest 77 , positions the bars 15 underneath the armrest, aligns the screw holes in the ends of the bar with the screw holes in the side of the first portion 12 , and inserts screws through the holes in the first portion 12 and into the screw holes in the ends of the bar.
FIG. 6 is a bottom perspective view of the first embodiment of a detachable armrest and support tray 11 in a folded position. In an embodiment, the detachable armrest and support tray 11 includes a first portion 12 and a second portion 14 that is hingedly connected to the first portion 12 so that the second portion 14 may fold over the first portion 12 for storage. The second portion 14 is connected to the first portion 12 by a hinge 26 . Other connectors or configurations that enable the second portion 14 to fold over the first portion 12 may be used in lieu of a hinge 26 .
FIG. 7 is a perspective view of a second embodiment of a detachable armrest and support tray 55 including a molded portion 60 that is attached to the mount 28 in such a way as to allow the molded portion 60 to swivel in relation to the affixed portion 29 so that the detachable armrest and support tray 11 may be stored to the side of a chair while the portion 29 remains attached to an existing armrest. The tray 55 may be attached to the mount 28 by a tether 50 . The tether 50 may be a hinge pin, bungee cord, or any other flexible material that allows for two attached items to move in relation to one another. The molded portion 55 may swivel latitudinally and longitudinally in relation to the mount 28 so that the molded portion 60 rests to the side of the mount 28 .
In the view of FIG. 7 , the tether 50 is an L-shaped pivot, allowing pivoting about each leg of the L. One leg is in the rear of the portion 29 and the other is in the outside edge of the portion 60 . To mount the portion 60 on the portion 29 so as to make a useable surface, one rotates the portion 60 from the view of FIG. 7 forwardly, causing rotation about the leg of the L in the rear of the portion 29 . This continues until the portion 60 is rotated through about 180° from the position shown in FIG. 7 . Then, the portion 60 is rotated about the leg of the L in the portion 60 , toward the seating surface of the chair, until the lower side flanges of portion 60 are above the spaces on either side of portion 29 . Then the portion 60 is rotated about the leg of the L in the portion 29 downwardly onto the portion 29 , with the sides of portion 60 straddling the portion 29 .
FIG. 8 is a perspective view of a third embodiment of a detachable armrest and support tray 111 . The detachable armrest and support tray 111 includes a first portion 112 and a second portion 114 that is pivotally attached to the first portion 112 by a hinge 126 so that the second portion 114 may fold over the second portion 112 for storage. The first portion 112 is attached to the mount 128 by a tether 150 so that the mount 128 may swivel in relation to the mount 128 for storage.
To store the detachable armrest and support tray 111 a user may fold the second portion 114 over the first portion 112 . Then the user may lift the first portion upward, turn the first portion counterclockwise one quarter turn, and then turn the first portion clockwise a half turn.
Certain modifications and improvements will occur to those skilled in the art upon a reading of the foregoing description. It should be understood that all such modifications and improvements have been deleted herein for the sake of conciseness and readability but are properly within the scope of the following claims. | A peripheral device support assembly. The peripheral device support assembly includes two detachable armrest and support tray adapted to be attached to each arm of an office chair. The detachable armrest and support tray includes a mount for securing the armrest support unit to a chair arm and a first portion hingedly attached to the mount for allowing the first portion to swivel in relation to the mount. The detachable armrest and support tray also includes a second portion pivotally connected to the second portion such that the first portion folds back over a second portion for storage. A tray spans the distance between the second portion of each detachable armrest and support tray to provide additional workspace. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to detecting devices for detecting malfunctions or marked abrasion of a bearing for a shaft.
2. Description of the Prior Art
One of the above-mentioned detecting devices is shown in Japanese Utility Model Second Provisional Publication 52-35379. In the device of the publication, a so-called "shaft vibration detecting piece" is radially movably arranged near a shaft which is rotatably held by a bearing. When, due to marked abrasion of the bearing, the shaft is subjected to abnormal vibration in radial direction, the shaft vibration detecting piece is shifted outward by the shaft to a position to actuate a limit switch. Thus, the marked abrasion of the bearing, which causes the abnormal rotation of the shaft, can be detected by the operation of the limit switch.
However, due to its inherent construction, the above-mentioned conventional detecting device has the following drawback.
That is, the conventional device can not detect an abnormal abrasion of the bearing which causes axial vibration of the shaft. In fact, even when the axial vibration of the shaft occurs due to peeling of parts of the bearing or the like, the shaft vibration detecting piece is not moved by the shaft. In this case, there is a possibility that the severely worn bearing is used until the same is completely broken. Of course, this is a serious matter because pieces in the broken bearing tend to induce trouble of a system in which the bearing is employed.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a device for detecting malfunctions of a bearing for a shaft, which is free of the above-mentioned drawback.
According to a first aspect of the present invention, there is provided a bearing malfunction detecting device for use in an arrangement which includes a fixed support member, a bearing held by the support member and a shaft rotatably held by the bearing. The bearing malfunction detecting device comprises a first member connected to the shaft to rotate therewith; a second member connected to the fixed support member at a position near the first member, the second member having a recessed head portion which spacedly receives therein a peripheral portion of the first member; and detecting means for detecting a breakage of the recessed head portion.
According to a second aspect of the present invention, there is provided a bearing malfunction detecting device for use in a water pump which is associated with an internal combustion engine and comprises a pump body secured to a cylinder block of the engine, a bearing installed in the pump body, a shaft rotatably held by the bearing and driven by the engine and a pump impeller coaxially connected to the shaft. The bearing malfunction detecting device comprises an annular plate coaxially and securely disposed about the shaft to rotate therewith; a wire carrier connected to the pump body at a position near the annular plate, the wire carrier having a recessed head portion which spacedly receives therein an peripheral portion of the annular plate; and detecting means for detecting a breakage of the recessed head portion.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the present invention will become apparent from the following description when taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a sectional view of a water pump to which a bearing malfunction detecting device of the present invention is practically applied;
FIG. 2 is an enlarged sectional view of an essential portion of the bearing malfunction detecting device of the invention;
FIG. 3 is a view similar to FIG. 2, but showing a condition wherein a part of a detector unit is broken; and
FIG. 4 is a graph showing the degree of axial vibration of a shaft with respect to the time elapsed.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings, particularly, FIG. 1, there is shown a water pump 1 to which a bearing malfunction detecting device according to the present invention is practically applied.
Prior to making a detailed description of the bearing malfunction detecting device of the invention, the water pump 1 will be outlined.
The water pump 1 is associated with an automotive internal combustion engine to pump up cooling water for the engine.
In FIG. 1, denoted by numeral 3 is a pump body. The pump body 3 has at its right portion a flange (no numeral) secured to a cylinder block (not shown) of the engine through bolts (not shown). The cylinder block has therein a pump chamber in which an after-mentioned pump impeller 6 is installed. A shaft 4 is rotatably received in the pump body 3 through a bearing 2. The shaft 4 has at its left end a sprocket wheel 5 secured thereto. The sprocket wheel 5 is meshed with a chain (not shown) which is put around a crankshaft of the engine and a cam shaft of the same. Thus, when the engine operates, the shaft 4 is driven or rotated by the chain. The shaft 4 has at its right portion the pump impeller 6 secured thereto. A known mechanical seal 7 is arranged at a left side of the pump impeller 6 keeping a certain annular space between the seal 7 and the bearing 2. The pump body 3 is formed with a steam passage 3A through which steam in the space is discharged. In fact, under operation of the engine, part of steam in the pump chamber is forced to penetrate into the space through the mechanical seal 7. Although not shown in the drawings, the pump body 3 has further a water drain passage from which water in the space is drained.
Under operation of the engine, the shaft 4 is rotated and thus the pump impeller 6 is rotated in a given direction. Due to rotation of the pump impeller 6, cooling water is forced to flow from an inlet port (not shown) of the pump chamber toward an outlet port (not shown) of the same.
In the following, the bearing malfunction detecting device of the present invention will be described in detail.
As is seen from FIG. 1, the detecting device comprises an annular plate 11 which is coaxially and securely disposed through its flange portion on the shaft 4 in the annular space. Thus, the annular plate 11 rotates together with the shaft 4, and thus the annular plate 11 can serve as a slinger ring by which water in the annular space is slung radially outward.
Near a peripheral portion 11A of the annular plate 11, there is located a wire carrier 12 which is secured to the pump body 3. The wire carrier 12 has a generally U-shaped head portion which comprises spaced side walls 12A and 12B and a bottom wall 12C. The side walls 12A and 12B are spaced from each other in the direction parallel with the axis of the shaft 4. The peripheral portion 11A of the annular plate 11 is spacedly received in the U-shaped head portion of the wire carrier 12. That is, each of the three walls 12A, 12B and 12C is spaced from the peripheral portion 11A of the annular plate 11 by a given distance.
As is seen in FIG. 2, the U-shaped head portion of the wire carrier 12 has thereon a wire 13 which extends in series along the side wall 12A, the bottom wall 12C and the other side wall 12B. That is, the wire 13 has at least three portions which extend sufficiently in the areas of the three walls 12A, 12B and 12C respectively. The wire 13 has opposed ends to which respective terminals 14A and 14B are connected. Thus, the wire 13 constitutes a series circuit between the two terminals 14A and 14B.
Each wall 12A, 12B or 12C of the U-shaped head portion of the wire carrier 12 is so constructed as to be broken when the peripheral portion 11A of the annular plate 11 abuts the wall 12A, 12B or 12C during rotation of the annular plate 11. Of course, when the wall 12A, 12B or 12C is broken, the corresponding portion of the wire 13 is broken. The wire carrier 12 is entirely or partially constructed of a somewhat breakable material, such as a semi-rigid sintered material or the like. Of course, by reducing the thickness of the wire carrier 12, the rigidity of the same can be reduced.
Referring back to FIG. 1, to the terminals 14A and 14B of the wire 13, there is connected, through wires (no numerals), a warning circuit 15 by which the breakage of the wire 13 at the U-shaped head portion of the wire carrier 12 is visually or acoustically indicated. The warning circuit 15 is equipped with a relay or the like which is actuated when the series circuit of the wire 13 between the terminals 14A and 14B is broken.
In the following, operation of the bearing malfunction detecting device of the invention will be described with reference to the drawings.
For ease of understanding, the description will be commenced with respect to a normal condition of the bearing 2 of the water pump 1, which is shown in FIGS. 1 and 2. Under this condition, there is no vibration of the shaft 4. Thus, the annular plate 11 secured to the shaft 4 rotates freely without contacting the U-shaped head portion of the wire carrier 12. Of course, under this condition, the warning circuit 15 does not issue any warning.
When, due to marked abrasion of the bearing 2 or the like, the shaft 4 is subjected to axial vibration, the peripheral portion 11A of the annular plate 11 abuts against at least one of the side walls 12A and 12B of the wire carrier 12 and breaks the same, as is seen from FIG. 3. With this, the series circuit of the wire 13 is broken, and thus the warning circuit 15 issues a visual or acoustic alarm letting the operator realize marked abrasion of the bearing 2.
FIG. 4 is a graph which shows the degree of the axial vibration of the shaft 4 with respect to the time elapsed. As is seen from this graph, due to advancing abrasion of the bearing 2, the degree of the axial vibration increases with increase of the time. In the graph, denoted by reference "T 1 " is the time when the bearing 2 exhibits an initial severe abrasion and denoted by reference "T 3 " is the time when the bearing 2 is completely broken. Denoted by reference "T 2 " is the time when one of the side walls 12A and 12B of the U-shaped head portion of the wire carrier 12 should be broken due to the marked abrasion of the bearing 2.
When, due to marked abrasion of the bearing 2 or the like, the shaft 4 is subjected to radial vibration, the peripheral portion 11A of the annular plate 11 abuts against the bottom wall 12C of the wire carrier 12 and breaks the same. With this, the warning circuit 15 issues a visual or acoustic alarm, like in the case of the above-mentioned axial vibration of the shaft 4.
As is seen from the above, in accordance with the present invention, the marked abrasion of the bearing 2 (viz., abnormally worn condition of the bearing 2) can be detected by not only the radial vibration of the shaft 4 but also the axial vibration of the shaft 4. Thus, the bearing malfunction detecting device of the invention has a higher detectability as compared with the above-mentioned conventional device.
The following modification is available in the present invention.
That is, when a system including the wire 13 and the warning circuit 15 is connected to each of the three walls 12A, 12B and 12C of the wire carrier 12, the characteristic of the shaft vibration is known and thus the abrasion of the bearing 2 can be much more highly analyzed. | A bearing malfunction detecting device can detect abnormal abrasion of a bearing by which a shaft is rotatably held. The detecting device comprises an annular plate coaxially and securely disposed about the shaft to rotate therewith. A wire carrier is connected to a fixed support member at a position near the annular plate. The wire carrier has a recessed head portion which spacedly receives therein an peripheral portion of the annular plate. A detecting device is used for detecting breakage of the recessed head portion. | 6 |
CLAIM TO PRIORITY OF PROVISIONAL APPLICATION
[0001] This application claims priority under 35 U.S.C. §119(e)(1) of provisional application Nos. 60/680,624, filed May 13, 2005 and 60/681,427, filed May 16, 2005.
TECHNICAL FIELD OF THE INVENTION
[0002] The technical field of this invention is processor and memory emulation technology.
BACKGROUND OF THE INVENTION
[0003] During applications code development, the development team traverses a repetitive development cycle shown below hundreds if not thousands of times:
1. Building code—compile and link a version of applications code 2. Loading code—loading the code into real hardware system or a software model 3. Debugging/Profiling code—chasing correctness or performance problems 4. Making changes—making source code edits, or changing the linker directives
[0008] The load and change portions of this cycle are generally viewed as non-productive time, as one is either waiting for code to download from the host to the target system or looking through files that need changes and making changes with a text editor.
[0009] Any trip through the loop can either introduce or eliminate bugs. When bugs are introduced, the development context changes to debug. When sufficient bugs are eliminated, the development context may change to profiling. There are obviously different classes of debug and profiling, some more advanced than others. Profiling can involve code performance, code size and power. The developer bounces between the concentric rings of the development context, as the applications code development proceeds.
[0010] Special emphasis must be placed on getting to the developer the system control, data transfers, or instrumentation applicable to the current debug or profiling context. This requires packaging the system control and instrumentation in readily accessible systems solutions form, where developers can easily access tools with capabilities targeting specific development problems. The presentation of capabilities must expose the complete capability of the toolset while making the selection of right capability for the task at hand straightforward.
[0011] The need for emulation has significantly increased with the introduction of cache based architectures. This increased need primarily arises from the fact that on flat memory model architectures such as the Texas Instruments C620× devices, the performance that can be expected from running on the target could be accurately modeled with a simulator. The actual system performance with interrupts and Direct Memory Access (DMA) was within 10-15% of the simulated performance. This margin was reasonable for most applications of interest.
[0012] With the introduction of cache based architectures and the inability to model cache events and their impact on system performance accurately, today's developers find simulated performance to be anywhere from 50-100% away from the actual target performance. This inaccuracy results in a loss of confidence about the capabilities of the device and leads to fictitious performance de-rating factors between cache and flat memory performance. While some of the discrepancy between simulated and actual performance is due to inadequate modeling of the cache, there still exists a fundamental problem in modeling system related interactions such as interrupts or DMA accurately. Hence simulators typically have tended to play catch up with the target in modeling the system accurately. The period over which the simulator for a given target matures is unfortunately the same time that a developer is attempting to get to market.
[0013] Visibility into what the target is doing is key to extracting performance on cache-based architectures. The way to get this visibility for profiling system performance is through emulation. Visibility is also key for those writing behavioral simulators to countercheck the behavior of the target against what is expected. It is key to software developers in helping to reduce cache related stalls that impact performance. Visibility on the target is invaluable for system debug and development of applications in a timely manner. The absence of visibility leaves software developers with little else but to speculate about the probable reasons for loss of performance. The inability to know what is going on in the system leads to a trial and error approach to performance improvement that is gained by optimal code and data placement in memory. The lack of proper tools that allow for cache visualization precludes one from answering the question “Is this the most optimal software implementation for this target?” The ability to know if a given software module ever missed real-time in an actual system is of utmost importance to system developers who are bringing up complex systems. Such questions can be only accurately answered by the constant and non-intrusive monitoring of the actual system that advanced emulation offers.
[0014] Visibility is key in aiding complex system debug. Debugging memory corruption and being able to halt the CPU when such a corruption is detected is of primary importance, as memory exceptions are not currently supported on Texas Instruments C6× targets. In addition on the C6× Digital Signal Processor (DSP) data memory corruption can also result in program memory corruption causing the CPU execution to crash, as program and data share a unified memory. There is therefore a need to accurately trace the source code that is causing this malicious behavior. The ability to monitor Direct Memory Access (DMA) events, their submissions and completions relative to the CPU will provide additional dimensions to the programmer to tune the size of the data sets the algorithm is working on for more optimal performance. The ability to catch and warn users about spurious CPU writes or DMA writes to memory can prove to be invaluable in cutting down the software debug time. Advanced emulation features once again hold the key to all these critical capabilities. The need for good visibility only gets more serious with the introduction of multiple CPU cores moving forward. The need to know which CPU currently has access to a shared common data resource will be a question of prime importance in such scenarios. The detection and warning of possible memory incoherence is another critical capability that emulation can offer.
[0015] The new emulation features will provide enhanced debug and profiling capabilities that allow users to have better visibility into system and memory behavior. Further, several usability issues are addressed.
[0016] The aim is to make new debug and profiling capabilities available and fix problems encountered in previous implementations:
Stall cycle profiling to identify parts of the user application that requires code optimization. Event profiling to analyze system and memory behavior which in turns allows to choose effective optimization methods. Cache viewer and coherence analysis to debug cache coherence problems. Software Pipelined Loop instruction (SPLOOP) Debug. Support for Memory protection and security Reduce Real-time Data Exchange intrusiveness. Richer set of Advanced Event Triggering events.
SUMMARY OF THE INVENTION
[0024] When multiple debug tools are connected to a target system it is desirable to coordinate the functions of the multiple debug systems. This coordination may need to be close to the physical connection. The coordination may involve defining the width of the trace word, coordination of execution control, or the issuance of global triggers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] These and other aspects of this invention are illustrated in the drawings, in which:
[0026] FIG. 1 shows compression of trace words;
[0027] FIG. 2 shows compression of trace packets;
[0028] FIG. 3 demonstrates data extraction;
[0029] FIG. 4 shows clock source selection;
[0030] FIG. 5 shows input delay lines;
[0031] FIG. 6 illustrates dual channel operation for skew adjustments;
[0032] FIG. 7 shows the digital delay lines;
[0033] FIG. 8 shows the delay line control signals;
[0034] FIG. 9 demonstrates delay line cross coupling;
[0035] FIG. 10 illustrates tap measurement with a split delay line;
[0036] FIG. 11 shows a multi input recording interface;
[0037] FIG. 12 shows an alternate implementation of a multi input recording interface;
[0038] FIG. 13 shows chip and trace unit interconnections;
[0039] FIG. 14 shows clock insertion delay cancellation;
[0040] FIG. 15 is a block diagram showing scaled time simulation;
[0041] FIG. 16 is a distributed width trace receiver;
[0042] FIG. 17 is a flow diagram of a distributed depth trace receiver;
[0043] FIG. 18 shows message insertion into the trace stream;
[0044] FIG. 19 is a block diagram of a last stall standing implementation; and
[0045] FIG. 20 shows an example of a self simulation architecture.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0046] Trace data is stored in trace memory as it is recorded. At times, the trace data may be repetitive for extended periods of time. Certain sequences may also be repetitive. This presents an opportunity to represent the trace data in a compressed format. This condition can arise when certain types of trace data are generated e.g., trace timing data is generated when program counter (PC) and data trace is turned off and timing remains on.
[0047] The trace recording format accommodates compression of consecutive trace words. When at least two consecutive trace words are the same value, the words 2 through n are replaced with a command and count that communicates how many times the word was repeated. The maximum storage for a burst of 2 through n words is two words as shown in FIG. 1 , where word 101 does not repeat, words 102 , 103 , 104 and 105 are identical and then words 106 and 107 are identical. This sequence compresses as follows—word 108 is the same as word 101 , word 109 has the value of word 102 , and word 110 contains a 3 as the repetition factor for word 109 . Similarly, words 106 and 107 are identical, and are encoded as word 111 containing the value of word 106 while word 112 contains the repetition factor of 1.
[0048] This concept may be extended to data of any width before it is packed into words. In this case packets or packet patterns (sequences) may be recorded in compressed form. It is not necessary for the packets or patterns to be word aligned. This is shown in FIG. 2 , where packet 201 does not repeat, packets 202 , 203 , 204 and 205 are identical and then packets 206 and 207 are identical. This sequence compresses as follows—packet 208 is the same as packet 201 , packet 209 has the value of packet 202 , and packet 210 contains a 3 as the repetition factor for packet 209 . Similarly, packets 206 and 207 are identical, and are encoded as packet 211 containing the value of packet 206 while packet 212 contains the repetition factor of 1. Data recording of single ended signals may use two out of phase clocks to extract the data to substantially lessen the effects of duty cycle distortion. Using of two out of phase clocks makes the data extraction logic considerably more tolerant of the input duty cycle distortion induced by any component (on-chip or off chip) before the data is extracted from the transmission at the receiver.
[0049] The use of two clocks, hereafter called BE_BP mode (both edges, both phases), deals with the duty cycle distortion created by circuitry between the transmitter and receiver. If certain factors distort the waveform, the duty cycle could be as poor as 80%/20% by the time the data reaches the capture circuit.
[0050] Data from both a positive edge sample and negative edge sample are used to derive the data bit value stored in a circular buffer in BE_BP mode. The primary and secondary clocks capture two copies of the data. A sample is taken with the positive edge of one clock and the negative edge of the other clock during each bit period. These two captured data values are combined to create the data bit value (along with the data value captured by the previous negative edge). The captured data is clocked into the circular buffer based on the clock edges sampling the data.
[0051] BE_BP delivers better bandwidth by utilizing the fact that signals switching in the same direction will have similar distortion characteristics. This is best understood by following an example. Beginning with a data bit that is a zero for multiple bit periods, the data moves to a one. Assuming there is distortion in the duty cycle, the rising edge of the data input has similar characteristics to the rising edge of the clock moving high at the bit period where the data bit moves to a one. Since the bit is a zero previously, the data sampled by the clock that is rising used to define the next data bit. Once the data bit is a high, the falling edge of the clock moving low at the bit period where the data bit moves to a zero is used to determine the bit value. The data extraction algorithm is defined by the following equation:
if (last bit ==0) {data=data sampled by next rising edge clock;}
[0052] else {data =data sampled by next falling edge clock;}
[0053] When a bit is sampled as a one by the positive and negative edges of the clock, the data is assumed to be a one. If the data sampled by the positive edge indicates a one while data sampled by the negative edge indicates a zero, the bit timing is close or the waveform is distorted. In this case the data sampled by the previous bit's negative edge is checked. If this data was captured as a zero, the data for this bit is declared a one because the data bit must be transitioning from a zero to a one. The converse is also true.
[0054] Looking at FIG. 3 , one can see how data extraction works. As the equation above shows, data extraction is based on the last data bit extracted at 306 (DATA), data in 303 (DIN), and two clocks that are out of phase with each other 301 and 302 (CLK 1 and CLK 0 ). The data sampled by each edge of CLK 1 is shown at 304 (SMP 1 ) while the data sampled by each edge of CLK 0 is shown as 305 (SMP 0 ). Looking at points 307 (A) and 308 (B), the SMP 0 value is used for data as the prior data value is a zero moving to a one at A while the SMP 0 value is used for data as the prior value is a one moving to a zero at B. Note that the duty cycle distortion causes erroneous data values sampled by CLK 1 (SMP 1 ) at points A and B.
[0055] A single trace receiver may be used to record trace data from multiple trace transmitters. It may also be used to accept trace data from a cascaded trace unit, receiving data from another unit. In the example shown in FIG. 4 , each input 401 may be used as either clock 403 or data 405 , as selected by logic blocks 402 and 404 . This allows any of the inputs to be assigned as a clock and all other inputs as data, or other channels. The trace channels that supply clock(s) and data may supply channels that are skewed. At times there is a need to de-skew clocks when multiple clocks are used. There is also a need to de-skew data inputs to a clock. As shown in FIG. 5 , delay lines 501 are added within the trace receiver of FIG. 4 to provide for alignment of clocks to each other and clocks to data. Skew between data bits and data and clock may drift over time and can change with temperature.
[0056] This skew may be adjusted in a dynamic manner by using two data extraction circuits to accomplish dynamic recalibration. Two separate data paths are created from the same inputs. Both paths are initially calibrated (de-skewed). One circuit is used as the data path after initial calibration. The second circuit is operated in parallel with the first circuit. The skew of the second circuit is adjusted while the channel operates by comparing the data extracted by the two extraction circuits. Once the second circuit is calibrated, its function is changed to the data path with the data path circuit being changed to the calibration path. This process continues at a slow rate as the drift is slow.
[0057] Adaptive calibration of input sampling may be implemented to increase the robustness of the system. At very high data rates, the very small sampling windows may drift because of temperature over long periods of time. Adaptive calibration provides a mechanism to identify approaching marginal setup and hold time situations for the capture circuit creating the data sent to trace channels. Two copies of the data capture logic are used to create a collection and calibration copy of incoming data bits. By capturing the data with the same clocks and data sourced from different delay lines, it is possible to measure whether adequate data setup and hold time margins are being maintained. This is accomplished by alternately moving the delay of the calibration delay line before and after the delay setting of collection delay line. The data values captured by the collection and calibration circuits are compared for mismatches when the collection data is passed to the channels.
[0058] If a mismatch occurs, the setup-time or hold-time margin of the collection data capture is identified. The calibration delay line is adjusted until data comparison errors or detected or the calibration delay line adjustment has reached its extreme. Since the delay lines can be calibrated so that the delay of each tap is known, and thermal drift is measured using an extra delay line, the trace software can adjust the collection delay setting to optimize the sampling point of the collection capture circuit.
[0059] The collection and calibration data streams are compared. The failures are recorded separately for collection data a one and calibration data a zero. A more complete representation of the skew characteristics is provided with this approach. The application software makes adjustments in the collection skew delay when it determines the collection sampling point can be moved to provide more margin.
[0060] In the example shown in FIG. 6 , there are two separate data paths 601 and 602 (A and B). During operation, the skew between data bits may change because of thermal changes. Both Path A and B are calibrated when the channel is activated. When the channel operates, either Path A or Path B is selected to generate channel data 603 . The path not selected processes the same inputs as the path selected. Since the channel is operating, the data pattern is not known. The data extracted from the two channels is compared in block 604 as the delays are adjusted on the path not selected. The optimum sampling points are found for this path. This calibration may take a long time, maybe as much as several minutes. Checks that assure data with ones and zeroes has been passed through the channel are used to assure the path is properly exercised through calibration. Once calibration of the path not selected has been completed, the roles of the two paths are reversed, with the path supplying data to the channel turned into the calibration path at the same time the calibration path is changed to the data source for the channel.
[0061] In order to implement the calibration algorithms, a very long digital variable delay line is required, with minimal distortion. FIG. 7 shows an implementation of such a delay line.
[0062] The delay line has two inputs, normal 701 (PIN_in) and calibration 702 (Calibrate)) as shown in FIG. 7 . Either input or neither input may be selected. When neither input is selected, the delay line may be flushed with a level.
[0063] The calibration input is used to configure the delay line as a ring oscillator while the PIN_in is the signal that is normally delayed. Signal 703 (PIN_out) is the delay line output.
[0064] Two delay elements are shown, one designated as 704 (odd) and another designated as 705 (even). The odd element is controlled by signal 706 (MORE_O) and 708 (LESS_O) control inputs while the even element is controlled by the 707 (MORE_E) and 709 (LESS_E) control inputs. The symmetry of the circuit and input connectivity of the cascaded elements provides extremely low distortion for delays as long as 10 nanoseconds.
[0065] The skew delay is initialized to the minimum when the input is disabled via the MODE codes associated with the input. As shown in FIG. 8 , the delay is increased with the MORE DELAY command 801 , and decreased with the LESS DELAY command 802 . As shown in FIG. 8 , these commands generate MORE_E or MORE_O depending on the last ring control command issued as shown in Table 1. Enable signal 803 enables or disables the control circuit, while Reset signal 804 initializes the delay line settings.
TABLE 1 Command Last Update Current Update MORE MORE_E MORE_O MORE MORE_O MORE_E MORE LESS_E MORE_E MORE LESS_O MORE_O LESS LESS_E LESS_O LESS LESS_O LESS_E LESS MORE_E LESS_E LESS MORE_O LESS_O
[0066] The number of delay elements included in the delay line is controlled by a master slave like shift register mechanism built into the delay element. The Control State of each element is stored locally in an R-S latch. Adjacent cells (even and odd) have different clocks updating these cells. This means the control state latches can be used like the front and back ends of a Master Slave FF. When the cells are connected together they form a left/right shift register. The MORE_O and MORE_E signals are generated by control logic external to the delay line. These signals cause the shift register to shift right one bit. Only half the cells are updated at any one time. A cell that was last updated with a right shift will contain the last one when the shift register structure is viewed from left to right. When the opposite set of cells is updated, a one is moved into the cell to the right of the cell that previously held the last one. This process continues as MORE_E and MORE_O are alternately generated. The circuit looks like a shift register that shifts right filling with ones. The latch implementation is chosen as it is smaller than one done with conventional flip flops.
[0067] The LESS_O and LESS_E signals cause the shift register to shift left one bit. Again, only half the cells are updated at any one time. A cell that was last updated with a left shift will contain the last zero when the shift register structure is viewed from right to left. When the opposite set of cells is updated, a zero is moved into the cell to the left of the cell that previously held the last zero. This process continues as LESS_E and LESS_O are alternately generated. The circuit looks like a shift register that shifts left, filling with zeros.
[0068] When a LESS directive follows a MORE directive, it will update the same set of delay elements as the MORE directive. When a MORE directive follows a LESS directive, it will update the same set of delay elements as the LESS directive. This is shown in Table 1.
[0069] Digital delay lines may be used to provide fixed delays within circuits. These delays may need to be a specific time value. To get a time value, the number of delay elements needed to create the delay must be chosen. This requires the delay of each delay line tap be determined. The ability to determine this delay in a precise fashion is described. It is not sufficient to just turn the delay line into a ring oscillator as minimal setting will create an oscillator that runs too fast to be measured easily.
[0070] In the implementation shown in FIG. 9 , delay lines 901 and 902 are cross coupled. After both delay lines are cross coupled, they are cleared. With one delay line at full length, the other delay line length is changed one tap at a time with the cross coupled delay lines functioning as a ring oscillator. The ring oscillator increments counter 903 once released. The counter is cleared before the delay line is enabled as an oscillator. After a certain period of time the counter is stopped, and the frequency determined. The difference in frequency when a tap is added gives the delay of the delay line tap.
[0071] The same approach may be used with a single delay line as it may be split in half to appear as two delay lines 1001 and 1002 as shown in FIG. 10 . The delays generated by the taps in one section are determined while the other section's delays are held static.
[0072] A trace data source may output trace packets in a width that is not native to the packet. For example, 8 10-bit trace packets may be transmitted as 10 8-bit transmission packets. On the receiver end, the 8-bit transmission packets may be packed into 16-bit, 32-bit, or 64-bit values and stored in trace memory. Any other word with is also acceptable.
[0073] The function that performs the packing of a series of M-bit values into P-bit frames to be stored in memory is called a Packing Unit (PU). In one implementation, the PU stores a number of trace transmission packets in 64-bit words called PWORDs. These trace packets are conveyed to the PU through trace transmission packets that may be a different width than the native trace packet. In this implementation, the PU accommodates trace packet widths of 1 to 20 bits. Other widths are possible. The PU is presented a 48-bit input created from two 24-bit sections. The PU uses the data even valid (DE VALID[n]) and data odd valid (DO VALID[n]) indications to determine when sections of the input need processing. The Packing Unit processes the data frame based on:
Transmission packet width Number of buffer entries in the 48-bit input (0, 1, or 2 transmission packets available) Number of transmission packets processed previously
[0077] A lookup table is used to map the incoming transmission packets in the input frame into the 64-bit words. It is programmed before a trace recording session begins based on the factors noted above. This processing creates 64-bit packed words (PWORDs). These words are then stored in trace memory.
[0078] In this example, the programmable implementation of a packing unit provides for the packing of any transmission width from 1 to 23 bits into PWORDs from 1 to 63 wide. The Packing Unit uses a lookup RAM to define the packing sequence of a series of trace packets that appear in the 48-bit data frame output from one of the AUs. When one works through examples of varied transmission packet and PWORD widths, it is found that the width of the PWORD (less than or equal to 63 bits) determines the programming depth of the lookup RAM.
[0079] The PWORD width is set to an integer multiple of the trace packet width. For a 10-bit trace packet the recording word width is set to 10, 20, 30, 40, 50, or 60 bits. For a 9-bit trace packet width is set to 9, 18, 27, 36, 45, 54, or 63 bits and so forth.
[0080] Let us assume a 4-bit element and a 63-bit recording frame. In this example, the number of recording frames built from the 4-bit input segments is defined by the recording frame width. In other words, the example builds four 63-bit words from 63 4-bit input values. If the input data width is five bits with a memory word width of 63-bits, five 63-bit words are built from 63 five bit input values.
[0081] If the number of words built and the recording word width have a common factor, both numbers can be divided by this factor. In the example of a 10-bit element and a 60-bit recording frame, the common factor is 10 . This means the frame builder can construct one 60-bit word from six 10-bit elements. The relationship between number of words, recording width, and element width is defined by the following equation:
X words can be constructed from Y elements where:
X =Element width/common factor
Y =recording width/common factor
The lookup table must be programmed to the point it repeats (Y locations). A 6-bit register value is used to define the length of the packing sequence before it repeats.
[0083] There is a separate lookup table for each of the 64 recording word bits. These lookup tables specify the input to PWORD bit mapping during the mapping sequence. An extra lookup table output bit is added to the table for bits 21:00 as these bits can straddle one of two PWORDS. The extra bit further defines the PWORD associated with this bit. Bits 62:22 do not need this bit so it is not implemented.
[0084] This results in a 64×7 bit (for PWORD bits 21:00) and a 64×6 bit lookup table (for PWORD bits 62:22). The lookup table specifies the mapping of the input bits (transmission frames) to the PWORDs each clock. The address to these lookup tables begins at zero and is incremented once for each transmission packet processed (0, 1, or 2 each clock). The address generation for a recording channel lookup RAM is defined by the following expression:
if(address+number of elements >=maximum+1){next address=1}
else if(address + number of elements > maximum) {next_address = 0;} else {next_address = address + number of elements;}
[0085] The address generation is handled by a dedicated hardware block that uses the number of valid transmission packets in the input frame and the end of sequence value. The Bit Builders use the address to drive a 64 lookup random access memories (RAMs), one for each of the 63 bits in the PWORD and a 64th to define when PWORDS are completely constructed. The tables within the lookup RAMs select the bit in the 48-bit input that is to be loaded into each PWORD bit. The Multiplexer Lookup RAMs are organized as 16 64×32-bit RAMS (not all bits are implemented), each RAM supplying the multiplexer control for four bits.
[0086] The address generation for the multiplexer control lookup tables increments the address by 0, 1, or 2. The wrap address is set through a register before activating the unit. The address generation begins at zero and progress from there, with the signals indicating available transmission packets driving the address generation.
[0087] While a typical trace receiver records from one input port, bandwidth requirements may dictate the use of multi port input trace receivers capable of recording on multiple channels. Such a multiple port, multiple channel receiver is shown as an example in FIG. 11 , where multiple recording interfaces 1101 - 1102 connect to multiple recording channels 1103 , 1104 , 1105 and 1106 in a selectable manner so that input from each recording interface may be assigned to any recording channel 1107 through 1110 . While FIG. 11 shows a two input, four channel system, there is no limitation on the number of inputs or channels.
[0088] In the interest of increasing bandwidth, recording may be time division multiplexed between the available recording channels. FIG. 12 shows such a trace receiver with multiple recording interface 1201 connecting to multiple recording channels 1202 . A multiple clocks with offsets are used to direct the input data to the desired port.
[0089] Typical trace recorders control trace recording by starting and stopping recording at the source. This is done using gated clocks or an enable. With the advent of more sophisticated transmission methods, the recording control point may be moved to a point past the front end, much closer to the memory interface. The trace receiver front end is synchronized to chip transmission and remains synchronized, while the actual on/off control takes place at the memory interface. This allows the input to continue to operate while the data is either presented to the memory interface or may be discarded without affecting input data synchronization.
[0090] In a typical system, the trace is being recorded by an external device. The trace function may be treated as a peripheral of the device being traced. As shown on FIG. 13 , a trace receiver 1301 is attached to the device 1302 being traced through a trace port 1303 and bus 1304 . The trace device records activity through the trace port 1303 , and may be programmed or the recorded data retrieved through bus 1304 .
[0091] The trace function may be implemented on a development board as a trace chip shown in FIG. 13 . In an alternate implementation the trace capability may be placed on a small add on board.
[0092] It is desirable to be able look at trace information without halting trace recording. It is also preferable to be able to use the trace buffer as a large FIFO for data where the collection rate is less than the rate the host may empty the trace buffer.
[0093] Host transfers to and from trace memory while additional trace data is stored are called Real-time Transfers (RTTs) RTTs can take two forms:
Chasing the most recently stored data (forward reads that progress from the start of buffer toward end of buffer) Snapshot the most recently stored data (reverse reads that progress from the end of buffer toward start of buffer)
[0096] When a RTT is initiated, the command causes the initial memory address for a host memory activity to be dynamically generated from the current trace buffer address. For real-time reads, a read command dynamically generates the initial transfer address. For reads where the read direction is opposite that of store direction, the last stored address is used for the initial read address. For reads where the read direction is the same as that of store direction, the next store address is captured, assuming the buffer is full.
[0097] Trace buffers can be stored or read either forward or backward. Reads while the channel transfer is stopped are called Static Reads. Static Reads provide access to the entire trace buffer contents without the threat of the data being corrupted by subsequent stores. The storing of new data is suppressed by turning the channel off prior to performing a read. The debug software for this type of read specifies the initial transfer address. Static Reads can read the buffer forward or backward.
[0098] Since the trace buffer is circular, a read command can cross the start or end of buffer address. The hardware manages the buffer wrap conditions by resetting the address to the starting buffer address or ending buffer address as required. This may also be done by software.
[0099] When the data is read from the most recently stored data to the least recently stored data, the transfer is assumed to have two components. The first component is created from the current buffer address to the start address and second created from the end buffer address to the current buffer address.
[0100] When the data is read from the least recently stored data to the most recently stored data, the transfer is also assumed to have two components. The first component is created from the current buffer address to the end address and second created from the start buffer address to the current buffer address.
[0101] For the reads from the most recently stored to the least recently stored data, the read processing proceeds as follows. A transfer incomplete error is set if the read terminates before the desired number of words is read. This is caused by a wrap condition occurring on real-time reads (new stores have overwritten data that was to be read creating a discontinuity in old and new data). A no data error is set if no data has been stored in the buffer.
[0102] Care must be taken to detect when the data being read is overwritten by data being stored in the case of real-time transfers. This condition may be detected with a collision counter. This counter detects two overrun conditions:
Data is stored with incrementing/decrementing buffer addresses, data is read with decrementing/incrementing buffer addresses. The number of words stored plus the number of words read is equal to the buffer size. (Peek) Data is stored with incrementing/decrementing buffer addresses, data is read with incrementing/decrementing buffer addresses. The number of words stored minus the number of words read is equal to the buffer size. (Chase)
[0105] These overrun conditions are detected using a Collision Counter. This counter is used to determine the distance between the read and write pointers of the Trace Buffer. When this distance becomes zero, a buffer wrap condition is eminent (some accesses may still be in the pipeline and may not have actually happened yet). Before the Collision Counter has decremented to zero, each word read is valid as it was definitely read before new data is stored in this location. A second Valid Transfer Counter, is incremented for each word read before the Collision Counter decrements past zero.
[0106] The Collision Counter is loaded with the trace buffer size prior to a host transfer. Once the host transfer request is issued, each trace word stored decrements the collision counter. Each word the Transfer Counter stores in the temporary buffer as a result of the channel read request also counts the counter down. When the sum of the two counts decrements past zero, the data read becomes suspect as a wrap condition has occurred or is on the verge of occurring.
[0107] Before the Collision Counter decrements to zero, the Valid Transfer Counter tracks the number of reads that are successful prior to the Collision Counter decrementing past zero. When the transfer completes, Debug Software uses the Valid Transfer Count value to determine how many of the words in read buffer are really valid.
[0108] The chase operation has two components:
Counting the words stored to the buffer and notifying the host The host initiating reads to retrieve the words after being notified
[0111] Once a chase operation is requested, channel stores decrement the Collision Counter and TC stores associated with the channel increment the Collision Counter. Since trace data stores have higher priority, the counter will never count up past the buffer size. An overrun condition occurs when the channel stores decrement the counter past zero. When this occurs, the channel store has stored the entire buffer without the host emptying it. Host reads will read out of order data in this situation.
[0112] At this point another counter, the Store Counter, comes into play. This counter is used to notify the host when a fixed number of words are stored beginning with the point the read request is issued (an interrupt may be generated). The interrupt interval may be made programmable. Once a transfer has been activated, it merely suspends when words are read. A read may be restarted by merely continuing the read from where it paused. Read continues to pause until either terminated with a TERMINATE or INITIALIZE command.
[0113] The overrun condition is detected with the Collision Counter just as with peeks. The counter starts with the buffer size and is decremented by stores and incremented by and TC stores related to the channel read transfer.
[0114] The master slave timing of interfaces coupled with clock insertion delays of devices causes slower performance as the insertion delay comes directly out of the sampling window. As shown in FIG. 14 , programmable delays 1401 and 1403 can be added to the clock and 1402 to the data that allows optimization of timing. The delay may be adjusted dynamically during operation to optimize performance. Scan rates and other transfers may be accelerated by as much as a third when the clock insertion delay is cancelled.
[0115] With traditional trace recorders such as logic analyzers, a time stamp is recorded in parallel with each sample stored into trace memory. Each trace sample corresponded to a cycle of system activity. With today's trace implementations on chip, the trace information does not represent a cycle of system activity. Instead a trace word may be an encoded view of many cycles of system activity. Additionally, on-chip trace export mechanisms may schedule output from multiple sources out of order of execution. This makes the exact arrival of trace information in the receiver imprecise.
[0116] Instead of using the traditional method of adding Time of the Day (TOD) or Time Stamp (TS) information to trace for every sample, this information may be placed in the trace stream itself and represented as a control word. This may be done periodically or at the first empty slot after some period has elapsed.
[0117] By partitioning trace logic to free run while functional logic is clock stepped, the device state of interest may be exported as trace information. When the trace generated by a single functional clock is exported, another functional clock is issued generating more trace information. The functional clock rate is slowed to a rate necessary to export the state of interest.
[0118] The operation of scaled-time simulation is relatively straight forward as shown in FIG. 15 . When a chip is built with trace, the trace logic 1501 is supplied clocks 1502 which are separate from clocks 1503 that normally run the system logic 1504 . This allows the chip to be placed in a special mode where the functional logic is issued one clock. One frame of trace data is generated for each functional clock issued. The valid signal 1505 may be implemented as a toggle, changing state when new information is generated. The Trace Logic 1501 , whose clock is free running, detects a change in state in the valid signal. It processes the trace information presented to it, exporting this information 1506 to a trace recorder. When transmission of this information has created sufficient space to accept a new frame of trace information, the Empty signal 1507 is generated. This causes the clock generation logic to issue another clock to the System Logic. This starts the process over. An optional stall 1508 may be generated by the Trace receiver so it may pace transactions.
[0119] Generally, a trace receiver built with a programmable component, or potentially with another technology (standard cell or ASIC) may, for bandwidth reasons, have a limit as to the width of incoming trace data that can be processed. This is due to the fact that the incoming data rates may outstrip the ability of the receiver to store the data to memory. At times parallel input units may be deployed to capture some portion of the input. The assignment of more than one input channel to a unit can constrain the number of bits that can be processed in parallel. For instance doubling the data rate of the input and using two input channels to process the input in an interleaved fashion, the unit's memory band width or some other factor may require the input width of the incoming data to be constrained to a level than can be handled by the unit.
[0120] The simplest way of dealing with an input capacity problems unit is to place two units in parallel, with each unit recording some portion of the incoming data. In other cases, a wide but slower interface such as a memory bus may be used for recording data, with unused memory BW used to export trace data. In this case the wider interface may also require the use of one or more units for recording.
[0121] FIG. 16 demonstrates an implementation of a distributed width architecture. The system logic 1601 connects to trace channels 1602 , 1603 and 1604 in parallel. Each channel is supplied a set of controls that re identical, and may be as simple as the trace clock. The data 1608 , 1609 and 1610 to be recorded by each unit are different.
[0122] When multiple debug tools are connected to a target system it may be desirable for them to coordinate their activities. Examples of the need for coordination may be during trace compression or other functions where supervision by a master recording unit is required, and a master and one or more slave units must be designated. This coordination may need to be close to the physical connection. The coordination may involve wide trace, coordination of execution control, or global triggers. This coordination may take place in a variety of ways, including direct connections between the respective debug units. An alternate way of coordination may employ a connection through the target connector, wherein the debug units communicate with the connector which in turn implements the required interconnections.
[0123] It may be desirable to expand the trace recording in the deeper dimension. Generally, a trace receiver built with a programmable component, or potentially with another technology (standard cell or ASIC) may, for bandwidth reasons, have a limit as to the amount of incoming trace data that can be processed. In addition the depth of the trace recording may be doubled when the memory space of two or more units is combined. The simplest way of dealing with a trace depth issue is to place two or more units in series, with each unit recording some portion of the incoming data. FIG. 17 demonstrates this architecture. The system logic block 1701 being traced connects to trace unit 1702 , which in turn connects to trace unit 1703 and then to 1704 thus expanding the depth of the trace.
[0124] When memory events are traced, the timing stream is used to associate events with instructions and indicate pipeline advances precluding the recording of stall cycles. These events are traced when the PC is traced. The tracing of data trace values may not be possible concurrent with memory events in some event encoding modes that use both the timing stream and data value.
[0125] When tracing processor activity, three streams are present: timing stream, program counter (PC) stream and data stream. The timing stream has the active and event information, PC stream has all the discontinuity information, and the data stream has all the detailed information. The various streams are synchronized using markers called sync points. The sync points provide a unique identifier field and a context to the data that will follow it. All streams may generate a sync point with this unique identifier. These unique identifiers allow synchronization between multiple streams. When a sync point is generated we will have the streams generated as shown in Table 2. It should be noted that the context information is provided only in the PC stream. There is no order dependency of the various streams with each other. However within each stream the order cannot be changed between sync points.
TABLE 2 Timing stream PC stream Data stream Timing sync point, id = 1 PC sync point, id = 1 Data sync point, id = 1 Timing data PC data Memory Data Timing data Memory Data Timing data PC data Memory Data PC data Timing data Memory Data Timing sync point, id = 2 PC sync point, id = 2 Data sync point, id = 2
[0126] Four events will be sent to trace although at any one time only some of those events may be active. Information is sent to trace to inform how many and which events occurred.
[0127] A timing stream is shown with 0 being active cycle. A “1” however does not represent a stall cycle. Instead it indicates the occurrence of an event.
[0128] Bits [7:0]=00111000 is a timing packet.
[0129] A “1” in the timing stream implies there is at least one event that has occurred. The event profiling information will be encoded and sent to the data section of the data trace FIFO.
[0130] In the generic encoding method, every event that occurs inserts a “1” in the timing stream. If there are multiple events, then it is possible that many “1”s will be inserted in the stream forming an event group. A single “1” can also be an event group by itself. Event groups that occur in a cycle are separated by one or more “0”. The group of “1”s map to the count of events, as outlined in the following table, that occurred with the execute packet. The encoding bits are arranged from MSB to LSB. The total bits required in generic encoding are shown in Table 3. The columns are defined as follows:
#Etrace: Total number of Events being traced; #Events: Total events that occurred in that cycle; Implication: The bits in the stream reflect these events have occurred #Bits: Total bits used for the generic encoding scheme; E0: Event 0; E1: Event 1; E2: Event 2; E3: Event 3.
[0139] Generic encoding should be used when all the events have equal probability of occurring. The user may opt to trace anywhere from 1 event or all four events.
TABLE 3 Line Timing No. #Etrace #Events [MSB:LSB] Data [MSB:LSB] Implication # Bits 1 1 1 1 No bits in data stream E0 1 2 2 1 1 No bits in data stream E0 1 3 1 11 No bits in data stream E1 2 4 2 111 No bits in data stream E0 E1 3 5 3 1 1 0 E0 2 6 1 1 01 E1 3 7 1 1 11 E2 3 8 2 11 0 E0 E1 3 9 2 11 01 E0 E2 4 10 2 11 11 E1 E2 4 11 3 111 No bits in data stream E0 E1 E2 3 12 4 1 1 00 E0 3 13 1 1 01 E1 3 14 1 1 11 E2 3 15 1 1 10 E3 3 16 2 11 01 E0 E1 4 17 2 11 11 E0 E2 4 18 2 11 000 E0 E3 5 19 2 11 010 E1 E2 5 20 2 11 100 E1 E3 5 21 2 11 110 E2 E3 5 22 3 111 10 E1 E2 E3 5 23 3 111 11 E0 E2 E3 5 24 3 111 00 E0 E1 E3 5 25 3 111 01 E0 E1 E2 5 26 4 1111 No bits in data stream E0 E1 E2 E3 4
[0140] The consecutive “is” in the timing stream determine the number of events that are active and being reported. The encoding in the data stream can then be used to determine the exact events that are active in that group. The following table gives and example of the encoding and decoding of the events. The bits are filled in from the LSB. The latter events are packed in the higher bits. It is assumed that the encoding is in generic mode in the following example and all four AEG are active. Therefore only lines 12-26 of Table 3 are referenced for encoding and decoding this data. The same data stream is interpreted differently with reference to different timing streams. The (MSB: LSB) column in the data stored in the FIFO. “Lines” is the lines to be referred to in Table 3 with the current timing data. The table highlights the fact that the interpretation of the data stream changes based on the timing stream.
[0141] In prioritized mode encoding scheme, lesser number of bits are used for some events while some other events may take up more bits. This enables high frequency events to take up lesser number of bits thus decreasing the stress on the available bandwidth. A classic example of this would be misses from the local cache (high frequency), versus misses from the external memory (low frequency).
[0142] A timing stream is shown with 0 being active cycle as before. A “1” however does not represent a stall cycle. Instead it indicates the occurrence of an event.
[0143] Bits [7:0]=00111000 is a timing packet.
[0144] A “1” in the timing stream implies there is at least one event that has occurred. The event profiling information will be encoded and sent to the data section of the data trace FIFO. The priority encoding of this information is based on the following table. The encoding bits are arranged from MSB to LSB.
[0145] The various columns in Table 4 are defined as follows:
#AEG: Total number of AEG active; #Events: Total events that occurred in that cycle; Implication: The bits in the stream reflect these events have occurred; #Bits: Total bits used for the priority encoding scheme; E0: Event from AEG0; E1: Event from AEG1; E2: Event from AEG2; E3: Event from AEG3.
[0154] The consecutive “1's” in the timing stream determine the number of events that are active and being reported. The encoding in the data stream can then be used to determine the exact events that are active in that group. The following table gives and example of the encoding and decoding of the events. The bits are filled in from the LSB. The latter events are packed in the higher bits. It is assumed that the encoding is in prioritized mode in the following example and all four AEG are active. Therefore only lines 12-26 of Table 4 are referenced for encoding and decoding this data. The same data stream is interpreted differently with reference to different timing streams. The (MSB: LSB) column in the data stored in the FIFO. “Lines” is the lines to be referred to in Table 4 with the current timing data. The table highlights the fact that the interpretation of the data stream changes based on the timing stream.
[0155] Table 4 shows the encoding for prioritized compression mode. The prioritized encoding can be used if the user has a mix of long and short stalls, or frequent versus infrequent. This method is skewed toward efficiently sending out a specific event. It is slightly less efficient in sending out rest of the events. This encoding scheme should be used for the case where one event either does not cause any stall, or happens very frequently with very little stall duration. The longer stalls can be put in the group that take more bits to encode. The shorter stalls can be put in a group that takes fewer bits to be encoded. An example of this is L2 miss which is a long stall, versus L1D stall which is a short stall.
TABLE 4 Line Timing No. #AEG #Events [MSB:LSB] Data [MSB:LSB] Implication # Bits 1 1 1 1 No bits in data stream E0 1 2 2 1 1 No bits in data stream E0 1 3 1 11 No bits in data stream E1 2 4 2 111 No bits in data stream E0 E1 3 5 3 1 1 No bits in the data stream E0 1 6 1 11 0 E1 3 7 1 11 11 E2 4 8 2 11 01 E0 E1 4 9 2 111 1 E0 E2 4 10 2 111 0 E1 E2 4 11 3 1111 No bits in the data stream E0 E1 E2 4 12 4 1 1 No bits in the data stream E0 1 13 1 11 0 E1 3 14 1 11 11 E2 4 15 1 11 01 E3 4 16 2 111 01 E0 E1 5 17 2 111 11 E0 E2 5 18 2 111 000 E0 E3 5 19 2 111 010 E1 E2 6 20 2 111 100 E1 E3 6 21 2 111 110 E2 E3 6 22 3 1111 10 E1 E2 E3 6 23 3 1111 11 E0 E2 E3 6 24 3 1111 00 E0 E1 E3 6 25 3 1111 01 E0 E1 E2 6 26 4 1111 100 E0 E1 E2 E3 7
[0156] An example of decoding the streams in the prioritized mode is shown in Table 5. The data stream interpretation changes based on the timing stream.
TABLE 5 MSB:LSB Interpretation Lines Data 001 — — stream Timing 011011110 “1111” in TM => 3 or 4 events active 22-25 example 1 “01” in Data => E0 E1 E2 25 “11” in TM => 1 event active 12-15 ‘0’ left in Data => E1 13 Timing 000111000 “111” in TM => 2 events active 16-21 example “01” in Data => E0 E1 16
[0157] In normal trace, timing stream reflects active and stall cycles. It is also possible to suppress the stall bits, and the stall encoding may instead be replaced with event information. When events are traced, the timing stream is used to associate events with instructions and indicate pipeline advances precluding the recording of stall cycles. This allows the real time tracing of the processor activity without disturbing or halting the processor, and have visibility into the memory system activity with lesser number of trace pins than other approaches.
[0158] A timing stream is shown in where a “0” is an active cycle. In normal encoding a “1” can, therefore represent a stall cycle.
[0159] Bits [7:0]=00111000 is a timing packet.
[0160] Therefore this packet would indicate that there were 3 active cycles, followed by 3 stall cycles, which were then followed by 2 active cycles.
[0161] Instead we can now replace the stall information with event information. The stall information will be suppressed. A “1” now indicates the occurrence of an event. Therefore the above packet can now be interpreted as follows:
[0162] There are 3 active cycles, followed by some event (encoded in this case with 3-“1's”), which is then followed by 2 active cycles.
[0163] The exact encoding is completely user dependent on the protocol implemented. For example if 2 possible events are being traced, they could be encoded as follows:
1−>Event 0 occurred 11−>Event 1 occurred 111−>Event 0 and 1 occurred.
[0167] A timing stream is shown in FIG. 1 where a “0” is an active cycle. In normal encoding a “1” can, therefore represent a stall cycle.
[0168] Bits [7:0]=00111000 is a timing packet.
[0169] Therefore this packet would indicate that there were 3 active cycles, followed by 3 stall cycles, which were then followed by 2 active cycles.
[0170] The exact encoding may also be completely user dependent as to the protocol being implemented. For example if 3 possible events are being traced, they could be encoded as shown in Table 6:
TABLE 6 Timing stream Comment Total bits used 1 Event 0 occurred 1 11 Event 1 occurred 2 111 Event 2 occurred 3 1111 Event 0 and 1 occurred 4 1111 Event 0 and 2 occurred 5 11111 Event 1 and 2 occurred 6 111111 Event 0, 1 and 2 occurred 7
[0171] The user can change the above encoding based on the fact that the likelihood of events alone as well in combination is equal. Then the above method can be changed to a different method shown in Table 7 where a separate stream can hold the reason for the event:
TABLE 7 Timing stream Data Stream Comment Total bits used 1 00 Event 0 occurred 3 1 01 Event 1 occurred 3 1 10 Event 2 occurred 3 11 00 Event 0 and 1 occurred 4 11 01 Event 0 and 2 occurred 4 11 10 Event 1 and 2 occurred 4 11 Event 0, 1 and 2 occurred 4
[0172] The user may be really constrained on the total bandwidth he has, and may potentially wants to profile the events in two runs. In the first run he may have an implied blocking in the events, and thus send out only one event each time. Once he sees his problem area, the user can then focus on just part of his algorithm, enabling higher visibility in that run. Let us say that event 0 has the highest blocking priority. Then the above encoding can be changed to what is shown in Table 8:
TABLE 8 Timing stream Data Stream Comment Total bits used 1 Not used Event 0 occurred 1 11 Not used Event 1 occurred 2 111 Not used Event 2 occurred 3 1 Not used Event 0 and 1 occurred 1 1 Not used Event 0 and 2 occurred 1 11 Not used Event 1 and 2 occurred 2 1 Event 0, 1 and 2 occurred 1
[0173] If we compare the Tables 6, 7 and 8 the total bits that are used in each case is shown in Table 9:
TABLE 9 Comment Table 6 Table 7 Table 8 Event 0 occurred 1 3 1 Event 1 occurred 2 3 2 Event 2 occurred 3 3 3 Event 0 and 1 occurred 4 4 1 Event 0 and 2 occurred 5 4 1 Event 1 and 2 occurred 6 4 2 Event 0, 1 and 2 occurred 7 4 1
[0174] The exact encoding is user dependent, however the point illustrated here is that approach shown in Table 6 works really well for Event 0 if it occurs very frequently, while it takes more bits if events are occurring together. Therefore it gives higher priority for encoding of event 0 and then the priority tapers off for the other events. The approach of Table 7 works really well if all events have an equal likelihood of occurring. It does not take too many bits if all events have equal likelihood of occurring, but loses visibility into the details of the events.
[0175] The exact trade-offs between the various encoding schemes can be made based on the architecture and the variations most users are interested in.
[0176] The timing stream may be used to capture pipeline advances and recording of contributing stall cycles. These stalls are traced when the PC is traced. The trace of data trace values is not allowed concurrent with stall profiling as that stream is used for holding the reasons for the stalls. In a generic mode encoding scheme, all stall groups take up around the same number of bits.
[0177] A timing stream is shown where a “0” is an active cycle. In normal encoding a “1” can, therefore represent a stall cycle.
[0178] Bits [7:0]=00111000 is a timing packet.
[0179] A “1” in the timing stream implies there is at least one contributing stall group active. At the 1st active cycle after that, the last contributing stall that was active (last stall standing) will be encoded and stored. The encoding of this information is based on Table 8. The information is stored in the data part of the data trace FIFO if required. It should be noted that in this mode, tracing of the data values themselves is disabled. In the following table 10 for example implies LSS group 0.
TABLE 10 Generic encoding (Data FIFO) Stall groups Data FIFO (MSB:LSB) Implication 1 not used not used L0 2 1 bit 0 L0 1 L1 3 1-2bits 0 L0 01 L1 11 L2 4 1-3 bits 00 L0 01 L1 11 L2 10 L3
[0180] Generic encoding should be used when all the events have equal probability of occurring.
[0181] In prioritized mode encoding, lesser number of bits are used for some stall groups while some other stall groups may take up more bits. This enables high frequency stall events to take up lesser number of bits thus decreasing the stress on the available bandwidth. A classic example of this would be misses from the local cache (high frequency), versus misses from the external memory (low frequency).
[0182] A timing stream is shown where a “0” is an active cycle. In normal encoding a “1” can, therefore represent a stall cycle.
[0183] Bits [7:0]=00111000 is a timing packet.
[0184] A “1” in the timing stream implies there is at least one contributing stall group active. At the 1st active cycle after that, the last contributing stall that was active (last stall standing) will be encoded and stored. The encoding of this information is based on Table 10. The information is stored in the data part of the data trace FIFO if required.
[0185] It should be noted that in this mode, tracing of the data values themselves is disabled. In the following table 11 for e.g. implies LSS group 0.
TABLE 11 Prioritized encoding (Data FIFO) Stall groups Data FIFO (MSB:LSB) Implication 1 not used not used L0 2 1 bit 0 L0 1 L1 3 1-2bits 0 L0 01 L1 11 L2 4 1-3 bits 0 L0 01 L1 011 L2 111 L3
[0186] Prioritized encoding can be used if there is a mix of long and short stalls. This method is skewed toward efficiently sending out a specific event. It is slightly less efficient in sending out rest of the events. This encoding should be used for the case where one event either does not cause any stall, or happens very frequently with very little stall duration. The longer stalls can be put in the group that take more bits to encode. The shorter stalls can be put in a group that takes fewer bits to be encoded. An example of this is L2 miss which is a long stall, versus L1D stall which is a short stall.
[0187] External events can occur on an active or stall cycle. They need to be marked in the stream to indicate the position of their occurrence. The timing stream can be adjusted to send out that information. Some of the restrictions of this mode are:
[0188] Any packet can be terminated due to an external event.
[0189] The pattern matching and event profiling stream is shown in Table 12. The definition of C 3 and C 5 changes in these modes.
TABLE 12 11 C1 C2 Packet 0 [4:0] 10 C3 C0 Packet 1 [6:0] 10 C4 Packet 2 [6:0] 10 C5 0 0 Packet 3 [4:0] 10 0 Packet 4 [6:0] 10 0 0 0 Packet 5 [4:0]
[0190] The control bits definition for C 0 defining the modes, stays the same as shown in Table 13:
TABLE 13 C0 Function 0 or does not exist Pattern mode 1 Pattern type either type “1010” (A) or “0101” (5)
[0191] Mode 1 uses pattern length matching. The basic mode definition stays the same. It has been enhanced such that the timing packet will be sent out also if the event happens to fall at a pattern boundary. In which case, the event will be reported for the last of the pattern match counts.
[0192] If the event does not occur at a pattern boundary, the current timing pattern packets are rejected. In parallel with it, the 2 nd timing packet with the event information is also rejected.
[0193] In case an event does occur, however the count is small such that C 3 or C 5 are not present the packet containing those bits will be forced out with pattern field being all equal to 0. Therefore the following cases exist:
[0194] In case of C 3 =1, if count of “1's” is Clt6gt16, packet 1 will still be forced to come out, however it's value will be 0.
[0195] In case of C 5 =1, if count of “0's” is Clt7, packet 3 will still be forced to come out, however it's value will be 0.
[0196] If there is no count of “1's”, then the count of “0's” case reverts back to case A.
[0197] The interpretation of bits C 1 , C 2 , C 4 stay the same as before for pattern mode (C 0 =0). The definition of the additional control bits C 3 and C 5 is shown in Table 14:
TABLE 14 Bit Value Condition Function C3 0 There is no event after these ‘1’ 1 There is an event after these ‘1’ C5 0 There is no event after these ‘0’ 1 There is an event after these ‘0’
[0198] Mode 2 is defined by a fixed pattern of “10” or “01”. In this mode, in case of the occurrence of an event, both the packets will always be sent to ensure that C 3 is forced to come out. This is regardless of the count value itself (which is above a basic minimum as outlined before). Therefore this mode works exactly like before.
[0199] Mode 3 shows standard timing packets. In this mode, if an event occurs, the 2 continuation packets are followed. This contains the timing index into the timing stream. The event will force this timing packet to come out. If timing index is 0, it indicates that the last valid bit in the last timing packet is a “0”. If this bit is a “1”, it implies that the last valid bit in the last timing packet is a “1”.
[0200] Depending on the MSB of the “11” timing packet, this packet has to be encoded differently. If the MSB is a “0”, it implies that C 1 =“0”. This indicates that the next packet is a continuation of count of “1's”. In the next packet, C 0 =1 puts it is A/5 mode. However, the additional continuation packets breaks it out of the A/5 mode and puts it in external event profiling, standard timing packet. This is shown in table 15:
TABLE 15 11 Timing Bit7=0 Timing Bits [6:0] 10 C3 =1 C0 =1 Reserved = “000000” 10 Reserved[6:0] Timing index Bit
[0201] If the MSB is a “1”, it indicates C 1 =“1”. Therefore the next packet is a count of “0's”. Forcing C 4 =“0” indicates that the last continue packet is a continuation of count of ‘0's”. A “1” next to C 5 in the last packet, breaks it out of pattern match mode and puts it in standard timing external event profiling mode shown in Table 16.
TABLE 16 11 Timing Bit7=1 Timing Bits [6:0] 10 C4 =0 Reserved = “000000” 10 C5=1 1 Reserved[4:0] Timing index Bit
[0202] The events are inserted into the data stream when they occur.
[0203] The decoder, on finding an event in the timing stream, looks at the next event reported in the data stream, thus identifying with complete precision, the exact cycle and PC at which the external event occurred.
[0204] Events asynchronous to the processor can arrive at any time, even during stall cycle. These events can impact the state of the processor completely and it is essential to understand their timing.
[0205] The timing stream may used to capture pipeline advances and recording stall cycles. Timing stream can be in standard or compressed format. These stalls are traced when the PC is traced. The trace of data trace values is not allowed concurrent with external event profiling as that stream is used for holding the reasons for the external event.
[0206] A timing stream is shown where a “0” is an active cycle. In normal encoding a “1” can, therefore represent a stall cycle.
[0207] Bits [7:0]=11111000 is a timing packet.
[0208] Bits [9:0]=11 implies a timing packet let us say.
[0209] If an external event occurred during a stream of “1's”, let us say after 3 stall cycles, the above packet could be encoded as shown in Table 17:
TABLE 17 Timing Control Bits bits [9:8] [7:0] Comment 11 00111000 “11” control bits reflect the start of a timing packet Timing bits [7:6] are not valid but flushed bits 10 00000001 “10” packet presence reflects that there is an external event timing bits [7:1] are not valid timing bit[0] indicates the last valid bit that was present in the timing packet 00111000
[0210] To debug control flow, user needs to know which of the predicated instruction executed, and which ones did not. For this the predication event is enabled. While PC trace is on, and the trace is in predication event profiling mode, the trace hardware captures the predication events in each cycle. It inserts this information in to the data logs, and does a right shift such that the data gets compact. The trace window will eventually close, either because tracing has been turned off, or because a periodic sync point is generated, to reset the window. In either of these two cases, the data log may be incomplete, fully packed, or just overflow into the next packet. The issue is, how does the decoder understand the fact that not all, or all the bits, are valid in the data log.
[0211] Predication information comes from the CPU to the trace hardware. As this information gets packed in the data logs the decoder can do one-to-one matching of the PC addresses and the predication events, based on the object file. Therefore as shown in Table 18:
TABLE 18 Bits put in PC data Data Data Value of register Address Predicates used in code log Byte0 Byte1 bits Start of window P0 [A0], [A1] 10 ------10 A0 = 0, A1 = 1 P1 [B1], [A1] 11 ----1110 B1=1, A1=1 P2 [B2] 0 ---01110 B2=0 P3 [B2][B1][B0[A2][A1][A0] 010110 11001110 -----010 B2=0, B1=1, B0=0 close of window A2=1, A1=1, A0=0 P4 Not traced
The packets seen by the decoder will be: Start sync point with PC address; Aligning data sync point; 11001110 Data Byte 0 ; 00000010 Data Byte 1 ; and End sync point with PC address P4.
[0218] Based on the object file, the decoder can easily reverse engineer this and derive Table 19:
TABLE 19 Comment Data bits used Values assigned P0 uses 2 predication bits 00000010 11001110 A0 = 0, A1 = 1 P1 uses 2 predication bits 00000010 11001110 B1 = 1, A1 = 1 P2 uses 1 predication bits 00000010 11001110 B2 = 0 P3 uses 6 predication bits 00000010 11001110 B2=0, B1=1, B0=0 A2=1, A1=1, A0=0 Ignores upper bits of the 00000010 11001110 data log
[0219] Since the decoder knows from the object file that how many bits need to be discarded, there is no additional hardware required to send out an index into the data log. Similarly, the bandwidth is saved as well, as no bits are sent to indicate that how many bits in the data log are valid.
[0220] To enable visibility, stalls, and other events are embedded in the timing stream along with the active cycles. The PC stream has PC discontinuity information. The data logs are used for storing the reason for the stall or the event as the case may be. This information stored is not fixed width, but is anywhere from 1+number of bits based on various factors.
[0221] The details for the stall or event come to the trace hardware from various sources. As this information gets packed in the data logs the decoder can do one-to-one matching of the events reported in the timing stream and the events in the data logs, as well as the PC based on the timing advances. In the data log detail, each individual detail is separated by a “0”. Therefore in the following example, let the packets seen by the decoder be:
Timing sync point; Start sync point with PC address; Aligning data sync point; 01000100 Timing packet1;
[0226] 00010101 Timing packet2;
11001110 Data Byte 0 ; 00000010 Data Byte 1 ; Timing sync point; and End sync point with PC address P4.
[0231] Based on the timing data, the decoder can easily reverse engineer this and derive Table 20:
TABLE 20 Events detected Timing bits used Data bits used Event 0 01000100 11001110 Data Byte 0 00010101 00000010 Data Byte 1 Event 1 01000100 11001110 Data Byte 0 00010101 00000010 Data Byte 1 Event 2 01000100 11001110 Data Byte 0 00010101 00000010 Data Byte 1 Event 3 01000100 11001110 Data Byte 0 00010101 00000010 Data Byte 1 Event 4 01000100 11001110 Data Byte 0 00010101 00000010 Data Byte 1 Ignores upper bits 11001110 Data Byte 0 of the data log 00000010 Data Byte 1
[0232] Since the decoder knows from the timing packets how many events need to have details, there is no additional hardware required to send out an index into the data log. Similarly, the bandwidth is saved as well, as no bits are sent to indicate that how many bits in the data log are valid.
[0233] A software pipeline loop is different from other discontinuities, because it repetitive. It also has other issues like the next iteration can start before the first one is complete. Furthermore, it is possible to reload it, and may or may not be reloaded. It can terminate due to an exception. It can be drained in the middle for an interrupt.
[0234] The rules for SPLOOP tracing are as follows. If SPLOOP starts do not send out any information at that point. The SPLOOP information can be inferred from the End of SPLOOP packet. If the SPLOOP is skipped, send out information indicating that.
[0235] If the SPLOOP is skipped and executed as NOPS the following packet “NoSP” will be sent out if tracing is already on. If the tracing is started or ended in the skipped SPLOOP, this information will be sent out via special control bitsIn case of SPLOOPD, the condition is always evaluated as true therefore this packet can never be sent in the normal operation.
[0236] If the SPLOOP is not skipped, the SPLOOP will be reported at start of the first cycle of the epilog stage and not the final stage of epilog. In case of early exit, the SPLOOP is still reported when the epilog starts, regardless of the prolog still loading. The iteration count (IC) is the count since the last time SPLOOP information was sent, or the position in the SPLOOP if it is a part of a periodic or start/end sync point. Since the periodic counter is 12 bit wide, the IC can be a maximum of 12 wide for ii=1.
[0237] The periodic SPLOOP marker (PerSP) will be sent out along with any PC Sync point if the SPLOOP is active. There can be no other information that can be sent between the periodic sync point and the PerSP packet. PerSP will be also sent if data log is being traced and data trace is on by itself.
[0238] This packet sends out the exact position in the SPLOOP. It contains the following information:
In the prolog, it sends out the absolute iteration count. There are a maximum of 7 packets that may have to be sent out. In the kernel, it just sends out the information that the SPLOOP is in the kernel. The continue packet for the count will not be sent out. The count bits will be reserved to “000” in this case. This also contains the address of the SPLOOP itself, if the PerSP is being sent out in a reload or a return from interrupt SPLOOP. This is due to the fact that the address on the PC bus coming from the CPU may have an address completely remote from the SPLOOP itself. It may have changed due to a branch in the code fetched from the memory during the previous drain. The PC address in the PerSP can be sign extended.
[0242] The periodic SPLOOP marker (PerSP) will be sent out along with any PC Sync point if the SPLOOP is active. There can be no other information that can be sent between the periodic sync point and the PerSP packet. PerSP will be also sent if data log is being traced and data trace is on by itself.
[0243] When multiple activities are being profiled, there is the possibility of data corruption due to excessively large amounts of trace data being collected. This may be reduced by forming a logical or of a number of the signals being profiled to determine the area of software of interest. Then a second run may be performed for only the limited parts of the applications which have issues, turning on full visibility this time.
[0244] Trace gives full visibility in to the processor activity. One can have a good insight in to what an application is doing, even without an object file. Trace can be turned on and off based on cycle count, giving some information about the secure code. It is imperative that this information should be blocked.
[0245] It is assumed that the code will switch to secure code via an exception only. All PC and data trace will be turned off during secure code. This will occur regardless of trace being in standard trace mode or event profiling mode. Timing, if on, will switch to standby mode.
[0246] On return from the secure code, the switches that were already on will switch back and turn on.
[0247] Once in secure code, none of the streams can be switched, regardless of the streams being currently disabled. TEND is the only trigger that will have any impact in secure code. The address reported in the end sync point, caused by the TEND, will be the address 0×01. Similarly, a TRIGGER in the secure code will also report a sync point with the address of 0×01.
[0248] Since the PC address in the sync point is an illegal address of 0×01, therefore this information is sufficient to indicate an end sync point was caused in secure code.
[0249] Table 21 shows the sync types can occur. In all cases, data trace being on or off is optional. In case of TEND, when the code switched back to insecure code, the streams will not switch back on.
TABLE 21 Stream Event Sync Type PC off, TM off — — PC on, TM off Switch to secure code End PC on, TM off TEND End PC on/off, TM on Switch to secure code Stand by mode PC on/off, TM on TEND End Stand by mode TRIGGER Trigger
[0250] When tracing of data is enabled, the volume of data increases tremendously. The trace output at times cannot keep up with the volume of data that is being generated. There are unique IDs embedded in each of the streams, PC, timing and data to maintain synchronization between them, even though the data logs themselves recover from the corruption, reset the compression map, however, the decoder has no idea, what is the ID of the logs, because multiple IDS may have been lost in the corruption. Therefore, the decoder has to wait till it sees the next set of IDs for PC, timing and data, before it can start decoding again.
[0251] A solution is to force the insertion of a data sync point along with the first log after corruption, even if it means repeating the sync point id. The decoder will immediately know the id of the logs after corruption and will not have to throw away the logs, till it comes across the next sync id.
[0252] The traditional technique for sending out timing data is by sending out one bit for every active or stall cycle. Typical DSP applications have been found to have specific patterns in the active and stall cycles. Some examples of this would be cross-path stalls, bank conflicts, writes buffer full etc. Instead of sending out the actual pattern, it is possible to send control bits in the stream marking these specific patterns followed by the count of the total times the pattern occurred.
[0253] In a timing packet a “0” is an active cycle and a “1” is a stall cycle. Table 22 shows how timing packets can have alternate meaning based on the fact that the first timing packet is followed by not a “11” kind of control bits, but some other bits (in this example “10” bits.
TABLE 22 Bits [7:0] Packet Bits [9:8] (Timing Number (Control Bits) Data bits) Comment 1 11 00111000 Timing data of packet 1 is raw 2 11 01000100 timing bits where a ‘1’ is a stall cycle, while a ‘0’ is an active cycle 1 11 00111000 Bits [7:0] of packet 1 is now no 2 10 01000100 longer raw timing data, but could be more control bits if desired, or reflect a different type of data altogether.
[0254] The trace stream sends out CPU register information in the trace stream under the following circumstances:
There is a change in the CPU register and any one of the streams are enabled; There is a sync point due to a stream being enabled, or a periodic sync point and the CPU register is a non-zero value. The sync point will be sent out first followed by the CPU information. In this case the instruction count information will not be sent out.
[0257] PC Trace includes the PC values associated with overlays. Without information about the overlays installed at the time the PC trace of overlay execution takes place, it is not the actual overlay being executed cannot be ascertained merely form PC trace information.
[0258] Additional information is needed in the trace stream to identify an overlay whose execution of code in a system where overlays or a Memory Management Unit are used. The method for exporting information in addition to the PC is shown in FIG. 18 . The block diagram shown in FIG. 18 can be used to add any information type to the PC export stream 1806 . In the case of PC Trace, additional information is added when the memory system contents is changed. Information describing the configuration change is inserted into the export stream 1806 by placing this information in a message buffer 1802 . A request to insert a message in the stream is asserted by signal 1803 when the complete message is placed in the buffer 1802 . Once this request is asserted all words of the message are sent consecutively to the Trace block 1805 and then to the trace stream 1806 . As long as a message word is available for output, it becomes the next export word as the output of message words is continuous. Loading the message records the number of message words to be output.
[0259] In a system where power and performance are very important, it is important to allow the developer to understand what system conditions are causing execution to stall. The concept of last stall standing allows the recording of information about what system events or event groups are causing the stall of system execution. The number of stalls attributable to the offending stall condition may also be recorded. FIG. 19 shows an implementation of this concept.
[0260] Each occurrence of the ready signal 1901 causes the register 1902 contents to be encoded and exported by block 1903 provided the following conditions are true:
The last stall standing function is enabled; One of the sets had an element active the last clock cycle; No stall condition exists this cycle; and Ready has been inactive a sufficient number of cycles to satisfy the threshold if a threshold is implemented in block 1905 .
[0265] Stalls conditions can be assigned to any set or no set. It is therefore possible to move the priority of any stall condition higher or lower using priority encoder 1904 .
[0266] Last stall standing operation provides a label associated with each stall period that exceeds a specified threshold as determined in block 1905 . This allows one to filter out some stall busts, i.e. to preserve trace bandwidth.
[0267] Events may be recorded as multi-bit values representing the events or encoded representations of the bits. These multi bit values may vary in width and do not fit the form used for native storage. These event representations can be packed in the format normally used for representing trace data, allowing the sharing of hardware with data trace, including all compression functions.
[0268] To provide state accurate simulation, the functional logic itself can be used as a simulation platform. Trace is used to output the internal machine state of interest. Trace is recorded by a unit that controls the pace of trace generation with a pacing signal.
[0269] As shown in FIG. 20 the functional logic is placed in self simulation mode. When the trace logic 2002 does not have any more data to output it changes the state of advance signal 2003 . The clock generator 2004 detects this state change and issues one gated clock 2005 to the functional logic. This creates a new CPU state and causes change 2006 to toggle to the trace logic. The trace logic notes the state change in change 2006 and it exports the state presented to it. Once it completes it changes the state of advance 2003 and the process begins anew.
[0270] Predication trace is valuable as it details control decisions. A means to support predication trace must minimize the trace bandwidth required to record predication. Predication may involve a number of terms that can be selected for use as the predication value. Not all predication terms are used in these situations. The terms that will be used are defined by the instruction executing. Only the terms used are exported with the unused terms discarded.
[0271] Trace data is generally routed to a single recording channel and is not packaged. When packaging of trace from different sources is added, routing information must be provided as packaging is specific to an output channel (destination). In a complex system being traced, there can be multiple trace destinations. With multiple trace data sources, each source may be routed to one of n destinations. A novel way to determine the export routing is to have the source provide the destination of its data to trace merge logic along with its source ID and data. Packing logic uses this routing information to pack the data for delivery to the desired destination, packing this data with other data destined for the same destination.
[0272] An alternate way to derive the routing information is to have the source ID to drive a look-up table to determine the destination of the data. This destination information from the look-up is used by the packaging unit to prepare the data for export to one of n destinations.
[0273] The internal trace buffers used to record trace information to be exported are, in the previous art designed to record the information, and then have this information read by a host. In order to meet bandwidth requirements, the internal buffer may be operated as a FIFO in the current implementation.
[0274] Bandwidth requirements for trace export can be high, and may require dedicated trace pins on the package. These pins may be reduced or eliminated, and the bandwidth requirements reduced by exporting the trace data to the application memory using the standard application busses instead of using dedicated trace pins. | Multiple debug tools interacting with the same target system must be interconnected to allow communication between the debug tools. This interconnection may be accomplished by connections on the motherboard, interconnecting at the connector level, or direct connections between the applicable debug tools. | 6 |
This is a continuation of application Ser. No. 661,471 filed Feb. 26, 1976, now abandoned.
FIELD OF INVENTION
The present invention pertains to the manufacture of free flowing detergent builder beads capable of carrying relatively large amounts of various surface active agents and other liquid or semisolid materials. Specifically the invention provides a method for producing spray dried base builder beads that are oversprayed with synthetic detergents such as nonionics, anionics and cationics or combinations thereof to produce granular detergent formulations of improved detergency and solubility and that contain relatively large amounts of the synthetic detergent component while retaining free flowing properties. The invention is particularly useful in providing a granular free flowing detergent having a high content of nonionic synthetic organic detergent. As used herein the terms overspray and post spray are equivalent and should be taken to include any suitable means for applying a liquid or liquifiable substance to the spray dried base builder beads of the invention, including, of course, the actual spraying of the liquid through a nozzle in the form of fine droplets.
BACKGROUND AND PRIOR ART
Typically, nonionic synthetic detergents having the desired detergency properties for incorporation into commercial granular detergent products, such as laundry powders, are thick, viscous, sticky liquids or semi-solid or waxy materials. The presence of these materials in a detergent slurry (crutcher mix) prior to spray drying in amounts greater than about 2-3 percent by weight is impractical since the nonionic synthetic detergent will "plume" during spray drying and a significant portion can be lost through the gaseous exhaust of ths spray drying tower.
The art has recognized the application of nonionic synthetic detergents of this type to various particulate carrier bases to produce relatively free flowing granular products that can be used as household laundry products. Representative patents containing teachings and disclosures of methods for producing granular free flowing laundry detergents by post spraying a nonionic synthetic organic detergent onto a spray dried particulate product containing detergent builders include; among others: Di Salvo et al U.S. Pat. Nos. 3,849,327 and 3,888,098; Gabler et al U.S. Pat. No. 3,538,004; Kingry U.S. Pat. No. 3,888,781; and British Pat. No. 918,499 (Feb. 13, 1963). The prior art in this regard is typified by post spraying from about 1 to a maximum of 10 percent by weight of a nonionic synthetic detergent onto a spray dried bead that contains a substantial proportion of a surface active agent such as anionic detergents, filler materials, and detergent builders.
Further, certain desirable ingredients for detergent formulations such as cationic surface active agents that provide fabric softening properties and optical brighteners, bluing agents and enzymatic materials cannot be spray dried because of thermal decomposition. Such materials can be incorporated into a granular detergent according to the invention by post spraying them onto the spray dried base builder beads either alone or in addition to a nonionic detergent or other suitable ingredients.
SUMMARY OF THE INVENTION
In one specific aspect the invention provides a method for producing spray dried builder beads that are suitable for carrying relatively large amounts i.e. about 2 to about 40 percent by weight, preferably from about 12 to about 40 percent, of various detergent ingredients such as anionic, nonionic, cationic surface active agents, optical brighteners, bluing agents, soil release agents, antiredeposition agents etc. and mixtures thereof. The post added detergent ingredients are applied in liquid form onto the base beads by any suitable means, preferably by spraying in the form of fine droplets from a spray nozzle while the beads are being agitated. In its broadest sense the invention contemplates the post addition or application of any liquid or liquifiable organic substance, that is suitable for incorporation into a laundry detergent formulation, onto spray dried base builder beads comprising inorganic detergent builders.
The new base builder beads of the invention are characterized by spherical or irregularly shaped particles or beads comprising from about 45 to about 80 percent phosphate builder salt, from about 5 to about 15 percent alkali metal silicate solids and from about 5 to about 15 percent water. From about 30 to about 60 percent of the alkali metal phosphate component is hydrated in the presence of the alkali metal silicate component and the remainder is in anhydrous form. The beads can be classified as solid as opposed to the hollow beads typical of spray dried powders, and have a porous, sponge-like outer surface and a skeletal internal structure.
According to the invention, the post sprayed ingredients are primarily disposed internally of the outer surface of the particles and is minimally present on the outer surface of the particles. The resulting product is free flowing and without a significant tendency to stick together or agglomerate. Desirably less than about 10 percent by weight of the oversprayed material is present on the outer surface of the final beads.
The free flowing ability of a granular or particulate substance can be measured in relation to the flowability of clean dry sand under predetermined conditions, such as inclination with the horizontal plane, which is assigned a flowability value of 100. Typical spray dried detergent powders as presently available on the market have a relative flowability of about 60 in relation to sand i.e. 60 percent of the flowability of sand under the same conditions. Surprisingly the new granular product of the invention has a flowability value of at least about 70 in relation to clean dry sand under the same conditions and up to about 90 or more.
The new base builder beads according to the invention can be further characterized as follows:
Particle size distribution: at least about 90% by weight passing through a 20 mesh screen (U.S. series) and being retained on a 200 mesh screen (U.S. series)
Density (Sp Gravity): 0.5-0.80
Flowability: 70-100
The novel base beads of the invention can be produced as follows:
A first quantity of a hydratable alkali metal phosphate builder salt is hydrated in the presence of a second quantity of an alkali metal silicate; the weight ratio of the first quantity to the second quantity being from about 1.5 to about 5. The hydrated phosphate and silicate are mixed in an aqueous medium at a temperature of at least about 170° F. with a third quantity of anhydrous alkali metal phosphate builder salt to form a slurry, or crutcher mix; the weight ratio of the first quantity to the third quantity being from about 0.3 to about 0.7. Various other detergent ingredients i.e. builders such as carbonates, citrates, silicates, etc., and organic builders, and surface active agents can be added to the crutcher mix after the hydration step. According to the invention it is preferred that the presence of organic surface active agents in the crutcher mix be limited to less than 2 percent of the solids present and most preferably that the crutcher mix be free from organic surface active agents. The crutcher mix is agitated and maintained at a temperature from about 170° F. to about 200° F. to prevent any significant hydration of the third quantity of anhydrous phosphate builder salt. Sufficient water is present in the slurry so that the crutcher mix contains from about 40 to about 55 percent solids. Adjuvants such as brighteners, bluing, or other minor ingredients may be present in the crutcher mix if necessary or desirable or may be post added to the spray dried beads.
The crutcher mix is then pumped to a spray tower where it is spray dried in the conventional manner. The spray drying may be performed in a countercurrent or co-current spray drying tower using an air inlet temperature from 500° to 700° F. and a spray pressure from about 200 psig to about 1000 psig. The spray dried product comprises a large plurality of particles having a novel sponge-like structure as opposed to the hollow structure that typically results from spray drying a detergent crutcher mix.
In one of its preferred aspects the invention provides a particulate detergent product that is suitable for the home or commercial laundering of textile materials. The new detergent product is characterized by having a nonionic synthetic organic detergent content of from about 10 to about 40 percent, preferably from about 12 to about 30 percent by weight and the absence of filler materials such as alkali metal sulfates that are commonly present in spray dried detergent powders to obtain high spray drying rates. The new granular detergent can be used by itself as a complete laundry detergent or various ingredients such as perfumes, coloring agents, bleaches, brighteners, fabric softeners, etc. can be added.
The method for producing the new granular detergent includes the steps of first providing a large plurality of base builder beads having the above mentioned physical characteristics. The nonionic synthetic detergent is then applied on to the spray dried builder beads while they are being agitated, in an amount of from about 10 to about 40 percent by weight of the final product. Nonionic synthetic detergent impregnates the pores or openings on the surface of the beads and passes into the skeletal internal structure; an insignificant amount if any, of the nonionic component remaining on the bead surface. The minimal amount of nonionic detergent on the outer surface of the beads is evidenced by the substantially similar flowability rates obtained for the beads before and after they are sprayed with the nonionic component. A similar process is used to apply other post added ingredients, as disclosed herein, to the spray dried detergent builder beads.
BRIEF DESCRIPTION OF THE DRAWING
The drawing accompanying this application consists of two photomicrographs of a spray dried builder bead or particle according to the invention prior to being post sprayed.
FIG. 1 shows the major portion of a bead according to the invention magnified 200 X.
FIG. 2 shows a cut away portion of the bead of FIG. 1 magnified 2000 X.
DESCRIPTION OF PREFERRED EMBODIMENTS
As shown in the drawing the new base builder beads comprise solid particles of irregular configuration that have a sponge-like, porous outer surface and a skeletal internal structure. In contrast, conventional spray dried detergent beads such as those currently available on the consumer market typically comprise spherical particles or beads with a substantially continuous outer surface and a hollow core.
The new base builder beads comprise by weight, from about 45 to about 80 percent phosphate builder salt, preferably from about 50 to about 70 percent; from about 5 to about 15 percent alkali metal silicate solids, and from 5 to about 15 percent water. According to a specific aspect of the invention, a substantial portion of the builder salt component of the base beads is the product of hydrating to a maximum degree, typically to the hexahydrate form, from about 30 to about 60 percent of the phosphate builder salt component in the presence of alkali metal silicate. In further accordance with this specific aspect of the invention, the weight ratio of hydrated phosphate builder salt to alkali metal silicate in both the crutcher mix and base beads is from about 1.5 to about 5, preferably about 2 to about 4, and the weight ratio of hydrated phosphate builder salt to anhydrous builder salt in the crutcher mix and base beads is from about 0.3 to about 0.7, preferably about 0.4 to about 0.6.
In its presently preferred form, the crutcher mix of the invention contains only inorganic detergent builders and water and is free from organic surface active agents. Most preferably the crutcher mix is also free from filler materials such as sodium sulfate.
The alkali metal phosphate builder salt component of the new base builder beads is chosen from the group of phosphate salts having detergent building properties. Examples of phosphate builder salts having detergent building properties are the alkali metal tripolyphosphates and pyrophosphates of which the sodium and potassium compounds are most commonly used. These phosphates are well known in the detergent art as builders and can either be used alone or as mixtures of different phosphates. More specific examples of phosphate builder salts are as follows: sodium tripolyphosphate; sodium phosphate; tribasic sodium phosphate; monobasic sodium phosphate; dibasic sodium pyrophosphate; sodium pyrophosphate acid. The corresponding potassium salts are also examples along with mixtures of the potassium and sodium salts.
The alkali metal silicate component of the crutcher mix is supplied in the form of an aqueous solution preferably containing about 40 to 60 percent by weight typically about 50 percent silicate solids. Preferably the silicate component is sodium silicate with an Na 2 O:SiO 2 ratio from about 1:1.6 to about 1:3.4 preferably from about 1:2 to about 1:3, and most preferably about 1:2.4.
The overspray ingredients or components can be any liquid or material capable of being liquified that is suitable or desirable for incorporation into a detergent formulation. Suitable materials for overspraying onto the spray dried builder beads of the invention in amounts from about 2 to about 40 percent by weight include, but are not limited to surface active agents, antiredeposition agents, optical brighteners, bluing agents, enzymatic compounds etc.
Suitable surface active agents include anionic and nonionic detergents and cationic materials. Typical anionic materials include soap, organic sulfonates such as linear alkyl sulfonates, linear alkyl benzene sulfonates, and linear tridecyl benzene sulfonate etc. Representative cationic materials are those having fabric softening or antibacterial properties such as quaternary compounds. These last mentioned cationic materials are particularly suitable for post addition since they might thermally decompose if spray dried as part of a crutcher mix. Examples of quaternary compounds having desirable fabric softening properties are distearyl dimethyl ammonium chloride (available from Ashland Chemical under the trademark Arosurf TA100) and 2-heptadecyl-1-methyl-1-[(2-stearoylamido) ethyl] imidarzolinium methyl sulfate (also available from Ashland Chemical Co. under the trademark Varisoft 475).
The nonionic surface active agent component of the new formulation can be a liquid of semi solid (at room temperature) polyethoxylated organic detergent. Preferably, these include but are not limited to ethoxylated aliphatic alcohols having straight or branched chains of from about 8 to about 22 carbon atoms and from about 5 to about 30 ethylylene oxide units per mole. A particularly suitable class of nonionic organic detergents of this type are available from the Shell Chemical Company under the Trademark "Neodol". Neodol 25-7 (12-15 carbon atom alcohol chain; average of 7 ethylene oxide units) and Neodol 45-11 (14-15 carbon atom chain; average of 11 ethylene oxide units) are particularly preferred.
Another suitable class of ethoxylated aliphatic alcohol nonionic synthetic detergents are available under the Trademark "Alfonic" from Continental Oil Company, particularly Alfonic 1618-65, which is a mixture of ethoxylated 16 to 18 carbon atom primary alcohols containing 65 mole percent ethylene oxide.
Further examples of nonionic synthetic organic detergents include:
(1) Those available under the Trademark "Pluronic". These compounds are formed by condensing ethylene oxide with a hydrophobic base formed by the condensation of propylene oxide with propylene glycol. The hydrophobic portion of the molecule which, of course, exhibits water insolubility, has a molecular weight of from about 1500 to 1800. The addition of polyoxyethylene radicals to this hydrophobic portion tends to increase the water solubility of the molecule as a whole and the liquid character of the product is retained up to the point where the polyoxyethylene content is about 50 percent of the total weight of the condensation product.
(2) The polyethylene oxide condensates of alkyl phenols, e.g., the condensation products of alkyl phenols, having an alkyl group containing from about 6 to 12 carbon atoms in either a straight chain or branched chain configuration, with ethylene oxide, the said ethylene oxide being present in amounts equal to 5 to 25 moles of ethylene oxide per mole of alkyl phenol. The alkyl substituent in such compounds may be derived from polymerized propylene, dirsobutylene, octene, or nonene, for example.
Other surface active agents that may be suitable are described in the texts, "Surface Active Agents and Detergents", Vol. 11, by Schwarz, Perry and Berch, published in 1958 by Interscience Publishers, Inc., and Detergent and Emulsifiers, 1969 Annual by John W. McCutcheon.
A particularly preferred detergent formulation according to the invention comprises from about 12 to about 30 percent nonionic synthetic organic detergent, most preferably of the polyethoxylated aliphatic alcohol type, oversprayed onto spray dried base builder beads produced according to the method of the invention.
The following examples describe specific embodiments that are illustrative of the invention: (all percentages are by weight unless otherwise specified).
EXAMPLE 1
An aqueous slurry of the following ingredients is prepared.
______________________________________ Amount, Percent (based on totalIngredient crutcher mix)______________________________________Sodium tripolyphosphate powder (anhydrous) 14.5Sodium silicate solids (Na.sub.2 O/SiO.sub.2 = 2.4) 7.6Water 28.6______________________________________
The slurry is brought to a temperature of about 140° F. and mixed well to form the hexahydrate phosphate salt and is subsequently heated to 190° F. and maintained between 190° F. and 200° F. to prevent hydration of the next to be added phosphate ingredient.
The following ingredients are then added to the aqueous slurry at 190° to 200° F. to form a crutcher mix.
______________________________________ Amount Percent (based on totalIngredient crutcher mix)______________________________________Sodium tripolyphosphate powder (anhydrous) 28.3Water 21.0______________________________________
The crutcher mix contains from about 45 to about 50 percent solids by weight.
The crutcher mix is supplied to a countercurrent 8 foot high spray drying tower and is sprayed at a manifold temperature of 180° F. and a pressure of 600-900 psig using a Whirljet 15-1 or Fulljet 3007 spray nozzle.
An air inlet temperature (T 1 ) of about 600° F. is used in the spray tower.
The spray dried base beads produced have the following properties and are similar in internal structure and outer surface characteristics, to the bead shown in FIG. 1.
______________________________________Base Bead Properties______________________________________Moisture 10%Tripolyphosphate (Sodium salt) 77%Silicate Solids 13%Cup Weight 130 g. (Sp G. = 0.55)Flow 86Tack 0Size Analysis:On U.S. 20 Mesh = 1%On U.S. 40 Mesh = 19%On U.S. 60 Mesh = 50%On U.S. 80 Mesh = 20%On U.S. 100 Mesh = 6%On U.S. 200 Mesh = 3%Through U.S. 200 Mesh = 1% 100%______________________________________
The base beads are then introduced into a batch rotary drum blender and post sprayed with NEODOL 25-7 at 120° F. and minor ingredients such as coloring agents, perfume, brighteners, etc. to produce a final product as follows:
______________________________________Base Bead (above) 78%Neodol 25-7 (at 120° F.) 19.7%Minors (Color, Perfume, Brightener) 2.3% 100.0%______________________________________
The Neodol is sprayed first, followed by the minors.
Any suitable batch type blender that has provision for spraying liquids, in the form of fine droplets or as a mist, such as a Patterson Kelly twin shell blender, can be used. The post addition spraying operation can also be performed on a continuous basis using suitable mixing apparatus such as the Patterson-Kelly Zig-Zag blender.
The resulting granular detergent has the following properties:
______________________________________FINISHED PRODUCT PROPERTIES______________________________________Cup Weight = 160 g. (Sp G. = 0.68)Flow = 79Tack = 0Size AnalysisOn U.S. 20 Mesh = 1%On U.S. 40 Mesh = 20%On U.S. 60 Mesh = 52%On U.S. 80 Mesh = 20%On U.S. 100 Mesh = 5%On U.S. 200 Mesh = 2%Through U.S. 200 Mesh = 0% 100%______________________________________
The finished product can be packaged on conventional equipment used for packaging granular products.
EXAMPLE 2
An aqueous slurry of the following ingredients is prepared.
______________________________________ Amount, Percent (based on totalIngredients (In order of addition) crutcher mix)______________________________________Hot Water (140° F.) 25.0Sodium Silicate Solids (SiO.sub.2 /Na.sub.2 O = 2.4) 3.5Sodium tripolyphosphate powder (anhydrous) 13.0______________________________________
The aqueous slurry is mixed well in a steam jacketed vessel to hydrate the phosphate ingredient and then heated to 200° F. with steam.
The following ingredients are then added to the aqueous slurry to form a crutcher mix. The temperature is maintained higher than about 180° F. to prevent hydration of subsequently added anhydrous phosphate builder salt.
______________________________________ Amount Percent (based on totalIngredients (In order of addition) crutcher mix)______________________________________Sodium tripolyphosphate (anhydrous) 13.0Water 25.0Sodium tripolyphosphate (anhydrous) 13.0Sodium carbonate 7.5______________________________________
The crutcher mix is supplied to a countercurrent spray drying tower at a temperature of about 170° F. and sprayed at a pressure of 800 psig. The tower conditions include a T 1 (inlet) air temperature of 650° F. and a T 2 (outlet) air temperature of about 235° F.
The spray dried builder beads have a particle size distribution such that 90 percent by weight pass through a 20 mesh screen (U.S. series) and 90 percent by weight are retained on a 200 mesh screen (U.S. series).
The spray dried beads are oversprayed according to the technique used in Example 1 as follows:
______________________________________Overspray Formula Amount Percent______________________________________Spray dried beads 78.0Neodol 25-7 19.5Minor ingredients (optical brighteners, 2.5perfume etc.) 100.0______________________________________
The final product has a cup weight of 180 grams; a flow of 75 percent and a water content of 5 percent by weight.
EXAMPLE 3
The procedures of Example 2 are followed with a crutcher mix (about 50 percent solids) of the following composition:
______________________________________ AmountIngredient Percent______________________________________Sodium tripolyphosphate (hexahydrate) 13.0Sodium tripolyphosphate (anhydrous) 26.0Water 47.0Organic Builder "M" (Monsanto Chemical Co.) 7.5Sodium silicate (solids) 6.5 100.0______________________________________
The spray dried builder beads are oversprayed as follows using the technique of Example 1.
______________________________________Ingredient Amount Percent______________________________________Spray dried builder beads 85.0Nonionic (Neodol 45-11) 12.0Minor Ingredients 3.0 100.0______________________________________
The resulting granular detergent is free flowing, non-tacky and suitable for the home or commercial laundering of clothing.
EXAMPLE 4
Example 1 is repeated using Alfonic 1618-65 nonionic detergent in an amount to provide a final granular detergent having a 30 percent by weight nonionic content.
EXAMPLE 5
Crutcher mixes having the following compositions are prepared according to the procedures of Example 1.
______________________________________ Amount PercentIngredient I II III IV______________________________________Sodium tripolyphosphate 10 12 18 20(hexahydrate)Sodium silicate solids 3 8 6 4(SiO.sub.2 /Na.sub.2 O = 2.4)Sodium tripolyphosphate 30 30 26 28(Anhydrous)Water 57 50 50 48______________________________________
Crutcher mixes I, II, III, and IV are spray dried according to the procedures outlined in Example I. The spray dried beads are oversprayed as follows:
______________________________________ Amount PercentIngredient I II III IV______________________________________Spray dried beads 74.5 80.5 59 83Minor ingredients 0.5 1.5 1 2Neodol 45-11 -- 18.0 -- --Neodol 25-7 25.0 -- 40 --Alfonic 1618-65 -- -- -- 15______________________________________
The resulting granular detergents from runs I, II, III, and IV are free flowing and are very soluble in wash water.
EXAMPLE 6
Spray dried base builder beads produced from crutcher mixes I-IV of example 5 are oversprayed as follows:
______________________________________ Amount (Percent) Crutcher MixIngredient I II III IV______________________________________Spray dried base builder beads 94 79.9 73.5 79.4Neodol 25-7 -- 15 20 12Linear tridecyl benzene sulfonate -- 3 -- 5AROSURF TA100 (sprayed at 180- 6 -- 4 2210° F.)Bluing agent -- 0.1 -- 0.1Optical brightener -- 2 1.5 1Enzymatice compound (dispersed in -- -- 1 0.5a vehicle)______________________________________
The formulations II, III, and IV are suitable for use as laundry detergents. The formulation I is a fabric softener that can be used in a washing machine.
The various post spray drying ingredients of example 6 and those of the other examples can be applied to the base beads either separately or in any suitable combination.
The present process allows the production of free-flowing detergent beads by a method which does not produce pollution (fuming or pluming) and which is economically feasible, with high throughputs, utilizing conventional plant equipment. In addition to making a free-flowing product, the product made is also non-tacky and has improved water solubility relative to prior art detergent powders. Lengthy aging periods are not necessary for the spray dried detergent intermediate beads before they can be treated with the aforementioned overspray ingredients and such aging periods are not needed before filling may be effected. With various other methods for making detergent particles containing nonionics, such aging or curing periods are required, thereby slowing production and causing typing up of storage facilities.
The invention has been described with reference to various specific and preferred embodiments and techniques. However, it should be understood that many variations and modification may be made within the scope of the invention, which is defined by the following claims. | A process for producing free flowing spray dried base builder beads comprising inorganic detergent builders. The builder beads comprise alkali metal phosphate, alkali metal silicate and water. The alkali metal phosphate component includes a hydrated and an anhydrous portion. Relatively large amounts of liquid or liquifiable detergent ingredients such as surface active agents etc. can be applied to the base beads after spray drying, without destroying their free flowing properties. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to installing or running wellbore tubulars such as casing into a wellbore and, more particularly, to a modular handling tool system for holding and lowering the wellbore tubulars into the wellbore.
2. Description of the Background
A string of wellbore tubulars such as casing, depending on the length and type of tubular elements, may weigh hundreds of thousands of pounds. Despite this significant weight, the casing string must be carefully controlled as it is interconnected and lowered into the wellbore. To further complicate this function, wellbore tubulars, such as casing, come in a wide range of diameters and weights. In some cases, the casing may have a relatively thin wall that can be crushed if too much force is applied thereto.
Pneumatic and/or hydraulic casing tools are large gripping devices used for holding and lowering the wellbore tubulars, such as casing, into the previously drilled open hole. These gripping tools may weigh several tons depending on the size and type of slips used therein. The casing tools are typically used in sets comprising one elevator slip assembly and one spider slip assembly. The elevators slip assembly is translationally moveable with respect to the spider slip assembly. The elevator slip assembly is carried by the traveling block. The spider slip assembly may be a flush mount spider used on the drill floor with a rotary drive such as by replacing the master bushing. On the other hand, the spider assembly construction may need to provide a top mount spider that is mounted on the top of the rotary table or drill floor and which may be used with a scaffold or the like. Pneumatic and/or hydraulic control equipment is provided to operate the slips in the elevator slips assembly and in the spider assembly. Numerous pneumatic/hydraulic control lines are used to interconnect and operate the elevator slips assembly and the spider assembly.
To limit any downtime costs due to damage, maintenance, or repairs, it is generally desirable to provide on the rig site location backup or redundant gripping tools for both the elevator slip assembly and also for the type of spider slip assembly used. Thus, at least four tools are generally necessary at the rig site. The rental costs for having four large, rather complicated, tools on location can be substantial although such costs are preferable to the possibility of having one tool damaged without a spare on location. Due to the size and availability, considerable time may be needed to obtain a replacement. To save costs, it would be desirable to reduce such redundancy requirements while still maintaining the system reliability afforded by 100% redundancy.
Various prior art exists that is related to such gripping tools including U.S. Pat. No. 5,909,768, issued Jun. 8, 1999, to Castille et al., which discloses an exemplary apparatus for optimally gripping and releasing a tube. The apparatus has an elevator with a set of slips for optionally gripping and releasing a tube and a spider with a set of slips for optionally gripping and releasing the end of the tube. The elevator and spider slips are in communication with each other by pressurized conduits. The conduits form a pressure circuit to supply pressure to release one set of slips only when the other set of slips is gripping the tube, wherein the apparatus has improved response time. The spider may be hydraulically or pneumatically actuated and the elevator may be pneumatically operated. The spider may be flush mounted.
Other prior art patents may include U.S. Pat. Nos. 3,215,203; 3,708,020; 3,722,603; 4,676,312; 4,842,058, and 5,343,962.
The above referenced prior art does not disclose means for eliminating the need for having two backup tools at the rig site. It would be desirable to provide 100% redundancy for both the spider and the elevator without the need for two backup tools at the rig site. Eliminating even the fourth backup tool would clearly provide a significant 25% economy for both the vendor and the customer. Those skilled in the art have long sought and will appreciate the present invention which addresses these and other problems.
SUMMARY OF THE INVENTION
The present invention was designed to provide more efficient operation to thereby reduce drilling costs due to decreased equipment needs on location or in the provider's warehouse. Manufacturing costs are reduced due to lower cost of building duplicate items rather than multiple items. Therefore, it is an object of the present invention to provide an improved handling system for holding and lowering wellbore tubulars, especially large tubulars such as casing, into the wellbore.
Another object of the present invention is to provide a handling system with 100% redundancy using fewer components.
Yet another object of the present invention is to provide a handling system with few different components.
Yet another object of the present invention is to reduce storage costs.
A feature of the present invention is a plurality of interchangeable gripping sections.
An advantage of the present invention is reduced operational and manufacturing and storage costs.
These and other objects, features, and advantages of the present invention will become apparent from the drawings, the descriptions given herein, and the appended claims. However, the invention is not limited to these objects, features, and advantages.
Therefore, the present invention provides for a handling system for holding and lowering wellbore tubulars for use with a rig having a traveling block and a rig floor. The system comprises at least two gripping modules that may preferably be substantially identical so as to be interchangeable with each other. The at least two gripping modules each have a bowl section and each have a plurality of slips moveable within the bowl section. An elevator adaptor is provided that has at least one connector for coupling to the traveling block. The elevator adapter is attachable with either one of the at least two gripping modules while another of the at least two gripping modules may be attachable to the rig floor. The elevator adaptor preferably defines a bore therein for receiving either one of the at least two gripping modules. The connector for the elevator module may further comprise lifting ears.
A third gripping module may preferably be provided for use in substituting with either of the at least two gripping modules so as to provide system redundancy.
A top mount module may be mountable to the rig floor and is attachable to either of the at least two gripping modules. The top mount body preferably defines a bore therein for receiving either of the at least two gripping modules.
The at least two gripping modules each preferably have a weight supporting shoulder or flange or ring extending radially outwardly for supporting a weight of the wellbore tubulars. The elevator adaptor has an engagement surface for contacting the weight supporting shoulder of either of the at least two gripping modules.
A plurality of slips is preferably longitudinally moveable within each of the at least two gripping modules. A sloping bottom surface within each of the at least two gripping modules is angled with respect to an axis through each of the at least two gripping modules. The sloping surface forms a stop surface for supporting and preventing further longitudinal movement of the plurality of slips toward a gripping position.
Thus, a plurality of rings are preferably within each of the at least two gripping modules. A plurality of slips are provided for each of the at least two gripping modules with each slip having substantially sawtooth set of camming surfaces for camming engagement with the plurality of rings.
A method is for a wellbore tubular handling system for installing wellbore tubulars in a wellbore. The method may preferably comprise providing at least two gripping modules for gripping wellbore tubulars, selecting either of the at least two gripping modules for attachment to the traveling block, and selecting either of the at least two gripping modules for attachment to the rig floor. In one preferred embodiment, the method comprises supplying at least three gripping modules at the rig for gripping wellbore tubulars such that the at least three gripping modules are interchangeable for attachment to either the traveling block or the rig floor. One of the at least three gripping modules provides redundancy for the other two of the at least thee gripping modules. The attachment to the traveling block further comprises providing an elevator module for interconnection between the traveling block and either of the at least two gripping modules.
In one example of operation, the attachment to the rig floor further comprises a top mount module for interconnection between the rig floor and either of the at least two gripping modules. However, the attachment to the rig floor could also comprise a flush mount adaptor ring for interconnection between the rig floor and either of the at least two gripping modules.
In operation, the method may typically comprise providing at least three gripping modules that are substantially identical so as to be interchangeable with each other, supplying the rig with the at least three gripping modules, and also supplying the rig with a tool for attaching any one of the three gripping modules for use with the traveling block.
Thus, one preferred embodiment of the handling system of the present invention comprises a plurality of identical or substantially identical gripping modules such that each of the plurality of gripping modules may be interchangeable with respect to each other. A first of the plurality of substantially identical gripping modules may be mountable to the traveling block. A second of the plurality of substantially identical gripping modules may be mounted such that the traveling block is translationally moveable with respect thereto for cooperation with the first of the plurality of substantially identical gripping modules in holding and lowering the wellbore tubulars. In one embodiment, an elevator/top mount module is provided that may be used either with the elevators or as a top mount module. Thus, the elevator/top mount module may be connectable to either the rig floor or to the traveling block. The elevator/top mount module may receive either the first or the second of the plurality of substantially identical gripping modules
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial elevating view of a drilling rig showing an elevator supported by links from a traveling block and a spider slip assembly supported by the rig floor;
FIG. 2A is a split elevational view, partially in section, of an elevator module supporting an interchangeable gripping module;
FIG. 2B is a top view, partially in section, of the elevator and interchangeable gripping module of FIG. 2A;
FIG. 3 is a split elevational view, in section, of a flush mounted interchangeable gripping module;
FIG. 4 is a split elevational view, in section, of a top mounted interchangeable gripping module; and
FIG. 5 is an elevational view, of a shroud used for guiding the pipe within the interchangeable gripping module of the present invention.
While the present invention will be described in connection with presently preferred embodiments, it will be understood that it is not intended to limit the invention to those embodiments. On the contrary, it is intended to cover all alternatives, modifications, and equivalents included within the spirit of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIG. 1 for general background, there is shown the pertinent portion of a drilling rig 10 which is rigged to run well casing with a prior art elevator slip assembly 12 suspended from links 28 and a traveling block 26 (indicated in dashed lines), having a bottom casing guide 16 . Spider assembly 18 is mounted to rig floor 24 and may or may not have a bottom guide 20 and atop spider guide 22 . Casing joint 34 is being assembled as part of a casing string. Casing joint 34 forms a type of wellbore tubular string which may typically be permanently cemented in place within an open hole wellbore. Casing joint 34 may typically have a collar 36 atone end thereof.
Also shown in FIG. 1, the elevator and spider may be of the type that is air actuated, or partially air actuated, from an air supply 42 which passes through a conduit or hose 38 to elevator 12 and through a conduit or hose 40 to the spider 18 . Interconnected between the elevator 12 and the spider 18 are typically a plurality of conduits or hoses such as hoses or conduits 44 and 46 .
In FIG. 2 A and FIG. 2B, slip-type elevator assembly 50 in accord with the present invention is disclosed. Slip-type elevator assembly 50 includes elevator module 52 and an interchangeable gripping module 54 . In the handling system of the present invention, a plurality of interchangeable gripping modules 54 are used as discussed subsequently. Gripping module 54 is received into bore 56 of elevator module body 59 . Bore 56 is preferably conveniently cylindrical for receiving a cylindrical mating portion of gripping module 54 below shoulder 60 . The outer surface of elevator module body 59 may also preferably be cylindrical for lower manufacturing costs. Load supporting shoulder 60 of gripping module 54 engages load support surface 58 of elevator module 52 for supporting the heavy load of the casing string which may weigh hundreds of thousands of pounds. In a preferred embodiment, shoulder 60 is effectively formed by an increased diameter of gripping module 54 extending upwardly of load supporting shoulder 58 when gripping module 54 is positioned within elevator module 52 as illustrated in FIG. 2 A. Other means besides load supporting shoulder 60 for supporting the weight may be provided such as bars, rings, flanges, and the like which could also be received by mating surfaces on elevator module 52 .
Elevator module 52 may or may not include baseplate 62 which may be made integral to elevator module body 59 . Casing guide 64 may be provided at the bottom of elevator module 52 with a sloped guide surface 66 for guiding the casing into gripping module bore 68 . Elevator module has lifting ears 70 for connecting to links 28 that attach to traveling block 26 . Bolts or other fasteners such as bolt 72 may be used for securing elevator module 52 with respect to gripping module 54 .
Gripping module 54 includes a bowl section 74 with rings or sloping inner surfaces 76 that are used for supporting and urging camming slips 78 into and out of gripping arrangement with the casing, such as casing joint 34 . Bowl section 74 may preferably be longitudinally split or in sections that are constrained or held together in operation by any one of elevator module 52 , the rotary table bore, or top mount body 144 as discussed subsequently. In a presently preferred embodiment, bowl section 74 includes at least three internal load rings 80 , 82 , and 84 which form multiple camming surfaces. Using relatively long slips 78 , very roughly between about one and two feet long, and supported by internal load rings 80 , 82 , and 84 , the handling system of the present invention can handle full rated loads, up to for instance 500 tons, even without crushing thin wall tubulars. In a presently preferred embodiment, lower load ring 84 includes a separate support ring 86 that provides N additional strength by supporting slip 78 at end 88 as shown in the right half of the split view of FIG. 2 A. The left side of FIG. 2A shows slips 78 in a non-gripping or retracted position while the right side of FIG. 2A shows slips 78 in the gripping or extended position.
Slips 78 include a slip shoe 90 which may be mounted by bolts 92 to a sliding support 94 which operates by cams or sloping surfaces of the load rings to move between the retracted (tubular released) and radially inwardly extended (tubular gripped) position as it slides longitudinally generally parallel to axis 96 of gripping module 54 . In the split view of FIG. 2A, movement of sliding support 94 would be between the upward disengaged position (left split view), and the downward engaged position (right split view), respectively. An additional support ring 98 may be provided at the bottom of bowl section 74 to provide additional strength and support.
Gripping module 54 includes a slip operating mechanism which may be hydraulically or pneumatically controlled and is supported within upper housing section 100 . A plurality of cylinders 102 are provided for operating mandrels 104 . Mandrels 104 interconnect with control arms 106 which are pivotally connected to slips 78 . Thus, upward and downward linear motion produced by cylinders 102 is used by camming surfaces, such as camming surfaces 105 on slips 78 and camming surfaces 107 on bowl section 74 to produce radially outwardly and radially inwardly movement of slips 78 for releasing and gripping wellbore tubulars such as casing joint 34 . Preferably, camming surfaces 105 and 107 have a substantially sawtooth profile due to their being several rows to permit spreading the camming pressures over numerous camming surfaces. Thus, each gripping module 54 includes a bowl section 74 , slips 78 , and a slip operating mechanism.
FIG. 3 shows an interchangeable gripping module 54 as may be provided in flush mount spider assembly 110 for use with a rotary table disposed on the rig floor. Gripping module 54 may replace the master bushing in the rotary table on the rig floor. For different types of rotary tables, adapters may be used. Depending on the type of rotary table, a flush mount gripping module 54 may be substantially inserted within the rotary table but upper portions thereof such as upper housing 100 and parts of bowl section 74 may or may not extend above the rig floor. As with slip-type elevator 50 , significant weight must be supported by flush mount assembly 110 . In flush mount assembly 110 using National rotary table 114 , shoulder 60 of gripping module 54 engages upper surface 122 of National rotary table 114 adjacent bore 124 that extends through the rotary table to the wellbore. One or more bolts or other fasteners, such as bolt 126 , may be used to further secure gripping module 54 to the rotary table. For use with other rotary tables such as Continental rotary table 112 , an adapter 128 may preferably be provided. In this configuration, weight from shoulder 60 is transferred to the adapter shoulder 130 which then applies the weight to the rotary table and/or rig floor.
The split view of FIG. 3 also shows slips 78 in a retracted or released position as at 116 and an extended or gripping position as at 118 . It will be noted that the gripping module 54 of FIG. 3 for use as spider assembly 110 is identical or substantially identical to gripping module 54 of FIG. 2 so that gripping modules 54 are conveniently and economically interchangeable with respect to each other.
FIG. 4 shows one possible top mount spider arrangement 140 using the same or another gripping module 54 . Top mount spider arrangement 140 is designed to set on top of the rotary table when the rotary is of a size and/or construction other than those for which gripping module 54 is designed for or may otherwise be adapted to for flush mount purposes. Base member 142 may be secured to the rotary table and/or rig floor. Top mount body 144 preferably defines bore 146 , which as also shown in the above embodiments, receives a preferably cylindrical portion of gripping module 54 . One or more bolts or other fasteners, such as bolt 149 , may be used to secure gripping module 54 within top mount body 144 . Bore 68 extends through gripping module 54 and leads to the wellbore through bore 148 in base member 142 and the hole in the rotary table. Top mount spider arrangement 140 supports the significant weight of the casing string which may be held by slips 78 . Base 142 supports lower ring 98 at surface 152 . Support surface 154 supports shoulder 60 of gripping module 54 . Support arms 150 , which may be of various construction, may be used for positioning, mounting, and/or convenient lifting as desired of top mount spider arrangement 140 . In one embodiment, top mount body 144 could also be used either with the elevators or as a top mount for added redundancy when a top mount spider construction is used.
FIG. 5 shows shroud 160 used in guiding the casing string through gripping module 54 . Shroud 160 and the top 162 and bottom 164 of windows 166 are shown most clearly in FIG. 5 although the respective top 162 and bottom 164 are also indicated in FIG. 2A, FIG. 3, and FIG. 4 . Slips 78 extend through windows 166 in the engaged position for gripping the casing as discussed above. In the disengaged or open position, slips 78 are flush or slightly recessed with respect to shroud 160 .
The interchangeability of gripping modules 54 with each other for use as either an elevator slips or a spider is one of the significant advantages of the present invention. In operation, when the tool handling system of the present invention is sent on a job, three gripping modules 54 will be provided with one elevator module, such as elevator module 52 discussed above. If required, an additional one top mount module is also provided. Since only two gripping modules 54 will actually be used at any one time, the third gripping module 54 will provide 100% redundancy for the spider and the elevator without the need for a fourth tool. This reduces the equipment required by approximately 25% to provide a significant economy for both the vendor and the customer. Moreover, the construction disclosed herein with three internal load rings and long heavy-duty slips allows the handling system of the present invention to handle large loads even with thin wall tubulars without crushing them.
The present invention is effectively a three-in-one handling tool system. The modular tool system can be used as a: 1) flush mount spider; 2) a top mount spider; and/or 3) a slip-type elevator. To briefly summarize, the tool system consist of a split bow module, such as gripping module 54 , that includes the slips and the slip operating mechanism. An elevator module, such as elevator module 52 , is provided. A top mount module, such as top mount body 144 , may also be provided as necessary for providing a top mount spider construction. The gripping or split bowl module 54 will fit into the rotary table or elevator module 52 or top mount body 144 . Thus, each split bowl or gripping module 52 can be utilized for three separate functions. Elevator module 52 mimics the rotary table bore so as to contain the split bowl or gripping module 54 and has integral lifting ears 70 to enable it to function as an elevator. Top mount body 144 is designed to set on top of the rotary table when the rotary is of a size other than the one the gripping module 54 was preferably designed for. Top mount body 144 also mimics the function of the rotary table in constraining the bowl or gripping module 54 and may or may not be made with an integral baseplate, such as baseplate 142 .
The foregoing disclosure and description of the invention is illustrative and explanatory thereof, and it will be appreciated by those skilled in the art, that various changes in the size, shape and materials, the use of mechanical equivalents, as well as in the details of the illustrated construction or combinations of features of the various three-in-one elements may be made without departing from the spirit of the invention. | A wellbore tubular handling system and method is provided for operation in holding and lowering tubulars, such as casing strings, at a rig site. The handling system utilizes a plurality of interchangeable gripping modules for use with both the elevator slips and the spider. Because the gripping modules are completely interchangeable, only one additional gripping module is needed to provide redundancy at the well site to thereby reduce the equipment normally required. An elevator module receives the interchangeable gripping module therein. An interchangeable gripping module may also preferably be flush mounted in many standard rotary table types. Alternatively a top mount spider module is provided to receive a gripping module for other rig floor and/or rotary table constructions. The gripping module has three inner support rings and slips between approximately one and two feet in length to permit load support while protecting any thin walled casing that is used in the casing string. | 4 |
TECHNICAL FIELD
[0001] The invention disclosed herein generally relates to the field of automated access control and authorization. In particular, it relates to a component for evaluating an access request against a policy, such as a policy decision point, and a method for controlling a subject's access to a resource.
BACKGROUND
[0002] On a high level, attribute-based access control (ABAC) may be defined as a method where a subject's requests to perform operations on resources are granted or denied based on assigned attributes of the subject, assigned attributes of the resource, environment conditions, and a set of one or more policies that are specified in terms of those attributes and conditions. Here, attributes are characteristics of the subject, resource, or environment conditions. Attributes contain information given by a name-value pair. A subject is a human user or non-person entity, such as a device that issues access requests to perform operations on resources. Subjects are assigned one or more attributes. A resource (or object) is a system resource for which access is managed by the ABAC system, such as devices, files, records, tables, processes, programs, networks, or domains containing or receiving information. It can be the resource or requested entity, as well as anything upon which an operation may be performed by a subject including data, applications, services, devices, and networks. An operation is the execution of a function at the request of a subject upon a resource. Operations include read, write, edit, delete, copy, execute and modify. Environment conditions describe an operational or situational context in which an access request occurs. Environment conditions are detectable environmental characteristics. Environmental characteristics are generally independent of subject or resource, and may include the current time, day of the week, current stock market index, current temperature, or the current threat level. Finally, a policy is the representation of rules or relationships that makes it possible to determine if a requested access should be allowed, given the values of the attributes of the subject, resource, operation and possibly environment conditions. A policy may be expressed as a logical function, which maps an access request with a set of attribute values (or references to attribute values) to an access decision (or an indication that the request has not returned a decision).
[0003] An ABAC scenario is depicted in FIG. 1 . In step 1 , a user (or subject) 100 requests access to a resource 110 through the intermediary of an ABAC mechanism 120 which selectively protects access to the resource 110 . The ABAC mechanism 120 forms a decision by retrieving, in step 2 a - 2 b - 2 c - 2 d, applicable rules R 1 , R 2 , R 3 from a policy repository 130 , subject attributes (e.g. name, affiliation, clearance) from a subject attribute data source 140 , resource attributes (e.g. type, owner, classification) from a resource attribute data source 150 , and environment conditions expressed as environment attribute values from an environment attribute data source 160 . If the ABAC mechanism 120 is able to determine that the decision is to permit access, it will take appropriate measures to grant the user 100 access to the resource 110 , e.g. by selectively deactivating a hardware or software protection means. Otherwise, access to the resource 110 may be denied.
[0004] There currently exist general-purpose ABAC policy languages that have the richness to express fine-grained conditions and conditions which depend on external data. A first example is the Extensible Access Control Markup Language (XACML) which is the subject of standardization work in a Technical Committee of the Organization for the Advancement of Structured Information Standards (see http://www.oasis-open.org). A policy encoded with XACML consists of declarative (in particular, functional) expressions in attribute values, and the return value (decision) of the policy is one of Permit, Deny, Not Applicable, or Indeterminate. An XACML policy can apply to many different situations, that is, different subjects, resources, operations and environments and may give different results for them. The XACML specification defines how such a request is evaluated against the policy, particularly what policy attributes are to be evaluated or, at least, which values are required to exist for a successful evaluation to result. A key characteristic of this evaluation process is that the request must describe the attempted access to a protected resource fully by containing information sufficient for all necessary attribute values to be retrieved. In practice, it may be that the request is interpreted in multiple stages by different components, so that a PEP (Policy Enforcement Point) issuing the requests provides only some attribute values initially, and a PDP (Policy Decision Point) or other component responsible for the evaluation can dynamically fetch more values from remote sources as they are needed. A second example is the Axiomatics Language For Authorization™, which the applicant provides. XACML-based solutions typically offer “authorization as a service”, wherein a PEP in a target application/system captures access requests in real time and sends them to a PDP for evaluation against a current version of one or more XACML policies. Such externalized authorization approach ensures continuity in that it drastically reduces or eliminates the latency between an update of the policy and actual enforcement of the new rules therein.
[0005] A company may deploy a plurality of applications of ABAC policies in order to separate the plurality of applications. The reasons for separation of a deployment into a plurality of applications may be related to confidentiality of the information in the different applications, e.g. between different units or sites of a company. Further, separation of applications may be related to stability concerns, such that any malfunctions within one application do not affect another application.
[0006] However, a deployment of an ABAC policy consumes information technology (IT) resources of a company. Hence, deployment of a plurality of applications may lead to large overhead costs in IT administration and management. Further, the deployment of a plurality of applications may consume computing resources, mainly memory.
SUMMARY
[0007] It is an object of the invention to enable an improved administration of ABAC policies. It is a further object of the invention to enable isolation of different ABAC policies, while posing insignificant requirements on IT administration resources and computing resources.
[0008] These and other objects of the invention are at least partly met by the invention as defined in the independent claims. Preferred embodiments are set out in the dependent claims.
[0009] According to a first aspect of the invention, there is provided a policy decision point (PDP) for interacting with a computer system comprising a plurality of resources, to which subjects' access is controlled by corresponding policy enforcement points (PEPs), the PDP comprising: a memory configured to store at least two distinct policy packages, each controlling access rights to one or more of the resources in the computer system, and a connection table associating each of said at least two policy packages with one or more end point addresses; a network interface operable to communicate with at least two of the PEPs, wherein the network interface is arranged to obtain one or more access requests from a PEP and return one or more access decisions to a requesting PEP, each access request comprising an end point address associated with the PDP for directing the access request to the PDP; and a processor operable to: analyze an access request obtained by the network interface and determine, based on the end point address receiving the access request, an associated one of said at least two policy packages; and evaluate the access request against the policy package thus determined, thereby obtaining an access decision to be returned to and enforced by the PEP.
[0010] According to a second aspect of the invention, there is provided a computer system, comprising: a plurality of resources; a plurality of PEPs, corresponding to the plurality of resources for controlling subjects' access to the resources; and at least one PDP according to the first aspect of the invention, the PDP being operable to communicate with at least two of the PEPs.
[0011] According to a third aspect of the invention, there is provided a method in a PDP for controlling a subject's access to a resource, the PDP being arranged for interacting with a computer system comprising a plurality of resources, to which subjects' access is controlled by corresponding PEPs, said method comprising: obtaining an access request from a PEP through an end point address of the PDP; analyzing the obtained access request and determining, based on the end point address receiving the access request, an associated one of at least two policy packages stored by the PDP; and evaluating the access request against the policy package thus determined, thereby obtaining an access decision to be returned to and enforced by the PEP.
[0012] According to a fourth aspect of the invention, there is provided a computer program product comprising a computer-readable medium with computer-readable instructions for performing the method of the third aspect.
[0013] Thus, a PDP may comprise at least two policy packages. Further, the PDP may determine a policy package based on an end point address receiving an access request and the access request is then evaluated against this policy package. This implies that a single PDP may be used for handling several policy packages and that it is possible for the PDP to separate between the policy packages so that a request from one application associated with one policy package should not be affected by any malfunctions within another policy package.
[0014] Further, a single PDP may be deployed for handling access requests targeting several applications. This implies that the requirement set on computer resources and hardware capacity may be limited. Also, having a single PDP ensures that deployment of a single server for managing and configuring the ABAC system, including the PDP, is sufficient. This may severely reduce the requirements on IT administration and management resources.
[0015] As used herein, the term “policy package” should be construed as a package that comprises at least one policy set, which each comprise at least one policy, providing rules for mapping an access request to an access decision. The policy may refer to rules within a name space, such that a rule used by a plurality of policies needs only be completely defined and stored once. Within a policy package, references may therefore be made to common rules. The policy package may be administered as a coherent unit, such that an administrator is able to access the policies within the coherent unit when configuring or managing the policy package. The policy package may further comprise references to external rules, not administered within the coherent unit. Two policy packages are considered distinct, when there are no references from the coherent unit of one policy package to rules within the coherent unit of the other policy package. Although not referring to rules within each others' packages, the two policy packages may refer to common external rules. According to one embodiment, the two policy packages are completely separated by not referring to any common rules.
[0016] According to an embodiment, a unique policy package is associated to each end point address. Hence, each request to an end point address will be uniquely evaluated against the associated policy package. This implies that the PDP may isolate handling of the at least two policy packages.
[0017] According to an embodiment, the processor being operable to analyze an access request comprises the processor being operable to extract information indicating an end point that received the access request. Hence, the processor may obtain the end point address of the end point that received the access request in order to determine an associated policy package.
[0018] The information may be extracted from a header of the access request, wherein the header comprises the end point address. This implies that the processor need only read the header of the access request in order to determine an associated policy package. Hence, the processor may quickly determine the associated policy package.
[0019] In an embodiment, the end point address is a uniform resource identifier (URI). URIs are commonly used, e.g. as a uniform resource locator (URL) addressing a page on the World Wide Web and, therefore, almost any computer network will be able to handle a URI. The end point address being a uniform resource identifier may thus facilitate that an access request finds its way to the end point address during transfer of the request over a computer network.
[0020] In an embodiment, the processor is further operable to determine a destination of the access decision based on information in the access request. The access request may carry information to the PDP in order to enable an access decision to be properly returned to the PEP. For instance, the access request may include an address of the PEP that is to receive the access decision. Alternatively, the PDP and the PEP may have an established two-way network connection. In such case, the access request need not include an address. Rather, the processor of the PDP may determine a destination of the access decision based on information of an identity of the PEP sending the access request.
[0021] In evaluating the access request against the policy package, values of such attributes whose values are not explicit in the access request, yet necessary to complete the evaluation of the access request, may be needed. Therefore, the PDP may comprise an attribute connector that may be operable to communicate with a data source, such as a database. The data source may provide information of values of attributes to the attribute connector, and the values may then be used in evaluating the access request. The PDP may comprise a plurality of attribute connectors, which are each associated with a single policy package. This implies that each attribute connector is used by a unique policy package and that the attribute connectors are thereby separated within the PDP. Hence, handling of the policy packages is separated within the PDP, also as far as remote attribute value retrieval is concerned.
[0022] In an embodiment, the PDP further comprises at least one administration end point address for receiving configuration settings of the PDP, wherein the PDP is arranged to allow changes to the policy packages through the at least one administration end point address. By this architecture, configuration of the policy packages is inherently controlled in order to manage access to changing configuration of the policy packages.
[0023] In a further embodiment, an administrator's configuration access to configuration of the PDP is restricted by an administrator account to one policy package associated with one end point address. Hence, an administrator may only access one policy package associated with the administrator account of the administrator, which implies that the policy packages are truly separated. Thus, any mistakes by an administrator in configuring a policy package will not affect the functionality of other policy packages of the PDP.
[0024] In yet a further embodiment, configuration settings controlling attribute connectors may also be received through the administration end point address. The administrator's configuration access to attribute connectors may also be restricted by the administrator account to attribute connectors associated with the accessible policy package. This implies that the administrator may only be allowed to configure one policy package with its associated attribute connectors at a time.
[0025] It is noted that the invention relates to all combinations of features, even if recited in mutually separate claims.
BRIEF DESCRIPTION OF DRAWINGS
[0026] These and other aspects of the present invention will now be described in further detail, with reference to the appended drawings showing embodiment(s) of the invention.
[0027] FIG. 1 is a schematic view illustrating an access scenario in accordance with an ABAC model.
[0028] FIG. 2 is a block diagram showing a computer system equipped with authorization services.
[0029] FIG. 3 is a schematic view illustrating an association of policy packages with end point addresses of a policy decision point.
[0030] FIG. 4 is a flowchart of a method for controlling a subject's access to a resource.
[0031] Unless otherwise stated, the drawings show only such components or features that are necessary to illustrate the example embodiments, while other components may have been intentionally left out in the interest of clarity. Further, like reference numerals refer to like elements on the drawings.
DETAILED DESCRIPTION
[0032] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which currently preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided for thoroughness and completeness, to fully convey the scope of the invention to the skilled person.
[0033] FIG. 2 illustrates an example ABAC implementation and possible flows of information when authorization services 200 process a subject's 100 request to access a resource 110 by using or performing an operation on the resource 110 . The authorization services 200 include a policy enforcement point (PEP) 202 , which selectively permits or prevents the subject's 100 access to the resource 110 , e.g. by selectively activating and deactivating hardware or software protection means, and a policy decision point (PDP) 204 . The access request is to be evaluated against an ABAC policy in a policy repository 130 , which is formed in a memory in the PDP 204 . The policy may be maintained from a policy administration point (PAP) 206 . The PDP 204 may be configured to retrieve necessary information describing the ABAC policy from its internal repository 130 . From a policy information point (PIP) 208 , the PDP 204 may request any such values of policy attributes that are missing from the initial access request but necessary to evaluate the request against the policy. In turn, the PIP 208 may request these values from an attribute repository 140 - 150 storing values of subject, resource, and operation attributes (in this sense, the repository may be seen as an entity combining the functionalities of the data sources 140 and 150 in FIG. 1 and has been labelled accordingly) and/or from an environment conditions repository 160 . The evaluation of the access request may then complete, and a decision may be returned to the subject 100 . If the decision is permissive, the PEP 202 grants access to the resource 110 , as requested.
[0034] A computer system may comprise a plurality of resources 110 to which access is to be controlled. A plurality of PEPs 202 may be arranged to enforce access control to the plurality of resources 110 . The plurality of PEPs 202 may be arranged to communicate with a single PDP 204 in order to obtain access decisions. For brevity, the below description is mainly given in relation to one PEP 202 enforcing access to one resource 110 .
[0035] The subject 100 may be a human user requesting access to a resource 110 . For instance, a person may try to access a file in a computer system, or a physical resource, such as an entrance door with a network-connected, automatically controlled lock. The subject 100 may be identified in the computer system e.g. by means of a user account, which the person is logged on to, or an identifier obtained through an access card applied to a reader connected to the computer system. The subject 100 may alternatively be a non-human entity, such as a computer program being executed in the computer system, which requests access to a resource 110 in the computer system independently of direct user interaction.
[0036] In an example embodiment, the computer system is one or more of the following: a general-purpose file management system; a document management system; a content management system, a financial system; a communications system; an industrial control system; an administrative system; an enterprise system; a simulations system; a computational system; an entertainment system, an educational system; a defence system. In an example embodiment, the resources 110 in the computer system are one or more of the following: devices, files, records, tables, processes, programs, networks, domains containing or receiving information.
[0037] A PEP 202 may be connected to a resource 110 , such that when a subject 100 requests access to the resource 110 , the corresponding PEP 202 is activated.
[0038] The PEP 202 may be implemented in software, hardware, or as any combination of software and hardware. The PEP 202 may, for instance, be implemented as software being executed on a general-purpose computer, as firmware arranged e.g. in an embedded system, or as a specifically designed processing unit, such as an Application-Specific Integrated Circuit (ASIC) or a Field-Programmable Gate Array (FPGA).
[0039] In a particular embodiment, the PEP 202 may be a process that is run on a server in the computer system. When a subject 100 requests access to e.g. a file in the computer system, the PEP 202 may be activated in order to start a process to determine whether access is to be permitted.
[0040] In another embodiment, the PEP 202 may be a process that is run on a processor, which may be co-located with the resource 110 . For instance, if the resource 110 is an entrance, which may be opened only on a permitted access request, the PEP 202 may be run on a processor located at the entrance. Such a localized processor may be connected to the computer system in order to transfer access requests from the PEP 202 to a PDP 204 .
[0041] The PDP 204 may comprise a processor 210 , which is configured to run a process for analyzing and evaluating an acess request. The processor 210 may be any type of processor that is able to execute computer instructions, such as a processor on a general-purpose computer, or a specifically designed processing unit, such as an Application-Specific Integrated Circuit (ASIC) or a Field-Programmable Gate Array (FPGA).
[0042] In an embodiment, the PDP 204 may be implemented in a server in the computer system. In another embodiment, the PDP 204 may be implemented in a local processor with associated memory, which may be co-located with the resource 110 .
[0043] The PDP 204 may further comprise a network interface 212 , which is operable to communicate with the PEP 202 . The PDP 204 may thus receive access requests from the PEP 202 through the network interface 212 and may return access decisions to the PEP 202 through the network interface 212 . The network interface 212 may define one or more end point addresses 302 a - c, forming a contact point for communication between the PDP 204 and the PEP 202 .
[0044] The network interface 212 may be implemented as a process controlling network communication, which is run on the processor 210 . The network interface 212 may alternatively be implemented as hardware for receiving and sending signals in the computer system with corresponding software for controlling such hardware.
[0045] The PDP 204 may further comprise a memory 130 , which stores a policy package against which an access request is to be evaluated. The memory 130 may be implemented as any type of storage for storing information, such as any type of hard disk, a random access memory (RAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory.
[0046] The memory 130 of the PDP 204 may be provided separate from the processor 210 , such that the memory 130 and the processor 210 may e.g. be provided in two different physical computer units. However, the combination of the memory 130 and the processor 210 may still be considered to be included in the PDP 204 .
[0047] In an example embodiment, the ABAC policy or policies which the PDP 204 evaluates is encoded using a markup language. Suitable examples include the following: XML; XACML of the latest standardized version released at the original filing date of the present disclosure, or a future version that is backwards compatible with respect to the applicable standardized XACML version; Axiomatics Language for Authorization™ available from the applicant.
[0048] The processor 210 is connected to the memory 130 such that the processor 210 may access the memory 130 for loading the policy package when an access request is to be evaluated. A policy package may comprise a plurality of policies, which policies may provide rules for handling access requests to different types of resources 110 . The policy package may be administered as a coherent unit, such that an administrator is able to access the policies within the coherent unit when configuring or managing the policy package. Within a policy package, the plurality of policies may refer to common rules, such that a rule needs only to be completely defined and stored once. Also, a policy package may refer to external rules, which may not be administered within the coherent unit.
[0049] When the processor 210 of the PDP 204 receives an access request, the processor 210 accesses the memory 130 in order to fetch the relevant policy. The processor 210 will then evaluate the access request against the policy in order to reach an access decision (or an indication that the request has not returned a decision).
[0050] In order to evaluate the access request, the processor 210 uses attributes assigned to the subject 100 . The access request may comprise values of the attributes. However, some values may not be directly known to the PEP 202 . Hence, the access request may comprise information about the subject 100 that allows the values of the attributes to be determined.
[0051] The PDP 204 may further comprise attribute connectors 214 , which may be arranged to request values of attributes. An attribute connector 214 may be implemented as a process, which may call a PIP 208 . The attribute connector 214 may be set up as a number of rules for creating such calls to the PIP 208 . Based on a call from the attribute connector 214 , the PIP 208 may request the values of attributes from an attribute repository 140 - 150 and/or from an environment conditions repository 160 . A plurality of attribute connectors 214 may be associated with the policy package, e.g. for fetching information of different types of attributes.
[0052] As an example, an access request may comprise an identifier of a subject 100 requesting access to a resource 110 . An attribute connector 214 may send the identifier in a request to a PIP 208 in order to obtain a value of an attribute associated with a property or characteristic of the subject 100 .
[0053] The PIP 208 may then request a value of an attribute from, say, a human resource database within the computer system, in which database the identifier of the subject 100 is associated with the subject's position within the organization. Hence, a value of an organizational position attribute, which is retrieved in the database by using the subject identifier attribute as key, may be returned to the PDP 204 through the PIP 208 and the attribute connector 214 .
[0054] The attribute repositories 140 - 150 and the environment conditions repository 160 may form data sources that could be separately managed. Although the information in the data sources may have a decisive impact on an access decision, its maintenance and updating need not be primarily associated with managing authorizations. Rather, information that is needed to be stored anyway, such as HR, building, computer hardware and other information within an organization, may be stored in a data source and may also be used by the authorization services 200 for obtaining values of attributes.
[0055] The processor 210 of the PDP 204 may be configured to evaluate the access request against the relevant policy, using the determined values of attributes. The processor 210 may thus determine whether access to the resource 110 is to be permitted. If the processor 210 is able to determine that access to the resource 110 is to be permitted, the processor 210 may output an access decision that permits access. Otherwise, the processor 210 may output an access decision that denies access. A policy encoded with XACML may output a value of the access decision as one of Permit, Deny, Not Applicable, or Indeterminate.
[0056] The PDP 204 may return the access decision to the PEP 202 for enforcing the decision. If access is to be permitted, the PEP 202 may e.g. selectively deactivate a hardware or software protection means such that the subject 100 may access the resource 110 . This may imply that the subject 100 is able to perform an operation, such as read, write, edit, delete, copy, execute and modify, on a data object, such as a file, record, table, process, or program. Alternatively, the deactivation of protection means may e.g. imply that a signal is transmitted to a mechanical lock for allowing a door to be opened.
[0057] In the present example, the network interface 212 of the PDP 204 further defines at least one administration end point address 302 d in order to facilitate communication between the PDP 204 and the PAP 206 . The PAP 206 may access a policy package in the memory 130 through the communication via the administration end point address with the network interface 212 in order to allow configuration of the policy package. An administrator's configuration access to configuration of the PDP 204 may be restricted in relation to the administrator account used for accessing the PDP 204 through the PAP 206 .
[0058] The PAP 206 may provide a user interface allowing an administrator to configure and administer the policy package maintained in the PDP 204 . The administrator may log on to the PAP 206 using an administrator account, which may be used as input for restricting access to configuration of the PDP 204 . The PAP 206 may be implemented as pure software, or a combination of software and hardware. The PAP 206 may, for instance, be implemented as a software being executed on a general-purpose computer or as firmware arranged e.g. in an embedded system providing a processor. The PAP 206 may provide a process for enabling an administrator to add or remove policies or change the configuration of a policy package.
[0059] The PAP 206 may also access attribute connectors 214 of the PDP 204 in order to configure the attribute connectors 214 . For instance, the connection to data sources via the PIP 208 may be configured or rules controlling how values of the attributes are to be fetched may be configured, e.g. from what source, using what query language.
[0060] The PDP 204 may store a plurality of distinct policy packages, at least two, in the memory 130 . Two policy packages are considered distinct, when there are no references from the coherent unit of one policy package to rules within the coherent unit of the other policy package. These distinct policy packages may be handled separately within the PDP 204 . This implies that the PDP 204 may support PEPs 202 of completely different applications within the computer system, without the operation of one policy package affecting other policy packages.
[0061] A computer system may be used by a number of different applications and users, which have different requirements. For instance, the computer system may be used in support or running of an industrial process of a company. The computer system may also be used for managing a finance system of the company. It may therefore be important that any malfunctions or problems within one application do not affect another application in the computer system. For instance, the control of accesses within the running of an industrial process should not be affected by any disruptions within the finance system.
[0062] Thanks to the PDP's 204 storing a plurality of distinct policy packages and separately handling these policy packages, a plurality of applications within a computer system may be managed by the same PDP 204 without a risk of problems within one application using one policy package propagating to other applications using other policy packages. Hence, there is no need for deploying a plurality of authorization services 200 with respective PDPs in order to separate the applications from each other. Rather, the handling of the applications may be performed separately within a PDP 204 of the authorization services 200 .
[0063] As further illustrated in FIG. 3 , the first network interface 212 of the PDP 204 may be configured with a plurality of end point addresses 302 a - c. The memory 130 of the PDP 204 may further comprise a connection table 304 , which associates each of the plurality of policy packages with one or more of the end point addresses 302 a - c. The connection table 304 may associate a unique policy package to each end point address 302 a - c.
[0064] The end point address 302 a - c may be a uniform resource identifier (URI), such as a uniform resource locator (URL). The end point address 302 a - c being an URL facilitates that an access request finds its way to the end point address 302 a - c during transfer of the request in the computer system.
[0065] A PEP 202 may be set up to send access requests to one specific end point address 302 a, 302 b or 302 c of the PDP 204 . The PEP 202 will thus always communicate with the PDP 204 through the set-up end point address. Upon set-up of the authorization services 200 , two-way communication between the PDP 204 and the PEP 202 may be established, such that the PDP 204 will also know a destination address of messages to be sent to the PEP 202 .
[0066] addresses 302 a - c, the corresponding policy package associated with the end point address 302 a - c may be determined from the connection table 304 . Hence, the correct policy package related to the requesting PEP 204 will always be used.
[0067] The PDP 204 may also comprise a plurality of sets of attribute connectors 214 . Each set of attribute connectors 214 may be associated to a unique policy package, such that the sets of attribute connectors 214 are separated from each other. Hence, the fetching of values of attributes via the PIP 208 will be separately controlled by a unique set of attribute connectors 214 for each policy package. This further ensures separation of the handling of access requests for different applications.
[0068] The administration of the policy packages and the sets of attribute connectors 214 may also be separated. The PDP 204 may only allow access to a single policy package and its associated set of attribute connectors 214 at a time. An administrator account of the PAP 206 may be associated with a single policy package, such that another administrator account needs to be used if another policy package is to be administered. Hence, administration of different policy packages may be separated to different users and associated with their respective administrator accounts.
[0069] Alternatively, separate instances of the PAP 206 may be arranged to communicate with different administration end point addresses, and each policy package may be associated with an administration end point address for restricting configuration access to the policy package through the administration end point address on which communication to the PDP 204 is established. As a further alternative, only a single policy package may be able to be administered during a single session of communication between the PAP 206 and the PDP 204 . Hence, if two policy packages are to be administered, two separate sessions of the PAP 206 contacting the PDP 204 needs to be used.
[0070] Referring now to FIG. 4 , a method 400 of handling an access request will be described. A PEP 202 identifies that a subject 100 desires access to a resource 110 . The PEP 202 then generates and sends an access request to the specific end point address 302 a - c, which is pre-defined in the set-up of the PEP 202 . The PDP 204 receives the access request at the end point address 302 a - c, step 402 . The access request is transferred to the processor 210 of the PDP 204 .
[0071] The processor 210 analyzes the access request, step 404 . First, the processor 210 determines an end point address 302 a - c that received the access request. This may be determined by means of the transfer of the access request from the end point address 302 a - c to the processor 210 signalling which end point address 302 a - c received the access request. Alternatively, the processor 210 may extract information from the access request indicating the end point address 302 a - c. For instance, the end point address 302 a - c may be extracted from a header of the access request.
[0072] The processor 210 makes a look-up in the connection table 304 in order to find the policy package that is associated with the end point address 302 a - c that received the access request, step 406 . The processor 210 then establishes access to the correct policy package.
[0073] The processor 210 determines which policy in the policy package that the access request should be evaluated against. This may depend on the resource 110 to which access is requested. The processor 210 then determines which attributes that will be used in the evaluation of the policy. If values of any of these attributes are not available, an attribute connector 214 is triggered to request the values of the attributes, step 408 . The attribute connector 214 sends a corresponding request to the PIP 208 , which forwards a request to obtain the values of the attributes to the corresponding data source(s), such as the attribute repositories 140 - 150 or the environment conditions repository 160 . The thus obtained values of the attributes are returned to the processor 210 .
[0074] Once the access request, the policy and the values of the necessary attributes are available to the processor 210 , the processor 210 may evaluate the access request against the policy, step 410 . The evaluation of the access request may even be commenced before all values of necessary attributes are available, such that the processor 210 may perform the evaluation step 410 at least partly in parallel with values of attributes being obtained in step 408 . The policy may be a logical function, which maps a set of values of attributes to an access decision. Hence, providing the access request and the set of values of attributes as input, the evaluation will return an access decision, step 412 , which may be permission or denial of access to the resource 110 .
[0075] The processor determines a destination address of the access decision. This may be performed by extracting the destination address from the access request or by a two-way communication with the requesting PEP 202 being established, such that the destination address is known to the processor 210 . The processor 210 then transmits the access decision to the PEP 202 via the first network interface 212 , step 414 .
[0076] The PEP 202 receives the access decision and enforces the decision, step 416 . If the access decision is to permit access to the resource 110 , the PEP 202 may deactivate a hardware or software protection means so as to allow the subject 100 access to the resource 110 .
[0077] A computer program product may comprise computer-readable instructions for controlling the processor 210 to perform the method of controlling a subject's access to a resource as described above. The computer program product may be distributed on computer readable media, which may comprise computer storage media (or non-transitory media) and communication media (or transitory media). As is well known to a person skilled in the art, the term computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by a computer. Further, it is well known to the skilled person that communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media.
[0078] Even though the present disclosure describes and depicts specific example embodiments, the invention is not restricted to these specific examples. Modifications and variations to the above example embodiments can be made without departing from the scope of the invention, which is defined by the accompanying claims only.
[0079] In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs appearing in the claims are not to be understood as limiting their scope. | The present invention relates to a policy decision point for interacting with a computer system comprising a plurality of resources, to which subjects' access is controlled by corresponding policy enforcement points. The PDP comprises: a memory storing at least two policy packages, each controlling access rights to resources, and a connection table associating each policy package with an end point address; a network interface operable to communicate with the PEPs, wherein the network interface obtains access requests from a PEP and returns access decisions to the PEP, each access request comprising an end point address for directing the access request to the PDP; and a processor operable to: analyze an access request and determine, based on the end point address receiving the access request, an associated policy package; and evaluate the access request against the policy package thus determined. | 7 |
BACKGROUND OF THE INVENTION
A flashlight normally must be held in the hand of the user or his helper in order to effectively direct the light to the work area. It is known in the art to provide flashlights with ring members at one end that they may be used to hang the light from a nail or suspended from one's belt. Flashlight cases also include clip members for this purpose. Some larger portable battery-operated lights have flat bases which facilitate placing the light in a stationary position on a flat surface. However, little attention has been paid in this art to the problem of effectively supporting a tubular flashlight in one or more positions so that the light therefrom can be directed to a work area at different angles.
SUMMARY OF THE INVENTION
In accordance with this invention the aforementioned problems are overcome by providing a support member for a flashlight that includes a base upon which the flashlight can be supported at a plurality of angles upwardly and a plurality of angles directing the light downwardly. The device includes a base member adapted to rest upon a flat surface and the base member includes a plurality of transverse ridges or notches against which the rear edge or the front edge of the flashlight may be engaged. A U-shaped or bifurcated support member is pivotally attached to or hingeably engaged by one end of the supporting base. Preferably this U-shaped member is made of wire rod and has two arms that extend in substantially parallel spaced relationship from the ends of a cross member that forms the hinge. An elastic member such as a spring, rubberband or ribbon of plastic is attached between the two arms of the support for the purpose of engaging the underside of the flashlight case. Not only can the angle of the light be changed by placing its base end or lens end against different notches or ridges on the base of the device but the attitude or height of the other end of the flashlight can be varied by moving the elastic member or spring upwardly or downwardly on the bifurcated arms of the hinged support. Thus, the flashlight can be supported with the light directed at a number of angles upwardly or a number of differnt angles downwardly.
The hinged U-shaped support member can have its cross member at the hinged end encompassed by a rolled end edge of the base when it is fabricated from sheet metal or the cross member can engage an end corner in the base defined by a bottom and an end wall. Also, the bottom of the base member may have a transverse slot which engages the cross member of the support to provide a hinged relationship. Means may also be included to hold the bifurcated support member at selected angles upwardly from one end of the base. The distance between the bifurcated arms of the supporting base may be substantially the same as or slightly less than the diameter of the flashlight case so as to engage the sides of the case and further grip the flashlight. This allows the flashlight to be set upon the base and held in a vertical position.
DESCRIPTION OF THE DRAWINGS
Illustrative embodiments of the invention are shown in the drawings wherein:
FIG. 1 is a perspective view of one form of the flashlight support of this invention, in this instance formed from sheet metal;
FIG. 2 is a cross-sectional view taken along lines 2--2 of FIG. 1 and showing a flashlight supported by the device;
FIG. 3 is a perspective view of another form of the device, in this case fabricated from molded plastic with the flashlight supported thereby shown in broken lines;
FIG. 4 is a plan view of the bifurcated hinged supporting member with the transverse elastic support shown in two positions along the bifurcated legs;
FIG. 5 is a fragmentary view of the hinge construction like that of FIG. 2 to show a modification wherein the end edge of the rolled edge of the sheet metal base bears one or more notches which hold the upright bifurcated supporting member in at least two angular positions;
FIG. 6 is a fragmentary cross-sectional view of another form of the device shown supporting a flashlight in a vertical position;
FIG. 7 is a fragmentary end view of the embodiment of FIG. 6;
FIG. 8 is a fragmentary perspective view of one end of the device showing a modified form of detent to prevent the end of the flashlight from sliding on the base;
FIG. 9 is a perspective view of one modification of the invention;
FIG. 10 is an exploded view of the hinge portion of the embodiment of FIG. 9;
FIG. 11 is a fragmentary side view of the hinge portion of FIG. 9;
FIG. 12 is a fragmentary plan view of a modified base for use with the embodiment of FIGS. 9 and 10; and
FIG. 13 is a fragmentary view of still another embodiment of the hinge that can be used with this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2 the flashlight holder 10 is illustrated by a base member 12 defining a flat upper surface 14 and having downwardly directed side flanges 16 and 18 (FIG. 2) and a single end flange 20 all being of the same width so that the supporting base 12 can be placed on a planar surface to support a flashlight. The flanges 16, 18 and 20 are formed in the sheet metal base by cutting out the corners 22 and bending the flanges downwardly along the corner bends 24, for example.
The opposite end flange 26 has been formed into a tubular roll to engage over the transverse portion or cross member 28 of the bifurcated support 30. The support 30 has two parallel legs or arms 32 and 34 which are substantially the same length and slightly shorter than the length of the base 12. This arrangement provides a hinge at the rolled flange 26 which allows the bifurcated support 30 to lie flat on the base 12 as shown in FIG. 1 or assume various angular positions, one of which is illustrated in FIG. 2.
The base 12 includes a series of transverse spaced ridges 36 which have been formed or cut from the sheet metal so that they extend upwardly and provide a raised edge 38 against which the bottom corner 40 of the flashlight 42 can engage, as illustrated in FIG. 2. The ridges 36 need only be of a height and length sufficient to catch and hold the flashlight case corner 40 to keep it from sliding.
An elastic member illustrated by the coil spring 44 is tied across the legs 32 and 34 to engage under the case of the flashlight as shown in FIG. 2. In this instance the last coils 45 are bent out at each end to receive the rod members 32 and 34. Instead of a spring 44 an elastic band can be looped across the rod members 32 and 34 or a plastic ribbon can be used.
It is apparent from FIGS. 1 and 2 that the flashlight 42 can have its bottom corner 40 at the cap end engaging upon any one of the three ridges 36 shown or that the light can be reversed and the corner 46 can also engage these ridges, if one desires to reverse the position of the flashlight in the holder. Not only may the angle of the support 30 be changed but the longitudinal position of the elastic member 44 can be changed along the legs 32 and 34. This is shown in FIG. 4 wherein the spring 44 is shown in a full line position 44 and a broken line position at 44a.
In FIG. 3 another embodiment of the invention is shown employing a modified form of base 12a, in this case molded of plastic. The modified base 12a has the end sidewalls 50 and 52 and the longer sidewalls 54 and 56 which extend from and above the planar inner supporting surface 58. A series of three transverse and longitudinally spaced bar members 60 are attached to or formed as an integral part of the flat inner base 58.
Any length of spacing can be used for these bar members and any number of bar members may be employed. In this embodiment the hinged supporting member 30 used is the same as that shown in FIGS. 1 and 2. However, no special hinge means is employed in this embodiment and the transverse cross member 28, here hidden behind the end wall 50, merely engages in this corner defined by the inner surface of the upright wall 50 and the flat inner base portion 58.
The bifurcated support member 30 shown in FIG. 3 may hinge downwardly and be contained within the walls of the case when not in use. The flashlight 42 is shown in broken lines in FIG. 3 with its light or lens end 66 directed downwardly and the base end 64 in a raised position. The flashlight 42 can also engage the end wall 52 and still be supported by the member 30 and its transverse spring 44.
When the flashlight holder illustrated in FIGS. 1, 2 and 3 is used to support a flashlight in a vertical position the base end 64 would engage the flat surface 58 of the base 12 immediately between the rolled hinge end 26 or the end wall 50 and the innermost ridge 36 or bar 60 so that it would be upon a flat surface. The flashlight 42 can also be shifted from side to side between the walls 54 and 56 to further change the direction of lighting where the device is used in closed-in areas as may be found around machinery or furnaces and the like.
In FIGS. 6 and 7 the vertical placement of a flashlight 42 at any position along the base is facilitated by providing a modified plastic base 12b wherein the top surface 58 is formed with a series of spaced or shaped notches 66, formed with an arcuate bottom 68 and a vertical end wall 70 as shown in FIG. 8. Such an indentation may be molded into the plastic body of the surface 58 so as to fit the corners 40 and 46 of the flashlight.
FIGS. 6 and 7 illustrate the manner in which a flashlight 42 can be supported in a vertical position wherein its base end 64 rests upon the flat surface 58 of the base 12b, the lens end projects vertically. The bifurcated support member 30 has its legs 32 and 34 on each side of the flashlight case and in a slight bearing relationship thereagainst. This can be accomplished by having the bifurcated legs 32 and 34 sprung or biased slightly inwardly and also by means of the spring 44 which can urge the bifurcated legs toward each other and against the flashlight case. In this position the spring 44 may or may not be slid to a position where it is in contact with the case. The spring 44 engages the legs 32 and 34 in a sliding relationship by means of the circular ends 45 which are bent around the legs 32 and 34.
The base 12b (FIG. 6) has the elongated transverse notch or groove 72 in the surface 58 between the end wall 50 and the second inner wall 74 which hingeably supports the bifurcated support 30 by receiving the cross member 28. Further adjustment is provided by the corner 76 wherein the cross member 28 can also fit.
In FIG. 5 it is shown that the edge 80 of the rolled hinge portion 26 can have one or more slots 82 which engage the leg 32 so that it will drop into the slots and assume different angular positions. The inwardly biased condition of the legs 32 and 34 facilitates this spring and detent action. One or both ends of the rolled hinge portion 26 can have such edge notches 82. The legs 32 and 34 may be sand blasted to increase their functional engagement with the spring edges 45 and the case of the flashlight 42.
The legs 32 and 34 can also be formed with outwardly curved off-sets that fit the contour of the sides of the case 42 with or without the biasing band 44. Alternately the legs 32 and 34 can converge toward each other at the cross-member 28, thus shortening the length of the cross-member. These embodiments could however limit the extent of vertical adjustments of the end of the flashlight supported thereby. However, this would allow the base member 12 to be fabricated in reduced widths. The length of the base member 12 is about that of a standard two-cell battery case or longer so as to accommodate three- and four-cell cases, if desired.
FIGS. 9, 10 and 11 illustrate a further embodiment wherein the modified base 12d is also formed of stiff wire and has the spaced legs 80 with the end eyelets 82 which encircle the cross member 28 at each end of the compression spring 44c. The spring 44c biases the legs outwardly so that the eyelets 82 engage the inside surfaces of the legs 32 and 34 of the bifurcated support member 30 in a sufficient frictional relationship so that this member can be placed at selected angles and support the flashlight 42 thereon. The cross bar 84 completes the structure of this base 12d.
The spring 44b replaces the notches 66 and bars 60 to perform their functions and also to be adapted to slide to selected positions along the legs 80. The springs 44 can be the same or different spiral configuration and the springs 44 and 44b can be rubber-coated. These parts are shown in disassembled relationship in FIG. 10.
In FIG. 12 the further modified wire base 12c includes the inwardly bent tabs 86 which are adapted to engage within the open end loops of the spring 44c to form another combination of support, replacing the loops 82 shown in FIG. 9.
The spring 44b has been omitted from the arms 80 of the base 12c for simplicity. The arms 80 would be spread to accomplish the engagement of the tabs 86 and facilitate assembly by hand.
In FIG. 13 the combination of the base 12d of FIG. 9 and a modified bifurcated support member 30a is shown wherein the cross-member 28 has been modified by peening at the points 88 just inside the eyelets 82 to form a hinge and keep the legs 80 in position. As shown in FIG. 11 both the spring 44c and the peened points 88 can be omitted if the eyelets are formed tighter about the cross-member 28. The cross-member 84 can be used as the only or additional support for the corners 40 and 46 of the flashlight 42. | An adjustable flashlight holder is disclosed having a base member with a plurality of transverse spaced ridge elements or shaped depressions along its top surface and a bifurcated support hinged to one end to engage the flashlight at various angles. In one embodiment the arms of the support are biased toward each other sufficiently to engage the flashlight case diametrically and include an elastic member or spring upon which the case of the flashlight may rest at an angle. In another embodiment the hinge has one or more lock positions to hold the support at selected angles and folds down on top of or within the base member when not in use. The flashlight can be supported in a variety of convenient positions to facilitate use by a worker. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] Pursuant to 35 USC § 119(e), this application claims priority to U.S. Provisional Application Ser. No. 60/641,218, filed Dec. 31, 2004, the contents of which are incorporated herein by reference.
BACKGROUND
[0002] Cancer treatment can be approached by several modes of therapy, including surgery, radiation, chemotherapy, or a combination of any of these treatments. Among them, chemotherapy is indispensable for inoperable or metastatic forms of cancer.
[0003] The microtubule system of eukaryotic cells is an important target for developing anti-cancer agents. More specifically, tubulin polymerization/depolymerization is a popular target for new chemotherapeutic agents. A variety of clinically used compounds (e.g., paclitaxel, epothilone A, vinblastine, combretastatin A-4, dolastatin 10, and colchicine) target tubulin polymerization/depolymerization and disrupt cellular microtubule structures, resulting in mitotic arrest and inhibition of the growth of new vascular epithelial cells. See, e.g., Jordan et al. (1998) Med. Res. Rev. 18: 259-296. Thus, those compounds may have the ability to inhibit excessive angiogenesis, which occurs in diseases such as cancer (both solid and hematologic tumors), cardiovascular diseases (e.g., atherosclerosis), chronic inflammation (e.g., rheutatoid arthritis or Crohn's disease), diabetes (e.g., diabetic retinopathy), macular degeneration, psoriasis, endometriosis, and ocular disorders (e.g., corneal or retinal neovascularization). See, e.g., Griggs et al. (2002) Am. J. Pathol. 160(3): 1097-103.
[0004] Take combretastatin A-4 (CA-4) for example. CA-4, isolated by Pettit and co-workers in 1982 ( Can. J. Chem. 60: 1374-1376), is one of the most potent anti-mitotic agents derived from the stem wood of the South African tree Combretum caffrum . This agent shows strong cytotoxicity against a wide variety of human cancer cells, including multi-drug resistant cancer cells. See, e.g., Pettit et al. (1995) J. Med. Chem. 38: 1666-1672; Lin et al. (1989) Biochemistry 28: 6984-6991; and Lin et al. (1988) Mol. Pharmacol. 34: 200-208. CA-4, structurally similar to colchicines, possesses a higher affinity for the colchicine binding site on tubulin than colchicine itself. Pettit et al. (1989) Experientia 45: 209-211. It also has been shown to possess anti-angiogenesis activity. See Pinney et al. WO 01/68654A2. The low water-solubility of CA-4 limits its efficacy in vivo. See, e.g., Chaplin et al. (1999) Anticancer Research 19: 189-195; and Grosios et al. (1999) Br. J. Cancer 81: 1318-1327.
[0005] Identification of compounds that also target the microtubule system (e.g., tubulin polymerization/depolymerization) can lead to new therapeutics useful in treating or preventing cancer or symptoms associated with cancer.
SUMMARY
[0006] This invention is based on a surprising discovery that a group of fused bicyclic heteroaryl compounds effectively inhibit the growth of certain cancer cells.
[0007] In one aspect, this invention features fused bicyclic heteroaryl compounds.
[0008] One subset of the fused bicyclic heteroaryl compounds have the following formula:
in which each ---- is a single bond or a double bond; A is C(═O), CRR′, O, NR, S, SO, or SO 2 ; D is aryl or hetereoaryl; R 1 is selected from H, alkyl, aryl, alkoxy, hydroxy, halo, amino, or alkylamino; each of Q, U, V, and Y, independently, is CR or N; X is N, CR, or NR′; Z is C; and each of T and W is C or N, at least one of T and W being C; provided that when T is C and W is N, the bond between T and W is a single bond, the bond between T and Z is a double bond, the bond between Y and Z is a single band, the bond between X and Y is a double bond, the bond between W and X is a single bond, and X is N or CR; when T is N and W is C, the bond between T and W is a single bond, the bond between T and Z is a single bond, the bond between Y and Z is a double band, the bond between X and Y is a single bond, the bond between W and X is a double bond, and X is N or CR; and when T is C and W is C, the bond between T and W is a double bond, the bond between T and Z is a single bond, the bond between Y and Z is a double band, the bond between X and Y is a single bond, the bond between W and X is a single bond and X is NR and Y is N, or X is NR, Y is CR, and at least one of Q, U and V is N. Each of R and R′, independently, is H, alkyl, alkenyl, alkynyl, aryl, heteroaryl, cyclyl, heterocyclyl, SO 3 R a , SO 2 R a , SO 2 NR a R b , COR a , COOR a , or CONR a R b ; each R a and R b , independently, is H, alkyl, alkenyl, alkynyl, aryl, heteroaryl, cyclyl, or heterocyclyl.
[0009] Referring to this formula, the compounds may have the following feature: each of T and X is N, W is C, each of Q, U, and V is CH, and Y is CR; each of T and W is C, X is NH, Y is N, and each of Q, U, and V is CH; each of T and W is C, each of Q and U is CH, V is N, X is NH, and Y is CR; T is C, W is N, each of Q, U, V, and X is CH, and Y is CR; T is N, W is C, each of Q, U, V, and X is CH, and Y is CR; T is C, W is N, each of Q, U, and V, is CH, X is N, and Y is CR; each of T and W is C, each of Q, U, and V is CH, X is O, and Y is N; each of T and W is C, Q is CH, or each of U and V is N, X is NH, and Y is CR; or T is C, each of W, V, and X is N, each of Q and U is CH, and Y is CR. Further, the compounds may have one or more of the following features: D is substituted phenyl, e.g., 3,4,5-trimethoxyphenyl; A is C(O); and A is CH 2 , NH, O, S, or SO 2 .
[0010] Another subset of the fused bicyclic heteroaryl compounds have the following formula:
in which each ---- is a single bond or a double bond; A is C(═O), CRR′, O, NR, S, SO, or SO 2 ; D is aryl or hetereoaryl; R 1 is selected from alkyl, aryl, alkoxy, hydroxy, halo, amino, or alkylamino; each of Q, U, or V, independently, is CR or N; X is O or S; Y is CR″ or N; each of T, W, and Z is C; the bond between T and W is a double bond; the bond between T and Z is a single bond; the bond between Y and Z is a double band; the bond between X and Y is a single bond; and the bond between W and X is a single bond. Each of R and R′, independently, is H, alkyl, alkenyl, alkynyl, aryl, heteroaryl, cyclyl, heterocyclyl, SO 3 R a , SO 2 R a , SO 2 NR a R b , COR a , COOR a , or CONR a R b , and R″ is H, alkyl, alkenyl, alkynyl, heteroaryl, cyclyl, heterocyclyl, SO 3 R a , SO 2 R a , SO 2 NR a R b , COR a , COOR a , or CONR a R b ; each R a and R b , independently, is H, alkyl, alkenyl, alkynyl, aryl, heteroaryl, cyclyl, or heterocyclyl.
[0011] Referring to the above formula, the compounds may have one or more of the features: each of Q, U, and V is CH, and Y is CR; D is substituted phenyl, e.g., 3,4,5-trimethoxyphenyl; A is C(O); and Y is CH, CNH 2 , CCH 3 , or CCH 2 CH 3 .
[0012] The term “alkyl” herein refers to a straight or branched hydrocarbon, containing 1-10 carbon atoms. Examples of alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, and t-butyl. The term “alkenyl” refers to a straight or branched hydrocarbon, containing 1-10 carbon atoms and one or more double bonds. The term “alkynyl” refers to a straight or branched hydrocarbon, containing 1-10 carbon atoms and one or more triple bonds. The term “alkoxy” refers to an —O-alkyl. The term “amino” refers to a nitrogen radical which is bonded to two hydrogen, or one hydrogen and one alkyl groups, or two alkyl groups.
[0013] The term “aryl” refers to a 6-carbon monocyclic, 10-carbon bicyclic, 14-carbon tricyclic aromatic ring system wherein each ring may have 1 to 4 substituents. Examples of aryl groups include, but are not limited to, phenyl, naphthyl, and anthracenyl. The term “aryloxy” refers to an —O-aryl. The term “aralkyl” refers to an alkyl group substituted with an aryl group.
[0014] The term “cyclyl” refers to a saturated and partially unsaturated cyclic hydrocarbon group having 3 to 12 carbons. Examples of cyclyl groups include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclopentenyl, cyclohexyl, cyclohexenyl, cycloheptyl, and cyclooctyl.
[0015] The term “heteroaryl” refers to an aromatic 5-8 membered monocyclic, 8-12 membered bicyclic, or 11-14 membered tricyclic ring system having one or more heteroatoms (such as O, N, or S). Examples of heteroaryl groups include pyridyl, furyl, imidazolyl, benzimidazolyl, pyrimidinyl, thienyl, quinolinyl, indolyl, and thiazolyl. The term “heteroaralkyl” refers to an alkyl group substituted with a heteroaryl group.
[0016] The term “heterocyclyl” refers to a nonaromatic 5-8 membered monocyclic, 8-12 membered bicyclic, or 11-14 membered tricyclic ring system having one or more heteroatoms (such as O, N, or S). Examples of heterocyclyl groups include, but are not limited to, piperazinyl, pyrrolidinyl, dioxanyl, morpholinyl, and tetrahydrofuranyl.
[0017] Alkyl, alkenyl, alkynyl, cyclyl, heterocyclyl, aryl, heteroaryl, and alkoxy mentioned herein include both substituted and unsubstituted moieties. Examples of substituents include, but are not limited to, halo, hydroxyl, amino, cyano, nitro, mercapto, alkoxycarbonyl, amido, carboxy, alkanesulfonyl, alkylcarbonyl, carbamido, carbamyl, carboxyl, thioureido, thiocyanato, sulfonamido, alkyl, alkenyl, alkynyl, alkyloxy, aryl, heteroaryl, cyclyl, heterocyclyl, in which alkyl, alkenyl, alkynyl, alkyloxy, aryl, heteroaryl cyclyl, and heterocyclyl are optionally further substituted.
[0018] Shown below are some examples of the bicyclic heteroaryl compounds of this invention:
[0019] Some other examples of the compounds of this invention are shown below:
[0020] The bicyclic heteroaryl compounds described above inhibit cancer cell growth. Thus, in another aspect, this invention also features a method for treating cancer. The method includes administering to a subject in need thereof an effective amount of one of the above-mentioned compounds.
[0021] In still another aspect, this invention features a method for inhibiting tubulin polymerization, or treating an angiogenesis-related disorder. The method includes administering to a subject in need thereof an effective amount of one or more of the above-mentioned compounds.
[0022] Also within the scope of this invention is a composition containing one or more of the above-described compounds for use in treating cancer or an angiogenesis-related disorder, as well as the use of such a composition for the manufacture of a medicament for treating cancer or an angiogenesis-related disorder.
[0023] The details of many embodiments of the invention are set forth in the description below. Other features, objects, and advantages of the invention will be apparent from the description and the claims.
DETAILED DESCRIPTION
[0024] The fused dicyclic heteroaryl compounds described above can be prepared by methods well known in the art. For example, synthesis of indazole, imidazo[1,2-a]pyridine, 1H-pyrrolo[2,3-b]pyridine, indolizine, pyrazolo[1,5-a]pyridine, benzo[d]isoxazole, and 7H-pyrrolo[2,3-d]pyrimidine has been described in the literature. See, e.g., Chemistry of Heterocyclic Compounds, Vol. 22, Edited by Richard H. Wiley, Published by Interscience Publishers, New York, 1967. One skilled in the art can modify these methods and make the fused dicyclic heteroaryl compounds of this invention. Shown in Schemes 1-4 are synthetic routes for compounds 1, 2, 3, and 7, respectively.
[0025] To synthesize the compounds of this invention, suitable synthetic chemistry transformations and protecting group methodologies (protection and deprotection) may be used. These transformations and methodologies are known in the art and include, for example, those described in R. Larock, Comprehensive Organic Transformations , VCH Publishers (1989); T. W. Greene and P. G. M. Wuts, Protective Groups in Organic Synthesis, 3 rd Ed., John Wiley and Sons (1999); L. Fieser and M. Fieser, Fieser and Fieser's Reagents for Organic Synthesis , John Wiley and Sons (1994); and L. Paquette, ed., Encyclopedia of Reagents for Organic Synthesis , John Wiley and Sons (1995) and subsequent editions thereof.
[0026] A synthesized fused bicyclic heterocyclic compound can be further purified by flash column chromatography, high performance liquid chromatography, or crystallization.
[0027] Also within the scope of this invention is a pharmaceutical composition that contains an effective amount of at least one fused bicyclic heterocyclic compound of this invention and a pharmaceutically acceptable carrier. Further, this invention covers a method for inhibiting tubulin polymerization or treating cancer or an angiogenesis-related disorder. The method includes administering to a subject an effective amount of a fused bicyclic heterocyclic compounds described in the “Summary” section.
[0028] As used herein, the term “treating” refers to administering a fused bicyclic heteroaryl compound to a subject that has a disorder, e.g., cancer or an angiogenesis-related disorder, or has a symptom of such a disorder, or has a predisposition toward such a disorder, with the purpose to cure, heal, alleviate, relieve, alter, remedy, ameliorate, improve, or affect the disorder, the symptoms of the disorder, or the predisposition toward the disorder. The term “an effective amount” refers to the amount of the active agent that is required to confer the intended therapeutic effect in the subject. Effective amounts may vary, as recognized by those skilled in the art, depending on route of administration, excipient usage, and the possibility of co-usage with other agents.
[0029] As used herein, the term “cancer” refers to cells having the capacity for autonomous growth, i.e., an abnormal state or condition characterized by rapidly proliferating cell growth. In addition, cancer can be a drug resistance phenotype wherein cancer cells express P-glycoprotein, multidrug resistance-associated proteins, lung cancer resistance-associated proteins, breast cancer resistance proteins, or other proteins associated with resistance to anti-cancer drugs. Examples of cancers include, but are not limited to, carcinoma and sarcoma such as leukemia, sarcomas, osteosarcoma, lymphomas, melanoma, ovarian cancer, skin cancer, testicular cancer, gastric cancer, pancreatic cancer, renal cancer, breast cancer, prostate cancer, colorectal cancer, cancer of head and neck, brain cancer, esophageal cancer, bladder cancer, adrenal cortical cancer, lung cancer, bronchus cancer, endometrial cancer, nasopharyngeal cancer, cervical or hepatic cancer, or cancer of unknown primary site.
[0030] The term “angiogenesis” refers to the growth of new blood vessels—an important natural process occurring in the body. In many serious diseases states, the body loses control over angiogenesis. Angiogenesis-dependent diseases result when new blood vessels grow excessively. Examples of angiogenesis-related disorders include cardiovascular diseases (e.g., atherosclerosis), chronic inflammation (e.g., rheutatoid arthritis or Crohn's disease), diabetes (e.g., diabetic retinopathy), macular degeneration, psoriasis, endometriosis, and ocular disorders (e.g., corneal or retinal neovascularization).
[0031] To practice the method of the present invention, the above-described pharmaceutical composition can be administered orally, parenterally, by inhalation spray, topically, rectally, nasally, buccally, vaginally or via an implanted reservoir. The term “parenteral” as used herein includes subcutaneous, intracutaneous, intravenous, intramuscular, intraarticular, intraarterial, intrasynovial, intrasternal, intrathecal, intralesional and intracranial injection or infusion techniques.
[0032] A sterile injectable composition, e.g., a sterile injectable aqueous or oleaginous suspension, can be formulated according to techniques known in the art using suitable dispersing or wetting agents (such as Tween 80) and suspending agents. The sterile injectable preparation can also be a sterile injectable solution or suspension in a non-toxic parenterally acceptable diluent or solvent, for example, as a solution in 1,3-butanediol. Among the acceptable vehicles and solvents that can be employed are mannitol, water, Ringer's solution and isotonic sodium chloride solution. In addition, sterile, fixed oils are conventionally employed as a solvent or suspending medium (e.g., synthetic mono- or diglycerides). Fatty acids, such as oleic acid and its glyceride derivatives are useful in the preparation of injectables, as are natural pharmaceutically-acceptable oils, such as olive oil or castor oil, especially in their polyoxyethylated versions. These oil solutions or suspensions can also contain a long-chain alcohol diluent or dispersant, or carboxymethyl cellulose or similar dispersing agents. Other commonly used surfactants such as Tweens or Spans or other similar emulsifying agents or bioavailability enhancers which are commonly used in the manufacture of pharmaceutically acceptable solid, liquid, or other dosage forms can also be used for the purposes of formulation.
[0033] A composition for oral administration can be any orally acceptable dosage form including, but not limited to, capsules, tablets, emulsions and aqueous suspensions, dispersions and solutions. In the case of tablets for oral use, carriers which are commonly used include lactose and corn starch. Lubricating agents, such as magnesium stearate, are also typically added. For oral administration in a capsule form, useful diluents include lactose and dried corn starch. When aqueous suspensions or emulsions are administered orally, the active ingredient can be suspended or dissolved in an oily phase combined with emulsifying or suspending agents. If desired, certain sweetening, flavoring, or coloring agents can be added. A nasal aerosol or inhalation composition can be prepared according to techniques well-known in the art of pharmaceutical formulation and can be prepared as solutions in saline, employing benzyl alcohol or other suitable preservatives, absorption promoters to enhance bioavailability, fluorocarbons, and/or other solubilizing or dispersing agents known in the art. A fused bicyclic heterocyclic compound-containing composition can also be administered in the form of suppositories for rectal administration.
[0034] The carrier in the pharmaceutical composition must be “acceptable” in the sense of being compatible with the active ingredient of the formulation (and preferably, capable of stabilizing it) and not deleterious to the subject to be treated. For example, solubilizing agents such as cyclodextrins, which form specific, more soluble complexes with the fused bicyclic heterocyclic compounds, or one or more solubilizing agents, can be utilized as pharmaceutical excipients for delivery of the fused bicyclic heterocyclic compounds. Examples of other carriers include colloidal silicon dioxide, magnesium stearate, cellulose, sodium lauryl sulfate, and D&C Yellow # 10.
[0035] Suitable in vitro assays can be used to preliminarily evaluate the efficacy of one or more of the fused bicyclic heterocyclic compounds in inhibiting growth of cancer cell lines. The compounds can further be examined for its efficacy in treating cancer by in vivo assays. For example, the compounds can be administered to an animal (e.g., a mouse model) having cancer and its therapeutic effects are then assessed. Based on the results, an appropriate dosage range and administration route can also be determined.
[0036] The fused bicyclic heterocyclic compounds described above can be screened for the efficacy in inhibiting tubulin polymerization and inhibiting angiogenesis by the methods described in the specific examples below.
[0037] Without further elaboration, it is believed that the above description has adequately enabled the present invention. The following specific embodiments are, therefore, to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way whatsoever. All of the publications cited herein are hereby incorporated by reference in their entirety.
EXAMPLES
Example 1
Synthesis of (7-methoxy-imidazo[1,2-a]pyridin-3-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 1)
[0038] 7-Methoxyimidazo[1,2-a]pyridine was prepared according to the method described in Loeber, S., et al., Bioorg Med Chem Lett 1999, 9 (1), 97-102.
[0039] 7-Methoxyimidazo[1,2-a]pyridine (621 mg, 4.2 mmol) was mixed with POCl 3 (16.8 mmol) in dimethylformamide (4 mL). The reaction mixture was heated at 90° C. for 24 h and then cooled to room temperature. After the solvent was removed in vacuo, an oil was obtained. The oil was purified on a silica gel column eluting with EtOAc/Hexane (1:1) to afford 7-methoxyimidazo[1,2-a]pyridine-3-carbaldehyde (508 mg, 69%).
[0040] To a dry flask equipped with a condenser, an addition funnel, and a magnetic stirrer were added magnesium turnings (2.5 mmol), 0.5 mL of anhydrous tetrahydrofuran (THF), and a small piece of iodine. To this was added via the addition funnel approximately ⅓ of 3,4,5-trimethoxybromobenzene (2.5 mmol) in 1.3 mL of THF. When the solution became colorless (heating may be needed), the remaining 3,4,5-trimethoxybromobenzene solution was added dropwise to the solution under mild refluxing. The reaction mixture was stirred for 1 h at room temperature and then slowly added to 7-methoxyimidazo[1,2-a]pyridine-3-carbaldehyde (0.094 g, 0.53 mmol) in THF (3 mL) at 0° C. After the addition, the solution was allowed to stir at room temperature for another 20 min. Then, a saturated NH 4 Cl solution (5 mL) was slowly added at 0° C., and the mixture was stirred for 10 min. The aqueous layer was separated and extracted with Et 2 O (3×10 mL). The combined organic layers were washed with brine, dried over MgSO 4 , and filtered. The filtrate was concentrated in vacuo and the residue was purified by column chromatography to provide benzhydrol (0.119 g).
[0041] MnO 2 (0.444 g, 5.1 mmol) was added to a solution of benzhydrol (0.115 g, 0.33 mmol) in 5 mL anhydrous CH 2 Cl 2 at 0° C. with stirring. After the addition, the mixture was stirred at room temperature for 8 h. The mixture was diluted with anhydrous ether (50 mL) and filtered through a pad of Celite. The filtrate was concentrated in vacuo and the residue was purified by flash chromatography to give compound 1 (0.087 g, 76%).
[0042] 1 H NMR (300 MHz, CDCl 3 ) δ 3.92 (s, 9H, —OC H 3 ), 3.94 (s, 3H, —OC H 3 ), 6.83 (dd, 1H, J=7.5, 1.5 Hz), 7.11 (s, 2H), 7.12 (d, 1H, J=1.5 Hz), 8.16 (s, 1H), 9.49 (d, J=1H, 7.5 Hz)
Example 2
Synthesis of (7-methoxy-2-methyl-imidazo[1,2-a]pyridin-3-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 2)
[0043] A mixture of 4-methoxy-2-aminopyridine (1.07 g, 8.6 mmol) and ethyl 2-chloroacetoacetate (5.4 g) in EtOH (50 mL) was refluxed for 24 h. The reaction mixture was then concentrated to half its volume, extracted with CH 2 Cl 2 , washed with brine and then water, and dried over anhydrous MgSO 4 . The solvent was removed in vacuo and the residue was purified on a silica gel column eluting with EtOAc and then MeOH/CH 2 Cl 2 (1:9) to give ethyl 7-methoxy-2-methylimidazo[1,2-a]pyridine-3-carboxylate (2.71 g, 90%).
[0044] A mixture of the resulting product (0.340 g, 1.04 mmol) in THF (15 mL) was stirred for 10 min at 0° C. under N 2 . Lithium aluminum hydride (LAH) was added and the mixture stirred overnight at room temperature under N 2 . An aqueous NH 4 Cl solution (5 mL) was then added. The mixture was concentrated to half its volume and extracted with EtOAc. The combined organic layers were washed with brine and water, dried over anhydrous MgSO 4 , and evaporated to give a residue. MnO 2 (0.783 g, 9 mmol) was added to the residue in anhydrous CH 2 Cl 2 (15 mL) at 0° C. with stirring. After the addition, the mixture was stirred at room temperature for 8 h, diluted with anhydrous ether (50 mL) and filtered through a pad of Celite. The filtrate was concentrated in vacuo and the residue was purified by flash chromatography to give 7-methoxy-2-methylimidazo[1,2-a]pyridine-3-carbaldehyde (0.070 g, 53%).
[0045] The resulting product was then reacted with 3,4,5-trimethoxybromobenzene and then oxidized by MnO 2 in a manner similar to that described in Example 1 to afford compound 2 at a yield of 55%.
[0046] 1 H NMR (300 MHz, CDCl 3 ) δ 2.22 (s, 3H, —C H 3 ), 3.89 (s, 6H, —OC H 3 ), 3.92 (s, 3H, —OC H 3 ), 3.93 (s, 3H, —OC H 3 ), 6.71 (dd, 1H, J=7.8, 2.4 Hz), 6.92 (s, 3H), 9.24 (d, 1H, J=7.8 Hz).
Example 3
Synthesis of (6-methoxy-3a,7a-dihydro-1H-indazol-3-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 3)
[0047] A mixture of 6-methoxy-1H-indazole-3-carboxylic acid (0.200 g, 1.04 mmol) in THF (15 mL) was stirred for 10 min at 0° C. under N 2 . LAH was added and the mixture was stirred overnight at room temperature under N 2 . Then, an aqueous NH 4 Cl solution (5 mL) was added and the reaction mixture was concentrated to half its volume and extracted with EtOAc. The organic layer was washed with brine and water, dried over anhydrous MgSO 4 , and the solvent removed in vacuo to give a residue. MnO 2 (0.680 g, 7.8 mmol) was added to the residue in anhydrous CH 2 Cl 2 (15 mL) at 0° C. with stirring. After the addition, the mixture was stirred at room temperature for 8 h. The mixture was diluted with anhydrous ether (50 mL) and filtered through a pad of Celite. The filtrate was concentrated in vacuo and the residue was purified by flash chromatography to give 6-methoxy-1H-indazole-3-carbaldehyde (0.100 g, 56%).
[0048] The resulting product was coupled with 3,4,5-trimethoxybromobenzene and subsequently oxidized by MnO 2 in a manner similar to that described in Example 1 to afford compound 3 at a yield of 54%.
[0049] 1 H NMR (300 MHz, CDCl 3 ) δ 3.89 (s, 3H, —OC H 3 ), 3.93 (s, 6H, —OC H 3 ), 3.94 (s, 3H, —OC H 3 ), 6.90 (d, 1H, J=2.1 Hz), 7.01 (dd, 1H, J=9, 2.1 Hz), 7.665 (s, 2H), 8.27 (d, 1H, J=9 Hz), 10.44 (s, 1H).
Example 4
Synthesis of (6-methoxy-indolizin-1-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 4)
[0050] Potassium tert-butoxide (5.4 g, 48 mmol) was added to 3-methyl-pyridin-3-ol (5 g, 45.87 mmol) in THF (200 mL) at 0° C. The mixture was stirred at room temperature for 30 min. MeI (3.2 mL, 48 mmol) was added dropwise at 0° C. and stirring was continued at room temperature for 8 h. Water was added and the mixture was evaporated to half its volume and extracted with EtOAc. The organic layer was washed with brine and water, dried over anhydrous MgSO 4 , and filtered. The filtrate was concentrated in vacuo, and the residue was purified by flash chromatography to give 5-methoxy-2-methyl-pyridine (4.8 g, 85%).
[0051] n-BuLi in hexane (1.6 M, 7.6 mL, 11.9 mmol) was added dropwise to a solution of diisopropylamine (1.089 g, 10.9 mmol) in THF (25 mL) at −60 to −70° C. under N 2 . The mixture was stirred for 10 min. A solution of 5-methoxy-2-methyl-pyridine (1.274 g, 10.35 mmol) in THF (5 mL) was added dropwise to the above mixture. Stirring was continued for another 10 min and 3,4,5-trimethoxybenzonitrile (1.88 g, 9.74 mmol) in THF (5 mL) was added at −70° C. The mixture was stirred at −78° C. for 1 h and then allowed to warm to room temperature. Stirring was continued for another 2 h and the reaction mixture was poured into an ice-cold aqueous NH 4 Cl solution. The organic layer was separated and the aqueous phase was extracted with ether. The combined organic layers were extracted with a dilute HCl solution. The aqueous layer was washed with ether, neutralized with 10% aqueous NaOH, and extracted with ether. The organic layer was washed with water and dried. The residue was purified by chromatography eluting with CH 2 Cl 2 to give 2-(5-methoxypyridin-2-yl)-1-(3,4,5-trimethoxyphenyl)ethanone (2.31 g, 75.0%).
[0052] A mixture of the resulting pyridine derivative (0.200 g, 0.631 mmol), chloroacetaldehyde (0.099 g, 1.3 mmol), and NaHCO 3 (0.212 g, 2.6 mmol) in acetone (5 mL) was refluxed for 20 h. The precipitate was removed by filtration. The filtrate was concentrated to give a residue, which was purified on a silica gel column eluting with CH 2 Cl 2 to afford compound 4 (0.184 g, 95%).
[0053] 1 H NMR (300 MHz, CDCl 3 ) δ 3.86 (s, 3H, —OC H 3 ), 3.91 (s, 6H, —OC H 3 ), 3.93 (s, 3H, —OC H 3 ), 7.00 (dd, 1H, J=9.6, 1.5 Hz), 7.08 (d, 1H, J=3 Hz), 7.10 (s, 2H), 7.62 (d, 1H, J=1.5 Hz), 8.37 (d, J=1H, 9.6 Hz).
Example 5
Synthesis of (6-methoxy-2-methyl-indolizin-1-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 5)
[0054] A mixture of 2-(5-methoxypyridin-2-yl)-1-(3,4,5-trimethoxyphenyl)ethanone (0.200 g, 0.631 mmol), 1-bromo-2-propanone (0.171 g, 1.3 mmol), and NaHCO 3 (0.212 g, 2.6 mmol) in acetone (5 mL) was refluxed for 20 h. The precipitate was removed by filtration. The filtrate was concentrated to give a residue, which was purified on a silica gel column eluting with CH 2 Cl 2 to afford compound 5 (0.213 g, 95%).
[0055] 1 H NMR (300 MHz, CDCl 3 ) δ2.29 (s, 3H, —C H 3 ), 3.81 (s, 3H, —OC H 3 ), 3.85 (s, 6H, —OC H 3 ), 3.92 (s, 3H, —OC H 3 ), 6.74 (dd, 1H, J=9.6, 2.1 Hz), 6.97 (s, 2H), 7.08 (s, 1H), 7.40 (d, 1H, J=9.6 Hz), 7.50 (d, 1H, J=2.1 Hz).
Example 6
Synthesis of (2-ethyl-6-methoxy-indolizin-1-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 6)
[0056] A mixture of A mixture of 2-(5-methoxypyridin-2-yl)-1-(3,4,5-trimethoxyphenyl)ethanone (0.200 g, 0.631 mmol), 1-bromo-2-butanone (0.190 g, 1.3 mmol), and NaHCO 3 (0.212 g, 2.6 mmol) in acetone (5 mL) was heated under reflux for 20 h. The precipitate was removed by filtration. The filtrate was concentrated to give a residue, which was purified on a silica gel column eluting with CH 2 Cl 2 to afford compound 6 (0.213 g, 92%).
[0057] 1 H NMR (300 MHz, CDCl 3 ) δ 1.23 (t, 3H, —CH 2 C H 3 , J=7.5 Hz), 2.79 (q, 2H, —C H 2 CH 3 , J=7.5 Hz), 3.81 (s, 3H, —OC H 3 ), 3.84 (s, 6H, —OC H 3 ), 3.92 (s, 3H, —OC H 3 ), 6.71 (dd, 1H, J=9.9, 2.1 Hz), 6.97 (s, 2H), 7.13 (s, 1H), 7.31 (d, 1H, J=9.9 Hz), 7.52 (d, 1H, J=2.1 Hz).
Example 7
Synthesis of (7-methoxy-2-methyl-indolizin-3-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 7)
[0058] Methylzinc chloride in THF (2 M, 10.489 mL, 21 mmol) was added to a solution of 2-chloro-4-methoxypyridine (0.500 g, 3.48 mmol) and Pd(PPh 3 ) 4 (0.161 g, 0.14 mmol) in THF (10 mL). The mixture was refluxed for 40 h and then poured into an aqueous solution (10 mL) containing ethylenediaminetetraacetic acid (1.5 g). The resulting mixture was neutralized with K 2 CO 3 and extracted with Et 2 O. The organic layer was concentrated to give a residue, which was purified on a silica gel column eluting with MeOH:EtOAc (1:10) to give 4-methoxy-2-methylpyridine (0.213 g, 50.0%).
[0059] 4-Methoxy-2-methylpyridine (0.123 g, 1 mmol) and bromoacetone (0.16 mL, 1 mmol) were heated at 95° C. under N 2 for 2 h. 1,8-Diazabicyclo-[5.4.0]-undec-7-ene (0.34 mL, 2.2 mmol) in benzene (10 mL) was added. The mixture was then refluxed under N 2 for 1 h, poured into ice water, and then extracted with EtOAc. The combined organic layers were washed with water and dried. After the solvent was removed in vacuo, the residue was purified on a silica gel column eluting with EtOAc:Hexane (1:9) and EtOAc to give 7-methoxy-2-methylindolizine (0.050 g, 31%).
[0060] A mixture of the indolizine 7-methoxy-2-methylindolizine (0.040 g, 0.25 mmol, 1 eq.), substituted benzoyl chloride (2.0 eq.), and Et 3 N (5.0 eq.) was heated at 90° C. (bath temperature) for 2-8 h. The reaction mixture was cooled to room temperature, and EtOAc was added. The organic layer was separated and washed with dilute HCl and water and dried. After the solvent was removed, the residue was purified on a silica gel column eluting with EtOAc:hexane (1:9) to give compound 7 (0.065 g, 74%).
[0061] 1 H NMR (300 MHz, CDCl 3 ) δ 1.97 (s, 3H, —C H 3 ), 3.91 (s, 3H, —OC H 3 ), 3.88 (s, 9H, —OC H 3 ), 6.15 (s, 1H), 6.54 (dd, 1H, J=7.8, 2.7 Hz), 6.69 (d, 1H, J=2.7 Hz), 6.85 (s, 2H), 9.62 (s, 1H)
Example 8
Synthesis of (6-methyl-1H-pyrrolo[2,3-b]pyridin-3-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 8)
[0062] 6-Chloro-1-(phenylsulfonyl)-1H-pyrrolo[2,3-b]pyridine was prepared by the method described in Samuel C. et al., Heterocycles, 1990, 30 (1), 627-633.
[0063] A solution of methylzinc chloride in THF (2 M) (9 mL, 12 mmol) was added to 6-chloro-1-(phenylsulfonyl)-1H-pyrrolo[2,3-b]pyridine (0.600 g, 2.05 mmol) and Pd(PPh 3 ) 4 (0.095 g, 0.08 mmol) in THF (30 mL). The mixture was refluxed for 40 h, cooled to 0° C., quenched with water and extracted with Et 2 O. The organic layer was concentrated and the residue was purified over a silica gel column eluting with EtOAc/hexane (1:5) to give N-protected 6-methyl-7-azaindole (0.495 g, 88%).
[0064] A solution of 50% NaOH (0.573 g) was added to N-protected 6-methyl-7-azaindole (0.390 g, 1.43 mmol) in Ethanol (10 mL). After refluxed for 8 h, the mixture was concentrated and was extracted with CHCl 3 . The organic layer was washed with water and dried. The solvent was evaporated in vacuo and the residue was purified on a silica gel column eluting with EtOAc/hexane (1:3) to give 6-methyl-1H-pyrrolo[2,3-b]pyridine (0.148 g, 78%).
[0065] Ethylmagnesium bromide (3.0 M solution in diethyl ether, 0.43 mL) was added to a mixture of 6-methyl-1H-pyrrolo[2,3-b]pyridine (0.127 g, 0.969 mmol) and anhydrous zinc chloride (0.263 g, 1.94 mmol) in dry CH 2 Cl 2 (20 mL) over 10 min at room temperature. The suspension was stirred for 1 h and then a solution of 3,4,5-trimethoxybenzoyl chloride (0.335 g, 1.45 mmol) in dry CH 2 Cl 2 (10 mL) was added dropwise over 5 min. After 1 h, aluminum chloride (0.129 g, 0.969 mmol) was added. The resulting thick mixture was vigorously stirred for 5 h. The reaction was quenched with water (10 mL) and extracted with CH 2 Cl 2 (20 mL). The organic layer was dried over anhydrous MgSO 4 and concentrated to give a brown oil, which was further purified on a silica gel column (MeOH:CH 2 Cl 2 =1:25) to give compound 8 (0.150 g, 48%) as a white solid.
[0066] 1 H NMR (300 MHz, CDCl 3 ) δ 2.76 (s, 3H, —C H 3 ), 3.92 (s, 6H, —OC H 3 ), 3.96 (s, 3H, —OC H 3 ), 7.17 (s, 2H), 7.21(d, 1H, J=8.1 Hz), 7.90 (s, 1H), 8.59 (d, 1H, J=8.1 Hz), 13.29 (s, 1H)
Example 9
Synthesis of (6-methoxy-1H-pyrrolo[2,3-b]pyridin-3-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 9)
[0067] 7-Azaindole N-oxide was prepared by the method described in Minakata et al., Synthesis, 1992, 7, 661-663.
[0068] A mixture of 7-azaindole N-oxide (5.55 g, 8.6 mmol) in Ac 2 O (30 mL) was refluxed for 12 h. The reaction mixture was concentrated to half its volume, extracted with CH 2 Cl 2 , washed with water, dried over anhydrous MgSO 4 , and evaporated to give a residue, which was purified on a column of silica gel eluting with EtOAc/hexane (1:6) to give 1-acetyl-1H-pyrrolo[2,3-b]pyridin-6-yl acetate (4.55 g, 70%).
[0069] A mixture of 1-acetyl-1H-pyrrolo[2,3-b]pyridin-6-yl acetate (0.635 g, 2.9 mmol) and K 2 CO 3 (1.6 g, 12 mmol) in MeOH/H 2 O (20 mL/20 mL) was stirred at room temperature for 12 h. The reaction mixture was concentrated to half its volume and extracted with CHCl 3 . The organic layer was dried over anhydrous MgSO 4 and evaporated to give a residue, which was further purified on a silica gel column to give 1H-pyrrolo[2,3-b]pyridin-6-ol (0.233 g, 60%).
[0070] A mixture of 1H-pyrrolo[2,3-b]pyridin-6-ol (0.200 g, 1.49 mmol) and K 2 CO 3 (1 g, 7.45 mmol) in acetone (30 mL) was stirred under N 2 at room temperature for 1 h. MeI (0.166 g, 1.192 mmol) was added. The reaction mixture was stirred under N 2 at 50° C. for 12 h and then filtered. The filtrate was concentrated to half its volume, diluted with water, and extracted with CH 2 Cl 2 . The organic layer was dried over anhydrous MgSO 4 , and evaporated to give a residue, which was purified on a column of silica gel eluting with EtOAc/hexane (1:4) to give 6-methoxy-1H-pyrrolo[2,3-b]pyridine (159 mg, 89%).
[0071] Ethylmagnesium bromide (3.0 M solution in diethyl ether, 0.33 mL) was added to a mixture of 6-methoxy-1H-pyrrolo[2,3-b]pyridine (0.108 g, 0.73 mmol) and anhydrous zinc chloride (0.201 g, 1.46 mmol) in dry CH 2 Cl 2 (20 mL) over 10 min at room temperature. The suspension was stirred for 1 h and 3,4,5-trimethoxybenzoyl chloride (0.252 g, 1.09 mmol) in dry CH 2 Cl 2 (10 mL) was then added dropwise over 5 min. After the reaction mixture was stirred for 1 h, aluminum chloride (0.097 g, 0.73 mmol) was added. The resulting thick mixture was vigorously stirred for 5 h. The reaction was quenched with water (10 mL) and extracted with CH 2 Cl 2 (20 mL). The combined organic layers were dried over anhydrous MgSO 4 and evaporated to give a brown oil, which was purified on a silica gel column eluting with EtOAc/hexane (1:1) to compound 9 (0.189 g, 76%).
[0072] 1 H NMR (300 MHz, CDCl 3 ) δ 3.91 (s, 6H, —OC H 3 ), 3.94 (s, 3H, —OC H 3 ), 3.99 (s, 3H, —OC H 3 ), 6.78(d, 1H, J=8.7 Hz), 7.12 (s, 2H), 7.64(d, 1H, J=3 Hz), 8.49(d, 1H, J=8.7 Hz), 9.09 (s, 1H)
Example 10
Synthesis of (6-ethoxy-1H-pyrrolo[2,3-b]pyridin-3-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 10)
[0073] Compound 10 was prepared by the same method described in Example 9 except EtI, instead of MeI, was used.
[0074] 1 H NMR (300 MHz, CDCl 3 ): δ 1.45(t, 1H, —OCH 2 C H 3 , J=6.9 Hz), 3.91 (s, 3H, —OC H 3 ), 3.93 (s, 3H, —OC H 3 ), 3.94 (s, 3H, —OC H 3 ), 4.39(q, 2H, —OC H 2 CH 3 , J=6.9 Hz), 6.76(d, 1H, J=9 Hz), 7.12 (s, 2H), 7.62(d, 1H, J=3 Hz), 8.48(d, 1H, J=9 Hz), 8.93 (s, 1H)
Example 11
Synthesis of (6-methoxy-3a,7a-dihydro-benzofuran-3-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 11)
[0075] A mixture of (6-methoxy-benzofuran-3-yl)-acetic acid (2 g, 9.7 mmol) and H 2 SO 4 (0.3 mL) in methanol (40 mL) was refluxed for 8 h and then concentrated. An aqueous NaHCO 3 solution was added, followed by extraction with CH 2 Cl 2 . The combined organic layers were dried over anhydrous MgSO 4 and evaporated to give a brown oil, which was purified on a silica gel column eluting with EtOAc/hexane (1:10) to give methyl 2-(6-methoxybenzofuran-3-yl)acetate (2.1 g, 98%)
[0076] A mixture of methyl 2-(6-methoxybenzofuran-3-yl)acetate (0.500 g, 2.27 mmol) and SeO 2 (0.303 g, 2.73 mmol) in 1,4-dioxane (10 mL) was refluxed for 2 days and then filtered. The filtrate was concentrated in vacuo and the residue was purified on a silica gel column to give methyl 2-(6-methoxybenzofuran-3-yl)-2-oxoacetate (0.452 g, 85%)
[0077] LAH (0.093 g, 2.39 mmol) was added to a mixture of methyl 2-(6-methoxybenzofuran-3-yl)-2-oxoacetate (0.280 g, 1.196 mmol) in THF (10 mL) at 0° C. under N 2 , and the mixture was stirred overnight at room temperature under N 2 . An aqueous NH 4 Cl solution (5 mL) was added, and the reaction mixture was concentrated to half its volume and extracted with EtOAc. The organic layer was washed with brine and water, dried over anhydrous MgSO 4 , and evaporated to give 1-(6-methoxy-benzofuran-3-yl)-ethane-1,2-diol.
[0078] NaIO 4 (0.204 g, 1.12 mmol) was added to 1-(6-methoxy-benzofuran-3-yl)-ethane-1,2-diol (0.180 g, 1.196 mmol) in THF (50 mL) and water (1 mL) with stirring. The mixture was stirred overnight at room temperature under N 2 . Water (10 mL) was added, and the mixture was concentrated to half its volume and extracted with EtOAc. The organic layer was washed with brine and water, dried over anhyd. MgSO 4 , and evaporated to give a residue, which was purified on a silica gel column eluting with EtOAc/hexane (1:10) to give 6-methoxybenzofuran-3-carbaldehyde (0.110 g, 73%).
[0079] To a dry flask equipped with a condenser, an addition funnel, and a magnetic stirrer were added magnesium turnings (2.5 mmol), THF (0.5 mL), and a small piece of iodine. To this was added via the addition funnel approximately ⅓ of 3,4,5-trimethoxybromobenzene (2.5 mmol) in 1.3 mL of THF. When the solution became colorless (heating may be needed), the remaining 3,4,5-trimethoxybromobenzene solution was added dropwise to the solution under mild refluxing. Stirring was then continued for 1 h at room temperature. The resulting solution was then slowly added to 6-methoxybenzofuran-3-carbaldehyde (0.100 g, 0.176 mmol) in anhydrous THF (5 mL) at 0° C. After the addition, the solution was allowed to stir at room temperature for another 20 min. Then, a saturated NH 4 Cl solution (5 mL) was slowly added at 0° C., and the mixture was stirred for 10 min. The aqueous layer was separated and extracted with Et 2 O (3×10 mL). The combined organic layers were washed with brine, dried over MgSO 4 , and filtered. The filtrate was concentrated in vacuo and the residue was purified by column chromatography to provide benzhydrol (0.097 g, 50%).
[0080] MnO 2 (0.193 g, 1.88 mmol) was added to a solution of benzhydrol (0.050 g, 0.145 mmol) in 5 mL anhydrous CH 2 Cl 2 at 0° C. with stirring. After the addition, the mixture was stirred at room temperature for 8 h. The mixture was diluted with anhydrous ether (50 mL) and filtered through a pad of Celite. The filtrate was concentrated in vacuo and the residue was purified by flash chromatography to give compound 11 (0.043 g, 87%)
[0081] 1 H NMR (300 MHz, CDCl 3 ) δ 3.89 (s, 3H, —OC H 3 ), 3.92 (s, 6H, —OC H 3 ), 3.95 (s, 3H, —OC H 3 ), 7.03(dd, 1H, J=8.4, 2.1 Hz), 7.08(d, 1H, J=2.1 Hz), 7.16 (s, 2H), 8.03(s, 1H), 8.05 (d, 1H, J=9.3 Hz).
Example 12
Synthesis of (6-methoxy-2-methyl-3a,7a-dihydro-benzofuran-3-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 12)
[0082] A mixture of 6-methoxybenzofuran-3-carbaldehyde (0.600 g, 3.41 mmol), HOCH 2 CH 2 OH (3.17 g, 51 mmol) and p-toluenesulfonic acids (0.001 g) in benzene (20 mL) was refluxed for 8 h using a Dean-Stark water trap. The mixture was concentrated under reduced pressure and then diluted with EtOAc. The organic solution was washed with water, dried over anhydrous MgSO 4 , and concentrated to give 3-(1,3-dioxolan-2-yl)-6-methoxybenzofuran (0.711 g, 95%)
[0083] 3-(1,3-Dioxolan-2-yl)-6-methoxybenzofuran (0.144 g, 0.65 mmol) was dissolved in THF (5 mL) at −30 to −20° C. To this solution was added dropwise tert-butyllithium (15% in pentane, 0.56 mL, 1.31 mmol). The reaction mixture was continuously stirred at −30° C. for 30 min and then allowed to warm to 0° C. and stir for another 20 min. The reaction mixture was cooled to −30° C. again and iodomethane (0.138 g, 0.98 mmol) was added dropwise. After stirring at −30° C. for another 1 h, it was allowed to warm to room temperature overnight. After the solvent was removed under reduced pressure, the residue was dissolved in EtOAc and washed with saturated NaHCO 3 . The aqueous layer was extracted with EtOAc (3×20 mL). The combined organic layers were dried over anhydrous MgSO 4 and concentrated under reduced pressure to provide 3-[1,3]dioxolan-2-yl-6-methoxy-2-methyl-benzofuran.
[0084] 2N HCl (5 mL) was added to 3-[1,3]dioxolan-2-yl-6-methoxy-2-methyl-benzofuran in THF (5 mL) at 0° C. After stirring for 1 h at room temperature, the solvent was removed under reduced pressure. The residue was dissolved in EtOAc and washed with saturated NaHCO 3 . The aqueous layer was extracted with EtOAc (3×20 mL). The organic layers were combined and dried over anhydrous MgSO 4 . After the solvent was removed, the residue was purified on a silica gel column eluting with EtOAc/hexane (1:9) to give 6-methoxy-2-methylbenzofuran-3-carbaldehyde (0.090 g, 81%).
[0085] 6-Methoxy-2-methylbenzofuran-3-carbaldehyde was coupled with 3,4,5-trimethoxybromobenzene and subsequently oxidized by MnO 2 in a manner similar to that described in Example 11 to afford compound 12.
[0086] 1 H NMR (300 MHz, CDCl 3 ) δ 2.55 (s, 3H, —C H 3 ), 3.85 (s, 6H, —OC H 3 ), 3.86 (s, 3H, —OC H 3 ), 3.95 (s, 3H, —OC H 3 ), 6.85 (dd, 1H, J=9, 2.4 Hz), 7.01(d, 1H, J=2.4 Hz), 7.12 (s, 2H), 7.34 (d, 1H, J=9 Hz).
Example 13
Synthesis of (6-methoxy-3a,7a-dihydro-benzo[b]thiophen-3-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 13)
[0087] 6-Methoxy-3-methylbenzo[b]thiophene was prepared using the method described in Campaigne et al., J Heterocycl Chem, 1970, 7, 695.
[0088] A mixture of 6-methoxy-3-methylbenzo[b]thiophene (2.753 g, 15.5 mmol) and SeO 2 (2.06 g, 18.55 mmol) in 1,4-dioxane (30 mL) was refluxed for 2 days and then filtered. The filtrate was concentrated in vacuo, and the residue was purified on a silica gel column eluting with EtOAc/hexane (1:10) to give 6-methoxybenzo[b]thiophene-3-carbaldehyde (2.3 g, 80%).
[0089] The resulting product was then coupled with 3,4,5-trimethoxybromobenzene and then oxidized by MnO 2 in a manner similar to that described in Example 11 to afford compound 13 at a yield of 54%.
[0090] 1 H NMR (300 MHz, CDCl 3 ) δ 3.89 (s, 6H, —OC H 3 ), 3.91 (s, 3H, —OC H 3 ), 3.95 (s, 3H, —OC H 3 ), 7.13 (dd, 1H, J=9, 2.4 Hz), 7.14 (s, 2H), 7.36(d, 1H, J=2.4 Hz), 7.85 (s, 1H), 8.37 (d, 1H, J=9 Hz).
Example 14
Synthesis of (6-methoxy-2-methyl-3a,7a-dihydro-benzo[b]thiophen-3-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 14)
[0091] 6-Methoxybenzo[b]thiophene-3-carbaldehyde was converted to 3-(1,3-dioxolan-2-yl)-6-methoxybenzo[b]thiophene according to the method described in Example 12.
[0092] The resulting product was then coupled with 3,4,5-trimethoxybromobenzene and then oxidized by MnO 2 in a manner similar to that described in Example 11 to afford compound 14 at a yield of 79%.
[0093] 1 H NMR (300 MHz, CDCl 3 ) δ 2.49 (s, 3H, —C H 3 ), 3.82 (s, 6H, —OC H 3 ), 3.87 (s, 3H, —OC H 3 ), 3.95 (s, 3H, —OC H 3 ), 6.92 (dd, 1H, J=9, 2.4 Hz), 7.12 (s, 2H), 7.26(d, 1H, J=2.4 Hz), 7.44 (d, 1H, J=9 Hz).
Example 15
Synthesis of (6-methoxy-pyrazolo[1,5-b]pyridazin-3-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 15)
[0094] A solution of 3,4,5-trimethoxybenzaldehyde (1.0 g, 5.0 mmol) in THF (50 mL) was stirred at 0° C. Sodium acetylide (18% w.t. slurry in xylene, 1.63 g, 6.1 mmol) was added via syringe. The reaction mixture was stirred overnight at room temperature and quenched by water. It was then extracted with EtOAc (30 mL×3). The combined organic layers were washed with brine, dried over anhydrous MgSO 4 , filtered, and concentrated to give a crude product, which was purified by flash column chromatography eluting with EtOAc/n-hexane (1:2) to afford 1-(3,4,5-trimethoxyphenyl)prop-2-yn-1-ol as a white solid (815 mg, 72%).
[0095] To a stirred solution of 1-(3,4,5-trimethoxyphenyl)prop-2-yn-1-ol (100 mg, 0.44 mmol) in acetone (10 mL), aqueous Jones reagent was added dropwise at 0° C. until the red color persisted. The reaction mixture was quenched by 2-propanol, and the precipitate was were removed by filtered through Celite. The filtrate was diluted with EtOAc, washed several times with a saturated aqueous NaHCO 3 solution, water and brine, dried over MgSO 4 , and concentrated to give crude product, which was purified by flash chromatography eluting with EtOAc/n-hexane (1:4) to afford 1-(3,4,5-trimethoxyphenyl)prop-2-yn-1-one as a colorless oil (74 mg, 75%).
[0096] A mixture of 3-chloro-6-methoxypyridazine (1.0 g, 6.9 mmol) in methanol (50 mL) with 33% palladium on carbon (100 mg) was hydrogenated under 45 psi overnight. The catalyst was removed by filtration through a pad of Celite. The filtrate was concentrated and dissolved in EtOAc. The solution was washed several times with a saturated NaHCO 3 solution and brine, dried over MgSO 4 , concentrated to give a crude product, which was purified on a silica gel column eluting with EtOAc/n-hexane (1:2) to give 3-methoxypyridazine as a pale yellow solid (662 mg, 87%).
[0097] 1 H NMR (300 MHz, CDCl 3 ): δ 4.14 (s, 3H), 6.98 (dd, J=1.2, 9.0 Hz, 1H), 7.36 (dd, J=4.5, 8.7 Hz, 1H), 8.84 (dd, J=1.2, 4.5 Hz, 1H).
[0098] Potassium bicarbonate (2.5 M) was added to a solution of hydroxylamine-O-sulfonic acid (64.7 mg, 0.57 mmol) until the pH value turned to 5. Then, 3-methoxypyridazine (42 mg, 0.38 mmol) was added at 70° C. over 10 min. The mixture was stirred at 70° C. for 2 h and then cooled to room temperature. The pH value of the mixture was adjusted to 8 by addition of 2.5M potassium bicarbonate. 1-(3,4,5-Trimethoxyphenyl)prop-2-yn-1-one (42 mg, 0.19 mmol) in CH 2 Cl 2 (10 mL) and potassium hydroxide (40 mg, 0.71 mmol) were added. The mixture was stirred at room temperature overnight, and then was extracted with CH 2 Cl 2 , and the combined organic layers were washed with brine, dried over MgSO 4 , and concentrated to give a crude product, which was purified on a silica gel column eluting with CH 2 Cl 2 /MeOH (20:1) to afford compound 15 as a white solid (31 mg, 48%).
[0099] 1 H NMR (300 MHz, CDCl 3 ): δ 3.93 (s, 6H), 3.95 (s, 3H), 4.11 (s, 3H), 7.00 (d, J=9.3 Hz, 1H), 7.15 (s, 2H), 8.23 (s, 1H), 8.56 (d, J=9.6 Hz, 1H).
Example 16
Synthesis of (2-methoxy-7H-pyrrolo[2,3-d]pyrimidin-5-yl)-(3,4,5-trimethoxy-phenyl)-methanone (compound 16)
[0100] 10% Pd/C (1.000 g, 11.6 mmol) was added to a solution of 4-chloro-2-methoxy-7H-pyrrolo[2,3-d]pyrimidine (0.200 g, 1.09 mmol) in 20 mL anhydrous MeOH under H 2 at room temperature. The mixture was stirred for 8 h and then filtered through a pad of Celite. The filtrate was concentrated in vacuo to give 2-methoxy-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidine as a major product.
[0101] MnO 2 (1.720 g, 20 mmol) was added to 2-methoxy-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidine in 20 mL of anhydrous CH 2 Cl 2 at room temperature. The mixture was stirred for 8 h, diluted with anhydrous ether (50 mL), and filtered through a pad of Celite. The filtrate was concentrated in vacuo, and the residue was purified on a silica gel column eluting with MeOH/CH 2 Cl 2 (1:9) to give 2-methoxy-7H-pyrrolo[2,3-d]pyrimidine (0.149 g, 90%).
[0102] To a mixture of 2-methoxy-7H-pyrrolo[2,3-d]pyrimidine (0.220 g, 1.476 mmol) and anhydrous zinc chloride (0.407 g, 2.953 mmol) in dry CH 2 Cl 2 (20 mL), ethylmagnesium bromide (0.65 mL, 3.0 M solution in diethyl ether) was added over 10 min at room temperature. The suspension was stirred for 1 h, and then 3,4,5-trimethoxybenzoyl chloride (0.510 g, 2.2 mmol) in dry CH 2 Cl 2 (10 mL) was added dropwise over 5 min. The reaction mixture was stirred for another 1 h and then aluminum chloride (0.196 mg, 1.476 mmol) was added. The resulting thick mixture was vigorously stirred for 5 h. The reaction was quenched with water (10 mL) and extracted with CH 2 Cl 2 (20 mL). The combined organic layers were dried over anhydrous MgSO 4 and evaporated to give a brown oil, which was purified on a silica gel column (EtOAc:Hexane=1:1 to MeOH:CH 2 Cl 2 =1:20) to give compound 16 (0.081 g, 20%).
[0103] 1 H NMR (300 MHz, CDCl 3 ) δ 3.93 (s, 6H, —OC H 3 ), 3.95 (s, 3H, —OC H 3 ), 4.09 (s, 3H, —OC H 3 ), 7.13 (s, 2H), 7.71(d, 1H, J=2.4 Hz), 9.38 (s, 1H), 9.79 (s, 1H).
Example 17
Cell Growth Inhibition Assay
[0104] KB cells (a cell line derived from a human carcinoma of the nasopharynx) and MKN-45 cells (a gastric cancer cell line) were maintained in plastic dishes in RPMI 1640 medium supplemented with 5% fetal bovine serum. The KB cells were seeded in 96-well plates at a final cell density of 7,000 cell/mL. The MKN-45 cells were seeded in 96-well plates at a final cell density of 20,000 cell/mL. The cells were treated with a test compound (at least five different concentrations for the test compound), and incubated in a CO 2 incubator at 37° C. for 72 h. The number of viable cells was estimated using the MTS assay (or the methylene blue assay) and absorbance was measured at 490 nm. Cytotoxicity of the test compounds was expressed in terms of IC 50 values. The values represent averages of three independent experiments, each with duplicate samples.
[0105] Compounds 1-14 were tested in the above assay. All of them effectively inhibited growth of KB cells and MKN-45 cells. Unexpectedly, most of them exhibited IC 50 values lower than 1 mM, some even lower than 100 nM.
Example 18
Tubulin Polymerization Assay
[0106] Turbidimetric assays of microtubule are performed according to the procedure described by Lopes et al. (1997, Cancer Chemother. Pharmacol. 41: 37-47) with some modifications. MAP-rich tubulin (2 mg/ml) is preincubated in a polymerization buffer (0.1 M PIPES, pH 6.9, 1 mM MgCl 2 ) with a test compound at 4° C. for 2 min before the addition of 1 mM GTP. The samples are then rapidly warmed to 37° C. in a 96-well plate thermostatically controlled spectrophotometer and measuring the change at 350 nm with time.
Example 19
Cell Growth Inhibition Assay on Multiple-Drug Resistant Human Cancer Cell Lines
[0107] Several fused bicyclic heteroaryl compounds of this invention are tested against several panels of drug-resistant cell lines. It is well known that several anti-mitotic agents, including vinca alkaloid (e.g., vincristine and vinblastine) and taxol, have been used to treat various human cancers. Vinca alkaloid resistance has been attributed to a number of mechanisms associated with the multi-drug resistance (MDR) phenotype, including overexpression of p-glycoprotein and multi-drug resistant-associated protein (MRP). The mechanisms responsible for taxol resistance include overexpression of p-glycoprotein and mutation of tubulin. For comparison, five anti-mitotic agents, i.e., vincristine, VP-16, cisplatin, camptothecin, and taxol, are also tested against several panels of drug-resistant cell lines e.g., KB-Vin10 (a vincristine-resistant cell line), KB100 (a camptotnecin-resistant cell line), and CPT30 (a camptothecin-resistant cell line).
Example 20
CAM Assay for Antiangiogenic Potency
[0108] Each test compound is dissolved in a 2.5% aqueous agarose solution (final concentration: 1-20 mg/mL). 10 μL of the solution are applied dropwise on circular Teflon pallets of 3 mm in diameter and then cooled to room temperature at once. After incubation at 37° C. and relative humidity of 80% for 65-70 h, fertilized hen eggs are positioned in a horizontal position and rotated several times. Before opening the snub side, 10 mL of albumin are aspirated from a hole on the pointed side. At two-third of the height (from the pointed side), the eggs are traced with a scalpel and the shells are removed with forceps. After the aperture (cavity) has been covered with keep-fresh film, the eggs are incubated at 37° C. at a relative humidity of 80% for 75 h. When the chorioallantoic membrane approximates a diameter of 2 cm, one pellet (1 pellet/egg) is placed on it. The eggs are incubated for 1 day and subsequently evaluated under the stereomicroscope.
Other Embodiments
[0109] All of the features disclosed in this specification may be combined in any combination. Each feature disclosed in this specification may be replaced by an alternative feature serving the same, equivalent, or similar purpose. Thus, unless expressly stated otherwise, each feature disclosed is only an example of a generic series of equivalent or similar features.
[0110] From the above description, one skilled in the art can easily ascertain the essential characteristics of the present invention, and without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions. For example, compounds structurally analogous to the fused bicyclic heteroaryl compounds of this invention also can be made, screened for their inhibitory activities against cancer cell growth, and used to practice this invention. Thus, other embodiments are also within the claims. | Compounds of the following formula:
wherein A, D, Q, T, U, V, W, X, Y, Z, R 1 , and ---- are as defined herein. This invention also relates to a method of inhibiting tubulin polymerization, or treating cancer or an angiogenesis-related disorder with one of these compounds. | 0 |
We, Karsten Buhr, a citizen of Germany, residing at Willroth, Germany, Stefan Abresch, a citizen of Germany, residing at Dierdorf, Germany, Thomas Lehnert, a citizen of Germany, residing at Oberraden, Germany, Guenter Haehn, a citizen of Germany, residing at Koenigswinter, Germany, and Cyrus Barimani, a citizen of Germany, residing at Koenigswinter, Germany have invented a new and useful “Ejector Unit For A Road Milling Machine Or The Like”. This application claims priority from German Patent Applications No. 10 2009 014 730.6-25 and No. 10 2009 014 729.2-25, both filed Mar. 25, 2009.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an ejector unit, in particular for a road milling machine, having an ejector that comprises a conveying surface.
2. Description of the Prior Art
Road milling machines usually comprise a milling tube on whose surface are mounted a plurality of bit holders. The bit holders are usually part of a bit holder changing system that also encompasses a base part. The base part is welded onto the surface of the milling tube, and replaceably receives the bit holders. The bit holder serves for mounting of a cutting bit, usually a round-shaft cutting bit, as known e.g. from published German patent application DE 37 01 905 C1. The bit holders are arranged on the surface of the milling tube so as to yield spiral-shaped helices. The helices proceed from the edge region of the milling tube and rotate toward the center of the milling tube.
The respective helices that proceed from the oppositely located edge regions therefore meet at the center of the milling tube. One or more ejectors are also then arranged in this region. The helices convey to the ejectors the material removed by the cutting bits. The ejectors then transport it out of the working region of the milling tube.
The ejectors are subject to severe abrasive attack, and must therefore be regularly checked and replaced. For this, the ejector welded onto the milling tube must be detached and a new one welded on. Attention must be paid to the exact positioning and alignment of the ejector in order to achieve ideal discharge performance. This replacement work in the confined working area of the milling tube is laborious.
SUMMARY OF THE INVENTION
It is an object of the invention to make available an improved ejector unit and ejector that enable simple machine maintenance.
1. The Ejector Unit
The ejector unit includes an ejector replaceably mountable on a carrying part. This results in a tool system in which the ejector can be easily and quickly replaced in the event of damage or wear. Work is thereby considerably simplified, and machine downtimes can be considerably reduced.
According to a preferred variant embodiment of the invention, provision can be made that the ejector is mountable on the carrier in at least two different operating positions.
The ejectors can be used in one operating position until the wear limit is reached. The ejector is then brought into the next operating position and can then be used further. This results in a service life for the ejector that is considerably extended as compared with usual ejectors.
Provision can be made in this context that in order to change the operating positions, the ejector is installed having been rotated 180 degrees. What is exploited here is the recognition that the ejector wears substantially on its region facing away from the milling tube. Once the wear state has been reached there, the ejector is detached and is reinstalled having been rotated 180 degrees. The ejector service life can thereby be considerably extended, ideally in fact doubled. In order to lose as little time as possible when changing the operating positions of the ejector, and to make installation unequivocal, provision can be made that the ejector and the holder form a mechanical interface that enables reversible installation of the ejector.
Secure mounting of the ejector on the carrier part results from the fact that the ejector comprises a mounting receptacle and/or a mounting extension, and that the ejector is connected indirectly or directly to the carrier by means of one or more mounting elements.
One conceivable inventive alternative is such that the ejector is braced in planar fashion on a support surface of the carrier by means of a mounting side, that the ejector comprises a securing extension and/or a securing receptacle, and that the securing extension engages into a securing receptacle of the carrier and/or a securing extension of the carrier engages into the securing receptacle of the ejector. The mutually interengaging connection of the securing extension and securing receptacle creates a positively engaged connection through which processing forces can be dissipated in load-optimized fashion. This becomes possible in particular when provision is made that the positively engaged connection impedes or blocks any offset of the ejector with respect to the carrier transversely to the feed direction.
In the context of the ejector unit according to the present invention, provision can be made that the carrier comprises a mounting foot onto which is shaped a support part, and that the mounting foot comprises a mounting surface extending substantially in the feed direction. By means of the mounting surface, the carrier can be positioned correctly on the milling tube and mounted thereon, in particular welded on.
The carrier can be produced in simple fashion as an economical component.
If provision is made that the mounting foot is widened with respect to the support part in or oppositely to the feed direction, a load-optimized geometry then results. The transition region between the support part and the mounting foot is exposed to large bending stresses in the tool insert. Widening decreases the material stresses at that point.
According to a preferred variant embodiment of the invention, provision can be made that the ejector comprises a conveying surface that is arranged substantially transversely to the feed direction of the ejector unit, and is embodied in hollowed fashion, in particular recessed in scoop-like fashion, at least locally in a direction opposite to the tool feed direction. This hollowed conformation enables a geometry that improves the discharge rate.
If provision is made that one or more depressions are introduced into the conveying surface, material removed during tool use can become deposited in the depressions. A “natural” wear protection layer forms there.
According a variant of the invention, provision can be made that at least one screw receptacle is used as a mounting receptacle, and that the screw receptacle opens, toward the front side of the ejector, into a screw head receptacle in which a screw head of a mounting screw is at least locally nonrotatably receivable. Rapid and problem-free ejector replacement is possible with the screw connections. Countersunk or partly countersunk reception of the screw head prevents abrasive attack on the countersunk head region. In addition, loosening of the screw at this point is prevented.
If the conformation of the ejector is such that one or more shaped-on stiffening ribs are arranged on the rear side facing away from the conveying surface, a sufficiently rigid ejector can then be designed with little material outlay.
A preferred variant of the invention is such that the mounting side comprises a convex mounting portion for contact against a concave receiving portion of a carrier. This results in a surface connection between the carrier and the ejector through which processing forces can be reliably dissipated even in the event of asymmetrical force application to the conveying surface.
If provision is made that the carrier holds the ejector in such a way that the conveying surface extends with a slight inclination with respect to the feed direction, the discharge performance can then be optimized. It has been shown that particularly good performance is achieved with an inclination setting in an angle range of +/−20 degrees. Surprisingly, an optimum is obtained at a negative inclination angle, specifically at an inclination of 5 to 15 degrees opposite to the feed direction.
An additional improvement in ejector service life is achieved by the fact that at least one wear protection element, made of a material more wear-resistant than the conveying surface, is arranged in the region of the conveying surface; provision can be made in particular that the wear protection element is constituted by a hard-material element or by a hardfacing.
2. The Ejector
The ejector comprises a mounting side, facing away from its conveying surface, having a support surface. With this mounting side, the ejector can be placed onto a component mounted on the milling tube, for example onto a carrying part welded thereon. By way of the support surface of the carrying part, the loads occurring during tool use are reliably dissipated at least in part. The ejector is equipped with a mounting receptacle or mounting extension, so that it is replaceably mountable. In this fashion it can easily be changed in the event of damage or wear.
According to a preferred variant embodiment of the invention, provision can be made that the conveying surface of the ejector is arranged transversely to the feed direction of the ejector unit, and is at least locally embodied in concave fashion or is assembled, in the hollowed region, from line segments and/or curve segments. The concave or hollowed conformation enables a scoop-like geometry that improves the discharge rate.
To allow the ejector to be reliably braced on a carrying part, provision can be made that at least one protruding securing extension, or a recessed securing receptacle, is arranged on the side facing away from the conveying surface. Transverse forces that occur can then be transferred, in particular, in positively engaged fashion from the ejector into the carrying part. This is possible in particular when provision is made that by means of the at least one securing extension or the at least one securing receptacle, any displacement of the ejector in a plane transverse to the feed direction can be limited in positively engaged fashion.
Provision can be made according to the present invention that the screw receptacle is guided through the securing extension or securing receptacle. The carrying part is then utilized for a sufficient clamping length of the mounting screw.
A preferred configuration of the invention is such that the mounting side is embodied in such a way that the ejector is installable in different operating positions. The ejector can, in particular, be embodied in mirror-symmetrical fashion, or can be embodied in the region of a mounting side in such a way that it enables installation reversibly in two different operating positions. Also conceivable is an ejector that enables three or four different operating positions.
This is based on the recognition that the ejector becomes worn substantially on its region facing away from the milling tube. Once the worn state is achieved there, the ejector is removed and put back on having been rotated, for example, 180 degrees.
A preferred configuration of the invention is such that the mounting side comprises a convex or crowned or spherical mounting portion for contact against a concave or hollowed receiving portion of a carrier. This connection creates a large connecting surface that ensures good energy transfer even when the conveying surface is asymmetrically loaded. A further improvement in service life is achieved by the fact that at least one wear protection element, made of a material more wear-resistant than the conveying surface, is arranged in the region of the conveying surface. In this context, provision can be made in particular that the wear protection element is constituted by a hard-material element, for example carbide or ceramic, or by an applied coating, for example a hardfacing.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be further explained below with reference to an exemplifying embodiment depicted in the drawings, in which:
FIG. 1 is a front view of a milling drum of a road milling machine;
FIG. 2 is a side view of the milling drum according to FIG. 1 ;
FIG. 3 shows the view according to FIG. 2 , enlarged and with a slightly modified depiction;
FIG. 4 is a perspective front view of an ejector unit;
FIG. 5 is a perspective rear view of the ejector unit according to FIG. 4 ;
FIG. 6 is a perspective rear view of a carrier of the ejector unit according to FIG. 5 ;
FIG. 7 is a front perspective view of the carrier according to FIG. 6 ;
FIG. 8 is a perspective front view of an ejector of the ejector unit according to FIG. 4 ;
FIG. 9 is a perspective rear view of the ejector according to FIG. 8 ;
FIG. 10 is a perspective rear view of a second embodiment of an ejector unit having an ejector and a carrier; and
FIG. 11 is a perspective front view of the arrangement according to FIG. 10 .
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a milling drum having a cylindrical milling tube 10 onto whose drum surface 10 . 1 are welded a plurality of base parts 11 of bit holder changing systems. Base parts 11 carry replaceable bit holders 12 . A cutting bit 13 , specifically a round-shaft cutting bit, is replaceably received in each bit holder 12 . Base parts 11 are arranged with respect to one another so that they form a helix, specifically a transport helix. The helix rotates, proceeding from the side of milling tube 10 on drum surface 10 . 1 , toward the milling tube center formed between the two sides. For better clarity, only some of the bit holder changing systems are depicted in FIGS. 1 and 2 . Dashed lines that represent the center longitudinal axis of cutting bits 13 are shown as substitutes for the bit holder changing systems (not shown). As is evident from these lines, multiple transport helices are located on either side of the milling tube center.
The transport helices meet in pairs in the region of the milling tube center. As is evident from FIG. 1 , at least one respective ejector unit is arranged there. FIG. 3 , as compared with the depiction in FIG. 2 , does not show the bit holder changing systems, redirecting attention to the ejector unit. As is evident from this depiction, the ejector unit is constituted by a carrying part 30 and an ejector 20 .
FIGS. 4 and 5 show the ejector unit in isolation.
Firstly the design of carrying part 30 will be explained with reference to FIGS. 6 and 7 . Said part comprises a mounting foot 31 that forms on its underside a mounting surface 33 . With this, carrying part 30 can be placed onto drum surface 10 . 1 and welded at the sides. Shaped onto mounting foot 31 is an upwardly projecting support part 35 that forms a rear side 36 . Mounting foot 31 is widened by means of an extension 32 over rear side 36 , so that it forms a wide mounting surface 33 having a large support spacing. The widened cross section produced by extension 32 furthermore brings about a reinforcement of the highly stressed transition region between mounting foot 31 and carrying part 35 . A further widening of mounting surface 33 is achieved with a front-side protrusion 34 that, like extension 32 , extends over the entire width of carrying part 30 . Carrying part 30 comprises on the front side a support surface 37 that extends over the front side of carrying part 35 and also over part of mounting foot 31 . This embodiment of support surface 37 enables strength-optimized bracing of ejector 20 . Two receptacles 37 . 1 , 37 . 2 are inset into support surface 37 . The two receptacles 37 . 1 , 37 . 2 are recessed into support surface 37 so that they form trough-like hollows.
Ejector 20 will be explained below with reference to FIGS. 8 and 9 . It is embodied in plate-shaped fashion as a drop forged part, and is therefore particularly rigid. Ejector 20 comprises a front-side conveying surface 21 .
Said surface is equipped with recesses 21 . 1 , 22 . Located between recesses 21 . 1 are ribs that are at an angle to the vertical and are thus inclined toward the center of the ejector. The recesses receive removed material during operational use, thus forming a “natural” wear protector. A particularly good conveying rate is furthermore achieved by the fact that conveying surface 21 is embodied in concave, and thus scoop-shaped, fashion. Recess 22 comprises two oblique surfaces 22 . 1 that are at an angle to conveying surface 21 and assist the conveying action.
Located between the two recesses 22 is a thickened extension 23 that receives two screw receptacles 29 embodied as through holes. Screw receptacles 29 transition on the front side into hexagonal screw head receptacles 29 . 1 .
FIG. 9 shows the rear side of ejector 20 . As is evident from this depiction, rib-like securing extensions 26 . 1 , 26 . 2 project from ejector 20 on the rear side. Securing extensions 26 . 1 and 26 . 2 are adapted, in terms of their arrangement and dimensioning, to the arrangement and shape of receptacles 37 . 1 and 37 . 2 of carrier 30 . Screw receptacles 29 are guided through securing extension 26 . 1 .
As is further evident from FIG. 9 , stiffening ribs 27 are arranged in the rear-side corner regions of ejector 20 . Said ribs are connected to the horizontal securing extension 26 , thus yielding optimum energy dissipation.
In order to mount ejector 20 , it is placed with its rear side onto support surface 37 of carrier 30 . Securing extensions 26 . 1 , 26 . 2 then engage into the corresponding receptacles 37 . 1 , 37 . 2 . This results in a crosswise splining that prevents any displacement of ejector 20 with respect to carrier 30 in the axial and radial direction of milling tube 10 . By way of this splined connection, large portions of the forces occurring during tool use can be dissipated.
Screw receptacles 29 , 36 . 1 of ejector 20 and of carrier 30 are in alignment, so that mounting screws 24 (see FIGS. 4 and 5 ) can be inserted through them. The screw head of mounting screws 24 is accommodated in screw head receptacle 29 . 1 , where it is held nonrotatably. Preferably self-locking nuts 28 can be screwed onto mounting screws 24 , and ejector 20 can thus be secured on carrier 30 .
It is chiefly the radially projecting region of ejector 20 that wears during tool use. As is evident from FIGS. 8 and 9 , ejector 20 is embodied symmetrically with respect to the center transverse plane. When the wear limit is reached, it can therefore be removed and put back on having been rotated 180 degrees.
FIGS. 10 and 11 show a further variant embodiment of an ejector unit according to the present invention. Said unit once again encompasses an ejector 20 and a carrier 30 . Ejector 20 again possesses a hollowed conveying surface 21 that faces in the processing direction, the hollow being recessed concavely in a direction opposite to the processing direction. Facing away from conveying surface 21 , ejector 20 comprises on its rear-side mounting side 25 a mounting extension 20 . 1 . The latter protrudes in block fashion oppositely to the processing direction. It possesses two screw receptacles that can be arranged in alignment with screw receptacles of carrier 30 .
Mounting screws 24 can be passed through the screw receptacles, and nuts 28 can be threaded onto their threaded studs. Ejector 20 is thereby fixedly braced against a support surface 37 of carrier 30 . As is evident from the drawings, ejector 20 is equipped in the region of mounting side 25 with cutouts 20 . 2 . Upper cutout 20 . 2 receives the heads of mounting screws 24 and thus protects them, behind conveying surface 21 , from the abrasive attack of the removed material. Lower cutout 20 . 2 extends in skirt fashion over carrier 30 and protects it there. Ejector 20 is symmetrical with respect to the central transverse axis, and can therefore be mounted reversibly in two operating positions, rotated 180 degrees, on carrier 30 .
FIG. 3 is an end view of the milling tube 10 which can also be referred to as a milling drum 10 . The milling drum 10 rotates in the feed direction indicated by the arrow V. The milling drum rotates about an axis indicated by the + in the center of the milling drum in FIG. 3 . Directions generally parallel to the rotational axis may be referred to as axial directions and directions extending generally radially outward from the axis may be referred to as radial directions. Both the axial and radial directions can be considered to be generally transverse to the feed direction V.
The ejector 20 seen in perspective in FIGS. 8 and 9 , and in end view in FIG. 3 , can be described as being generally rectangular in shape having a width which extends in a generally radial direction and a length extending in a generally axial direction. The conveying surface 21 of the ejector 20 may be described as generally forward facing or as facing in the working direction V.
As best seen in FIG. 3 , the carrier 30 may support the ejector 20 at an angle α to a radius of the milling drum, which angle may be in a range of +/−20 degrees, and more preferably a negative angle from about −5 degrees to about −20 degrees. | The invention relates to an ejector unit, in particular for a road milling machine, having an ejector that is replaceably mounted on a carrier. In one aspect the ejector is curved in a scoop-like fashion. In another aspect the ejector is reversible upon the carrier to allow the ejector to be reversed after one wear surface is worn, thus presenting a new second wear surface. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to fluid delivery devices for infusion of beneficial agents into a patient. More particularly, the invention concerns a fluid delivery apparatus which includes a conformable ullage and a novel fill assembly for filling the fluid reservoir of the apparatus in the field.
2. Discussion of the Invention
Many medicinal agents require an intravenous route for administration thus bypassing the digestive system and precluding degradation by the catalytic enzymes in the digestive tract and the liver. The use of more potent medications at elevated concentrations has also increased the need for accuracy in controlling the delivery of such drugs. The delivery device, while not an active pharmacologic agent, may enhance the activity of the drug by medicating its therapeutic effectiveness. Certain classes of new pharmacologic agents possess a very narrow range of therapeutic effectiveness, for instance, too small a dose results in no effect, while too great a dose results in toxic reaction.
In the past, prolonged infusion of fluids has generally been accomplished by gravity flow methods, which typically involve the use of intravenous administration sets and the familiar bottle suspended above the patient. such methods are cumbersome, imprecise and require bed confinement of the patient. Periodic monitoring of the apparatus by the nurse or doctor is required to detect malfunctions of the infusion apparatus.
One of the most versatile and unique fluid delivery apparatus developed in recent years is that developed by one of the present inventors and described in U.S. Pat. No. 5,205,820.The components of this novel fluid delivery apparatus generally include: a base assembly, an elastomeric membrane serving as a stored energy means, fluid flow channels for filling and delivery, flow control means, a cover, and an ullage which comprises a part of the base assembly. The ullage in these devices, that is the amount of the fluid reservoir or chamber that is not filled by fluid, is provided in the form of a semi-rigid structure having flow channels leading from the top of the structure through the base to inlet or outlet ports of the device. Since the inventions described herein represent improvements over those described in U.S. Pat. No. 5,205,820 this patent is hereby incorporated by reference as though fully set forth herein.
In the semi-rigid ullage configuration described in U.S. Pat. No. 5,205,820, wherein the ullage means is more fully described, the stored energy means of the device must be superimposed over the ullage to form the fluid-containing portion of the reservoir from which fluids are expelled at a controlled rate by the elastomeric membrane of the stored energy means tending to return to a less distended configuration in the direction toward the ullage. With these constructions, the stored energy membrane is typically used at higher extensions over a significantly large portion of the pressure-deformation curve.
For good performance, the elastomeric membrane materials selected for construction of the stored energy membrane must have good memory characteristics under conditions of high extension; good resistance to chemical and radiological degradation; and appropriate gas permeation characteristics depending upon the end application to be made of the device. Once an elastomeric membrane material is chosen that will optimally meet the desired performance requirements, there still remain certain limitations to the level of refinement of the delivery tolerances that can be achieved using the semi-rigid ullage configuration. These result primarily from the inability of the semi-rigid ullage to conform to the shape of the elastomeric membrane near the end of the delivery period. This nonconformity can lead to extended delivery rate tail-off and higher residual problems when extremely accurate delivery is required. For example, when larger volumes of fluid are to be delivered, the tail-off volume represents a smaller portion of the fluid amount delivered and therefore exhibits much less effect on the total fluid delivery profile, but in very small doses, the tail-off volume becomes a larger portion of the total volume. This sometimes places severe physical limits on the range of delivery profiles that may easily be accommodated using the semi-rigid ullage configuration.
As will be better appreciated from the discussion which follows, the apparatus of the present invention provides a unique, disposable fluid dispenser of simple but highly reliable construction that may be adapted to a wide variety of end use applications. A particularly important aspect of the improved apparatus is the incorporation of conformable ullages made of yieldable materials which uniquely conform to the shape of the stored energy membrane as the membrane distends and then returns to a less distended configuration. This novel construction, which permits the overall height of the device to be minimized, will satisfy even the most stringent delivery tolerance requirements and uniquely overcomes the limitation of materials selection. Further a plurality of subreservoirs can be associated with a single ullage thereby making it possible to incorporate a wide variety of delivery profiles within a single device.
The thrust of the present invention is to provide a novel fluid delivery apparatus that includes a conformable ullage of the character described in the preceding paragraph and also includes a unique fill assembly that can be used to controllably fill the fluid reservoir of the apparatus in the field. As will be better understood from the description which follows, the fill assembly of the present invention includes a fluid containing vial subassembly mounted within a unique adapter subassembly that functions to conveniently mate the vial subassembly with the conformable ullage type fluid delivery assembly.
In use, the adapter sub assembly of the invention securely interconnects the fluid containing vial with the fluid delivery assembly so that the reservoir of the device can be controllably filled with the fluid contained within the vial assembly. After the reservoir is thus filled, the stored energy means of the fluid delivery device will cooperate with the conformable ullage to controllably expel the fluid from the device.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a fluid delivery apparatus which embodies a stored energy source such as distendable elastomeric membrane which cooperates with a base and a conformable ullage to define a fluid reservoir and one which includes a unique fill assembly for use in controllably filling the fluid reservoir. The novel fill assembly of the invention enables the fluid reservoir of the fluid delivery portion of the apparatus to be aseptically filled in the field with a wide variety of selected medicinal fluids.
Another object of the present invention is to provide an apparatus of the aforementioned character in which the fill assembly comprises a vial assembly of generally conventional construction that can be prefilled with a wide variety of medicinal fluids.
Another object of the present invention is to provide a fill assembly of the type described in the preceding paragraph in which the prefilled vial subassembly is partially received within a novel adapter subassembly that functions to operably couple the vial subassembly with the fluid delivery portion of the apparatus.
Another object of the invention is to provide viewing means for viewing the amount of fluid remaining within the prefilled vial as the fluid reservoir is being filled.
Another object of the invention is to provide an adapter subassembly of the type described in which the body of the prefilled vial is surrounded by a protective covering to maintain the vial in an aseptic condition until immediately prior to mating the subassembly with the fluid delivery portion of the apparatus.
Another object of the invention is to provide an apparatus as described in the preceding paragraphs in which the adapter subassembly includes locking means for locking the subassembly to the fluid delivery portion of the apparatus following filling of the fluid reservoir thereof.
Another object of the invention is to provide a novel fill assembly which is easy to use, is inexpensive to manufacture, and one which maintains the prefilled vial in aseptic condition until time of use.
Another object of the invention is to provide an apparatus of the character described in the preceding paragraphs which embodies a soft, pliable, conformable mass which defines an ullage within the reservoir of the device which will closely conform to the shape of the stored energy membrane geometry thereby providing a more linear delivery and effectively avoiding extended flow delivery rate tail-off with minimum residual fluid remaining in the reservoir at end of the fluid delivery period.
Another object of the invention is to provide an apparatus of the character described which includes novel fluid rate control means for precisely controlling the rate of fluid flow from the device.
Another object of the invention is to provide an apparatus which, due to its unique construction, can be manufactured inexpensively in large volume by automated machinery.
Other objects of the invention are set forth in U. S. Pat. No. 5,205,820 which is incorporated herein by reference and still further objects will become apparent from the discussion which follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a generally perspective, exploded view of one form of the fluid delivery portion of the apparatus of the invention with which the adapter assembly of the invention can be operably interconnected.
FIG. 2 is a plan view of the fluid delivery portion shown in FIG. 1, partly broken away to show internal construction and shown coupled with the fill assembly of the apparatus.
FIG. 3 is a cross-sectional view taken along lines 3--3 of FIG. 2.
FIG. 4 is a cross-sectional view taken along lines 4--4 of FIG. 2.
FIG. 5 is a cross-sectional view taken along lines 5--5 of FIG. 2.
FIG. 6 is a cross-sectional view taken along lines 6--6 of FIG. 2.
FIG. 7 is a generally perspective view of one form of the adapter assembly of the present invention.
FIG. 8 is an enlarged, cross-sectional view of the adapter assembly illustrated in FIG. 7 as it appears in an assembled configuration.
FIG. 9 is a cross-sectional view similar to FIG. 8, but showing the appearance of the component parts of the invention after the plunger of the container has been telescopically moved from a first to a second position.
FIG. 10 is a cross-sectional view taken along lines 10--10 of FIG. 8.
DESCRIPTION OF THE INVENTION
Referring to the drawings and particularly to FIGS. 1 and 7, it is be observed that the apparatus of the invention comprises two major cooperating assemblies, namely the fluid delivery assembly 10 shown in FIG. 1 and the fill assembly 12 shown in FIG. 7. The fluid delivery assembly is similar in many respects to those disclosed in U. S. Pat. No. 5,205,820 in that it includes a base, a stored energy means which cooperates with the base to form a fluid reservoir and a cover assembly which overlays the base and encloses the stored energy means. However, unlike the fluid delivery apparatus disclosed in U.S. Pat. No. 5,205,820, which embodies semi-rigid ullages, the fluid delivery assembly of the present invention includes a novel conformable ullage, the character of which will presently be described. Also, unlike the fluid delivery devices shown in U.S. Pat. No. 5,205,820, the fluid delivery assembly of the present invention includes a uniquely configured receiving chamber 13 which is formed in the cover assembly (FIG. 1) and, in a manner presently to be described, telescopically receives a portion of the novel fill assembly of the invention.
Turning particularly to FIGS. 7 through 10, one form of the novel fill assembly portion of the apparatus is there shown and generally designated by the numeral 12. This form of the fill assembly comprises a container subassembly 14, an adapter assembly 15, and a cover assembly 17, the character of which will presently be described. Container subassembly 14 includes a body portion 16, having a fluid chamber 18 for containing an injectable fluid "F" provided with first and second open ends 20 and 22 (FIGS. 8 and 9). First open end 20 is sealably closed by closure means here provided in the form of a pierceable septum assembly 24. Septum assembly 24 is held securely in position by a clamping ring 24a. As best seen in FIGS. 8 and 9, a plunger 26 is telescopically movable within chamber 18 of container subassembly 14 from a first location shown in FIG. 8 where it is proximate first open end 22 to a second position shown in FIG. 9 where it is proximate first open end 20. The vial portion of the container subassembly 14 can be constructed of various materials such as glass and plastic.
Referring particularly to FIG. 7, it can be seen that the adapter subassembly 15 comprises a hollow housing 30 having a first open end 32 and a second closed end 34 (FIG. 9). Container subassembly 14 is telescopically receivable within open end 32 of housing 30 in the manner shown in FIG. 8 so that the housing can be moved from the first extended position shown in FIG. 8 to the second vial encapsulation position shown in FIG. 9. Forming an important part of the adapter subassembly is pusher means shown here as an elongated pusher rod 36 which functions to move plunger 26 within fluid chamber 18 from the first position shown in FIG. 8 to the second position shown in FIG. 9. In the form of the invention shown in the drawings, pusher rod 36 has a first end 36a interconnected with closure wall 34 and an opposite end 36b which engages plunger 26 and causes telescopic movement of the plunger within chamber 18 of container subassembly 14 as housing 30 is moved from the extended position into the vial encapsulating position shown in FIG. 9.
As best seen by referring to FIG. 10, the interior wall 31 of housing 30 is provided with circumferentially spaced-apart protuberances 40 which engage and center container subassembly 14 within housing 30. Due to the small surface area presented by protuberances 40, there is little frictional resistance to the sliding movement of container subassembly 14 relative to housing 30 as the housing is moved from the extended position shown in FIG. 8 into the vial encapsulating position shown in FIG. 9.
Cover subassembly 17 of the fill assembly of the present form of the invention includes a spiral wound, frangible portion 42 having a first open end 44 for telescopically receiving body portion 16 of container subassembly 14 (FIG. 8) and a second closed end 46. Portion 42 initially circumscribes a major portion of container subassembly 14 in the manner best seen in FIG. 8. An integral pull tab 42a is provided to permit the spiral wound, frangible portion to be pulled from container subassembly 14 so as to expose a substantial portion of body 16. As best seen in FIG. 7, a medicament label 50 circumscribes spiral wound portion 42 and serves to prevent accidental unwinding of the spiral portion from the container subassembly 14. However, upon pulling tab 42a, the spiral portion will unwind and, in so doing, will tear medicament label 50 so that the spiral portion 42 of the covering as well as a cylindrical portion 52 which, also comprises a part of the cover assembly, can be slipped from the container 14 so as to expose to view septum assembly 24.
As shown in FIGS. 7 and 8, the apertured end 52a of cylindrical portion 52 of subassembly 17 is provided with venting apertures 54 which are covered by a porous vent patch 56 which can be constructed from any suitable porous material that will permit air entrapped within the interior of cover subassembly 17 to be expelled to atmosphere as the subassembly is placed over container subassembly 14.
Turning once again to FIGS. 1 through 6, the fluid delivery assembly portion 10 of the apparatus can be seen to include a base subassembly 60, a cover subassembly 74 receivable over base subassembly 60, and a stored energy means, here provided in the form of a distendable membrane 66 (FIGS. 3 and 4). As best seen in FIGS. 3 and 4 the periphery of membrane 66 is sealably connected to an upraised portion 68 formed on base member 70. Base member 70 forms a part of base assembly 60 as does a clamping ring 72 which functions to clamp membrane 66 to upraised portion 68 (FIG. 1). Affixed to member 70 is a thin, planar shaped foam pad 71 having an adhesive coating provided on both its upper and lower surfaces. The adhesive coating on the upper surface of the pad enables the pad to be affixed to the lower surface of base member 70. As indicated in FIGS. 3 and 4, a peel strip 71a is connected to the bottom surface of foam pad 71 by the adhesive coating provided thereon. when the device is to be used, peel strip 71a can be stripped away from the pad so that the adhesive on the lower surface thereof can be used to releasably affix the apparatus of the invention to the patient's body.
Turning particularly to FIGS. 1 and 3, it can be seen that the cover subassembly 73 includes a cover member 74 and a medicament label 76. Cover member 73 is provided with the previously identified elongated receiving chamber 13 which is adapted to receive a portion of the fill subassembly of the invention. In a manner presently to be described the fluid container portion of the fill subassembly communicates via passageways 78, 80 and 81 with a fluid reservoir 82 which is uniquely formed between a deformable barrier member 83 and the upper surface 68a of upraised portion 68 of base member 70 (FIGS. 3 and 4). Disposed between barrier member 83 and distendable membrane 66 is the important conformable ullage means of the invention, the unique nature of which will presently be discussed.
Passageways 78 and 80 are formed within a housing 84 which is connected to cover member 73, while passageway 81 is formed within upraised portion 68 of base member 70. Housing 84 comprises a part of the cover subassembly of the invention and includes an outlet passageway 86 which communicates with a luer assembly 88 via flow control means generally designated by the numeral 90 (FIGS. 2 and 3). As best seen in FIG. 6, the flow control means here comprises an assemblage make up of four disc-like wafers. Wafers 94 and 96 of the assemblage comprise porous glass distribution frits while intermediate wafers 98 and 100 comprise a filter member and a rate control member respectively.
While filter member 98 can be constructed from a wide variety of materials, a material comprising polysulfone sold by Gelman Sciences under the name and style of SUPOR has proven satisfactory. Rate control member 100 is preferably constructed from a porous material such as polycarbonate material having extremely small flow apertures ablatively drilled by an excimer laser ablation process. Both the orifice size and unit distribution can be closely controlled by this process. However, a number of other materials can also be used to construct this permeable member, including metals, ceramics, cermet, plastics and glass. The rate control member can be specifically tailored to accommodate very specific delivery regimens including very low flow and intermediate flow conditions.
As best seen in FIGS. 2 and 5, housing 84 includes a generally cylindrically shaped hollow hub-like portion 102 which extends into receiving channel 13 when the housing 84 is mated with cover member 74. Formed within hub-like portion 102 is a hollow piercing cannula 104 the purpose of which will presently be described. As indicated in FIG. 2, the internal bore 104a of hollow cannula 104 comprises the previously identified fluid passageway 78, which is in fluid communication with flow passageway 80 of housing 84.
In using the apparatus of the invention, with the fill assembly in the filled configuration shown in FIG. 8, the cover subassembly is first removed from the container subassembly by pulling on pull-tab 42a. This will cause the spiral portion 42 of the cover subassembly to tear away from the container subassembly so that it can be separated from the forwardly disposed portion 52. Once the spiral wound portion 42 is removed, cylindrical portion 52 can also be removed and discarded. Removal of the cover subassembly exposes the forward portion of the container subassembly and septum 24 readies the adapter subassembly for interconnection with the fluid delivery assembly.
Prior to mating the adapter subassembly with the fluid delivery assembly, closure plug 106 of the cover subassembly must be removed in the manner illustrated in FIG. 1. This done, the fill assembly can be telescopically inserted into receiving chamber 13 and pushed forwardly in the direction indicated by the arrow 107 in FIG. 5. A force exerted in the direction of the arrow will cause the adapter subassembly to move to the right as viewed in FIG. 5 and will cause the piercing cannula 104 to pierce septum 24. Once a fluid flow path between fluid chamber 18 of the container subassembly 16 and the fluid reservoir 82 of the fluid delivery assembly is thus created, a continued movement of the adapter subassembly will cause pusher rod 36 to move plunger 26 forwardly of chamber 18 to a position shown in FIG. 5. As plunger 26 is moved forwardly of chamber 18, the fluid "F" contained within the chamber will flow through open end 20, into passageway 104a of the piercing cannula, passageway 80 of housing 84 and then into fluid reservoir 82 via passageway 81. As the fluid under pressure flows into reservoir 82, barrier member 83 will be distended outwardly in the manner shown in FIG. 4 and will uniformly deform the conformable ullage 77 and at the same time distend the distendable membrane 66 until it reaches the position shown in FIG. 4 where it engages inner wall 74a of cover member 74. Gases contained in the volume between wall 74a and the distendable membrane 66 will be vented to atmosphere via vent passageway "V" (FIG. 3). Ring 72, which is in clamping engagement with upstanding portion 68 of base 70 functions to capture and seal the distendable membrane against portion 68. In a similar manner, the periphery of the barrier member 83 is sealably affixed to the upstanding portion 68a of base 70 as by adhesive or thermal bonding bonding, so as to prevent leakage of fluid around the perimeter of the member.
It is to be understood that distendable membrane 66 can comprise a single film layer or can comprise a laminate construction made up of a number of cooperating layers. In this regard, reference should be made to columns 10 and 11 of U.S. Pat. No. 5,411,480 which patent is incorporated herein by reference, wherein the various materials that can be used to construct membrane 66 are discussed in detail. Reference should also be made to columns 11 and 12 of this patent for the various materials that can be used in the construction of the cover and base subassemblies of the fluid delivery apparatus of the present invention. Reference to FIG. 39 of the patent will show a distendable membrane of a laminate construction that can be used in the construction of the fluid delivery device of the present invention (see also columns 17 and 18 of U.S. Pat. No. 5,411,480).
Referring particularly to FIG. 1, it is to be noted that inlet means shown here as an inlet 111 formed in base 70 is provided to enable the introduction of gel which forms the conformable ullage of this form of the invention. Inlet 111 communicates with a fluid passageway 112 which, in turn, communicates with the volume defined between the under surface 66a of membrane 66 and the upper surface 83a of barrier member 83. Inlet 111 is sealably closed by a bonded plug 114.
With the construction described in the preceding paragraphs and as shown in FIGS. 3 and 4, the conformable mass 77, which comprises the ullage defining means of the invention is disposed within a chamber defined by the upper surface 68a of base member 68 and the inner surface or wall 74a of cover 74. Ullage 77 is, as shown in the drawings, in direct engagement with distendable membrane 66 which, after being distended, will tend to return to its less distended configuration. It is to be noted that the shape of the conformable ullage will continuously vary as the distendable membrane distends outwardly from the base during reservoir filling and then tends to return to its less distended configuration during fluid delivery.
While the conformable ullage, or mass 77 is here constructed from a flowable gel, the conformable ullage can also be constructed from a number of materials such as various types of foams, fluids and soft elastomers. In some instances, the conformable ullage may comprise an integral conforming mass. In other instances, such as when a gel or fluid is used as the ullage medium, an encapsulation barrier member such as member 83 must be used to encapsulate the gel or fluid and to provide an appropriate interface to the fluid contained in the reservoir.
Once reservoir 82 is filled with fluid from the container subassembly of the fill assembly, the fluid will remain in the reservoir until such time as the luer cap 89 is removed from luer assembly 88 so as to open the outlet flow path of the fluid delivery assembly. Once the outlet flow path of the assembly is opened, distendable membrane 66 will tend to return to its less distended configuration and will act upon the conformable ullage 77 and the barrier member 83 in a manner to cause fluid to flow from reservoir 82 outwardly through flow passageways 81 and 86 and then into the outlet port 120 of the device via the flow control means 90.
Referring once again to FIGS. 5 and 7, it is to be noted that hollow housing 30 includes locking means for locking the housing within receiving chamber 13 of cover 74 after the fill subassembly has been mated with the fluid delivery device. These locking means are here provided in the form of a series of forwardly and rearwardly disposed locking teeth 122 and 124 respectively. As indicated in FIG. 5, these locking teeth and constructed so that they will slide under a flexible locking tab 126, which is provided proximate the entrance of receiving chamber 13, as the adapter subassembly is urged inwardly of receiving chamber 13. However, once the adapter subassembly has reached the fully inserted position shown in FIG. 5 wherein the fluid is transferred to reservoir 82, locking tab 126 will effectively prevent removal of housing 30 of the adapter subassembly from passageway 13. With this novel construction, once reservoir 82 has been filled with the fluid contained in the container subassembly, the adapter subassembly cannot be removed from the fluid delivery device and, therefore, cannot be reused thereby preventing system adulteration.
Also forming an important aspect of the present invention is the provision of viewing means for viewing at any time the volume of fluid contained within chamber 18 of the fluid container subassembly 14. In the form of the invention shown in the drawings, this viewing means takes the form of an elongated viewing window 130 which is provided in housing 30 (FIG. 7). As indicated in FIG. 7, the body portion 16 of the container subassembly is provided with a plurality of longitudinally spaced-apart index lines, or marks 132, which can be viewed through window 130 as the container subassembly is urged forwardly of housing 30 in the manner previously described. Index lines 132 provide reference points for observing the volume of fluid remaining within the container subassembly. A protuberance 30a formed on housing 30 in cooperation with channel 30b (FIG. 5) functions to provide polarized orientation of the subassembly.
Having now described the invention in detail in accordance with the requirements of the patent statutes, those skilled in this art will have no difficulty in making changes and modifications in the individual parts or their relative assembly in order to meet specific requirements or conditions. Such changes and modifications may be made without departing from the scope and spirit of the invention, as set forth in the following claims. | A fluid delivery apparatus which embodies a stored energy source such as distendable elastomeric membrane which cooperates with a base and a conformable ullage to define a fluid reservoir and one which includes a unique fill assembly for use in controllably filling the fluid reservoir. The novel fill assembly of the invention enables the fluid reservoir of the fluid delivery portion of the apparatus to be aseptically filled in the field with a wide variety of selected medicinal fluids. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 61/998,400, filed Jun. 27, 2014, which is incorporated herein by reference.
FIELD
[0002] The present invention is generally related to construction or fabrication of optical devices, and more particularly, the present invention discloses methods of constructing or fabricating optical pathways as integral parts of a device structure that has essentially equivalent optical properties to conventional optical fibers.
BACKGROUND
[0003] In the field of optics and especially optical imaging, a number of devices are found, including, but not limited to, Fiber Optic Faceplates and Fiber Optic Tapers, that are historically constructed by combining a plurality of discrete optical fibers. Optical fibers are typically cylindrical strands of glass or optical polymer with an index of refraction of n 1 , sheathed or clad with a thin layer of a second glass or polymer with an index of refraction of n 2 , where n 2 is less than n 1 , thereby enabling the well-known phenomenon of Total Internal Reflection.
[0004] Fiber Optic Taper and Fiber Optic Faceplates are currently and typically constructed as follows:
1. A usually large number of discrete optical fibers are gathered into a bundle (usually round) and heated to the softening point of the cladding material while circumferential pressure is applied to the bundle, causing the fibers to fuse together.
a. In the case of a fiber optic faceplate, the fused bundle is then sliced into disks of desired thickness.
i. The faces of the disks are ground and polished and the faceplate is trimmed to the desired final size and shape.
b. In the case of a fiber optic taper, the bundle is heated to the softening point of the material and the bundle is longitudinally stretched so that the diameter necks down between the ends.
i. The tapered shape is then sliced at the neck and the ends, creating two fiber optic tapers.
c. As with the fiber optic faceplate, the ends are then ground and polished.
[0011] Thus it is seen that the current process requires potentially expensive and complex equipment to handle large bundles of thin, fragile fibers, provide controlled high-temperature compression and drawing, and perform slicing operations.
[0012] In view of this, it would be desirable to develop a method or methods of constructing or fabricating optical pathways as integral parts of a device structure, and that the optical pathways have equivalent optical properties to conventional optical fibers.
SUMMARY
[0013] The current Invention is a dramatic and innovative improvement to the methods of construction and fabrication of fiber optic devices in the current art.
[0014] In one aspect, the invention is a method of fabricating an optical fiber-like device by depositing curable optical materials of differing indices of refraction in a controlled manner forming integral optical pathways, the pathways exhibiting total internal reflection and functioning as optical fibers.
[0015] In many embodiments, depositing curable optical materials in a controlled manner includes depositing multiple layers of discrete deposits of first and second curable optical materials between a bottom surface or face and a top surface or face forming integral optical pathways of the first material surrounded by the second material, the second material having a lower index of refraction than the first material.
[0016] In many embodiments, depositing multiple layers of discrete deposits of first and second curable optical materials includes depositing the first and second materials on the corresponding first and second material deposits of the previous layer.
[0017] In many embodiments, depositing multiple layers of discrete deposits of first and second curable optical materials includes curing each layer of first and second materials prior to depositing a subsequent layer.
[0018] In many embodiments, curing each layer of first and second materials includes exposure to UV light.
[0019] In many embodiments, depositing multiple layers of discrete deposits of first and second curable optical materials includes depositing the first and second materials using first and second dispensing heads.
[0020] In many embodiments, the first and second dispensing heads are the same head.
[0021] In many embodiments, the first and second dispensing heads are computer controlled.
[0022] In many embodiments, the device is tapered between the bottom and top surfaces or faces by reducing each subsequent layer in area and material deposit size at a rate of taper desired.
[0023] In many embodiments, the first and second materials are selected from the group consisting of polymer resins, acrylics(methacrylate), polycarbonates, epoxies, polyesters and urethanes.
[0024] In another aspect, the invention is a method of fabricating an optical fiber-like device by depositing multiple layers of curable optical materials of differing indices of refraction in a controlled manner on a polished surface of a substrate by:
[0025] creating a first layer of curable optical materials on the substrate by:
depositing an array pattern of discrete deposits of a first curable liquid optical material on the substrate using one or more first dispensing heads; curing the first material; depositing a second curable liquid optical material all the areas surrounding the discrete deposits of the first material on the substrate using one or more second dispensing heads, the second material having a lower index of refraction than the first material; curing the second material;
[0030] creating subsequent layers of curable optical materials by:
depositing discrete deposits of a first curable liquid optical material on the discrete deposits of the previous layer using one or more first dispensing heads; curing the first material; depositing a second curable liquid optical material all the areas surrounding the discrete deposits of the first material using one or more second dispensing heads; curing the second material; and
[0035] repeating the creating subsequent layers of the first and second materials on the previous layer until a desired thickness of the fiber optic device is reached, the last layer creating a top surface or face and the layers of discrete deposits forming integral optical pathways of the first material surrounded by the second material between the substrate and top surface or face.
[0036] In many embodiments, curing the first and second materials include exposure of the first and second materials to UV light.
[0037] In many embodiments, the first and second materials are selected from the group consisting of polymer resins, acrylics(methacrylate), polycarbonates, epoxies, polyesters and urethanes.
[0038] In many embodiments, the device is tapered between the substrate and top surface or face by reducing each subsequent layer in area and material deposit size at a rate of taper desired.
[0039] In many embodiments, the top surface or face is polished.
[0040] In another aspect, the invention is a method of fabricating an optical fiber-like device by depositing multiple layers of curable optical materials of differing indices of refraction in a controlled manner on a polished surface of a substrate by:
[0041] creating an initial layer of curable optical material on the substrate by:
depositing an area of second material using one or more second dispensing heads that is equal to the size and shape of a cross-section of the desired optical fiber-like device, perpendicular to desired end faces of the device; curing the second material;
[0044] creating a first layer of curable optical materials on the substrate by:
depositing multiple lines or columns of a first curable liquid optical material on the substrate using one or more first dispensing heads; curing the first material; depositing a second curable liquid optical material all the areas surrounding the line or column of the first material on the substrate using one or more second dispensing heads, the second material having a lower index of refraction than the first material; curing the second material;
[0049] creating subsequent layers of curable optical materials by:
depositing multiple lines or columns a first curable liquid optical material on the previous layer using one or more first dispensing heads; curing the first material; depositing a second curable liquid optical material all the areas surrounding the lines or columns of the first material using one or more second dispensing heads; curing the second material; and
[0054] repeating the creating subsequent layers of the first and second materials on the previous layer until a desired final height of the fiber optic device is reached, the line or columns of first materials forming integral optical pathways of the first material surrounded by the second material between the end faces.
[0055] In many embodiments, curing the first and second materials include exposure of the first and second materials to UV light.
[0056] In many embodiments, the first and second materials are selected from the group consisting of polymer resins, acrylics(methacrylate), polycarbonates, epoxies, polyesters and urethanes.
[0057] In many embodiments, the device is tapered between the end faces by reducing the cross sectional area of each column of first material to reduce over its length from a large surface or face to a small surface or face.
[0058] In many embodiments, an initial construct is created upon the substrate using one or more second dispensing heads dispensing the second material in a size and shape of which corresponds to the size and shape of one outer surface of the desired taper in a chosen plane.
BRIEF DESCRIPTION OF THE DRAWINGS
[0059] FIGS. 1A-1H show one embodiment of fabricating a fiber optic faceplate.
[0060] FIGS. 2A-2H show another embodiment of fabricating a fiber optic faceplate.
[0061] FIGS. 3A-3J show one embodiment of fabricating a Fiber Optic Taper.
[0062] FIGS. 4A-4L show another embodiment of fabricating a Fiber Optic Taper.
DETAILED DESCRIPTION
[0063] Embodiments of the invention will now be described with reference to the figures, wherein like numerals reflect like elements throughout. The terminology used in the description presented herein is not intended to be interpreted in any limited or restrictive way, simply because it is being utilized in conjunction with detailed description of certain specific embodiments of the invention. Furthermore, embodiments of the invention may include several novel features, no single one of which is solely responsible for its desirable attributes or which is essential to practicing the invention described herein.
[0064] The disclosed invention is an innovative method of constructing or fabricating integral optical pathways of optical devices, in contrast to the prior art optical devices that are made up of a multiplicity of discrete optical fibers. The disclosed methods allow construction of optical pathways as integral parts of the optical devices. This allows construction or fabrication of optical devices with optical pathways having essentially equivalent optical properties to conventional optical fibers at a much lower cost.
[0065] While the invention is disclosed in relation to fiber optic faceplates and fiber optic tapers, it can readily be seen that the methods of construction or fabrication described herein are not limited to fiber optic faceplates and fiber optic tapers. Indeed, practically any device historically constructed using conventional optical fibers can be constructed more efficiently and more cost effectively using the methods of the disclosed invention. Additionally, using the methods of the disclosed invention, devices can now be constructed that would have been impossible or impractical using conventional optical fibers. An example of this is a device wherein a bend or curve is desired that is of too small of a radius for an optical fiber, but such limitation does not exist for a line or shape dispensed as a liquid and then cured.
[0066] A fiber optic faceplate is a coherent multi-fiber plate, which acts as a zero-depth window, transferring an image pixel by pixel (fiber by fiber) from one face of the plate to the other. Faceplates are often found in high-end imaging applications bonded to CCD's, voltage stand-off devices in electron microscopes and cathode ray tubes, and as substrates for phosphors. In some embodiments, the fiber optic faceplate can be as large as 355 mm (14″) square or as small as a few hundred microns across, with depth ranging from more than 100 mm down to 50-100 μm.
[0067] Fiber Optic Faceplate, Method 1
[0068] FIG. 1A shows one embodiment of a fiber optic faceplate 100 having a height H, width W and depth D. FIGS. 1B-1H show one embodiment of fabricating the fiber optic faceplate 100 . To create a fiber optic faceplate, a dispensing head is configured to dispense a curable liquid optical material of known index of refraction (“n 1 ”) upon a substrate 110 having a polished surface. A second dispensing head is configured to dispense a curable liquid optical material of a lower index of refraction (“n 2 ”) than the first material in all the areas surrounding the deposits of n 1 material. The dispensing heads are able to be controllably maneuvered in the x, y and z axes by well-known and conventional means, such as through the use of computer-controlled stepper motors, with dispensing rates similarly controllable. The curable liquid optical material may be any material that can be dispensed from a dispensing heads and cured, such as polymer resins, acrylics(methacrylate), polycarbonates, epoxies, polyesters and urethanes.
[0069] The process is described below.
[0070] 1. FIGS. 1B-1C show one or more first dispensing heads 105 dispensing upon a polished substrate surface of substrate 110 a pattern 115 (H×W) of discrete deposits of n 1 material 120 of the number and size(s) desired for the particular faceplate. The number, size and spacing of the deposits n 1 correspond to the number, size and spacing of optical fibers in an equivalent faceplate of traditional optical fiber construction. The deposits n 1 are then cured, such as by exposure to UV light 125 .
[0071] 2. FIGS. 1D-1E show one or more second dispensing heads 130 dispense n 2 material 135 in all the areas surrounding the deposits of n 1 material 120 , within the established perimeter of the face of the faceplate, dispensed by the first dispensing heads in step 1 . The n 2 material 135 is then cured, such as by exposure to UV light 125 . FIG. 1E shows one layer of n 1 material 120 and n 2 material 135 .
[0072] 3. The process now repeats, layering upon the previous layers, with the next layer of n 1 material deposits and n 2 material fill directly on top of the previous layer. FIG. 1F shows five layers of n 1 material 120 and n 2 material 135 .
[0073] 4. The process is repeated until the desired final thickness D of the faceplate is reached, shown in FIGS. 1G and 1H . The completed faceplate 100 is then removed from the substrate 110 . No polishing is needed on the surface or face 140 that was against the polished substrate surface of the substrate 110 . Little or no polishing is needed on the top surface or face 145 . No cutting of the outer size or shape (w or d) is necessary.
[0074] The result is an array of columns or integral optical pathways 150 of n 1 material surrounded by columns 155 of n 2 material. The integral optical pathways or ‘columns’ of n 1 material act the same as ‘fibers’ do in a conventional fiber optic faceplate. The columns 150 are in fact integrally-created fibers now ‘clad’ in n 2 material. The faceplate is simply ‘printed’ as described and is ready to use.
[0075] It can readily be seen that the method described herein is not restricted to square or rectangular face shapes. Fiber optic faceplates of practically any face shape, including circular, elliptical, rectangular and square, can be created.
[0076] Fiber Optic Faceplate, Method 2
[0077] FIG. 2A shows another embodiment of a fiber optic faceplate 200 having a height H, width W and depth D. FIGS. 2B-2H show one embodiment of fabricating the fiber optic faceplate 200 . To create a fiber optic faceplate, one or more dispensing heads are configured to dispense curable liquid optical materials, such as a polymer resins, acrylics(methacrylate), polycarbonates, epoxies, polyesters and urethanes, upon a substrate having a polished surface. A first dispensing head 205 is configured to dispense a first curable liquid optical material of known index of refraction (“n 1 ”) upon the polished surface and a second dispensing head 230 is configured to dispense a second curable liquid optical material, such as a polymer resins, acrylics(methacrylate), polycarbonates, epoxies, polyesters and urethanes, having a lower index of refraction (“n 2 ”) than the first material in all the areas surrounding the deposits of n 1 material. The dispensing heads are able to be controllably maneuvered in the x, y and z axes by well-known and conventional means, such as through the use of computer-controlled stepper motors, with dispensing rates similarly controllable.
[0078] The process is described below.
1. FIG. 2B shows one or more second dispensing heads 230 dispensing an initial thin layer of n 2 material 235 upon the polished substrate 210 , covering an area 215 (D×W) that is equal to the size and shape of the cross-section, perpendicular to the faces, of the desired faceplate. This layer is then cured, such as by exposure to UV light 225 . 2. FIGS. 2C-2D show one or more first dispensing heads 205 dispensing a line or column 250 of n 1 material 220 upon the cured layer of n 2 material 235 , perpendicular to the long dimension of the faceplate cross-section, and of a width and at a spacing equal to the width and spacing of the fibers in a conventional faceplate of the same size. This material is then cured, such as by exposure to UV light 225 . FIG. 2D shows one layer of n 1 material 220 upon the n 2 material 235 . 3. More n 2 material 235 is then dispensed between and over the n 1 material 220 lines created in step 2 . This material is then cured. 4. The process now repeats, layering upon the previous layers. FIGS. 2E and 2F show four layers of n 1 material 220 and n 2 material 235 . 5. The process is repeated until the desired final height h of the faceplate is reached, shown in FIGS. 2G and 2H . 6. A thin layer of n 2 material 235 is dispensed as the final layer and cured. 7. The completed faceplate 200 is then removed from the substrate 210 . Depending upon the application and level of optical quality desired, the faces 240 , 245 of the completed faceplate may be optimized by grinding or sanding, and polishing.
[0086] The result is an array of columns or integral optical pathways 250 of n 1 material surrounded by columns 255 of n 2 material. The integral optical pathways or ‘columns’ act as the ‘fibers’ do in a conventional fiber optic faceplate. The columns are in fact integrally-created fibers now ‘clad’ in n 2 material. The faceplate is simply ‘printed’ as described and is ready to use.
[0087] It can readily be seen that the method described herein is not restricted to square or rectangular face shapes. Fiber optic faceplates of practically any face shape, including circular, elliptical, rectangular and square, can be created.
[0088] Fiber Optic Taper, Method 1
[0089] FIGS. 3A-3J show one embodiment of fabricating a Fiber Optic Taper 300 that offers a low-distortion method of magnifying or reducing an image for image transfer applications. The Fiber Optic Taper 300 has a shape with a large end and small end that transmits the image from its input surface or face to its output surface or face, shown in FIGS. 3A-3C . To create a Fiber Optic Taper, one or more dispensing heads are configured to dispense curable liquid optical materials, such as polymer resins, acrylics(methacrylate), polycarbonates, epoxies, polyesters and urethanes, upon a substrate 310 having a polished surface. A first dispensing head 305 is configured to dispense a first curable liquid optical material of known index of refraction (“n 1 ”) upon the polished surface and a second dispensing head 330 is configured to dispense a second curable liquid optical material, such as a polymer resins, acrylics(methacrylate), polycarbonates, epoxies, polyesters and urethanes, having a lower index of refraction (“n 2 ”) than the first material in all the areas surrounding the deposits of n 1 material. The dispensing heads are able to be controllably maneuvered in the x, y and z axes by well-known and conventional means, such as through the use of computer-controlled stepper motors, with dispensing rates similarly controllable.
[0090] The fiber optic taper 300 is created using the dispensing arrangement previously described above, as follows:
1. FIGS. 3D and 3E show one or more first dispensing heads 305 dispensing upon a polished substrate surface of substrate 310 a pattern 315 (H×W) of discrete deposits of n 1 material 320 of the number and size(s) desired for the particular faceplate. The number, size and spacing of the deposits n 1 correspond to the number, size and spacing of optical fibers in an equivalent taper of traditional optical fiber construction. The deposits n 1 are then cured, such as by exposure to UV light 325 . 2. FIGS. 3F and 3G show one or more second dispensing heads 330 dispense n 2 material 335 in all the areas surrounding the deposits of n 1 material 320 , within the established perimeter of the face of the taper, dispensed by the first dispensing heads in step 1 . The n 2 material 335 is then cured, such as by exposure to UV light 325 . FIG. 3G shows one layer of n 1 material 320 and n 2 material 335 . 3. The process now repeats, layering upon the previous layers, with the next layer of n 1 material deposits and n 2 material fill directly on top of the previous layer. Each subsequent layer reducing in area and deposit size at the rate of taper desired. FIGS. 3H and 3I show four layers of n 1 material 320 and n 2 material 335 with the taper exaggerated for illustration. 4. The process is repeated until the desired final thickness D and taper is reached, shown in FIG. 3J . The completed Fiber Optic Taper 300 is then removed from the substrate 310 . No polishing is needed on the surface or face 340 that was against the polished substrate surface of the substrate 310 . Little or no polishing is needed on the top surface or face 345 . No other cutting, finishing or machining operations are necessary.
[0095] The result is an array of tapered columns 350 of n 1 material surrounded by columns 355 of n 2 material. The ‘columns’ act as the ‘fibers’ do in a conventional fiber optics. The columns are in fact integrally-created fibers now ‘clad’ in n 2 material. The faceplate is simply ‘printed’ as described and is ready to use.
[0096] It can readily be seen that the method described herein is not restricted to square or rectangular face shapes. Fiber optic tapers of practically any face shape, including circular, elliptical, rectangular and square, can be created. Furthermore, this method allows the large face and small face to be of different shapes or aspect ratios, enabling fiber optic tapering functions such as anamorphic squeeze or other intentional geometric manipulation of the image.
[0097] Fiber Optic Taper, Method 2
[0098] FIGS. 4A-4L show another embodiment of fabricating a Fiber Optic Taper 400 , similar to Fiber Optic Taper 300 , except in this method the fiber optic taper is created in cross-section, that is, in layers that are primarily perpendicular to the faces of the Taper. The layers can therefore be primarily oriented in the X-Z plane ( FIG. 4D ) or the Y-Z ( FIG. 4E ), whichever is deemed to be advantageous to the particular faceplate being fabricated.
[0099] The method is as follows:
1. An initial construct is created upon a polished substrate using one or more second dispensing heads 430 dispensing an initial layer of n 2 material 435 , the size and shape 415 of which corresponds to the size and shape of one outer surface of the desired Taper in the chosen plane ( FIGS. 4D and 4E ). This construct is then cured, such as by exposure to UV light 425 . 2. FIGS. 4F-4H show one or more first dispensing heads 405 dispensing continuous ‘strings’ or columns 450 from the large face to the small face of n 1 material 420 upon the cured layer of n 2 material 435 . The dispensing rate or speed of dispensing is controlled as each string is dispensed, so that the cross sectional area of each string is made to reduce over its length from the large face to the small face, corresponding to the taper of the fibers in a conventional fiber optic taper. This material is then cured, such as by exposure to UV light 425 . 3. More n 2 material 435 is then dispensed between and over the n 1 material 420 ‘strings’ created in step 2 forming columns 455 . This material is then cured, such as by exposure to UV light 425 . FIG. 4H shows one layer of n 1 material 420 and n 2 material 435 upon the initial n 2 material 435 in step 1 . 4. The process now repeats, with each layer comprising a set of strings of n 1 material 420 , cured, followed by a layer of n 2 fill 435 , cured. FIGS. 4I and 4J show the large end 440 and small end 445 views of four layers of n 1 material 420 and n 2 material 435 . 5. The process continues until the Taper is complete and thin layer of n 2 material 235 is dispensed as the final layer and cured, shown in FIGS. 4K and 4L . 6. The completed taper 400 is then removed from the substrate 410 . Depending upon the application and level of optical quality desired, the faces 440 , 445 of the completed taper may be optimized by grinding or sanding, and polishing.
[0106] An advantage of Fiber Optic Taper Method #2 over Fiber Optic Taper Method #1 is that each “fiber” is created by a continuous extrusion of n 1 material so that there are no ‘step’ or layer imperfections in the ‘fibers’ that might be present in Method #1.
[0107] It can readily be seen that the method described herein is not restricted to square or rectangular face shapes. Fiber optic tapers of practically any face shape, including circular, elliptical, rectangular and square, can be created. Furthermore, this method allows the large face and small face to be of different shapes or aspect ratios, enabling fiber optic tapering functions such as anamorphic squeeze or other intentional geometric manipulation of the image.
[0108] Other Fiber Optic Devices
[0109] It can readily be seen that the methods of the Invention are not limited to construction of fiber optic faceplates and fiber optic tapers. Indeed, practically any device historically constructed using conventional optical fibers can be constructed more efficiently and more cost effectively using the methods of the Invention.
[0110] Additionally, using the methods of the Invention, devices can now be constructed that would have been impossible or impractical using conventional optical fibers. An example of this is a device wherein a bend or curve is desired that is of too small of a radius for an optical fiber, but such limitation does not exist for a line or shape dispensed as a liquid and then cured.
[0111] Thus the limitations and shortcomings of the methods of producing the devices in the current art are overcome in the current invention, which provides significant novel improvements, including improvements in range of applications, versatility, manufacturability and cost-effectiveness.
[0112] It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims. In addition, where this application has listed the steps of a method or procedure in a specific order, it may be possible, or even expedient in certain circumstances, to change the order in which some steps are performed, and it is intended that the particular steps of the method or procedure claims set forth herebelow not be construed as being order-specific unless such order specificity is expressly stated in the claim. | Disclosed are devices, systems, and methods for construction or fabrication of optical fiber-like devices by depositing curable optical materials of differing indices of refraction in a controlled manner forming integral optical pathways, the integral optical pathways exhibiting total internal reflection and functioning essentially equivalent optical properties to conventional optical fibers optical pathways. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation Application of U.S. application Ser. No. 12/585,172 filed on Sep. 8, 2009, which is a continuation of U.S. application Ser. No. 11/498,158 filed on Aug. 3, 2006. The present application claims priority from U.S. application Ser. No. 12/585,172 filed on Sep. 8, 2009, which claims priority from U.S. application Ser. No. 11/498,158 filed on Aug. 3, 2006, which claims priority from Japanese Patent Application No. 2005-278161 filed on Sep. 26, 2005, the content of which is hereby incorporated by reference into this application.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a liquid crystal display device, and more particularly to a lateral-electric-field-type liquid crystal display device which can enhance a display numerical aperture.
[0003] As a display device for various kinds of personal digital assistants and television receiver sets, a display device which uses a so-called flat-type display panel as represented by a liquid crystal display device has been a mainstream. Further, as the liquid crystal display device, an active-method-type liquid crystal display device has been popularly used. The active-method-type liquid crystal display device generally uses a thin film transistor as a drive element of a pixel and hence, hereinafter, the display device which adopts the thin film transistor as the drive element is explained as an example. As one type of such a liquid crystal display device, there has been known a lateral-electric-field-type liquid crystal display device which is referred to IPS (in-plane-switching) type display device.
[0004] FIG. 9 is a plan view for explaining an example of the base pixel structure of the thin film transistor of the IPS type liquid crystal display device. Further, FIG. 10 is a cross-sectional view of the display device which also includes a color filter substrate taken along a line D-D′ in FIG. 9 . The planer constitution of the pixel of the IPS type liquid crystal display device is, as shown in FIG. 9 , formed in the inside of a region which is surrounded by two gate lines GL and two data lines DL. A thin film transistor TFT is formed on a portion of the region (pixel region). The thin film transistor TFT has a drain (or a source) electrode SD 2 thereof connected to the data line DL, has a gate electrode GT thereof connected to the gate line GL, and has a source (drain) electrode SD 1 connected to a pixel electrode PX through a contact hole CH. Here, although the drain electrode and the source electrode are exchanged from each other during an operation, the explanation is made hereinafter with respect to a case in which the thin film transistor TFT includes the source electrode SD 1 and the drain electrode SD 2 .
[0005] As shown in FIG. 10 , the cross-sectional structure of the pixel forms the thin film transistor TFT which is constituted of a semiconductor layer (silicon semiconductor) SI, a second insulation film INS 2 , the gate electrode GT, a third insulation film INS 3 , the source electrode SD 1 and the drain electrode SD 2 on a first insulation film INS 1 which is formed on a main surface of one substrate (a thin film transistor substrate, hereinafter, a TFT substrate) SUB 1 which is preferably made of glass. Here, the scanning lines GL shown in FIG. 9 are formed on the same layer as the gate electrodes GT, the data lines DL are formed on the third insulation film INS 3 , and the source electrodes SD 1 and the drain electrodes SD 2 are formed on the same layer as the data lines DL. The source electrodes SD 1 and the drain electrodes SD 2 are connected to the semiconductor layers SI via the contact holes which are formed in the second insulation film INS 2 at the time of forming the source electrodes SD 1 , drain electrodes SD 2 as films.
[0006] A fourth insulation film INS 4 which constitutes a protective film (passivation film) is formed in a state that the fourth insulation film INS 4 covers the source electrode SD 1 , the drain electrode SD 2 and the data lines DL. Here, a counter electrode CT is formed in a spreading manner on the fourth insulation film INS 4 in a state that a contact electrode CT covers a most portion of the pixel region, and a contact hole CH which reaches the source electrode SD 1 is formed in the fourth insulation film INS 4 . Further, a fifth insulation film INS 5 is formed in a state that the fifth insulation film INS 5 covers the counter electrode CT.
[0007] The pixel electrode PX is formed on the fifth insulation film INS 5 in a comb-teeth shape, and one end of the pixel electrode PX is connected to the source electrode SD 1 via the contact hole CH. Then, an orientation film ORI 1 is formed in a state that the orientation film covers a topmost surface of the pixel electrode PX.
[0008] On a main surface of another substrate (color filter substrate, hereinafter, referred to as a CF substrate) SUB 2 which is preferably made of glass, color filters CF which are defined from each other by a black matrix BM are formed, and an orientation film ORI 2 is formed on a topmost surface of the substrate SUB 2 . The current display devices mostly adopt a full color display. In this full color display, basically, unit pixels (sub pixels) of three colors consisting of red (R), green (G), and blue (B) constitute one color pixel.
[0009] In the IPS type liquid crystal display device, a liquid crystal LC is sealed in the inside of a space between the orientation film ORI 1 of the TFT substrate SUB 1 and the orientation film ORI 2 of the CF substrate SUB 2 . The liquid crystal LC which is driven by the thin film transistor TFT is rotated by a component of an electrical field E parallel to a surface of the substrate which is generated between the pixel electrode PX and the counter electrode CT in the inside of the surface in which the orientation direction of the liquid crystal LC is parallel to the surface of the substrate and hence, the lighting and non-lighting of the pixel can be controlled. As a document which discloses such an IPS-type liquid crystal display device, International Publication WO 01/018597 can be named.
SUMMARY OF THE INVENTION
[0010] In an IPS-type liquid crystal display device, as shown in FIG. 10 , a portion of a contact hole CH which connects a pixel electrode to a source electrode constituting an output electrode of the thin film transistor is not used as a display region together with a portion on which the thin film transistor is arranged. Also a black matrix which is mounted on a CF substrate is formed in a state that the black matrix covers the thin film transistor and the contact hole portion. Accordingly, the increase of an effective area of the pixel, that is, the enhancement of a numerical aperture is limited.
[0011] It is an object of the present invention to provide a lateral-electric-field-type liquid crystal display device which can enhance a numerical aperture of pixels thus realizing a bright image display.
[0012] Typical constitutions of the present invention are described hereinafter.
[0013] (1) A liquid crystal display device which includes a first substrate having pixel electrodes, counter electrodes and thin film transistors, a second substrate which faces the first substrate in an opposed manner, and a liquid crystal layer between the first substrate and the second substrate, wherein
[0014] at least a portion of the pixel electrode is overlapped to the thin film transistor via a first insulation film, the pixel electrode is connected to an output electrode of the thin film transistor via a contact hole which is formed in the first insulation film, and
[0015] the counter electrode is arranged above the pixel electrode by way of a second insulation film in a state that the counter electrode is overlapped to the pixel electrode, the counter electrode is formed at a position avoiding the contact hole formed in the first insulation film as viewed in a plan view, and at least a portion of the counter electrode is overlapped to the thin film transistor.
[0016] (2) In the constitution (1), a region where the contact hole is formed is a reflective display region.
[0017] (3) In the constitution (1) or (2), at least a portion of the region of the thin film transistor constitutes a reflective display region.
[0018] (4) In the constitution (1), the liquid crystal display device includes a reflective display region.
[0019] (5) In any one of the constitutions (1) to (4), the liquid crystal display device includes a reflective display region and a transmissive display region.
[0020] (6) In any one of the constitutions (1) to (5), an input electrode and the output electrode of the thin film transistor are formed of a reflective conductive film.
[0021] (7) In any one of the constitutions (1) to (6), the pixel electrode is formed of a transparent conductive film.
[0022] (8) In any one of the constitutions (1) to (6), at least a portion of the pixel electrode is formed of a reflective conductive film.
[0023] (9) In any one of the constitutions (1) to (4), the pixel electrode, the input electrode and the output electrode of the thin film transistor are formed of a reflective conductive film.
[0024] (10) In any one of the constitutions (1) to (9), a portion of the second insulation film is filled in the contact hole, and the second insulation film in the region overlapped to the contact hole has a liquid-crystal-layer-side surface thereof leveled.
[0025] (11) In any one of the constitutions (1) to (9), an insulation member which is made of a material different from a material of the second insulation film is filled in the contact hole, and the second insulation film in the region overlapped to the contact hole has a liquid-crystal-layer-side surface thereof leveled.
[0026] It is needless to say that the present invention is not limited to the constitutions which are described above and the constitutions which will be explained in conjunction with embodiments described later and various modifications are conceivable without departing from the technical concept of the present invention.
[0027] According to the constitution of the present invention, the thin film transistor and the contact hole portion which connects an output electrode of the TFT to the pixel electrode which have been considered as portions which do not contribute to a display in the pixel region can be used as the reflective display region and hence, is possible to enhance a numerical aperture and to increase a display brightness. Further, conventionally, thicknesses of the electrode and the insulation film which have been formed on the contact hole portion are reduced compared to thicknesses of the electrode and the insulation film which have been formed on a leveled surface portion and hence, there exists a possibility that short-circuiting occurs between the counter electrode and the pixel electrode which are formed on the contact hole portion. According to the present invention which eliminates the mounting of the counter electrode on the contact hole portion, it is possible to avoid the occurrence of the above-mentioned short-circuiting.
[0028] Further, according to the present invention, since the surface of the insulation film can be leveled by embedding the insulation member in the opening formed in the insulation film which is formed on the contact hole portion, the orientation film which is formed over the insulation film can be leveled. Accordingly, it is also possible to impart the accurate orientation to the liquid crystal on the contact hole portion in the same manner as other portions thus eliminating a display defect such as a light leakage or the like attributed to the defective orientation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1 is a plan view which shows an example of the constitution of one pixel for explaining an embodiment 1 of a liquid crystal display device according to the present invention;
[0030] FIG. 2 is a cross-sectional view taken along a line A-A′ in FIG. 1 ;
[0031] FIG. 3 is a plan view which shows an example of the constitution of one pixel for explaining an embodiment 2 of a liquid crystal display device according to the present invention;
[0032] FIG. 4 is a cross-sectional view taken along a line B-B′ in FIG. 3 ;
[0033] FIG. 5 is a plan view which shows an example of the constitution of one pixel for explaining an embodiment 3 of a liquid crystal display device according to the present invention;
[0034] FIG. 6 is a cross-sectional view taken along a line C-C′ in FIG. 5 ;
[0035] FIG. 7 is an explanatory view of a transmissive brightness-voltage characteristic due to a dielectric constant of a fifth insulation film for explaining an embodiment 3;
[0036] FIG. 8 is an explanatory view of a transmissive brightness-voltage characteristic due to a film thickness of the fifth insulation film for explaining the embodiment 3;
[0037] FIG. 9 is a plan view which explains one example of the basic pixel structure of a thin film transistor-substrate-side of an ISP-type liquid crystal display device; and
[0038] FIG. 10 is a cross-sectional view of the liquid crystal display device which also includes a color filter substrate taken along a line D-D′ in FIG. 9 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0039] Hereinafter, embodiments of the present invention are explained in detail in conjunction with drawings of embodiments.
Embodiment 1
[0040] FIG. 1 is a plan view which shows an example of the constitution of one pixel for explaining an embodiment 1 of a liquid crystal display device according to the present invention. Further, FIG. 2 is a cross-sectional view taken along a line A-A′ in FIG. 1 . This liquid crystal display device is of an IPS type. In the same manner as the display device shown in FIG. 10 , a pixel region is formed in a region which is surrounded by two scanning lines (hereinafter, also referred to as gate lines) GL and two image signal lines (hereinafter, also referred to as data lines) DL. A thin film transistor TFT which constitutes an active element is formed in a portion of the pixel region. The thin film transistor TFT has a drain (or a source) electrode SD 2 thereof connected to the data line DL, has a gate electrode GT thereof connected to the gate line GL and has a source (a drain) electrode SD 1 thereof connected to a pixel electrode PX via a contact hole CH.
[0041] As shown in FIG. 2 which is a cross-sectional view taken along a line A-A′ in FIG. 1 , the cross-sectional structure of the pixel includes the thin film transistor TFT which is constituted of a semiconductor layer (silicon semiconductor) SI, a second insulation film INS 2 , the gate electrode GT, a third insulation film INS 3 , the source electrode SD 1 and the drain electrode SD 2 on a first insulation film INS 1 which is formed on a main surface of one substrate (thin film transistor substrate, hereinafter, also referred to as a TFT substrate) SUB 1 which is preferably made of glass. Here, the gate lines GL shown in FIG. 1 are formed on the same layer as the gate electrodes GT, the data lines DL are formed on the third insulation film INS 3 , and the source electrodes SD 1 and the drain electrodes SD 2 are formed on the same layer as the data lines DL. The source electrode SD 1 and the drain electrode SD 2 are connected to the semiconductor layer SI via contact holes which are formed in the second insulation film INS 2 at the time of forming these electrodes.
[0042] A fourth insulation film INS 4 which constitutes a protective film (passivation film) is formed in a state that the fourth insulation film INS 4 covers the source electrode SD 1 , the drain electrode SD 2 and the data lines DL. Here, a pixel electrode PX is formed in a spreading manner on the fourth insulation film INS 4 in a state that the pixel electrode PX covers a most portion of the pixel region including a portion above the thin film transistor TFT. A contact hole CH which reaches the source electrode SD 1 is formed in the fourth insulation film INS 4 . Further, a fifth insulation film INS 5 is formed on the fourth insulation film INS 4 in a state that the fifth insulation film INS 5 covers the pixel electrode PX. A counter electrode CT is formed on the fifth insulation film INS 5 in a comb-teeth shape. Here, symbol PE indicates cutout portions of the counter electrode CT and the pixel electrode which is exposed from the cutout portions are viewed. Further, an orientation film ORI 1 is formed to cover a topmost surface of the counter electrode CT.
[0043] On the main surface of another substrate (color filter substrate, hereinafter, referred to as a CF substrate) SUB 2 which is preferably made of glass, the color filters CF which are defined from each other by a black matrix BM are formed, and an orientation film ORI 2 is formed on a topmost surface of the substrate SUB 2 . The currently available display devices mostly adopt a full color display. In the full color display (hereinafter, also simply referred to as a color display), basically, unit pixels (sub pixels) of three colors consisting of red (R), green (G), and blue (B) constitute one color pixel.
[0044] In the IPS-type liquid crystal display device, liquid crystal LC is sealed in the inside of a space between the orientation film ORI 1 of the TFT substrate SUB 1 and the orientation film ORI 2 of the CF substrate SUB 2 . With respect to the liquid crystal LC which is driven by the thin film transistor TFT, the orientation direction of the liquid crystal LC is rotated by a component parallel to a surface of the substrate of an electrical field E which is generated between the pixel electrode PX and the counter electrode CT in a plane parallel to the substrate surface thus controlling the lighting and non-lighting of the pixel.
[0045] Here, the manufacturing process of the liquid crystal display device of the embodiment 1 is explained. On an insulation substrate which is preferably made of glass, a semiconductor island is formed by forming an a-Si or p-Si semiconductor film by patterning. Since a process for forming the insulation films and the gate electrodes and a process for forming the source electrodes SD 1 and the drain electrodes SD 2 on the semiconductor island are already known, the explanation of these processes is omitted. In the embodiment 1, the source electrode SD 1 and the drain electrode SD 2 of the thin film transistor TFT are formed of a stacked film of MoW/AlSi/MoW.
[0046] After forming the source electrode SD 1 and the drain electrode SD 2 , a fourth insulation film is formed over the source electrode SD 1 and the drain electrode SD 2 . A forming method of the fourth insulation film is explained hereinafter. First of all, an organic resin which is formed of polymethyl silazane is applied to the substrate using a spin coating method. Using a photo mask which has a desired pattern, the exposure is performed by radiating i rays to the organic resin and, thereafter, the organic resin is humidified thus forming silanol. The silanol is developed by an alkali developer and is removed. Next, the full surface exposure is performed by radiating ghi rays to the substrate and, thereafter, the substrate is humidified again. Accordingly, the silanol is formed on a portion where the silanol is not removed by the above-mentioned developing. Polymethyl siloxane is formed on the desired portion by baking the silanol thus forming the fourth insulation film.
[0047] A contact hole which connects the source electrode of the thin film transistor TFT and the pixel electrode described later to each other is formed by removing the insulation film 4 by patterning. A thickness of the insulation film 4 is set to 1 μm.
[0048] With respect to the pixel electrode PX, an ITO film which is a transparent conductor film is formed with a thickness of 77 nm by sputtering, and a photosensitive resist is applied to the ITO film. The exposure is performed using a photo mask which has a desired pattern, and the photosensitive resist is partially removed using an alkali developer (the exposed portion being removed when a positive-type photosensitive resist is used). Using the pattern of the photosensitive resist as a mask, the transparent conductor film is removed by an ITO etchant (for example, oxalic acid).
[0049] Then, the photosensitive resist is removed using a resist peeling liquid (for example, monoethanolamine:MEA). The pattern of the formed pixel electrode PX has a rectangular shape, and is formed on the substantially whole surface of the region which is surrounded by the image signal lines and the scanning signal lines.
[0050] On the ITO film which constitutes the pixel electrode PX, a fifth insulation film INS 5 which is made of SiN (dielectric constant: 6.7) is formed using a CVD method. In this embodiment, a thickness of the fifth insulation film is set to 300 nm. Here, although the patterning of the fifth insulation film is substantially equal to the patterning adopted by a method for forming the pixel electrode, the SiN film is etched by dry etching using a SF 6 +O 2 gas or a CF 4 gas.
[0051] The comb-teeth-shaped counter electrode CT is formed in the same process as the pixel electrode PX. The counter electrode CT is formed by avoiding a portion above the contact hole which connects the pixel electrode PX and the source electrode of the thin film transistor TFT to each other.
[0052] Next, a driving method of the liquid crystal display device of the embodiment 1 is explained. An image signal is supplied to the pixel electrode PX via the thin film transistor TFT. A constant voltage is applied to the counter electrode CT or an AC voltage (AC driving) is applied to the counter electrode at the timing of supplying scanning signals. When such a voltage is applied, between the pixel electrode PX and the edge of the comb-teeth shaped counter electrode CT, a so-called fringe electric field E is generated (see, FIG. 1 ). Further, the molecular orientation of the liquid crystal LC is controlled by the fringe electric field E.
[0053] In the embodiment 1, since the counter electrode CT is not arranged above the contact hole for connecting the pixel electrode PX to the source electrode of the thin film transistor TFT, the liquid crystal molecules which exist above the contact hole have the orientation thereof also controlled by the fringe electric field E and contribute to a display. That is, by forming the source electrode SD 1 and the drain electrode SD 2 using a reflective conductive film, an upper region of the thin film transistor TFT which includes the contact hole CH portion also forms a reflective display region, while forming the pixel electrode PX in the pixel region other than the thin film transistor TFT as the transparent conductive film such as the ITO film, it is possible to constitute a reflective/transmissive liquid crystal display device which can enhance an numerical aperture thereof. Further, even when a portion of the pixel electrode PX is formed of the reflective conductive film, it is possible to constitute the reflective/transmissive liquid crystal display device.
[0054] Further, by forming a reflective metal film on the ITO film which constitutes the pixel electrode PX or by forming the whole pixel electrode PX per se using a reflective conductive film in the same manner as the source electrode SD 1 and the drain electrode SD 2 , it is possible to constitute a reflective liquid crystal display device.
[0055] Still further, by adopting the constitution described in the embodiment 1, even when the insulation film at the contact hole CH portion has a small thickness, the counter electrode CT is not arranged on the portion and hence, the occurrence of the short-circuiting of the pixel electrode PX and the counter electrode CT is prevented whereby a yield rate is enhanced thus enabling the acquisition of a highly reliable liquid crystal display device.
Embodiment 2
[0056] FIG. 3 is a plan view which shows an example of the constitution of one pixel for explaining an embodiment 2 of a liquid crystal display device according to the present invention, while FIG. 4 is a cross-sectional view taken along a line B-B′ in FIG. 3 . The liquid crystal display device of the embodiment 2 is also of an IPS type. In the same manner as the embodiment 1, a pixel region is formed in the inside of a region which is surrounded by two gate lines GL and two data lines DL. A thin film transistor TFT is formed at a portion of the pixel region. The thin film transistor TFT has a drain (or a source) electrode SD 2 thereof connected to the data line DL, has a gate electrode GT thereof connected to the gate line GL, and has a source (a drain) electrode SD 1 thereof connected to a pixel electrode PX via a contact hole CH.
[0057] As shown in FIG. 4 which is a cross-sectional view taken along a line B-B′ in FIG. 3 , the cross-sectional structure of the pixel includes the thin film transistor TFT which is constituted of a semiconductor layer SI, a second insulation film INS 2 , the gate electrode GT, a third insulation film INS 3 , the source electrode SD 1 and the drain electrode SD 2 on a first insulation film INS 1 which is formed on a main surface of a TFT substrate SUB 1 . Here, the gate lines GL shown in FIG. 3 are formed on the same layer as the gate electrodes GT, the data lines DL are formed on the third insulation film INS 3 , and the source electrodes SD 1 and the drain electrodes SD 2 are formed on the same layer as the data lines DL. The source electrode SD 1 and the drain electrode SD 2 are connected to the semiconductor layer SI via contact holes which are formed in the second insulation film INS 2 at the time of forming these electrodes.
[0058] A fourth insulation film INS 4 is formed in a state that the fourth insulation film INS 4 covers the source electrode SD 1 , the drain electrode SD 2 and the data lines DL. Here, a pixel electrode PX is formed in a spreading manner on the fourth insulation film INS 4 in a state that the pixel electrode PX covers a most portion of the pixel region including a portion above the thin film transistor TFT. A contact hole CH which reaches the source electrode SD 1 is formed in the fourth insulation film INS 4 . Further, a fifth insulation film INS 5 is formed in a state that the fifth insulation film INS 5 covers the pixel electrode PX. The fifth insulation film INS 5 is filled in the inside of the contact hole CH, and a surface of the fifth insulation film INS 5 including an upper portion of the contact hole CH is leveled. On the leveled fifth insulation film INS 5 , a counter electrode CT is formed in a comb-teeth shape. Here, symbol PE indicates cutout portions of the counter electrode CT, and the pixel electrode which is exposed from the cutout portions are viewed. Further, an orientation film ORI 1 is formed to cover a topmost surface of the counter electrode CT.
[0059] On a main surface of a CF substrate SUB 2 , color filters CF which are defined from each other by a black matrix BM are formed in the same manner as the embodiment 1, and an orientation film ORI 2 is formed on a topmost surface of the CF substrate SUB 2 . Each color filter CF is basically constituted of unit pixels (sub pixels) of three colors consisting of red (R), green (G), and blue (B), and a color one pixel (pixel) is constituted of the three colors of the unit pixels.
[0060] Liquid crystal LC is sealed in the inside of a space between the orientation film ORI 1 of the TFT substrate SUB 1 and the orientation film ORI 2 of the CF substrate SUB 2 . With respect to the liquid crystal LC which is driven by the thin film transistor TFT, the orientation direction of the liquid crystal is rotated by a component parallel to a surface of the substrate of an electrical field E which is generated between the pixel electrode PX and the counter electrode CT in a plane parallel to the substrate surface thus controlling the lighting and non-lighting of the pixel.
[0061] The manufacturing process of the liquid crystal display device of the embodiment 2 is explained hereinafter by focusing on points which make this embodiment 2 different from the embodiment 1. With respect to the process up to the formation of the pixel electrode PX in which the source electrode SD 1 and the drain electrode SD 2 are formed, the fourth insulation film is formed over the source electrode SD 1 and the drain electrode SD 2 and, thereafter, the pixel electrodes PX are formed, such a process is substantially equal to the process of the embodiment 1. Thereafter, a photosensitive resist (for example, JSR-made PC-452) is applied to an ITO film which forms the pixel electrodes PX. The photosensitive resist is exposed using a photo mask which has a desired pattern, the photosensitive resist is partially removed using an alkali developer, and the stacked structure is baked. Although irregularities of a surface can be controlled based on baking conditions of this baking, in this embodiment, a baking temperature is set to 230° C. and a baking period is set to 60 minutes so as to substantially level a surface of the fifth insulation film INS 5 . Further, the fifth insulation film INS 5 assumes a film thickness of 300 nm at a surface leveled portion (other than the contact hole portion) of the pixel electrodes after baking.
[0062] Although a forming process of the counter electrode CT of the embodiment 2 is equal to the forming process of the counter electrode CT of the embodiment 1, in the embodiment 2, the formation of the counter electrode CT above the contact hole CH is not excluded.
[0063] Next, a driving method of the liquid crystal display device of the embodiment 2 is explained hereinafter by focusing on points which make this embodiment 2 different from the embodiment 1. In the embodiment 1, rubbing treatment of the orientation film may not be sufficiently performed depending on the degree of irregularities of a portion on which the contact hole CH is formed and hence, a liquid crystal orientation regulating force (an anchoring strength) may become small thus easily generating an image retention. The image retention is a phenomenon in which liquid crystal which is driven by an electric field does not return to an initial state even after the electric field is eliminated. However, according to the constitution of the embodiment 2, the surface of the fifth insulation film INS 5 which is formed above a portion in which the contact hole CH is formed is leveled and hence, the rubbing treatment can be performed sufficiently whereby the generation of the image retention can be suppressed.
Embodiment 3
[0064] FIG. 5 is a plan view which shows an example of the structure of one pixel for explaining an embodiment 3 of the liquid crystal display device according to the present invention, while FIG. 6 is a cross-sectional view taken along a line C-C′ in FIG. 5 . The liquid crystal display device of the embodiment 3 is also of an IPS type. In the same manner as the embodiment 1 and the embodiment 2, a pixel region is formed in the inside of a region which is surrounded by two gate lines GL and two data lines DL. A thin film transistor TFT is formed at a portion of the pixel region. The thin film transistor TFT has a drain (or a source) electrode SD 2 thereof connected to the data lines DL, has a gate electrode GT thereof connected to the gate lines GL and has a source (a drain) electrode SD 1 there of connected to a pixel electrode PX via a contact hole CH.
[0065] As shown in FIG. 6 which is a cross-sectional view taken along a line C-C′ in FIG. 5 , the cross-sectional structure of the pixel includes the thin film transistor TFT which is constituted of a semiconductor layer SI, a second insulation film INS 2 , the gate electrode GT, a third insulation film INS 3 , the source electrode SD 1 and the drain electrode SD 2 on a first insulation film INS 1 which is formed on a main surface of a TFT substrate SUB 1 . Here, the gate lines GL shown in FIG. 5 are formed on the same layer as the gate electrodes GT, the data lines DL are formed on the third insulation film INS 3 , and the source electrodes SD 1 and the drain electrodes SD 2 are formed on the same layer as the data lines DL. The source electrode SD 1 and the drain electrode SD 2 are connected to the semiconductor layer SI via contact holes which are formed in the second insulation film INS 2 at the time of forming these electrodes.
[0066] A fourth insulation film INS 4 is formed in a state that the fourth insulation film INS 4 covers the source electrode SD 1 , the drain electrode SD 2 and the data lines DL. Here, a pixel electrode PX is formed in a spreading manner on the fourth insulation film INS 4 in a state that the pixel electrode PX covers a most portion of the pixel region including a portion above the thin film transistor TFT. A contact hole CH which reaches the source electrode SD 1 is formed in the fourth insulation film INS 4 . A sixth insulation film INS 6 is filled in the inside of the contact hole CH, a fifth insulation film INS 5 is formed on the sixth insulation film INS 6 in a state that the fifth insulation film INS 5 covers the pixel electrode PX. A surface of the fifth insulation film INS 5 including an upper portion of the contact hole CH is leveled. On the leveled fifth insulation film INS 5 , a counter electrode CT is formed in a comb-teeth shape. Here, symbol PE indicates cutout portions of the counter electrode CT, and the pixel electrode which is exposed from the cutout portions are viewed. Further, an orientation film ORI 1 is formed to cover a topmost surface of the counter electrode CT.
[0067] On a main surface of a CF substrate SUB 2 , color filters CF which are defined from each other by a black matrix BM are formed in the same manner as the embodiment 1 and the embodiment 2, and an orientation film ORI 2 is formed on a topmost surface of the CF substrate SUB 2 . Each color filter CF is basically constituted of unit pixels (sub pixels) of three colors consisting of red (R), green (G), and blue (B), and a color pixel (pixel) is constituted of the unit pixels of the three colors.
[0068] A liquid crystal LC is sealed in the inside of a space between the orientation film ORI 1 of the TFT substrate SUB 1 and the orientation film ORI 2 of the CF substrate SUB 2 . With respect to the liquid crystal LC which is driven by the thin film transistor TFT, the orientation direction of the liquid crystal is rotated by a component parallel to a surface of the substrate of an electrical field E which is generated between the pixel electrode PX and the counter electrode CT in a plane parallel to the substrate surface thus controlling the lighting and non-lighting of the pixel.
[0069] In the embodiment 3, A SiN film having a film thickness of 300 nm is formed as the fifth insulation film INS 5 . The patterning of the fifth insulation film INS 5 is substantially equal to the patterning of the fifth insulation film adopted in the embodiment 1. After the formation of the fifth insulation film INS 5 , the photosensitive resist (PC-452 made by JSR) is filled in the contact hole CH thus forming sixth insulation film INS 6 . The patterning of the photosensitive resist is substantially equal to the patterning of the photosensitive resist adopted in the embodiment 2. The forming process of the counter electrode CT in the embodiment 3 is substantially equal to the forming process of the counter electrode CT adopted in the embodiments 1, 2.
[0070] A driving method of the liquid crystal display device of the embodiment 3 is explained hereinafter by focusing on points which make this embodiment 3 different from the embodiment 2. In the embodiment 3, the insulation film which is arranged between the pixel electrode PX and the counter electrode CT exhibits a high dielectric constant, and the smaller the film thickness of the insulation film, an electric field applied to the liquid crystal is increased thus eventually lowering a liquid crystal drive voltage (see FIG. 7 , FIG. 8 ).
[0071] FIG. 7 is an explanatory view of a transmissive brightness-voltage characteristic due to a dielectric constant of a fifth insulation film for explaining the embodiment 3, while FIG. 8 is an explanatory view of a transmissive brightness-voltage characteristic due to a film thickness of a fifth insulation film for explaining the embodiment 3. In FIG. 7 and FIG. 8 , symbol V indicates a liquid crystal drive voltage, symbol Tt indicates transmissivity, ε 5 indicates the dielectric constant of the fifth insulation film INS 5 , and symbol t 5 indicates a film thickness of the fifth insulation film INS 5 . Here, a width W of the teeth-like counter electrode CT and an electrode distance L of the counter electrodes CT is 4 μm and 6 μm respectively.
[0072] In the embodiment 2, a film thickness of the resin having a dielectric constant of 3.3 which constitutes the fifth insulation film INS 5 may be set to a value less than 300 nm. However, this resin exhibits a poor insulation dielectric strength and hence, a leak current is generated between the pixel electrode and the counter electrode thus lowering a liquid holding voltage. To the contrary, in the embodiment 3, at a portion where the pixel electrode is leveled, by forming the fifth insulation film INS 5 using SiN having a high dielectric constant and a high insulation dielectric strength (dielectric constant: 6.7), it is possible to realize the low drive voltage and the suppression of leak current. Further, at a portion which has the irregular surface such as the contact hole, by adopting the stacked structure consisting of the fifth insulation film INS 5 and the sixth insulation film INS 6 , it is possible to prevent the short-circuiting between the pixel electrode and the counter electrode and hence, the surface of the fifth insulation film INS 5 can be leveled whereby it is possible to realize the enhancement of the liquid crystal orientation restricting force. | The present invention realizes a bright image display by enhancing a numerical aperture of pixels. At least a portion of a pixel electrode is overlapped to a thin film transistor by way of a first insulation film, the pixel electrode is connected to an output electrode of the thin film transistor via a contact hole which is formed in the first insulation film, the counter electrode is arranged above the pixel electrode by way of a second insulation film in a state that the counter electrode is overlapped to the pixel electrode, the counter electrode is formed at a position avoiding the contact hole formed in the first insulation film as viewed in a plan view, and at least a portion of the counter electrode is overlapped to the thin film transistor. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. patent application Ser. No. 11/156,215, filed Jun. 17, 2005 and entitled “Wireless Architecture and Support for Process Control Systems,” now U.S. Pat. No. 7,436,797, which is hereby expressly incorporated by reference herein. This application is also related to U.S. patent application Ser. No. 10/464,087, filed Jun. 18, 2003 and entitled “Self-Configuring Communication Networks for use with Processing Control Systems,” now U.S. Pat. No. 7,460,865, which is hereby expressly incorporated by reference herein.
FIELD OF TECHNOLOGY
Methods and apparatuses are disclosed for providing wireless communications within a distributed process control system which establish and maintain consistent wireless communication connections between different remote devices and a base computer in a process control system.
BACKGROUND
Process control systems are widely used in factories and/or plants in which products are manufactured or processes are controlled (e.g., chemical manufacturing, power plant control, etc.). Process control systems are also used in the harvesting of natural resources such as, for example, oil and gas drilling and handling processes, etc. In fact, virtually any manufacturing process, resource harvesting process, etc. can be automated through the application of one or more process control systems. It is believed the process control systems will eventually be used more extensively in agriculture as well.
The manner in which process control systems are implemented has evolved over the years. Older generations of process control systems were typically implemented using dedicated, centralized hardware and hard-wired connections.
However, modern process control systems are typically implemented using a highly distributed network of workstations, intelligent controllers, smart field devices, and the like, some or all of which may perform a portion of an overall process control strategy or scheme. In particular, most modern process control systems include smart field devices and other process control components that are communicatively coupled to each other and/or to one or more process controllers via one or more digital data buses. In addition to smart field devices, modern process control systems may also include analog field devices such as, for example, 4-20 milliamp (mA) devices, 0-10 volts direct current (VDC) devices, etc., which are typically directly coupled to controllers as opposed to a shared digital data bus or the like.
In a typical industrial or process plant, a distributed control system (DCS) is used to control many of the industrial processes performed at the plant. The plant may have a centralized control room having a computer system with user input/output (I/O), a disc I/O, and other peripherals known in the computing art with one or more process controllers and process I/O subsystems communicatively connected to the centralized control room. Additionally, one or more field devices are typically connected to the I/O subsystems and to the process controllers to implement control and measurement activities within the plant. While the process I/O subsystem may include a plurality of I/O ports connected to the various field devices throughout the plant, the field devices may include various types of analytical equipment, silicon pressure sensors, capacitive pressure sensors, resistive temperature detectors, thermocouples, strain gauges, limit switches, on/off switches, flow transmitters, pressure transmitters, capacitance level switches, weigh scales, transducers, valve positioners, valve controllers, actuators, solenoids, indicator lights or any other device typically used in process plants.
As used herein, the term “field device” encompasses these devices, as well as any other device that performs a function in a control system. In any event, field devices may include, for example, input devices (e.g., devices such as sensors that provide status signals that are indicative of process control parameters such as, for example, temperature, pressure, flow rate, etc.), as well as control operators or actuators that perform actions in response to commands received from controllers and/or other field devices.
Traditionally, analog field devices have been connected to the controller by two-wire twisted pair current loops, with each device connected to the controller by a single two-wire twisted pair. Analog field devices are capable of responding to or transmitting an electrical signal within a specified range. In a typical configuration, it is common to have a voltage differential of approximately 20-25 volts between the two wires of the pair and a current of 4-20 mA running through the loop. An analog field device that transmits a signal to the control room modulates the current running through the current loop, with the current being proportional to the sensed process variable.
An analog field device that performs an action under control of the control room is controlled by the magnitude of the current through the loop, which current is modulated by the I/O port of the process I/O system, which in turn is controlled by the controller. Traditional two-wire analog devices having active electronics can also receive up to 40 milliwatts of power from the loop. Analog field devices requiring more power are typically connected to the controller using four wires, with two of the wires delivering power to the device. Such devices are known in the art as four-wire devices and are not power limited, as typically are two-wire devices.
A discrete field device can transmit or respond to a binary signal. Typically, discrete field devices operate with a 24 volt signal (either AC or DC), a 110 or 240 volt AC signal, or a 5 volt DC signal. Of course, a discrete device may be designed to operate in accordance with any electrical specification required by a particular control environment. A discrete input field device is simply a switch which either makes or breaks the connection to the controller, while a discrete output field device will take an action based on the presence or absence of a signal from the controller.
Historically, most traditional field devices have had either a single input or a single output that was directly related to the primary function performed by the field device. For example, the only function implemented by a traditional analog resistive temperature sensor is to transmit a temperature by modulating the current flowing through the two-wire twisted pair, while the only function implemented by a traditional analog valve positioner is to position a valve somewhere between a fully open and a fully closed position based on the magnitude of the current flowing through the two-wire twisted pair.
More recently, field devices that are part of hybrid systems become available that superimpose digital data on the current loop used to transmit analog signals. One such hybrid system is known in the control art as the Highway Addressable Remote Transducer (HART) protocol. The HART system uses the magnitude of the current in the current loop to send an analog control signal or to receive a sensed process variable (as in the traditional system), but also superimposes a digital carrier signal upon the current loop signal. The HART protocol makes use of the Bell 202 Frequency Shift Keying (FSK) standard to superimpose the digital signals at a low level on top of the 4-20 mA analog signals. This enables two-way field communication to take place and makes it possible for additional information beyond just the normal process variable to be communicated to/from a smart field instrument. The HART protocol communicates at 1200 bps without interrupting the 4-20 mA signal and allows a host application (master) to get two or more digital updates per second from a field device. As the digital FSK signal is phase continuous, there is no interference with the 4-20 mA signal.
The FSK signal is relatively slow and can therefore provide updates of a secondary process variable or other parameter at a rate of approximately 2-3 updates per second. Generally, the digital carrier signal is used to send secondary and diagnostic information and is not used to realize the primary control function of the field device. Examples of information provided over the digital carrier signal include secondary process variables, diagnostic information (including sensor diagnostics, device diagnostics, wiring diagnostics, and process diagnostics), operating temperatures, a sensor temperature, calibration information, device ID numbers, materials of construction, configuration or programming information, etc. Accordingly, a single hybrid field device may have a variety of input and output variables and may implement a variety of functions.
More recently, a newer control protocol has been defined by the Instrument Society of America (ISA). The new protocol is generally referred to as Fieldbus, and is specifically referred to as SP 50 , which is as acronym for Standards and Practice Subcommittee 50 . The Fieldbus protocol defines two subprotocols. An H 1 Fieldbus network transmits data at a rate up to 31.25 kilobits per second and provides power to field devices coupled to the network. An H 2 Fieldbus network transmits data at a rate up to 2.5 megabits per second, does not provide power to field devices connected to the network, and is provided with redundant transmission media. Fieldbus is a nonproprietary open standard and is now prevalent in the industry and, as such, many types of Fieldbus devices have been developed and are in use in process plants. Because Fieldbus devices are used in addition to other types of field devices, such as HART and 4-20 mA devices, a separate support and I/O communication structure is associated with each of these different types of devices.
Newer smart field devices, which are typically all digital in nature, have maintenance modes and enhanced functions that are not accessible from or compatible with older control systems. Even when all components of a distributed control system adhere to the same standard (such as the Fieldbus standard), one manufacturer's control equipment may not be able to access the secondary functions or secondary information provided by another manufacturer's field devices.
Thus, one particularly important aspect of process control system design involves the manner in which field devices are communicatively coupled to each other, to controllers and to other systems or devices within a process control system or a process plant. In general, the various communication channels, links and paths that enable the field devices to function within the process control system are commonly collectively referred to as an input/output (I/O) communication network.
The communication network topology and physical connections or paths used to implement an I/O communication network can have a substantial impact on the robustness or integrity of field device communications, particularly when the I/O communications network is subjected to environmental factors or conditions associated with the process control system. For example, many industrial control applications subject field devices and their associated I/O communication networks to harsh physical environments (e.g., high, low or highly variable ambient temperatures, vibrations, corrosive gases or liquids, etc.), difficult electrical environments (e.g., high noise environments, poor power quality, transient voltages, etc.), etc. In any case, environmental factors can compromise the integrity of communications between one or more field devices, controllers, etc. In some cases, such compromised communications could prevent the process control system from carrying out its control routines in an effective or proper manner, which could result in reduced process control system efficiency and/or profitability, excessive wear or damage to equipment, dangerous conditions that could damage or destroy equipment, building structures, the environment and/or people, etc.
In order to minimize the effect of environmental factors and to assure a consistent communication path, I/O communication networks used in process control systems have historically been hardwired networks, with the wires being encased in environmentally protected materials such as insulation, shielding and conduit. Also, the field devices within these process control systems have typically been communicatively coupled to controllers, workstations, and other process control system components using a hardwired hierarchical topology in which non-smart field devices are directly coupled to controllers using analog interfaces such as, for example, 4-20 mA, 0-10 VDC, etc. hardwired interfaces or I/O boards. Smart field devices, such as Fieldbus devices, are also coupled via hardwired digital data busses, which are coupled to controllers via smart field device interfaces.
While hardwired I/O communication networks can initially provide a robust I/O communication network, their robustness can be seriously degraded over time as a result of environmental stresses (e.g., corrosive gases or liquids, vibration, humidity, etc.). For example, contact resistances associated with the I/O communication network wiring may increase substantially due to corrosion, oxidation and the like. In addition, wiring insulation and/or shielding may degrade or fail, thereby creating a condition under which environmental electrical interference or noise can more easily corrupt the signals transmitted via the I/O communication network wires. In some cases, failed insulation may result in a short circuit condition that results in a complete failure of the associated I/O communication wires.
Additionally, hardwired I/O communication networks are typically expensive to install, particularly in cases where the I/O communication network is associated with a large industrial plant or facility that is distributed over a relatively large geographic area, for example, an oil refinery or chemical plant that consumes several acres of land. In many instances, the wiring associated with the I/O communication network must span long distances and/or go through, under or around many structures (e.g., walls, buildings, equipment, etc.) Such long wiring runs typically involve substantial amounts of labor, material and expense. Further, such long wiring runs are especially susceptible to signal degradation due to wiring impedances and coupled electrical interference, both of which can result in unreliable communications.
Moreover, such hardwired I/O communication networks are generally difficult to reconfigure when modifications or updates are needed. Adding a new field device typically requires the installation of wires between the new field device and a controller. Retrofitting a process plant in this manner may be very difficult and expensive due to the long wiring runs and space constraints that are often found in older process control plants and/or systems. High wire counts within conduits, equipment and/or structures interposing along available wiring paths, etc., may significantly increase the difficulty associated with retrofitting or adding field devices to an existing system. Exchanging an existing field device with a new device having different field wiring requirements may present the same difficulties in the case where more and/or different wires have to be installed to accommodate the new device. Such modifications may often result in significant plant downtime.
It has been suggested to use wireless I/O communication networks to alleviate some of the difficulties associated with hardwired I/O networks. For example, Tapperson et al., U.S. patent application Ser. No. 09/805,124 discloses a system which provides wireless communications between controllers and field devices to augment or supplement the use of hardwired communications. However, most, if not all, wireless I/O communication networks actually implemented within process plants today are implemented using relatively expensive hardware devices (e.g., wireless enabled routers, hubs, switches, etc.), most of which consume a relatively large amount of power. Further, intermittent interferences, such as the passing of trucks, trains, environmental or weather related conditions, etc., make wireless communication networks unreliable and therefore problematic.
In addition, known wireless I/O communication networks, including the hardware and software associated therewith, generally use point-to-point communication paths that are carefully selected during installation and fixed during subsequent operation of the system. Establishing fixed communication paths within these wireless I/O communication networks typically involves the use of one or more experts to perform an expensive site survey that enables the experts to determine the types and/or locations of the transceivers and other communication equipment. Further, once the fixed point-to-point communication paths have been selected via the site survey results, one or more of the experts must then configure equipment, tune antennas, etc. While the point-to-point paths are generally selected to insure adequate wireless communications, changes within the plant, such as the removal or addition of equipment, walls, or other structures may make the initially selected paths less reliable, leading to unreliable wireless communications.
While wireless I/O communication networks can, for example, alleviate the long term robustness issues associated with hardwired communication paths, these wireless I/O communication networks are relatively inflexible and are considered by most in the process control industry to be too unreliable to perform important or necessary process control functions. For example, there is currently no easy manner of telling when a wireless communication is no longer functioning properly, or has degraded to the point that communications over the wireless link are likely to be unreliable or to cease altogether. As a result, current process control operators have very little faith in wireless communication networks when implemented for important and necessary process control functions.
Thus, due to the costs associated with installing a wireless I/O communication network (e.g., site surveys, expert configuration, etc.), and the relative little amount of faith that current process control system operators have in wireless communications, wireless I/O communication networks are often cost prohibitive for what they provide, particularly for relatively large process control systems such as those typically used in industrial applications.
SUMMARY OF THE DISCLOSURE
A wireless communication architecture for use in a process control system is disclosed which includes the use of mesh and possibly a combination of mesh and point-to-point communications to produce a more robust wireless communication network that can be easily set up, configured, changed and monitored, to thereby make the wireless communication network more robust, less expensive and more reliable. The wireless communication architecture is implemented in a manner that is independent of the specific messages or virtual communication paths within the process plant and, in fact, the wireless communication network is implemented to allow virtual communication paths to be established and used within the process control system in a manner that is independent of the manner in which the wireless signals are sent between different wireless transmitting and receiving devices within the process plant.
In a refinement, one or more environmental nodes are used to control and optimize the operation of the wireless communication network. The environmental node(s) are linked to field “environmental” devices providing signals indicative of one or more environmental factors such as temperature, barometric pressure, humidity, rainfall and radio frequency (RF) ambient noise, amongst other environmental factors that could alter the operation of the network.
In another refinement, the network includes a main controller linked to a wireless card. The wireless card is in communication with a repeater node which, in turn, is in communication with a field node. The field node is linked to a plurality of field devices. In another refinement, the repeater node is eliminated. In another refinement, an environmental node and environmental detection devices as discussed above are incorporated with or without one or more repeater nodes. In a further refinement, the field and environmental nodes include a plurality of ports for communication with the field devices.
In a refinement, the wireless communication network is set up to transmit HART communication signals between different devices within the process plant to thereby enable a robust wireless communication network to be used in a process plant or any other environment having HART capable devices.
In an embodiment, a process control wireless communication network is disclosed which comprises a base node, a field node, an environmental node and a host. The base node is communicatively coupled to the host. The base, field and environmental nodes each comprise a wireless conversion unit and a wireless transceiver. The wireless transceivers of the base, the field and environmental nodes effect wireless communication among the base, field and environmental nodes. The field node comprises at least one field device providing process controlled data. The environmental node comprises at least one field device providing data regarding environmental factors that may effect affect operation of the wireless communication network.
In a refinement, the network also comprises a repeater node comprising a wireless conversion unit in a wireless transceiver. The repeater node effects wireless communications amongst the base, field and environmental node.
In another refinement, the environmental node comprises a plurality of field devices, each providing data selected from the group consisting of temperature, barometric pressure, humidity, rainfall and radio frequency ambient noise.
In another refinement, at least some of the field devices are HART protocol devices. In another refinement, at least some of the field devices are FIELDBUS™ protocol devices.
In another refinement, the network comprises a plurality of environmental nodes strategically placed about a process area for communicating environmental data for different locations within the process area.
In a refinement, the base, environmental and field nodes form a mesh communications network, providing multiple communication pathway options between any two wireless nodes. In another refinement, the base, environmental and field nodes form a point-to-point communications network. In yet another refinement, the network comprises a switch device to convert the base, environmental and field nodes from a mesh communications network to a point-to-point communications network and vice versa.
Communication tools are also disclosed to enable an operator to view a graphic of the wireless communication system to easily determine the actual wireless communication paths established within a process plant, to determine the strength of any particular path and to determine or view the ability of signals to propagate through the wireless communication network from a sender to a receiver to thereby enable a user or operator to assess the overall operational capabilities of the wireless communication network.
In a refinement, the communication tools include one or more of graphical topology maps illustrating connectivity between nodes, tabular presentations showing the connectivity matrix and hop counts and actual maps showing location and connectivity of the hardware devices. The monitor that illustrates wireless communications between the base, field and environmental nodes of the network may be associated with the base node or the host. In another refinement, the topology screen display also illustrates structural features of the process area or environment in which the base, field and environmental nodes are disposed. In another refinement, the host is programmed to provide a tabular screen display listing hop counts for communications between the various nodes of the network.
In another refinement, the wireless communication network is configured to transmit Fieldbus communication signals between different devices within the process plant to thereby enable a robust wireless communication network to be used in a process plant or environment having Fieldbus capable devices in combination with or instead of HART capable devices.
In a refinement, a method for controlling a process is disclosed which comprises receiving field data from at least one field device, transmitting the field data wirelessly from a field node to a base node, converting the field data to a different protocol, transmitting the field data of the different protocol to a routing node, determining at the routing node an object device for receiving the field data of the different protocol, and sending the field data of the different protocol to the object device.
In another refinement, a method for monitoring a wireless process control network is disclosed which comprises receiving environmental data from one or more environmental field devices of an environmental node, wirelessly transmitting the environmental data to a base node, transmitting the environmental data to a host, interpreting the environmental data at the host, sending a command from the host to the base node to adjust at least one operating parameter of the wireless network based upon the environmental data, and transmitting the command from the base node to at least one field node comprising at least one field device for executing the command.
Other advantages and features will become apparent upon reading the following detailed description and independent claims, an upon reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
For more complete understanding of this disclosure, reference should now be made to the embodiments illustrated in greater detail in the accompanying drawings and described below by way of examples. In the drawings:
FIG. 1 is a combined block and schematic diagram of a conventional hardwired distributed control system;
FIG. 2 is a combined block and schematic diagram of a wireless communication network within a portion of a process environment designed in accordance with this disclosure;
FIG. 3 is a diagram of a wireless communication network within a process environment illustrating both mesh and point-to-point wireless communications;
FIG. 4 is a block diagram of a mesh and point-to-point enabled communication device that may be used to switch between mesh and point-to-point communications within the communication network of FIG. 3 .
FIG. 5 is an example of a geometric topology screen display created by a wireless network analysis tool illustrating the wireless communications between different devices within the wireless communication system designed in accordance with this disclosure;
FIG. 6 is an example screen display presented in tabular form and created by a wireless network analysis tool illustrating the number of hops or the hop count between each of the wireless communication devices within a disclosed wireless communication system;
FIG. 7 is an example of a topology screen display created by a disclosed wireless network analysis tool illustrating the wireless communications within a graphic of a plant layout to enable an operator or other user to view the specific communications occurring within the wireless communication network and potential physical obstacles presented by the plant layout;
FIG. 8 is an example screen display created by a disclosed wireless network analysis tool allowing a user or operator to specify the channel routing and identification within the wireless communication network;
FIG. 9 is an example screen display created by a wireless network analysis tool illustrating graphical displays of information about the wireless communications between different devices within the wireless communication system to enable a user or operator to analyze the operational capabilities and parameters of the wireless communication network; and
FIG. 10 is a block diagram of a wireless communication device that implements a HART communication protocol wirelessly using a second communication protocol, e.g. the EMBER® protocol.
It should be understood that the drawings are not to scale and that the embodiments are illustrated by graphic symbol, phantom lines, diagrammatic representations and fragmentary views. In certain instances, details have been omitted which are not necessary for an understanding of the disclosed embodiments and methods or which render other details difficult to perceive. This disclosure is not limited to the particular embodiments illustrated herein.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 illustrates a typical hardwired distributed process control system 10 which includes one or more process controllers 12 connected to one or more host workstations or computers 14 (which may be any type of personal computer or workstation). The process controllers 12 are also connected to banks of input/output (I/O) devices 20 , 22 each of which, in turn, is connected to one or more field devices 25 - 39 . The controllers 12 , which may be, by way of example only, DeItaV™ controllers sold by Fisher-Rosemount Systems, Inc., are communicatively connected to the host computers 14 via, for example, an Ethernet connection 40 or other communication link. Likewise, the controllers 12 are communicatively connected to the field devices 25 - 39 using any desired hardware and software associated with, for example, standard 4-20 mA devices and/or any smart communication protocol such as the Fieldbus or HART protocols. As is generally known, the controllers 12 implement or oversee process control routines stored therein or otherwise associated therewith and communicate with the devices 25 - 39 to control a process in any desired manner.
The field devices 25 - 39 may be any types of devices, such as sensors, valves, transmitters, positioners, etc. while the I/O cards within the banks 20 and 22 may be any types of I/O devices conforming to any desired communication or controller protocol such as HART, Fieldbus, Profibus, etc. In the embodiment illustrated in FIG. 1 , the field devices 25 - 27 are standard 4-20 mA devices that communicate over analog lines to the I/O card 22 A. The field devices 28 - 31 are illustrated as HART devices connected to a HART compatible I/O device 20 A. Similarly, the field devices 32 - 39 are smart devices, such as Fieldbus field devices, that communicate over a digital bus 42 or 44 to the I/O cards 20 B or 22 B using, for example, Fieldbus protocol communications. Of course, the field devices 25 - 39 and the banks of I/O cards 20 and 22 could conform to any other desired standard(s) or protocols besides the 4-20 mA, HART or Fieldbus protocols, including any standards or protocols developed in the future.
Each of the controllers 12 is configured to implement a control strategy using what are commonly referred to as function blocks, wherein each function block is a part (e.g., a subroutine) of an overall control routine and operates in conjunction with other function blocks (via communications called links) to implement process control loops within the process control system 10 . Function blocks typically perform one of an input function, such as that associated with a transmitter, a sensor or other process parameter measurement device, a control function, such as that associated with a control routine that performs PID, fuzzy logic, etc. control, or an output function that controls the operation of some device, such as a valve, to perform some physical function within the process control system 10 . Of course hybrid and other types of function blocks exist. Groups of these function blocks are called modules. Function blocks and modules may be stored in and executed by the controller 12 , which is typically the case when these function blocks are used for, or are associated with standard 4-20 mA devices and some types of smart field devices, or may be stored in and implemented by the field devices themselves, which may be the case with Fieldbus devices. While the control system 10 illustrated in FIG. 1 is described as using function block control strategy, the control strategy could also be implemented or designed using other conventions, such as ladder logic, sequential flow charts, etc. and using any desired proprietary or non-proprietary programming language.
As evident from the discussion of FIG. 1 , the communications between the host workstations 14 and the controllers 12 and between the controllers 12 and the field devices 25 - 39 are implemented with hardwired communication connections, including one or more of HART, Fieldbus and 4-20 mA hardwired communication connections. However, as noted above, it is desirable to replace or augment the hardwired communication connections within the process environment of FIG. 1 with wireless communications in a manner that is reliable, that is easy to set up and configure, that provides an operator or other user with the ability to analyze or view the functioning capabilities of the wireless network, etc.
FIG. 2 illustrates a wireless communication network 60 that may be used to provide communications between the different devices illustrated in FIG. 1 and, in particular, between the controllers 12 (or the associated I/O devices 22 ) of FIG. 1 and the field devices 25 - 39 , between the controllers 12 and the host workstations 14 or between the host workstations 14 and the field devices 25 - 39 of FIG. 1 . However, it will be understood that the wireless communication network 60 of FIG. 2 could be used to provide communications between any other types or sets of devices within a process plant or a process environment.
The communication network 60 of FIG. 2 is illustrated as including various communication nodes including one or more base nodes 62 , one or more repeater nodes 64 , one or more environment nodes 66 (illustrated in FIG. 2 as nodes 66 a and 66 b ) and one or more field nodes 68 (illustrated in FIG. 2 as nodes 68 a , 68 b and 68 c ). Generally speaking, the nodes of the wireless communication network 60 operate as a mesh type communication network, wherein each node receives a communication, determines if the communication is ultimately destined for that node and, if not, repeats or passes the communication along to any other nodes within communication range. As is known, any node in a mesh network may communicate with any other node in range to forward communications within the network, and a particular communication signal may go through multiple nodes before arriving at the desired destination.
As illustrated in FIG. 2 , the base node 62 includes or is communicatively coupled to a work station or a host computer 70 which may be for example any of the hosts or workstations 14 of FIG. 1 . While the base node 62 is illustrated as being linked to the workstation 70 via a hardwired Ethernet connection 72 , any other communication link may be used instead. As will be described in more detail later, the base node 62 includes a wireless conversion or communication unit 74 and a wireless transceiver 76 to effect wireless communications over the network 60 . In particular, the wireless conversion unit 74 takes signals from the workstation or host 70 and encodes these signals into a wireless communication signal which is then sent over the network 60 via the transmitter portion of the transceiver 76 . Conversely, the wireless conversion unit 74 decodes signals received via the receiver portion of the transceiver 76 to determine if that signal is destined for the base node 62 and, if so, further decodes the signal to strip off the wireless encoding to produce the original signal generated by the sender at a different node 64 , 66 or 68 within the network 60 .
As will be understood, in a similar manner, each of the other communication nodes including the repeater nodes 64 , the environmental nodes 66 and the field nodes 68 includes a communication unit 74 and a wireless transceiver 76 for encoding, sending and decoding signals sent via the wireless mesh network 60 . While the different types of nodes 64 , 66 , 68 within the communication network 60 differ in some important ways, each of these nodes generally operates to receive wireless signals, decode the signal enough to determine if the signal is destined for that node (or a device connected to that node outside of the wireless communication network 60 ), and repeat or retransmit the signal if the signal is not destined for that node and has not previously been transmitted by that node. In this manner, signals are sent from an originating node to all the nodes within wireless communication range, each of the nodes in range which are not the destination node then retransmits the signal to all of the other nodes within range of that node, and the process continues until the signal has propagated to all of the nodes within range of at least one other node.
However, the repeater node 64 operates to simply repeat signals within the communication network 60 to thereby relay a signal from one node through the repeater node 64 to a second node 62 , 66 or 68 . Basically, the function of the repeater node 64 is to act as a link between two different nodes to assure that a signal is able to propagate between the two different nodes when these nodes are not or may not be within direct wireless communication range of one another. Because the repeater node 64 is not generally tied to other devices at the node, the repeater node 64 only needs to decode a received signal enough to determine if the signal is a signal that has been previously repeated by the repeater node (that is, a signal that was sent by the repeater node at a previous time and which is simply being received back at the repeater node because of the repeating function of a different node in the communication network 60 ). If the repeater node has not received a particular signal before, the repeater node 64 simply operates to repeat this signal by retransmitting that signal via the transceiver 74 of the repeater node 64 .
On the other hand, each of the field nodes 68 is generally coupled to one or more devices within the process plant environment and, generally speaking, is coupled to one or more field devices, illustrated as field devices 80 - 85 in FIG. 2 . The field devices 80 - 85 may be any type of field devices including, for example, four-wire devices, two-wire devices, HART devices, Fieldbus devices, 4-20 mA devices, smart or non-smart devices, etc. For the sake of illustration, the field devices 80 - 85 of FIG. 2 are illustrated as HART field devices, conforming to the HART communication protocol. Of course, the devices 80 - 85 may be any type of device, such as a sensor/transmitter device, a valve, a switch, etc. Additionally, the devices 80 - 85 may be other than traditional field devices such as controllers, I/O devices, work stations, or any other types of devices.
In any event, the field node 68 a , 68 b , 68 c includes signal lines attached to their respective field devices 80 - 85 to receive communications from and to send communications to the field devices 80 - 85 . Of course, these signal lines may be connected directly to the devices 80 - 85 , in this example, a HART device, or to the standard HART communication lines already attached to the field devices 80 - 85 . If desired, the field devices 80 - 85 may be connected to other devices, such as I/O devices 20 A or 22 A of FIG. 1 , or to any other desired devices via hardwired communication lines in addition to being connected to the field nodes 68 a , 68 b , 68 c . Additionally, as illustrated in FIG. 2 , any particular field node 68 a , 68 b , 68 c may be connected to a plurality of field devices (as illustrated with respect to the field node 68 c , which is connected to four different field devices 82 - 85 ) and each field node 68 a , 68 b , 68 c operates to relay signals to and from the field devices 80 - 85 to which it is connected.
In order to assist in the management in the operation of the communication network 60 , the environmental nodes 66 are used. In this case, the environmental nodes 66 a and 66 b include or are communicatively connected to devices or sensors 90 - 92 that measure environmental parameters, such as the humidity, temperature, barometric pressure, rainfall, or any other environmental parameters which may affect the wireless communications occurring within the communication network 60 . As discussed in more detail below, this information may be useful in analyzing and predicting problems within the communication network, as many disruptions in wireless communications are at least partially attributable to environmental conditions. If desired, the environmental sensors 90 - 92 may be any kind of sensor and may include, for example, HART sensors/transmitters, 4-20 mA sensors or on board sensors of any design or configuration. Of course, each environmental node 66 a , 66 b may include one or more environmental sensors 90 - 92 and different environmental nodes may include the same or different types or kinds of environmental sensors if so desired. Likewise, if desired, one or more of the nodes 66 a , 66 b may include an electromagnetic ambient noise measurement device 93 to measure the ambient electromagnetic noise level, especially at the wavelengths used by the communication network 60 to transmit signals. Of course, if a spectrum other than the RF spectrum is used by the communication network 60 , a different type of noise measurement device may be included in one or more of the environmental nodes 66 . Still further, while the environmental nodes 66 of FIG. 2 are described as including environmental measurement devices or sensors 90 - 93 , any of the other nodes 68 could include those measurement devices so that an analysis tool may be able to determine the environmental conditions at each node when analyzing the operation of the communication network 60 .
Using the communication system 60 of FIG. 2 , an application running on the workstation 70 can send packets of data to and receive packets of wireless data from the wireless base card 74 residing in a standard controller 75 at the base node 62 . This controller 75 may be, for example, a DeltaV controller and the communications may be the same as with a standard I/O card via the Ethernet connection to the DeltaV controller. The I/O card in this case includes a wireless base card 74 , though as far as the controller and PC Application goes, it appears as a standard HART I/O card.
In this case, the wireless card 74 at the base node 62 encodes the data packet for wireless transmission and the transceiver 76 at the base node 62 transmits the signal. FIG. 2 illustrates that the transmitted signal may go directly to some of the field nodes such as nodes 68 a and 68 b , but may also propagate to other field nodes, such as node 68 c , via the repeater node 64 . In the same manner, signals created at and propagated by the field nodes 68 may go directly to the base node 62 and other field nodes 68 or may be transmitted through other nodes such as the repeater node 64 or another field node before being transmitted to the base node 62 . Thus, the communication path over the wireless network 60 may or may not go through a repeater node 64 and, in any particular case, may go through numerous nodes before arriving at the destination node. If a sending node is in direct communication reach of the base unit 62 , then it will exchange data directly. Whether or not the packets pass through a repeater node 64 is completely transparent to the end user, or even to the card firmware.
It will be noted that FIG. 2 is a schematic diagram and the placement of the environmental nodes 66 a , 66 b relative to the field nodes 68 a - 68 c are not intended to be relative to their actual placement in an actual process control area. Rather, the environmental nodes 66 a , 66 b (and other environmental nodes not pictured or a single environmental node) are intended to be placed about the process control area in a logical and strategic manner as shown in FIG. 7 . In other words, environmental nodes 66 should be placed at spaced apart location, such as at opposing ends of large obstacles or pieces of equipment or near roadways where interference from moving vehicles may be present. Also, environmental nodes should be placed both indoors and outdoors if applicable. The network of environmental nodes 66 is intended to be used by the base node 62 and host 70 as a means for monitoring the operation of the wireless network 60 and modifying the operation of the network 60 by increasing or decreasing signal strength, gain, frequency etc.
It will be noted that the field nodes 68 are placed at or near various process stations. The field nodes 68 may be important safety devices or may be used to monitor and/or control various processes. Further, more than one repeater node 64 may be used and, in fact, FIG. 2 is but one example as it may be determined that only a single environmental node 66 is necessary, that more than one or no repeater nodes 64 are needed and that fewer than three or more than three field nodes 68 are necessary.
Turning to FIGS. 3 and 4 , it is anticipated that the wireless network 60 of FIG. 2 may need to be switched back and forth between mesh and point-to-point communication modes. FIG. 3 illustrates a network 100 with a base node 101 in communication with repeater nodes 102 a , 102 b , 102 c . The repeater nodes 102 a - 102 c are, in turn, in communication with a plurality or a cluster of either environmental nodes, field nodes or combination of the two as shown generally at 104 . A point-to-point wireless communication system for FIG. 3 is shown in solid line while an alternative mesh configuration is shown in solid phantom line.
Turning to FIG. 4 , a switch device 105 is shown schematically which may be disposed in the base node 101 in addition to the wireless transceiver 76 . The switch 105 is intended to convert the network 100 from a mesh wireless network as shown by the phantom lines in FIG. 3 to a point-to-point wireless network as shown by way of example in the solid line of FIG. 3 . Of course, the point-to-point communications can be configured in any manner and the solid lines shown in FIG. 3 are but one example. The switch device 105 as shown in FIG. 4 can include an electronic switch element 106 that shifts the device 105 between a mesh wireless transceiver 76 a and a point-to-point wireless transceiver 76 b.
As noted above, the disclosed network 60 includes a base node 62 and host 70 that may be programmed to provide a variety of graphical interfaces that will be useful to the operator. Examples of such graphical interfaces are shown in FIGS. 5-9 . Turning to FIG. 5 , a geometric topology screen display 110 is disclosed which illustrates a wireless network between a base node BA and a plurality of other nodes which may be one or more repeater nodes, field nodes and environmental nodes numbered in FIG. 5 as 03 , 04 , 05 , 07 , 08 , 09 , 10 ( 0 A), and 11 ( 0 B). The topology display 110 of FIG. 5 illustrates a successful communication between two nodes with a solid line, one example of which is the communication between the base node BA and the node 7 . A successful communication in one direction only is illustrated by a line with cross hatches, one example of which is the line between the nodes 03 and 10 ( 0 A). An unsuccessful communication is indicated by a dashed or phantom line, one example of which is the lack of communication illustrated by the dashed line between nodes 05 and 11 ( 0 B). FIG. 5 also illustrates the “hop count” between nodes. For example, looking at nodes 04 and 07 , the dashed or phantom line between nodes 04 and 07 of FIG. 5 make it clear that there is no direct wireless communication between nodes 04 and 07 while there is communication between nodes 04 and 05 and one-way communication between nodes 05 and 07 . Thus, for one-way communication between nodes 04 and 07 , there is a hop count of 2 (node 04 to node 05 and node 05 to node 07 ). Alternatively, for two-way communication between nodes 04 and 07 , there is also a hop count of 2 (node 07 to node 03 and node 03 to node 04 ). Obviously, the lower the hop count the better and the more reliable the communication.
The hop counts for the network shown in FIG. 5 are shown in tabular form in FIG. 6 . The nodes labeled 10 and 11 in FIG. 5 are also indicated as 0 A and 0 B in FIG. 6 . The base node BA communicates directly with nodes 03 through 0 B and therefore the hop count between the base node BA and any one of 03 through 0 B is one as indicated in the top row of the table shown in FIG. 6 . Turning to the second row of the table of FIG. 6 , it will be noted that the hop count between node 03 and any of the other nodes is also 1 as node 03 of FIG. 5 includes no dashed lines emanating from it. However, turning to the third row of the table of FIG. 6 and referring to FIG. 5 , it will be noted that node 04 includes a dashed line extended between node 04 and node 07 and therefore direct communication between node 04 and node 07 is not possible. Thus, to connect from node 04 to node 07 , the communication proceeds through node 05 for a hop count of 2. Still further, because there is a cross-hatched line between node 04 and node 09 in FIG. 5 , direct two-way communication between node 04 and 09 is not possible. Accordingly, for two-way communication between nodes 04 and 09 , the communication must pass through node 08 as indicated in the table of FIG. 6 . All of the entries that are circled in FIG. 6 indicate a hop count of 2.
Turning to FIG. 7 , a topology map similar to that shown in FIG. 5 is illustrated as an overlay of a map for an actual process environment. Specifically, each point is the location of 1 of the 9 nodes show in FIG. 5 and listed in the table of FIG. 6 . FIG. 7 provides the operator with an opportunity to view the wireless connectivities within the context of the actual operating environment. Global positioning system reference points are indicated at 111 , 112 so actual distances between the nodes can be determined.
Turning to FIG. 8 , the field devices 80 - 85 and 90 - 93 may appear to the base node 62 or host 70 as a standard HART device. This enables standard applications such as AMS software to run seamlessly on top of the wireless network 60 . To utilize the AMS software, the wireless field nodes 66 and 68 need to know how to route messages. This is accomplished by utilizing a routing map 120 as illustrated in FIG. 8 . This map 120 is stored in the nonvolatile memory of the base unit 62 , but also could be stored in the memory of the host 70 . The actual routing takes advantage of incorporating a base card that is identical to an 8 channel HART card. The routing tool then maps 8 virtual HART channels to remote field nodes and their channels. FIG. 8 illustrates a mapping configuration for 8 different devices. Each Field type wireless node may include 4 different HART channels, though the field device will have one unique ID. The actual target channel is embedded in the wireless packet. Each ID for each wireless unit is based on 2 bytes. The first byte is the network number and correlates to an actual radio channel in the wireless interface. The number of the first byte can range from 1 to 12. The second byte is the identification of the node in the network and can range from 1 to 15. When a node is initialized for a first time, its default address is 010 F, which means network 1 , address 15 . The exception to this address scheme is the base unit which always has BA as its first byte, the second byte representing which network the device is in.
Turning to FIG. 9 , another graphical presentation 130 for display at the host 70 ( FIG. 1 ) is shown. 4 graphs are shown, one on top of each other with time being plotted on the x-axes. The top graph 131 plots a total hop count for the entire system which, as shown, averages about 72 or slightly less. An increase in the hop count would provide a warning to the operator. The other graphs in FIG. 9 provide environmental information from the environmental node 66 shown in FIG. 2 . The graph 132 provides a reading of barometric pressure; the graph 133 provides a reading of humidity; and the graph 134 provides a reading of the general RF background noise within the operating frequency band. Other environmental indications not presented in FIG. 9 could be temperature and rainfall.
Turning to FIG. 10 , it will be noted that many of the devices 80 - 85 shown in FIG. 2 would be HART field devices, and therefore the field node 68 will be sending a HART signal to either a repeater node 64 or directly to a conversion node 140 which, in the embodiment shown in FIG. 10 , may be a separate element or may comprise part of the base node 62 . A HART signal may also be sent from an environmental node 66 as shown. The conversion node 140 includes software to convert the HART signal to a different protocol, e.g., the EMBER protocol used with low-power wireless networking software and radio technology. See http://www.cmbcr.com/http://www.ember.com/. Of course, other protocols are available and will be apparent to those skilled in the art. The conversion node 140 converts the HART signal to an EMBER data packet at 141 . The data packet includes an origin indication 142 and a destination indication 143 which is determined by software either in the base node 62 or in the conversion node 140 . The HART message 144 is sandwiched between the origin data 142 and destination data 143 . The signal is then sent to a routing node 145 which determines, from the destination information 143 , which object device 146 to send the data to. The routing node 145 then transmits the data through one or more repeaters 64 and/or field nodes 68 to the object device 146 . One type of software that could be used to convert the field device signal from one protocol (HART) to another protocol is the JTS software sold by Acugen (http://www.acugen.com/jts.htm).
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. | A wireless communication system for use in a process environment uses mesh and possibly a combination of mesh and point-to-point communications to produce a wireless communication network that can be easily set up, configured, changed and monitored, thereby making a wireless communication network that is less expensive, and more robust and reliable. The wireless communication system allows virtual communication paths to be established and used within the process control system in a manner that is independent of the manner in which the wireless signals are sent between different wireless transmitting and receiving devices within the process plant, to thereby operate in a manner that is independent of the specific messages or virtual communication paths within the process plant. Still further, communication analysis tools are provided to enable a user or operator to view the operation of the wireless communication network to thereby analyze the ongoing operation of the wireless communications within the wireless communication network. | 8 |
BACKGROUND OF THE INVENTION
The invention relates to a process and a device for continuous reeling of a pulp sheet, particularly a paper sheet, e.g. tissue, where the sheet runs over a reel drum and is later wound on a winding unit.
Processes and devices of this kind have been known for some time in the production of paper sheet. The disadvantage of the devices known is that either the contact pressure of the horizontal reel on the reel drum is such that the horizontal reel is driven by the force generated by friction, as shown by U.S. Pat. No. 5,611,500 A (Smith) or U.S. Pat. No. 5,845,868 A (Klerelid et al.), or a separate drive is provided for the horizontal reel, as in DE 197 48 995 A1 (Voith), where the pressing force cannot be set exactly because there are too many points where non-calculable losses arise, e.g. due to friction. The pressure pre-set at the contact pressure cylinders thus does not define the actual pressing force between reel drum and horizontal reel. Low pressing force is desirable in particular for tissue with a high volume in order to avoid destroying the high volume again with the contact pressure. In the conventional devices known, however, the pressing force can only be set imprecisely and the losses due to friction in the mechanical parts already exceed the required contact pressure, thus it is impossible to control the pressing force exactly.
SUMMARY OF THE INVENTION
The aim of the invention is to propose a process and a device that are easy to control during the winding process, even at low contact pressures.
The invention is thus characterized by the pressing force in the nip between the horizontal reel (core shaft) and reel drum being measured without any losses. Since the measurement is taken without any losses, the contact pressure can always be determined exactly and adjusted continuously.
An advantageous further development of the invention is characterized by the reading measured for the pressing force being used to control the pressing force at a desired level. Thus, it is also possible to set a low pressing force.
An advantageous configuration of the invention is characterized by the pressing force and the regulating distance being controlled by a measuring system integrated into the pressure cylinders that generate the contact pressure.
A favorable further development of the invention is characterized by the pressing force at the reel drum being measured in the direction of the force. As a result, the influence of friction and any influence on the measurement reading by the unbalanced mass of the paper roll can be eliminated.
If the load-sensing device is pre-stressed, sustained contact is guaranteed between oscillating lever and load-sensing device.
If the pressing force is measured horizontally in an advantageous configuration of the invention, this guarantees that also any weight influences, which otherwise always have to be taken into account separately, are eliminated.
In a favorable further development of the invention, a pre-set pressing force in the nip is transferred via the paper roll to the reel drum by the hydraulic cylinders for the secondary arms, while the force applied by the hydraulic cylinders can be adapted continuously on the basis of the measurement readings from the load-sensing device and the pressing force in the nip can preferably be maintained at a constant level. As a result, it is possible to achieve a low pressing force and, in consequence thereof, maintain the volume, particularly with high-volume tissue paper.
The invention also refers to a device for implementing the process, with a reel drum and a horizontal reel, characterized by load-sensing devices being provided for measuring the nip force without losses. Since the measurement is taken without any losses, the contact pressure can always be determined exactly and continuously adjusted, even with low contact pressures.
A favorable further development of the invention is characterized by the horizontal reel being supported on load-sensing devices, preferably throughout the entire reeling process. As a result, it is possible to measure the contact pressure directly and without any losses, while guaranteeing uniform paper quality right through the entire reeling process.
An advantageous further development of the invention is characterized by the load-sensing devices being provided in a horizontally adjustable holding device. In this way, it is possible to guarantee a constant force direction and simple transfer of the (controlled) pressing force.
An advantageous configuration of the invention is characterized by the horizontally adjustable holding device being provided with support rollers that run in guide units, where the guide units are sealed off by a vertically arranged moving belt. This ensures safe and low-friction adjusting, which permits the contact force to be adapted precisely, even at low values.
A favorable further development of the invention is characterized by the endless belt being made of woven fabric, synthetic material or steel. In this way, the most favorable solution can be sought in each case depending on the requirements and environment.
An advantageous further development of the invention is characterized by the vertically arranged moving belt being a continuous loop running round two rolls provided at the ends of the guide units. This arrangement provides a frictionless seal.
A favorable configuration of the invention is characterized by the deflection rolls having trapezoidal grooves to guide the belt, with the endless-woven belt at least having a trapezoidal profile that meshes into the trapezoidal grooves in the deflection rolls. This permits very good lateral belt guiding, where there can be no friction losses and the belt cannot run off track to the side.
A favorable further development of the invention is characterized by the reel drum being supported on vertical oscillating levers and a load-sensing device being inserted between the oscillating levers and a fixed counterpart. In this way, the influence of friction and any influence on the measurement reading by the unbalanced mass of the paper roll can be eliminated.
If the oscillating levers have tensioning elements that press these levers against the load-sensing device, sustained contact can be guaranteed between oscillating lever and load-sensing device. This also guarantees a continuous signal for a control device.
Here the tensioning elements can be mechanical with, for example, springs, or hydraulic or pneumatic with, for example, cylinders.
If the load-sensing device is mounted firmly in horizontal direction in the horizontal plane of the reel drum axis, this guarantees that also any weight influences, which otherwise always have to be taken into account separately, are eliminated.
With all of these measures, it is possible to guarantee exact measurements and maintain the contact pressure at a constant level at virtually any stage of the reeling process.
By inserting the load-sensing device at the fixed reel drum, exact measuring is always guaranteed, even if a roll (horizontal reel) is changed. This precision is not ensured in other known systems due to the time factor pressure during roll change, which often results in inexact work, and due to the resulting additional, non-calculable friction influence.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in examples and referring to the drawings, where
FIG. 1 shows a plant according to the invention,
FIG. 2 shows a sectional view taken along the line II—II in FIG. 1,
FIG. 3 contains an extract from FIG. 1,
FIG. 4 is a sectional view taken along the line IV—IV in FIG. 1,
FIG. 5 is a sectional view taken along the line V—V in FIG. 4,
FIG. 6 is a sectional view taken along the line VI—VI in FIG. 4,
FIG. 7 is an extract as encircled in VII in FIG. 6, and
FIG. 8 is an extract from a variant of the invention similar to FIG. 3 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The action of the device will now be described with the help of FIG. 1 . The core shaft (horizontal reel) 1 is placed in the primary arm 3 using a lowering device 2 and clamped in place hydraulically in a vertical position above the reel drum 4 . On the front side, FS, there is a gear motor 6 installed on a mounting plate and which is movable in axial direction. This motor is coupled to the core shaft 1 to bring the shaft up to machine speed.
A swivelling device 7 now turns the primary arm 3 round the axle of the reel drum 4 until the core shaft 1 is resting on the drum. During this process the core shaft 1 takes hold of the paper web P over its entire width with the aid of a suitable device and begins winding it on, thus increasing its diameter. The pressing force needed between the core shaft 1 and the reel drum 4 is applied and controlled via hydraulic cylinders 8 , which are fitted with a load-sensing device. Here, compensation of the weight of the core shaft 1 is also taken into account. The primary arm 3 is now swivelled further round the axis of the reel drum 4 until the core shaft 1 reaches a horizontal position. At the same time, the thickness of the paper roll increases continuously up to a maximum of 350 mm. During this process, the outer part of the primary arm 3 moves outwards telescopically. This arm runs on roller bearings 9 in order to keep the influence of friction on the nip force as low as possible. The paper roll is placed on a horizontally movable holding device 11 and clamped in.
FIG. 2 shows a sectional view taken along the line II—II in FIG. 1 . The holding device 11 comprises a receiving part 12 with two hydraulically operated clamping levers 13 , 14 and rests on a load-sensing device 16 , which again is mounted on the movable part 17 . The entire unit is also referred to as the secondary arm 10 . On the rear side TS, a gear motor 18 that is movable in axial direction is connected to the holding device 11 . As soon as the paper roll is horizontal, this drive 18 on the rear side TS is connected to the core shaft 1 and the drive 6 in the primary arm 3 is disconnected. In the further winding process the horizontal nip force (pressing force between horizontal reel 1 and reel drum 4 ) is generated via the secondary arm 10 with one hydraulic cylinder 19 on both the front side FS and rear side TS and controlled using a load-sensing device.
As the winding process continues in the secondary arm 10 , the next core shaft 1 is prepared in the primary arm 3 . As soon as the paper reel has obtained the desired size, it is pulled away from the reel drum 4 , the new core shaft 1 in the primary arm 3 is placed in the initial winding position on the reel drum 4 and the full width of the paper web P is now wound onto this new core shaft. When the finished paper roll has been ejected from the secondary arm 10 , this arm moves back to the reel drum 4 and then receives the new core shaft 1 from the primary arm 3 . The load-sensing devices 16 are designed such that they only measure the horizontal forces actually applied in the nip between the horizontal reel 1 and the reel drum 4 . Vertical components from the drives or from the changing own weight of the paper roll do not influence the values measured. The measured value signals recorded control the movement of the two hydraulic cylinders 19 in order to ensure that the secondary arms 10 are running absolutely parallel on the front FS and rear TS sides, and to guarantee a pre-selected nip force progression (constant or changing) through the entire winding process. The moving part 17 of the secondary arm 10 is supported on horizontal rollers 21 , which in turn run in guide units 26 in order to keep the influence of friction low here as well.
FIG. 3 now shows an extract from FIG. 1, showing the secondary arm 10 . Here it is possible to make out reel drum 4 and core shaft 1 with a partially wound paper roll. The pressing force A can be measured via load-sensing device 16 without losses and regardless of the position because there are no intermediate elements to cause losses. During the winding process, the movable part 17 of the secondary arm 10 is displaced by the hydraulic cylinders 19 in such a way that the pressing force A of the core shaft 1 acting on the reel drum 4 is always the same. The respective position of the secondary arm 10 is recorded here by measuring systems integrated into the cylinders 19 .
In order to avoid destroying the volume of the paper web P, very low pressing forces (down to a minimum of approx. 0.1 N/mm) are applied. The movable part 17 can be displaced with very low friction losses using the support rollers 21 .
These support rollers 21 are protected against dirt accumulations by a special device, which is shown in FIG. 4 (sectional view taken along the line IV—IV in FIG. 1 ). It consists of two deflection rolls 22 per guide unit 26 (8 deflection rolls in total for one plant), where one roll 22 can be tensioned. An endless woven belt 23 made of fabric, plastic or steel runs round the deflection rolls 22 . The support rollers 21 are secured to this belt 23 , however only one support roller 21 is shown here as an example.
FIG. 5 now shows a sectional view taken along the line V—V in FIG. 4, where the structure of the support rollers 21 is visible. The support rollers 21 run here on rails 27 . The surfaces 28 of the guide unit 26 are visible on the top and underside. This illustration also shows the endless woven belt 23 , to which the support rollers 21 are attached and which also moves along close to the wall surfaces 28 of the guide unit 26 on the other side.
FIG. 6 shows a sectional view taken along the line VI—VI in FIG. 4, which runs through a deflection roll 22 . The deflection rolls 22 have two trapezoidal grooves, for example, with two trapezoidal guide profiles 24 also being provided on the endless woven belt 23 , for example, which mesh into the grooves in the deflection rolls 22 and thus, prevent the belt from running off track to the side. The number of grooves may vary depending on the belt width.
FIG. 7 shows an extract VII from FIG. 6 . This illustration clearly shows lateral slots 25 in the wall 28 of the guide unit 26 , which are used to guide the belts 23 and as seals. In addition, the void 29 created by this device is protected against dust entering by the constant supply of compressed air blown in.
FIG. 8 shows the bearing assembly and load sensing in detail for a further variant of the invention. The reel drum 4 is supported on vertical swivelling levers 30 which are pivoted around bolts 31 . The load-sensing devices 32 are clamped in the horizontal plane of the reel drum 4 between the swivelling levers 30 and a fixed counterpart 33 , where the swivelling levers 30 are provided with tensioning elements 34 , which are operated either mechanically (e.g. springs), hydraulically or pneumatically (cylinders) and which always press against the load-sensing device. After the swivelling levers 30 have been tensioned, the load-sensing devices 32 are calibrated to nip force 0. After this, a pre-selected nip force is transferred via the paper roll to the reel drum 4 by the hydraulic cylinders (or pneumatic cylinders ( 19 )) of the secondary arms 10 . This force is measured by the load-sensing devices 32 and the measuring result used to control the hydraulic cylinders 19 .
This arrangement avoids any distortion of the measuring results due to the influence of friction, as is caused, for example, by cylinder seals or lateral friction due to the bearing housings rolling on rails. In addition, the unbalanced mass of the paper roll has no influence whatsoever on the measuring results, which otherwise is unavoidable if the horizontal reel is supported directly on measuring devices. Thus, the nip force can be measured and controlled very well and very accurately, even at very low contact pressures.
It should be appreciated that the control system 35 preferably includes two circuits 36 , 37 . The first circuit 36 connects the sensing device in the primary arm 3 with the respective pressure cylinders) 8 . The second circuit 37 connects the sensing device 16 in the secondary arm 10 with the pressure cylinder(s) 19 . Since the pressure force should be constant also between the primary and secondary arms 3 , 10 , both circuits 36 , 37 are preferably connected in the same control system 35 .
The invention is not limited to the examples shown. In addition to hydraulic cylinders, it is also possible to use, for example, pneumatic cylinders. | A process for continuous reeling of a pulp sheet, particularly a paper sheet, where the sheet runs over a reel drum and is later wound on a winding unit. The pressing force in the nip between the horizontal reel and the reel drum is measured without any losses. | 1 |
BACKGROUND
[0001] 1. Field of the Disclosure
[0002] This application generally relates to printing, and in particular, eliminating banding in semi-conductive magnetic brush developed images.
[0003] 2. Description of Related Art
[0004] Banding in printing systems has been and will continue to be an engineering challenge in xerographic marking engines based on semi-conductive magnetic brush (SCMB) development as shown, for example, in U.S. Pat. Nos. 5,539,505 and 6,285,837 B1. Image banding is an image quality defect that consists of halftone density variation in the process direction and manifests itself as light and dark bands in the cross-process direction. Banding is largely due to fluctuations in the photoreceptor (PR) drum to magnetic roll spacing resulting from photoreceptor and magnetic roll run-out. Mechanical variations in the development nip from photoreceptor and/or magnetic roll run-out can modulate the developer nip density (mass on roll) and hence developability resulting in banding. Banding is not always apparent at time-zero, but may manifest itself as the developer ages. Hence, other material state factors, such as: toner concentration/triboelectricity; toner age; and possibly material processing and flow properties. Material state factors may magnify the effect of even small initially acceptable variations in photoreceptor drum to magnetic roll spacing although they are not well understood.
[0005] Consequently, banding has been a very difficult problem to overcome and a method is needed to compensate for this effect other than costly mechanical countermeasures involving tightening of parts tolerances.
BRIEF SUMMARY
[0006] Accordingly, disclosed is an electronic development compensation method which is broadly applicable to SCMB development and comprises actively correcting for mechanical development errors by modulating the magnetic roll DC bias. Initially, the magnetic roll AC current is measured and filtered. Then, the low pass filtered current signal is amplified and AC coupled into a magnetic DC power supply error amplifier. A feedback circuit generates a time varying correction voltage that is applied to the DC bias on the developer power supply in phase with the AC current variation. All of these steps are accomplished in real-time with simple analog electronics.
[0007] The disclosed system may be operated by and controlled by appropriate operation of conventional control systems. It is well known and preferable to program and execute imaging, printing, paper handling, and other control functions and logic with software instructions for conventional or general purpose microprocessors, as taught by numerous prior patents and commercial products. Such programming or software may, of course, vary depending on the particular functions, software type, and microprocessor or other computer system utilized, but will be available to, or readily programmable without undue experimentation from, functional descriptions, such as, those provided herein, and/or prior knowledge of functions which are conventional, together with general knowledge in the software of computer arts. Alternatively, any disclosed control system or method may be implemented partially or fully in hardware, using standard logic circuits or single chip VLSI designs.
[0008] The term ‘printer’ or ‘reproduction apparatus’ as used herein broadly encompasses various printers, copiers or multifunction machines or systems, xerographic or otherwise, unless otherwise defined in a claim. The term ‘sheet’ herein refers to any flimsy physical sheet or paper, plastic, media, or other useable physical substrate for printing images thereon, whether precut or initially web fed.
[0009] As to specific components of the subject apparatus or methods, it will be appreciated that, as normally the case, some such components are known per se' in other apparatus or applications, which may be additionally or alternatively used herein, including those from art cited herein. For example, it will be appreciated by respective engineers and others that many of the particular components mountings, component actuations, or component drive systems illustrated herein are merely exemplary, and that the same novel motions and functions can be provided by many other known or readily available alternatives. All cited references, and their references, are incorporated by reference herein where appropriate for teachings of additional or alternative details, features, and/or technical background. What is well known to those skilled in the art need not be described herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Various of the above-mentioned and further features and advantages will be apparent to those skilled in the art from the specific apparatus and its operation or methods described in the example(s) below, and the claims. Thus, they will be better understood from this description of these specific embodiment(s), including the drawing figures (which are approximately to scale) wherein:
[0011] FIG. 1 shows a printer in accordance with an embodiment;
[0012] FIG. 2 is a chart showing magnetic roll AC current after full wave rectification and low pass filtering at 500 Hz;
[0013] FIG. 3 is a chart showing the FFT of the AC current in FIG. 2 ;
[0014] FIG. 4 shows scanned images of black halftones before and after electronic correction applied to DC developer voltage;
[0015] FIG. 5 shows banding FFT print scans; and
[0016] FIG. 6 shows an exemplary electronic development compensation method in accordance with an embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] While the disclosure will be described hereinafter in connection with a preferred embodiment thereof, it will be understood that limiting the disclosure to that embodiment is not intended. On the contrary, it is intended to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the disclosure as defined by the appended claims.
[0018] For a general understanding of the features of the disclosure, reference is made to the drawings. In the drawings, like reference numerals have been used throughout to identify identical elements.
[0019] FIG. 1 shows a schematic illustration of a printer 100 , in accordance with an embodiment. The printer 100 generally includes one or more sources of printable substrate media that are operatively connected to a printing engine 104 , and output path 106 and finisher 108 . As illustrated, the print engine 104 may be a multi-color engine having a plurality of imaging/development (SCMB) systems 110 that are suitable for producing individual color images. A stacker device 112 may also be provided as known in the art.
[0020] The print engine 104 may mark xerographically; however, it will be appreciated that other marking technologies may be used, for example by ink-jet marking, ionographically marking or the like. In one implementation, the printer 100 may be a Xerox Corporation DC8000™ Digital Press. For example, the print engine 104 may render toner images of input image data on a photoreceptor 114 , where the photoreceptor 114 then transfers the images to a substrate.
[0021] A display device 120 may be provided to enable the user to control various aspects of the printing system 100 , in accordance with the embodiments disclosed therein. The display device 120 may include a cathode ray tube, liquid crustal display, plasma, or other display device.
[0022] AC biases are employed in the SCMB development systems 110 in order to control developer conductivity and improve image quality (i.e., background). In accordance with the present disclosure, each of the developer systems include a developer nip positioned between a charge retentive substrate or photoreceptor 114 and a magnetic roll (not shown) and a real-time measurement of the AC current flowing through the development nip during a print cycle at the AC bias set-points (Vpp, frequency, duty cycle). In an ideal development nip, the AC current would be constant because the photoreceptor/magnetic roll spacing is constant. In real systems, the photoreceptor/magnetic roll spacing varies periodically because of photoreceptor and magnetic roll run-out and imperfect centering of the drives with respect to the center of the photoreceptor and magnetic roll. Envisioning the development nip, the AC (capacitive) current peaks when the photoreceptor/magnetic roll spacing is at a minimum and vice versa. Hence, the AC current follows the periodic variations in photoreceptor/magnetic roll spacing. Similarly, developability follows the variation in photoreceptor/magnetic roll spacing. Whether or not the AC current and developability are perfectly correlated is not known, however, experience has taught that the correlation is good enough that the AC current variations are useful for applying a correction to the DC magnetic bias to substantially mitigate banding. A magnetic bias applied to the developer stations at 110 can be used as a real-time “probe” of development nip density and/or mechanical errors. This mechanical error is actively corrected by modulating the magnetic roll DC bias.
[0023] In practice, the magnetic roll AC current on the developer bias line was measured in real-time during a print cycle as follows. The magnetic roll AC current was rectified through a full wave bridge and passed though an analog opto-coupler in order to measure the magnitude of the magnetic roll AC current. The latter signal was then low pass filtered to 100 Hz. An example of the latter signal is shown in FIG. 2 . The lower curve represents the AC current taken at 15k developer print life during a test of Fuji Xerox FC2 toner in a Xerox DC8000™ printer, while the upper curve shows the results taken at 40K into the test. Banding was not observed at 15K, but was observed at 40K. Thus, the current measurement is capable of discriminating the banding performance of the machine.
[0024] The low pass filtered current signal exemplified in FIG. 2 was then amplified and AC coupled into the magnetic DC power supply error amplifier. The AC couple was in the DC correction, so as to not add a DC offset to the DC bias. A feedback circuit generates a time varying correction voltage that is applied to the DC bias on the developer power supply in phase with the AC current variation. In one test, where the nominal DC development voltage was 544V the correction voltages needed to cancel the banding was about 5Vp-p. The magnetic DC supply was measured to have a frequency response up to 50 Hz which is more than adequate for this and most applications since most corrections occur at less than 10 Hz.
[0025] The frequency components of the AC current waveforms shown in FIG. 2 are presented in FIG. 3 . The fundamental and double of both the photoreceptor and magnetic roll rotational frequencies are seen to be the main components of the AC current variation and no components above 13 Hz were found in the test.
[0026] The method detailed hereinbefore was used to actively correct or null out the banding frequency components below 50 Hz. FIG. 4 shows a digital scan of the corrected and uncorrected prints side by side indicating visually the magnitude of the correction achieved. FIG. 5 shows the banding FFT of the prints of FIG. 3 . The FFT shows that the photoreceptor double and magnetic roll banding frequencies are eliminated from the halftones.
[0027] In recapitulation, an exemplary electronic development compensation method to actively correct or null out the banding frequency components in real-time below 50 Hz in xerographic marking engines based on SCMB development is shown in FIG. 6 as 200 and includes measuring the magnitude of the magnetic roll AC current in step 210 . Next, in step 220 , the signal is low pass filtered. Continuing to step 230 , appropriate correction amplification is applied to the signal. In step 240 , the signal is used to modulate magnetic roll DC power supply in phase with the AC current variation in step 210 . These steps are performed in real-time during a print cycle.
[0028] The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others. Unless specifically recited in a claim, steps or components of claims should not be implied or imported from the specification or any other claims as to any particular order, number, position, size, shape, angle, color, or material. | An electronic development compensation method which is broadly applicable to SCMB development includes controlling image banding by actively correcting for mechanical development errors by modulating DC bias to a magnetic brush. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to a process for the indigo dyeing of yarns in skeins or hanks.
As is known, the indigo dyeing of yarns is generally performed by means of so-called open width dyeing plants and so-called rope yarn plants.
In practice, open width plants use reels of yarn on which a large number of yarns, generally 350 to 400, is arranged; the yarns are arranged side by side and are passed in succession through the dyeing baths and rewound at the opposite end on reels in which the yarns are again arranged side by side.
In rope dyeing plants, dyeing is performed on a series of so-called ropes; each rope is constituted by a large number of yarns, generally 350 to 400, which are arranged side by side so as to define in practice a rope; said series is dyed by passing it in succession in a certain number of dyeing vats and, after the drying step, is placed in containers (one container per rope); the containers are then subjected to the separation of the yarns in order to arrange said yarns on reels (one container per reel) in which the yarns are arranged side by side.
This type of dyeing, which produces reels with a large number of yarns arranged side by side, is certainly useful if the weaving of fabrics is performed; in such weaving it can be useful to have the various yarns arranged side by side and wound on the same reel.
However, this arrangement does not allow to use the yarns in knitting machines, since it is necessary to have the yarn available on a spool.
Attempts made so far to dye the yarn arranged in skeins have not yielded satisfactory results, since the bath which is used for dyeing in skeins undergoes rapid degradation and change of characteristics, so that the dyeing does not have uniformity characteristics on the yarn.
Other known solutions, which provide for execution during the reeling of the yarn in ropes, by means of the separation of the yarns into groups of yarns which can then be subjected to a subsequent spooling step, are considerably complicated, since they require a long series of operations.
SUMMARY OF THE INVENTION
The aim of the invention is indeed to solve the above described problems by providing a process for the indigo dyeing of yarns in hanks or skeins which allows to perform dyeing of the yarn directly while it is arranged in skeins, without however being subject to the variations typical of the dyeing bath, which have led to unsatisfactory results with conventional methods.
Within the scope of the above aim, a particular object of the invention is to provide a process for the indigo dyeing of yarns in skeins which is particularly suitable for the obtainment of dyed yarns to be used in knitting, since passage from the single skein to the spool is extremely practical and easy.
Another object of the present invention is to provide a process which, by virtue of its peculiar characteristics of execution, is capable of giving the greatest assurances of reliability and safety in use.
Not least object of the present invention is to provide a process which can be obtained with a succession of easy steps, at least partially using conventional indigo dyeing elements.
This aim, these objects and others which will become apparent hereinafter are achieved by a process for the indigo dyeing of yarns in skeins, according to the invention, characterized in that it consists in placing a skein of yarn on at least two spaced rollers, in at least partially impregnating said skein in an indigo dyeing bath drawn continuously from a main indigo dyeing bath of a plant for the continuous dyeing of yarns in ropes or bands, in exposing the impregnated part to air for its oxidation, in alternately repeating impregnation and oxidation for a preset number of times which is a function of the color intensity to be obtained, in washing the skein to remove the residue of dye which has not been fixed on the fiber and in drying the skein.
BRIEF DESCRIPTION OF THE DRAWINGS
Further characteristics and advantages will become apparent from the description of a preferred but not exclusive embodiment of a process for the indigo dyeing of yarns in skeins, illustrated only by way of non-limitative example with the aid of the accompanying drawings, wherein:
FIG. 1 is a schematic view of a plant for the continuous indigo dyeing of yarns in ropes or bands;
FIG. 2 is a schematic view of the plant connected to a unit for the indigo dyeing of yarns in skeins;
FIG. 3 is a schematic perspective view of the unit for the dyeing of the yarn in skeins; and
FIG. 4 is a schematic front elevational view of the unit for the dyeing of yarns in skeins, during the washing step.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the above figures, the conventional plant for the indigo dyeing of yarns in ropes or bands has a plurality of vats 1, generally six to eight, which have a capacity of approximately 3,000 liters each.
The yarn, designated by the reference numeral 2, is subjected in succession, in a per se known manner, to impregnation steps which are followed by oxidation steps which alternate continuously for a number of times which is equal to the number of vats in use.
The cycles related to dyeing provide for the feeding of the dye intensification baths, the homogenation of the dyeing bath and the absorption of the dyeing bath into the yarn.
Essentially, the intensification baths provide for the feeding of a first bath, known as main bath, which contains water, indigo, sulphinate and soda, and a second bath, known as reduction bath, which contains only water, sulphinate and soda.
Essentially, one liter of the intensification baths is fed for every kilogram of yarn which enters the machine.
In order to keep the bath feeds constant in any case, it is indispensable to operate by excess, allowing the tapping of the bath in order to keep its homogenation under control.
In order to obtain the homogenation of the bath as shown in FIG. 1, each vat is connected, at its bottom, to a return manifold 3 which, by means of a filter 4, is connected to a delivery pump 5 after which the feeds 6 and 7 merge; said feeds are constituted by said main bath and by the reduction bath; the bath, with its associated replenishments, is fed into a delivery duct 10 which is connected to the inside of the various vats 1, which are mutually interconnected so as to define in practice a communicating vessel.
The homogenation of the bath is obtained in this manner; said homogenation is also increased by the movement of the fabric, which is subjected to continuous ascending and descending passes which keep the bath of each individual vat in motion.
As previously mentioned, the feeds of the intensification baths are performed according to the amount of yarn to be dyed and according to the required color; all of the above is calculated in kg/h as regards the yarn, taking into account the speed of the dyeing line.
It should be stressed that the dosage of the feeds of the main bath and of the reduction bath is performed immediately after the delivery of the circulation pump, and this allows correct distribution in each individual vat, avoiding the forming of different situations of chemical equilibrium in the various regions of the dyeing bath.
The bath cannot be prepared beforehand, since it needs the intensification feeds, and the dyeing bath or main bath maintains, for the entire duration of the operation of the machine, its own distinct composition of soda, sulphinate and indigo, also by virtue of all the active recirculations.
When the machine stops, the feeds and the recirculations also stop, and the composition of the dyeing bath rapidly changes, mainly in its sulphinate component and also, to a lesser extent, in its soda component.
Due to these variations, it has been observed that the skein dyeing tested so far was unable to provide satisfactory results since it was not possible to keep the parameters constant and consequently obtain uniformity in the dyeing of the skein.
The invention has solved the problem by providing a process in which a skein dyeing unit is arranged and is in practice connected in parallel to a main indigo dyeing bath which arrives from a conventional plant for the continuous dyeing of yarns in ropes or bands.
In practical execution, the skein, designated by the reference numeral 20, is applied on two spaced rollers 21a and 2lb which can be moved mutually closer so as to allow the application of the skein.
The rollers are arranged at a tray 22 in which the dyeing bath is fed; said bath is drawn from the main bath of the continuous plant, as schematically shown in FIG. 1.
The dyeing bath for the dyeing unit for skein is fed continuously, so that a stabilized bath, with the correct parameters for the type of dyeing to be performed, is always available; this stability is ensured by the fact that the main bath is controlled as mentioned above.
Once the skein has been applied on the rollers, said skein is immersed in the skein dyeing bath, in practice by lifting the tray 22, so that the bath arrives at the axes of the rollers, so that half of the skein remains immersed.
One of the rollers, and specifically the roller designated by the reference numeral 21a, is a drive roller; once it is made to rotate, it creates a continuous movement of the skein, impregnating it, so that the skein is partially immersed in the dyeing bath and is then exposed to the air to oxidize the dye; the cycle is repeated for a preset number of times, according to the shade of color to be obtained.
Advantageously, the roller is rotated for a certain period of time, so as to obtain a movement of the skein in the bath which is in counter-current, and rotation is reversed for alternating periods of time so as to have parallel-flow immersion; this allows to keep a constantly uniform distribution in the bath, avoiding the forming of preferential regions of flow of dyeing liquid.
According to a non-limitative embodiment, a skein with a circumference of 1940 mm, a weight of 250 g, a length of yarn in the skein of approximately 6800 m and a skein width on the rollers of 200 mm is prepared using a 16-count yarn.
Three passes in counter-current with respect to the dyeing bath, alternated with two parallel-flow passes, are advantageously performed.
In practice, each pass, which lasts approximately one minute, is composed of 30 seconds of impregnation alternated with 30 seconds of oxidation.
Once alternated impregnation and oxidation have been performed, the skein is passed in air for approximately 1 minute so as to complete oxidation.
After these steps, the skein is subjected to conventional washing in warm and cold water to remove the residue of dye which has not fixed on the fiber, and then said skein is removed from the rollers and put to dry.
To the above it should also be added that a squeezer roller, designated by the reference numeral 30, is provided at the drive roller and has the purpose of removing the excess liquid from the yarn.
The dyeing bath which is used in the group of yarns arranged in a skein is drawn, as mentioned, from the main bath by means of the pump 31 and after the dyeing of the group arranged in a skein it is returned to the main bath by means of the pump 32, so as to always use a dyeing liquid which has uniform and stable characteristics.
It is considerably important to stress the fact that uniform skein dyeing is obtained since, by using in practice the main bath of a plant for continuous dyeing in bands or ropes, a bath which allows to maintain a correct and time-invariant chemical equilibrium is always available, preventing the occurrence of problems in color intensity, friction strength and risk of excessive penetration of dye into the fiber.
In practice, therefore, dyeing in skeins is possible since a closed circuit for the recirculation of the dyeing bath is provided; said recirculation occurs over a main bath which, in addition to being constituted by a large quantity, is always assuredly controlled and stabilized in a conventional manner.
From what has been described above, it can thus be seen that the invention achieves aim and objects, and in particular, the fact is stressed that skein dyeing with remarkable characteristics of stability and color uniformity is obtained, simplifying all the subsequent steps for the rewinding of the yarns, since a dyed yarn in skeins is directly available.
The invention thus conceived is susceptible to numerous modifications and variations, all of which are within the scope of the inventive concept.
All the details may furthermore be replaced with other technically equivalent elements. | Process for the indigo dyeing of yarns in skeins having the peculiarity that it consists in placing a skein of yarn on at least two spaced rollers, in at least partially impregnating the skein in an indigo dyeing bath drawn continuously from a main indigo dyeing bath of a plant for the continuous dyeing of yarns in ropes or bands, in exposing the impregnated part to air for its oxidation, in alternately repeating impregnation and oxidation for a preset number of times which is a function of the color intensity to be obtained, in washing the skein to remove the residue of dye which has not been fixed on the fiber and in drying the skein. | 3 |
FIELD OF THE INVENTION
[0001] The invention relates to rollers used in a coating apparatus. In particular the invention relates to apparatus used for coating one or more viscous coating compositions as a composite layer onto a continuously moving receiving surface, such as in the manufacture of photographic films, photographic papers, magnetic recording tapes or such like.
BACKGROUND OF THE INVENTION
[0002] In an apparatus designed for the production of coated webs of material, the web is conveyed through the machine by a series of rollers. As the web moves through the machine, the web entrains a layer of air termed a boundary layer. At each roller, as the web approaches, the boundary layer on the web face about to contact the roller is squeezed between the web and the roller. The increased pressure causes the web to lift off the roller, thereby causing a loss of traction and poor web steering. It is well known in the art that this problem is alleviated by forming a pattern in the roller surface such that the boundary layer of air can escape, thereby recovering good traction and conveyance. The pattern may take several forms: a random pattern (U.S. Pat. No. 4,426,757), a roller wound with spaced turnings of wire (U.S. Pat. No. 5,431,321; U.S. Pat. No. 4,427,166) or a groove pattern (U.S. Pat. No. 3,405,855).
[0003] Throughout the coating machine, individual rollers may be patterned differently, however a simple and well-known pattern that is often used is the groove pattern. This consists of a periodic series of grooves cut around the circumference of the roller where the period, depth and width of the grooves is determined by the requirements for speed of conveyance and by the web material that is being conveyed (U.S. Pat. No. 3,405,855). This groove pattern is easy to manufacture and is easy to clean should debris contaminate the grooves, and thus is particularly favoured.
[0004] It is well known in the art of coating that to improve the maximum obtainable coating speed before the onset of air entrainment, an electrostatic field may be applied at the coating point (for example, EP 390774; WO 89/05477; U.S. Pat. No. 5,609,923). In general, the web is supported by a roller at the coating point and this roller is referred to as the coating roller. It is also well known that the electrostatic field may be generated by either providing a charge on the web surfaces and grounding both the coating roller and the coating liquid (for example, EP 390774; U.S. Pat. No. 4,835,004; U.S. Pat. No. 5,122,386; U.S. Pat. No. 5,295,039; EP 0 530 752 A1), or by biasing the coating roller while maintaining the liquid at ground potential (for example, U.S. Pat. No. 3,335,026; U.S. Pat. No. 4,837,045; U.S. Pat. No. 4,864,460), or by a combination of both. In either case, a particular coating defect may arise whereby the roller pattern is transferred to the final coating (see U.S. Pat. No. 5,609,923 and U.S. patent application Ser. No. 09/212,462; filed Dec. 16, 1998 by Mark C. Zaretsky et al; entitled METHOD FOR USING A PATTERNED BACKING ROLLER FOR CURTAIN COATING A LIQUID COMPOSITION TO A WEB. This defect is herein described as electrostatic pattern transfer, however, for a grooved roller this defect is sometimes known as microgroove lines. It will be understood that the defect results in unusable product and therefore must be avoided. On certain web materials and under certain conditions therefore, an electrostatic field cannot be used to enhance coating speeds, and the coating machine must be run more slowly, so reducing productivity.
SUMMARY OF THE INVENTION
[0005] According to the present invention there is provided a roller for use in a coating machine, the roller comprising a metal core having an outer cover of dielectric material, the cover being provided with an engraved pattern, the core being provided with a second pattern having ridges under the engraved pattern in said cover and in register with the pattern in said cover, whereby an electrostatic field generated above a web supported on the roller may be made substantially uniform.
[0006] The roller design alleviates the problem of electrostatic pattern transfer, thereby expanding the applicability of electrostatic fields in the coating process.
[0007] The combination of the pattern cut in the dielectric cover and the pattern formed on the core is such that when a voltage is applied to the roller, or when a charge is applied to the web being coated, the field in the immediate vicinity of an earthed plane immediately above is substantially constant. Where the earthed plane is a liquid being coated onto the web, the fact that the field is substantially constant significantly reduces the electrostatic pattern transfer defect. In addition, the pattern cut in the dielectric cover acts in the usual way to provide an escape path for the boundary layer air carried along by the web.
[0008] For a better understanding of the present invention reference is made to the following drawings and detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] [0009] 15 FIG. 1 a is a schematic cross-sectional view, parallel to the roller axis, of the surface of a conventional roller;
[0010] [0010]FIG. 1 b is a perspective view of the roller of FIG. 1 a;
[0011] [0011]FIG. 1 c is a greatly enlarged section of the roller of FIG. 1 b as indicated by circle 1 c;
[0012] [0012]FIG. 2 is a schematic cross-sectional view, parallel to the roller axis, of the surface of a roller according to the invention;
[0013] [0013]FIG. 3 shows an electrode configuration that may be used for the purposes of optimising the design of a pattern; and
[0014] [0014]FIG. 4 is a graph showing coating non-uniformity against voltage applied to the coating roller for both a roller according to the invention and a conventional roller.
DETAILED DESCRIPTION OF THE INVENTION
[0015] [0015]FIG. 1 shows a cross-section of a conventional roller. Although the grooves shown are of circular section, alternative shapes, for example, rectangular, may be used.
[0016] Referring to FIG. 2, a metal core 1 is covered by a layer of dielectric material 2 . It will be understood that material of layer 2 should be chosen such that it has the appropriate properties for a coating roller: hardness, durability, machinability, stability, etc. In addition and for convenience, material 2 should have as low a relative permittivity as possible consistent with the other material property requirements. A pattern 3 , which may be grooves, is cut in the dielectric layer. For a grooved roller, dimension 5 is the groove period, 6 is the half-width of the groove and 7 is the depth of the groove. These dimensions are the same as for the conventional roller shown in FIG. 1 and are determined by the requirement for good ventilation between the web and the roller. Good ventilation allows good traction and conveyance. For the core 1 of the grooved roller, dimension 5 is also the period of the pattern on the core, 9 is the half width of the metal ridges and 8 is the depth of the dielectric layer. The depth 8 should be approximately equal to the relative permittivity of the layer multiplied by the dimension 7 . It should be noted that the patterns used for the roller and core shown in FIGS. b , 1 c and 2 are not unique and other patterns following the same general principles will also work. However, having chosen the pattern dimensions and shape for engraving the dielectric layer, the dimensions and pattern of the metal core will have optimum values. The required pattern for the metal core may be optimised by calculating the field strength variation at the surface of electrode of the model configuration illustrated in FIG. 3. FIG. 3 shows an electrode 12 separated by distance 10 from a web 13 of thickness 11 and relative permittivity e B . The dielectric roller cover 2 of relative permittivity e, has a groove of generalised shape cut in it (dimensions: d groove , d c =e. d groove , w 1 ′, and w 1 ) and is backed by the metal core 1 , again of generalised shape (dimensions: d r =(e−1). d groove , w 2 ′, and w 2 ). Such a calculation may be performed using one of several standard numerical techniques, for example, finite difference, finite element, etc. The shape of the groove and ridge in FIG. 3 can of course be further generalised and FIG. 3 should not be regarded as limiting the invention.
[0017] In applying this invention, since a dielectric web will necessarily be contacting a dielectric surface (the roller) there is the possibility that the surface of the roller will become charged. This possibility can be minimized by the use of ionizers, etc. Alternatively, the surface of the roller could be made very weakly conductive so as to bleed the charge away.
EXAMPLE
[0018] The new design has been tested in a coating roller and the effect on the coating non-uniformity assessed. The roller was constructed to have grooves of conventional design on one half and of the new design on the other. In this way, direct comparison of the efficacy of the design for otherwise identical coating conditions could be made. FIG. 4 shows the relationship between the severity of the non-uniformity seen in the coating and the voltage applied to the coating roller. The line joining the circles represents a roller having a conventional surface as shown in FIG. 1, and the line joining the squares represents the new surface having the composite structure as shown in FIG. 2.
[0019] In the experiment, a two-layer coating was made. The total flow rate of liquid per unit width was 1.22 cm 2 /s and the web speed was 75 cm 2 /s. The coating liquids were aqueous gelatine having a top layer low-shear viscosity of 65 mPas, a bottom layer low-shear viscosity of 120 mPas, and a bottom layer flow rate per unit width of 0.17 cm 2 /s. In addition, the bottom layer contained blue dye to enable measurement of the severity of the non-uniformity. The substrate was polyethylene teraphthalate precoated with a gelatine subbing layer. The dimensions of the microgrooves were 5=1.2 mm, 6=0.2 mm, 9=0.1 mm, 7=0.15 mm and 8=0.4 mm. These dimensions are approximate and were not fully optimised. The dielectric layer was made from an epoxy resin (RS Components stock number 199-1402) with relative permittivity e=2.69. It will be understood that the absolute magnitude of the coating non-uniformity will depend on the coating method used and the conditions employed. However, the relative magnitude of the non-uniformity between the conventional surface and the new surface of composite structure is dependent only on the roller design. It is clear from the results shown in FIG. 4 that the new surface design for the dimensions specified shows an approximately six-fold improvement over the conventional surface.
Parts List
[0020] [0020] 1 . Metal core
[0021] [0021] 2 . Dielectric cover
[0022] [0022] 3 . Engraved pattern on cover
[0023] [0023] 4 . Engraved pattern on core
[0024] [0024] 5 . Groove period
[0025] [0025] 6 . Half width of groove
[0026] [0026] 7 . Depth of groove
[0027] [0027] 8 . Depth of dielectric layer
[0028] [0028] 9 . Half width of metal ridges
[0029] [0029] 10 . Distance between electrode and web
[0030] [0030] 11 . Web thickness
[0031] [0031] 12 . Electrode | A roller for use in a coating machine comprises a metal core 1 having a dielectric cover 2. The cover is provided with an engraved pattern of ridges and grooves. The core is also provided with a pattern in register with the pattern in the cover such that an electrostatic field generated above a web supported on the roller may be made substantially uniform. | 1 |
This application is a division of application Ser. No. 07/752,206 filed Aug. 21, 1991 U.S. Pat. No. 5,310,356 which is a continuation-in-part of application Ser. No. 07/473,060, filed Jan. 31, 1990, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an ink, and a recording process using it. More particularly, it relates to a water-based ink capable of giving a black image improved in indoor color change resistance, and a recording process, in particular, ink-jet recording process, using the ink.
2. Related Background Art
Water-based inks comprising a water-soluble dye dissolved in a water-based medium have been hitherto used as inks used in fountain pens and felt pens and inks used for ink-jet recording. In these water-based inks, water-soluble organic solvents are commonly added so that pen points or ink ejection nozzles can be protected from being clogged with ink.
It is required for these conventional inks to give an image with a sufficient density, not to cause any clogging at pen points or nozzles, to have good drying properties on recording mediums, to cause less feathering, to have an excellent shelf stability, and, particularly in ink-jet recording systems utilizing heat energy, to have an excellent thermal fastness. It is also required for the image formed to have a satisfactory light-fastness and a water fastness.
Inks with various hues are also prepared from dyes with various hues. Of these, black inks, which are used in both monochromatic and full-color images, are most important inks. As dyes for these black inks, C.I. Food Black 2 has been mainly used taking account of various performances (see Japanese Patent Laid-open No. 59-93766 and No. 59-93768).
Among the various required performances, what is particularly important is the fastness of the images formed.
In regard to the fastness of images, hitherto mainly questioned is the color fading due to direct sunlight or every kind of illumination light. Such a problem of color-fading has been attempted to be settled by the selection of dyes having a superior light-fastness.
Recently, however, a problem of color changes of images has become important in addition to the above color fading. Namely, images formed by conventional inks have not only the problem of color fading but also the problem of color changes. The color changes refer to changes in hues with, however, less changes in density, and what is important in black inks particularly used in a largest quantity is a problem of the browning that black turns brown. In particular, in the instance of full-color images, this browning results in a great lowering of image quality.
The browning also occurs indoors without exposure to direct sunlight. The color change is also accelerated depending on the types of recording mediums on which images are formed, and the browning has been unavoidable in respect of the C.I. Food black 2 that has been hitherto widely used.
In particular, in such an instance of so-called coated papers having an ink-receiving layer containing a pigment and a binder on a substrate such as paper, for the purpose of improving the color-forming performance of ink and the image quality such as sharpness and resolution, the browning has seriously occured even with use of inks that have caused less problem of color change in the instance of plain papers. This problem has been unsettled by the mere selection of dyes having a superior lightfastness.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide an ink that can satisfy the performances commonly required as mentioned above and also may not cause browning even on the coated papers, and a recording process using this ink.
The above object can be achieved by the present invention as described below.
The present invention provides an ink, and a recording process using the ink, containing at least a dye and a liquid medium, wherein said dye is a dye of Formula (I): ##STR3## wherein R 1 and R 2 represent independently an alkyl group, an alkoxy group or an acetylamino group; R 3 represents --SO 3 M or a hydrogen atom; R 4 represents a hydrogen atom, --SO 3 M or --NHR 5 , where R 5 represents a hydrogen atom, a phenyl group that may have a substituent or a group of the formula ##STR4## where R 6 and R 7 represent independently a hydrogen atom, or --C 2 H 4 OH; M represents an alkali metal, an ammonium group or an organic ammonium group; and l, m and n represent independently an integer of 0 or 1.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1(a) and 1(b) are respectively a longitudinal sectional view and a cross-sectional view of the head part of an ink jet recording device;
FIG. 2 is a perspective view of the appearance of a multiple head which comprises the head shown in FIG. 1;
FIG. 3 is a perspective view of an example of an ink jet recording apparatus;
FIG. 4 is a longitudinal sectional view of an ink cartridge; and
FIG. 5 is a perspective view of an ink jet device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Use of the dyes of the above Formula (I) as the dye for the ink makes it possible to provide a black ink capable of giving an image that may not cause the indoor color changes, i.e., the browning, even when the coated papers are used.
In the recording process of the present invention, use of the above ink makes it possible to provide a black image which has less browning on the coated papers.
The present invention will be described below in greater detail by giving preferred embodiments.
Black dyes used in the present invention may all commonly comprise sodium salts of water-soluble groups such as a sulfonic acid group. In the present invention, however, they are not limited to the sodium salts, and the same effect can be obtained also when the counter ion thereof is potassium, lithium, ammonia, organic amine, or the like. Thus, the dyes containing any of these other counter ions are also included in the present invention. Examples of the dye represented by the above Formula (I) include the following dyes, but are by no means limited to these. ##STR5##
Among the above, particularly preferred are the compounds wherein R 1 and R 2 are selected from the group consisting of methyl, methoxy, ethoxy and acetyl amino; R 3 is --SO 3 M; R 4 is --SO 3 M or --NHR 5 where R 5 is a phenyl group that may have a substituent, or a group of the formula ##STR6##
The number of --SO 3 M in the molecule is preferably from 3 to 4, in consideration of the solubility into the liquid medium.
The dyes are exemplified in the above can be prepared following the syntheses of azo dyes known in the art. An example of the synthesis of the above No. 5 dye will be described below.
0.1 mol of H-acid is dispersed in 500 ml of water, to which 0.3 mol of hydrochloric acid is added, and then 0.1 mol of sodium nitrite dissolved in 50 ml of water is added at 0° to 5° C. to effect diazotization. In a mixed solution of 200 ml of water and 0.2 mol of hydrochloric acid, 0.1 mol of 5-acetylamino-o-anisidine is dissolved, and the above diazotized solution is added thereto at 5° to 10° C. The mixture is adjusted to pH 5 to 6 using sodium acetate, and then stirred for 2 hours. The temperature is raised to 60° C., followed by salting out with a common salt and the precipitate is filtered.
The cake is dissolved in 500 ml of water under weakly alkaline conditions, to which 0.3 mol of hydrochloric acid is added, following by ice cooling. To the resulting solution, 0.1 mol of sodium nitride dissolved in 50 ml of water is added at 0° to 5° C. to effect diazotization. 0.1 mol of 1-naphthylamine-7-sulfonic acid is dissolved in 300 ml of water, under weakly alkaline conditions, and the above diazotized solution is added in the resulting solution at 5° to 10° C., which is then adjusted to pH 5 to 6 using sodium acetate, and stirred for 3 hours, followed by salting out with a common salt, and then the precipitate is filtered.
The cake is dissolved in 600 ml of water under weakly alkaline conditions, to which 0.3 mol of hydrochloric acid is added, and then 0.1 mol of sodium nitrite dissolved in 50 ml of water is added at 0° to 5° C. to effect diazotization. In 300 ml of water, 0.1 mol of sodium 1-naphthylamine-8-sulfonate is dissolved, and the above diazotized solution is poured therein under ice cooling. The mixture is stirred for 6 hours at a pH of 5 to 6 and a temperature of 5° to 10° C. Salting out with a common salt is repeated several times to remove impurities. Thereafter, using a strongly acidic ion-exchange resin, the sulfonic acid group of the dye is converted to a free acid type (SO 3 H), followed by neutralization using monoethanolamine, and then desalting purification by the use of an ultrafiltration apparatus (manufactured by Saltrius Co.). The above No. 5 dye is thus obtained.
There are no particular limitations on the amount of the dye to be used in the ink of the present invention. In general, however, it may be an amount that holds from 0.1 to 15% by weight, preferably from 0.3 to 10% by weight, and more preferably from 0.5 to 6% by weight, based on the total weight of the ink.
The aqueous medium preferably used in the ink of the present invention is water, or a mixed solvent of water with a water-soluble organic solvent. Particularly preferably used is the mixed solvent of water with a water-soluble organic solvent, containing as the water-soluble organic solvent a polyhydric alcohol having the effect of preventing drying of an ink. As the water, it is preferred not to use commonly available water containing various ions, but to use deionized water.
The water-soluble organic solvent used by mixture with the water includes, for example, alkyl alcohols having 1 to 5 carbon atoms, such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tertbutyl alcohol, isobutyl alcohol, and n-pentanol; amides such as dimethylformamide and demethylacetamide; ketones or ketoalcohols such as acetone and diacetone; ethers such as tetrahydrofuran and dioxane; polyalkylene glycols such as polyethylene glycol and polypropylene glycol; alkylene glycols comprising an alkylene group having 2 to 6 carbon atoms, such as ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol, hexylene glycol, and diethylene glycol; glycerol; lower alkyl ethers of polyhydric alcohols, such as ethylene glycol monomethyl or monoethyl ether, diethylene glycol monomethyl or monoethyl ether, and triethylene glycol monomethyl or monoethyl ether; lower dialkyl ethers of polyhydric or diethyl ether and tetraethylene glycol dimethyl or diethyl ether; sulfolane; N-methyl-2-pyrrolidone; and 1,3-dimethyl-2-imidazolidinone.
Suitable solvents are selected from the organic solvents as described above and put into use. Particularly important from the view point of preventing the clogging with ink is glycerol or a polyethylene oxide with a degree of polymerization of 2 to 6. Taking account of the image density and ejection stability, preferred are nitrogen-containing cyclic compounds, such as N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone and so on, or ether compounds of polyalkylene oxides, such as diethylene glycol monomethyl or monoethyl ether, triethylene glycol monomethyl or monoethyl ether and so on. Further taking account of the frequency response, it is preferred to use lower alcohols, such as ethyl alcohol, n-propyl alcohol, isopropyl alcohol and so on, or surface active agents. Hence, the solvent composition preferred in the present invention contains the components as described above in addition to the water.
The above water-soluble organic solvent may be contained in the ink in an amount of generally from 2 to 80% by weight, preferably from 3 to 70% by weight, and more preferably from 4 to 60% by weight, based on the total weight of the ink.
The water to be used may be in a proportion such that it holds not less than 35% by weight, and preferably not less than 45% by weight, of the whole ink. An excessively small amount of water may result in a large quantity of a low-volatile organic solvent remaining in the image formed, which may cause undesirably problems of migration of dyes, feathering of images, and so forth.
In addition to the above components, the ink of the present invention may also optionally contain pH adjustors, viscosity modifiers, surface tension modifiers, and so forth. The pH adjustors used in the above ink include, for example, all sorts of organic amines such as diethanolamine and triethanolamine, inorganic alkali agents such as hydroxides of alkali metals as exemplified by sodium hydroxides, lithium hydroxide and potassium hydroxide, organic acid salts such as lithium acetate, organic acids, and mineral acids.
The ink of the present invention, as described above, may preferably have physical properties of a viscosity at 25° C., of from 1 to 20 cP, and preferably from 1 to 15 cP; a surface tension of not less than 30 dyne/cm, and preferably not less than 40 dyne/cm; and a pH of approximately from 4 to 10.
The recording process of the present invention is characterized by using the ink described above, and there are no particular limitations on a recording system and a recording medium. In particular, however, particularly effective are the methods in which an ink-jet system is used as the recording system and a coated paper is used as the recording medium.
The ink-jet system may include any conventionally known systems, without any particular limitations. In the present invention, however, the system as disclosed in Japanese Patent Laid-Open No. 54-59936 is particularly useful, which is a system in which heat energy is acted on an ink to cause therein an abrupt volume change and the ink is ejected from a nozzle by the force of action attributable to this change in state.
Namely, in this system, conventional inks have tended to cause deposition of foreign matters on a heating head to cause the trouble of no ejection of ink. However, the ink of the present invention, which does not cause such deposition of foreign matters, is feasible for stable recording.
As the recording medium used in the present invention, any recording medium can be used such as commonly available plain papers such as wood free papers, coated papers, and plastic films for OHP. A remarkable effect can be exhibited particularly when the coated papers are used.
The coated papers refer to those which are comprised of wood free paper used as a substrate, and provided on the surface thereof an ink-receiving layer comprising a pigment and a binder, aiming at improvements in the color-forming properties attributable to ink, sharpness, and dot shapes.
In the case of these coated papers, those which employ as the pigment a fine pigment such as synthetic silica having a BET specific surface area of from 35 to 650 m 2 /g can provide images having excellent color-forming properties and sharpness. When conventional inks are used, however, the image formed particularly with a black ink may seriously cause the problem of browning with lapse of time, though its theoretical reasons are unknown, and great problems are also caused in not only black monochromatic images but also full-color images. Similar problems are also caused in recording mediums comprised of, like these coated papers, a thin layer comprising a pigment and a binder on a paper substrate, where fibers of the paper that constitute the substrate are present in this layer in a mixed state.
It has been found that use of the ink of the present invention does not cause the problems of browning as discussed above even when monochromatic images or full-color images are formed on coated papers as mentioned above. Thus, the process according to the present invention can provide recorded images that may not bring about any indoor color change for a long period of time, when using not only the coated papers employing the pigment having a BET specific surface area of from 35 to 650 m 2 /g, but also coated papers employing a pigment having a BET specific surface area smaller than that, and also plain papers and any other recording mediums.
The recording processes according to the ink-jet system and the various recording mediums are known in the art, or proposed in variety by the present applicants and others. These recording processes and the recording mediums can all be used in the present invention as they are.
The ink of the present invention is preferably used in the ink jet recording method in which ink droplets are discharged by employing thermal energy. However, the recording solution can also be used for general writing utensils.
An example of the recording apparatus which is preferable for recording by using the ink of the present invention is an apparatus in which ink droplets are produced by applying heat energy to the ink in the chamber of a recording head in correspondence with a recording signal.
FIGS. 1(a), 1(b) and 2 show examples of the structure of a head, which is a principal part of an ink jet recording apparatus.
In the drawings, a head 13 is formed by bonding a glass, ceramic or plastic plate, which has a groove 14 for allowing ink to pass therethrough, and a heating head 15 used for heat-sensitive recording. Although a thin film head is shown in the drawings, the head is not limited to such an embodiment. The heating head 15 comprises a protective film 16 made of silicon oxide or the like, aluminum electrodes 17-1, 17-2, a heating resistor layer 18 made of nichrome or the like, a heat-accumulating layer 19 and a substrate 20 made of aluminum or the like and having good heat radiation properties.
Ink 21 reaches a discharging orifice (micropore) 22 and forms a meniscus 23 at pressure P.
When an electrical signal is applied to the electrodes 17-1, 17-2, a region off the heating head 15, which is denoted by n, rapidly generates heat so as to generate air bubbles in the ink 21 which contacts with the region. The meniscus 23 is projected by the pressure generated, and the ink 21 is discharged as a jet of ink droplets 24 from the orifice 22. The droplets 24 are propelled toward a recording material 25. FIG. 2 shows a multiple head comprising a plurality of the heads shown in FIG. 1(a) which are arranged in parallel. The multi-head is formed by bonding a glass plate 27 having a plurality of grooves 26 and a heating head 28, which is the same as that shown in FIG. 1(a).
FIG. 1(a) is a sectional view taken along the ink flow channel of the ink, and FIG. 1(b) is a sectional view taken along the line A-B in FIG. 1(a).
FIG. 3 shows an example of an ink jet recording apparatus in which the head shown in FIG. 1 is incorporated.
In FIG. 3, reference numeral 61 denotes a blade serving as a wiping member in the form of a cantilever in which one end is a fixed end held by a blade holding member. The blade 61 is disposed at a position adjacent to a region of recording by a recording head. In this example, the blade 61 is held in a position in which it projects in the path of the movement of the recording head. Reference numeral 62 denotes a cap which is disposed at a home position adjacent to the blade 61 and which is moved in the direction vertical to the moving direction of the recording head so as to contact with the orifice surface for the purpose of capping. Reference numeral 63 denotes an ink absorber which is disposed at a position adjacent to the blade 61 and which is held in a position in which it projects in the path of the movement of the recording head in the same way as the blade 61. The blade 61, the cap 62 and the absorber 63 forms a discharging recovery part 64. Moisture and dust on the ink orifice surface are removed by the blade 61 and the absorber 63.
Reference numeral 65 denotes the ink jet device which has a means for generating discharging energy so as to record an image by discharging the ink to the recording material opposite to the orifice surface having orifices. Reference numeral 66 denotes a carriage for moving the ink jet device 65 which is loaded thereon. The carriage 66 is slidably engaged with a guide shaft 67 and is partially connected (not shown) to a belt 69 which is driven by a motor 68. This permits the carriage 66 to move along the guide shaft 67 and move in the region of recording by the ink jet device 65 and the region adjacent thereto.
Reference numeral 51 denotes a sheet feeding part, and reference numeral 52 denotes a sheet feeding roller which is driven by a motor (not shown). This arrangement allows the recording paper to be fed to a position opposite to the orifice surface of the recording head and to be delivered to a take-off part having a take-off roller 53 during the progress of recording.
In the aforementioned arrangement, when the ink jet device 65 is returned to the home position at the end of recording, the cap 62 is retracted from the path of the movement of the ink jet device 65, while the blade 61 is projected in the path of the movement. As a result, the orifice surface of the ink jet device 65 is wiped by the blade 61. When the cap 62 contacts with the orifice surface of the recording head 65 so as to cap it, the cap 62 is moved so as to project in the path of the movement of the ink jet device 65.
When the ink jet device 65 is moved from the home position to the recording start position, the cap 62 and the blade 61 are at the same positions as the above-described positions in wiping. As a result, the orifice surface of the ink jet device 65 is wiped even during the movement of the ink jet device 65.
The recording head 65 is moved to the home position adjacent to the recording region not only at the end of recording and during the recovery of discharging (the operation of sucking an ink from an orifice in order to remover the normal discharge of an ink from an orifice), but also at predetermined intervals when it is moved in the recording region for the purpose of recording. This movement causes the above-described wiping.
FIG. 4 is a drawing which shows an example of an ink cartridge 45 for containing the ink to be supplied to the head through an ink supply tube. In the drawing, reference numeral 40 denotes an ink bag for containing the ink to be supplied which has a rubber stopper 42 at its one end. When a needle (not shown) is inserted into the stopper 42, the ink contained in the ink bag 40 can be supplied to the ink jet device 65. Reference numeral 44 denotes an ink absorber for absorbing waste ink. As the ink bag in the present invention, there may preferably be used ones of which the surface coming into contact with the ink is formed from polyolefins, in particular polyethylene.
The ink jet recording apparatus used in the present invention is not limited to an apparatus in which a device and an ink carriage are separately disposed, as described above. The ink jet device shown in FIG. 5 in which a device and an ink cartridge are integrated can be preferably used in the present invention.
In FIG. 5, reference numeral 70 denotes an ink jet device which contains an ink storing member impregnated with ink. The ink in the ink storing member is discharged as ink droplets from a head part 71 having a plurality of orifices. Further, as the ink storing member, there may be used an ink absorber or an ink bag. The head is the same as those referred to in FIGS. 1 and 2.
Reference numeral 72 denotes a communicating hole for allowing the inside of the device 70 to communicate with the atmosphere. As a material for the ink absorber in the present invention, there may be used polyurethanes.
The ink jet device 70 is used in place of the ink jet device 65 shown in FIG. 3 and is detachably provided on the carriage 66.
EXAMPLES
The present invention will be described below in detail by giving Examples and Comparative Examples. In the following, "%" is by weight unless particularly mentioned.
(1) Ink Preparation Examples:
Components as shown below were mixed, thoroughly stirred and dissolved, followed by pressure filtration using Fluoropore Filter (trademark); available from Sumitomo Electric Industries, Ltd.) with a pore size of 0.45 μm, to prepare inks of the present invention.
______________________________________Example 1Exemplary Dye No. 1 4%Thiodiglycol 5%N-methyl-2-pyrrolidone 10%Water 81%Example 2Exemplary Dye No. 3 2%Diethylene glycol 15%Water 83%Example 3Exemplary Dye No. 5 5%Diethylene glycol 15%Glycerol 2%Ethyl alcohol 4%Water 79%Example 4Exemplary Dye No. 6 3.5%1,3-Dimethyl-2-imidazolidinone 8%Ethylene glycol 12.5%Water 76%Example 5Exemplary Dye No. 10 4%Polyethylene glycol 15%(average molecular weight: 300)N-methyl-2-pyrrolidone 15%Water 76%Example 6Exemplary Dye No. 12 3%Glycerol 6%Diethylene glycol 14%Water 77%______________________________________
(2) Use Examples:
The inks of Examples 1 to 6 were each set on the ink-jet printer BJ-80A (manufactured by Canon Inc.; nozzle size: 50×40 μm; nozzle number: 24) that utilizes a heating element as an ink ejection energy source, and printing was carried out on the following recording medium A to C, under which evaluation was made on the clogging observed when the printing was stopped for a while and then again started, the performance of recovery from the clogging, observed when the printing was stopped for a long term and then again started, and the color change resistance.
Recording medium A; Ink-jet coated paper NM (trade name; available from Mitsubishi Paper Mills, Ltd.)
Recording medium B: Ink-jet coated paper, FC-3 (trade name; available from Jujo Paper Co., Ltd.
Recording medium C: Copy paper, Canon PAPER DRY (trade name; available from Canon Sales Inc.)
(3) Evaluation Method and Evaluation Results:
(i) Clogging observed when the printing was stopped for a while and then again started:
Judgement was made on whether defective prints such as blurs and defects of characters are seen or not, when the printing was stopped after alphanumeric characters were continuously printed on the recording medium C for 10 minutes using the printer filled with a given ink, and then the alphanumeric characters were again printed after the ink was left to stand for 10 minutes without capping on a nozzle or the like (which was left to stand at 20°±5° C. under 50±10% RH). As a result, no defective prints were seen.
(ii) Performance of recovery from clogging observed when the printing was stopped for a long term and then again started:
Judgement was made on how many times the operation for recovery had to be repeated to enable normal printing free from blurts or defects of characters, when the printing was stopped after alphanumeric characters were continuously printed on the recording medium C for 10 minutes using the printer filled with a given ink, and the operation for recovery of the clogging of nozzles were carried out after the ink was left to stand for 7 days without capping on a nozzle or the like (which was left to stand at 60° C. under 10±5% RH). As a result, normal printing became possible after the recovery operation was made once to five times.
(iii) Color change resistance:
Black solid patterns of 10 mm×30 mm were each printed on the recording mediums A, B and C. Thereafter, as a color change promotion means, the print was left to stand for 30 minutes in a light-intercepted chamber in which the density of ozone was always kept within the range of 0.1±0.05% by volume, and the color differences ΔR*ab after and before the test were measured (according to JIS Z8730). As a result, the ΔE*ab was found to be not more than 5 in all instances.
(4) Comparative Examples:
The above Examples were repeated to prepare 6 kinds of inks, except that the dyes used in the above Ink Preparation Examples 1 to 6 were replaced with C.I. Food Black 2, C.I. Direct Black 62, C.I. Direct Black 118, C.I. Acid Black 24, C.I. Acid Black 26, and C.I. Acid Black 60, respectively. Then the above Use Example was repeated using the recording apparatus to give black solid prints on the recording mediums A and B. Using the resulting prints as test pieces, similar tests were carried out using the above ozone test chamber. As a result, the ΔR*ab was found to be not less than 15 in all instances.
Further, with respect to each ink in Examples 1 to 6, the ink absorber of the ink-jet device as shown in FIG. 5 was impregnated with the ink. Then the ink jet apparatus as shown in FIG. 3 was allowed to carry the ink-jet device. By use of the ink jet apparatus, recording was performed. As a result, good recording which was excellent in a discharge property could be realized.
As described in the above, the present invention has made it possible to form an image not only having superior performances such as clogging resistance of inks, as generally required, but also having a superior color change resistance. | A recording process, ink-jet device, ink jet recording apparatus and ink cartridge employing an ink comprising a dye and a liquid medium, wherein said dye is a dye of Formula (I): ##STR1## wherein R 1 and R 2 represent independently an alkyl group, an alkoxy group or an acetylamino group; R 3 represents --SO 3 M or a hydrogen atom; R 4 represents a hydrogen atom, --SO 3 M or --NRR 5 , where R 5 represents a hydrogen atom, a phenyl group that may have a substituent, or a group of the formula ##STR2## where R 6 and R 7 represent independently a hydrogen atom or --C 2 H 4 OH; M represents an alkali metal; an ammonium group or an organic ammonium group; and l, m and n represent independently an integer of 0 or 1. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the field of optically controlled phased array antenna/radar systems. More particularly, the present invention relates to a system for creating continuous true time delays in a photonic beam array system, which is used to produce a microwave beam array with the same time delays to control/steer the propagation direction of the phased array antennas.
2. Description of the Related Art
Phased array antenna systems are well known in the art. A phased array may be used to point a fixed radiation pattern or to scan rapidly in azimuth or elevation.
Such systems can be used, for example, in a tracking system for tracking objects of interest such as aircraft or missiles, and in a high data rate wireless mobile communication system.
In order to steer a microwave beam from a phased array antenna, it is necessary to create a time delay t between the electromagnetic waves generated from each of the neighboring antenna elements in a particular direction.
Traditionally, the time delay in a phased array antenna system has been made by a microwave electronic delay device or an electronic phase shifter (which is not even a true time delay device). However, given the large number of antenna array elements needed, it is necessary to use a large number of delay devices and waveguides (cables), making the overall system very bulky and expensive. Moreover, such systems yield poor quality results.
In the last ten years or so, there have been extensive efforts to develop an optically controlled phased array antenna, in which time delays are generated in the optical domain and then are carried over to the microwave domain using optical fibers. However, most of such proposed schemes have failed because of significant technical difficulties or very expensive material and assembly costs due to their system complexity.
Thus, there exists a need in the art for a simplified and inexpensive system for generating a true time delay in a phased antenna array system.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a simplified and inexpensive true time delay device for optical control of a phased array antenna system.
To this end, according to the present invention, there is provided a true time delay system for optical control of a phased array antenna including a first time delay unit having a pair of parallel end walls having mirrored surfaces facing each other in a zigzag pattern, and an intermediate wall which is substantially parallel to the end walls and has mirrored surfaces on both sides which match the end walls. The intermediate wall also has matching openings in the mirrored surfaces to permit light to pass through the intermediate wall. A displacement unit displaces the intermediate wall relative to the end walls to change the distance that a series of input light beams travels, creating a true time delay in a first dimension. A second time delay unit receives the output of the first time delay unit, provides a time delay in a second dimension and outputs light beams having a time delay in both the first and second dimensions.
More particularly, the present invention is directed to a true time delay generator for optical control of a phased array antenna system having an array of antenna elements arrayed in a first dimension and a second dimension and having a number n of antenna elements in the first dimension and a number m of antenna elements in the second dimension, the generator comprising:
(a) first time delay means for providing a time delay for optical control of the phased array antenna system in the first dimension, the first time delay means for guiding a set of input light beams corresponding to the number n of antenna elements in the first dimension to provide an output comprising a first series of light beams, N in the total number, delayed relative to one another with an equal amount of time delay in the first dimension between each two consecutive light beams of the first series of light beams;
(b) splitter means for splitting each light beam of the first series of light beams to provide an output comprising N groups of M light beams;
(c) second time delay means for providing a time delay for optical control of the phased array antenna in a second dimension, the second time delay means for guiding the output of splitter means to provide an output comprising the N groups of M light beams in which the M light beams in each group are delayed relative to one another to have an equal amount of time delay between each two consecutive light beams in each group in the second dimension, the N groups of light beams constituting signals for optoelectric conversion for steering a propagation direction of the phased array antenna;
wherein the first time delay means comprises a delay generator unit and the second time delay means comprises N delay generator units, each of the delay generator units comprising:
(i) first and second end walls disposed substantially parallel to each other and forming a cavity therebetween, the first end wall having a first plurality of mirrors formed thereon and the second end wall having a second plurality of mirrors formed thereon to face the first plurality of mirrors;
(ii) an intermediate wall disposed between the first and second end walls and being substantially parallel thereto to form a first chamber and a second chamber in the cavity, the intermediate wall having a third and a fourth plurality of mirrors formed on opposite sides thereof to face respectively the first plurality of mirrors of the first end wall and the second plurality of mirrors of the second end wall, the intermediate wall having a series of apertures for passage of the input light beams from the first chamber to the second chamber; and
(iii) displacement means, for example, a motor, for displacing one of (1) the intermediate wall relative to the first and second end walls and (2) the first and second end walls relative to the intermediate wall, so that an area of the first and second chambers is variable for changing a time delay of the optical path of the input light beams in the cavity.
The set of input light beams are input into the first chamber of the first delay means so as to impinge on one of the third mirrors of the intermediate wall of the first delay means and then to reflect between the third mirrors and the first mirrors of the first delay means before passing through the apertures of the first delay means into the second chamber of the first delay means and then to reflect between the fourth mirrors and the second mirrors of the first delay means before passing out of the second chamber of the first time delay means and to the splitter means and then to the N delay generator units of the second time delay means as the N groups of M light beams, and each of the N groups of M light beams are input into the first chamber of a respective one of the N delay generator units so as to impinge on one of the third mirrors of the intermediate wall of the respective one of the N delay generator units and then to reflect between the third mirrors and the first mirrors of the respective one of the N delay generator units before passing through the apertures of the respective one of the N delay generator units into the second chamber of the respective one of the N delay generator units and then to reflect between the fourth mirrors and the second mirrors of the respective one of the N delay generator units before passing out of the second chamber of the respective one of the N delay generator units.
The N delay generator units of the second time delay means may be vertically stacked such that all N first and second end walls are attached together rigidly, and all N intermediate walls are attached together and movable together by the displacement means. The true time delay generator may further comprise amplification means for amplifying the output of the first time delay means. The light source for providing the input light beams may be a light source array positioned at an end of the intermediate wall of the first time delay means and may be a series of collimated lasers. The first, second, third and fourth plurality of mirrors may be curved concavely for retaining a collimation of the input light beams from the light source. A series of collimating lenses may be arranged in optical paths of at least one of the first and second time delay means. The displacement means may displace the intermediate wall relative to the first and second end walls for varying the size of the first and second chambers.
The plurality of mirrors of the intermediate wall and the end walls may be plated with a metal from the group consisting of Au, Ag, Al and Cr. The first and second plurality of mirrors may be arranged in a matching zigzag pattern at approximately ±45° angles to a normal axis of the first and second walls respectively and having grating surfaces thereon and the third and fourth plurality of mirrors may be arranged in a zigzag pattern at approximately ±45° angles to a normal axis of the intermediate wall and matching, respectively, the zigzag patterns of the first and second plurality of mirrors. The first and second walls may be connected by a pair of rods and the intermediate wall may be mounted to slide on the pair of rods.
According to another aspect of the present invention, there is provided a true time delay generator, comprising
(a) first and second end walls disposed substantially parallel to each other and forming a cavity therebetween, the first end wall having a first plurality of mirrors formed thereon and the second end wall having a second plurality of mirrors formed thereon to face the first plurality of mirrors;
(b) an intermediate wall disposed between the first and second end walls and being substantially parallel thereto to form a first chamber and a second chamber in the cavity, the intermediate wall having a third and a fourth plurality of mirrors formed on opposite sides thereof to face respectively the first plurality of mirrors of the first end wall and the second plurality of mirrors of the second end wall, the intermediate wall having a series of apertures for passage of the input light beams from the first chamber to the second chamber; and
(c) displacement means for displacing one of (1) the intermediate wall relative to the first and second end walls and (2) the first and second end walls relative to the intermediate wall, so that an area of the first and second chambers is variable for changing a time delay of the optical path of the input light beams in the cavity. Mirrors.
According to yet another aspect of the present invention, there is provided a method of true time delay for optical control of a phased array antenna system having an array of antenna elements arrayed in a first dimension and a second dimension and having a number n of antenna elements in the first dimension and a number m of antenna elements in the second dimension, comprising the steps of:
(a) inputting a set of input light beams, corresponding to the number n of antenna elements in the first dimension, into a first chamber of a first delay unit so as to impinge on one of a plurality of third mirrors of an intermediate wall of the first delay unit;
(b) reflecting the set of input light beams between the third mirrors and a plurality of first mirrors of the first delay unit;
(c) passing the input light beams through a plurality of apertures formed in the first delay unit into a second chamber of the first delay unit;
(d) reflecting the input light beams within the second chamber between fourth mirrors formed on the intermediate wall and second mirrors formed on the second wall of the first delay unit;
(e) passing the input light beams out of the second chamber of the first time delay unit to provide an output comprising a first series of light beams, N in number, delayed relative to one another with an equal amount of time delay in the first dimension between each two consecutive light beams of the first series of light beams;
(f) splitting each light beam of the first series of light beams to provide an output comprising N groups of M light beams;
(g) providing the N groups of M light beams to respectively a first chamber of N delay generator units of a second time delay means so as to impinge on one of a plurality of third mirrors formed on an intermediate wall of the respective ones of the N delay generator units;
(h) reflecting the N groups of M light beams between the third mirrors and first mirrors formed on a first wall of the respective ones of the N delay generator units;
(i) passing the N groups of M light beams through the apertures of the respective ones of the N delay generator units into a second chamber of the respective ones of the N delay generator units;
(j) reflect the N groups of M light beams between fourth mirrors formed on a second wall of the respective ones of the N delay generator units and the second mirrors of the respective ones of the N delay generator units; and
(k) passing the N groups of M light beams out of the second chamber of the respective ones of the N delay generator units.
The method may comprise displacing one of (i) the first and second walls relative to the intermediate wall and (ii) the intermediate wall relative to the first and second end walls, to change a time delay of an optical path of light beams in the first and second chambers. The method may further comprise amplifying the output of the first time delay unit; and splitting the output amplified in step (v) for input to the plurality of N generator units of the second time delay unit. The method may further comprise collimating the series of input beams provided to the first delay unit.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 ( a ) illustrates a two-dimensional phased array antenna panel.
FIG. 1 ( b ) depicts the x-component of the beam generated by the panel shown in FIG. 1 ( a ).
FIG. 1 ( c ) depicts the y-component of the beam generated by the panel shown in FIG. 1 ( a ).
FIG. 2 is a block diagram of a true time delay generator of the present invention.
FIG. 3 shows details of the true time delay generator shown in FIG. 2 .
FIG. 4 is a face view of the intermediate wall of one of the TTD units in FIG. 3 .
FIG. 5 is a flowchart illustrating a two-dimensional true time delay of the present invention.
FIG. 6 shows details of sub-steps which correspond to step 510 in FIG. 5 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following embodiments of the present invention are provided for illustrative purposes only.
FIG. 1 ( a ) shows a phased antenna array panel 1 which is optically controlled in accordance with the present invention. Antenna array panel 1 comprises an array of antenna elements 2 arranged in a series of rows and columns. Panel 1 emits a beam 3 which forms an angle with the z-axis normal to the surface of the antenna array panel 1 .
FIG. 1 ( b ) shows the x-component of beam 3 , while FIG. 1 ( c ) shows the y-component of beam 3 . Between each two neighboring antenna elements in the x array, there is a time delay t x for the waves emitted/received by the elements, which causes a different traveling distance c t x (where c is the speed of light) for neighboring antenna elements 2 . Therefore, for the nth antenna element in the x-direction, there is n t x time delay relative to the first antenna element 2 in the row. Similarly, for the y-direction, there is m t x time delay between the first and the mth antenna element.
FIG. 2 is a block diagram of the true time delay generator of the present invention, which may produce up to N delay lines. This generator achieves two-dimensional steering by employing first and second units 4 and 5 for the optical control of the phased array antenna panel shown in FIG. 1 ( a ). First unit 4 is for steering in the x-direction, and second unit 5 is for steering in the y-direction. Second unit 5 includes N vertically stacked sub-units 5 a as shown. First and second units 4 and 5 operate on the same principle, except for the size and the number of total reflection mirror pairs M (discussed below), which matches the number of antenna elements m in the y-direction.
In FIG. 2, a plurality of input light beams 6 , from 1 to N, are input to the first unit 4 and then output with a same amount of time delay between each two adjacent beams in the first dimension (x-direction). The N output beams will have respective time delays of 1 t x , 2 t x , 3 t x , . . . N t x , where t x can be continuously varied from—t max to t max , and t max is the time delay corresponding to the maximum angle of the beam steering in one direction.
The N output beams 7 from first TTD unit 4 (which may be amplified by amplifiers 8 ) are then input respectively to the sub-units 5 a of second TTD unit 5 via M splitting units 10 associated with the M sub-units 5 a respectively. The N beams 7 then undergo a time delay in the second dimension (y direction) to produce output light beams 11 from the second TTD unit 5 , which have time delays N×M in the first and second dimensions (i.e. x and y directions) for optical control of the antenna array panel 1 .
It will be understood by those of ordinary skill in the art that when the phased antenna array panel 1 is in transmission mode, the output beams 11 from the second TTD unit 5 may be read, for example, by photosensors (not shown) for conversion to electrical signals to control the antenna array panel 1 during the transmission.
It will be further understood by those of ordinary skill in the art that when the phased antenna array panel 1 is in reception mode, a series of laser diodes (not shown) can provide the optical conversion of the signals received by the antenna panel 1 for input to the TTD units 4 , 5 .
FIG. 3 shows details of an embodiment of the first TTD unit 4 of the present invention. It should be noted that, although details of the first TTD unit 4 are described below, the second TTD unit 6 has a similar construction to the first TTD unit.
TTD unit 4 has a first end wall 12 and a second end wall 13 , which are substantially parallel to each other and connected by rods 14 so as to form a cavity 15 having a length 2 L and a width W.
First end wall 12 has formed thereon, on an inward facing side thereof, a first plurality of mirrors 12 a . The first plurality mirrors 12 a are arranged in a zigzag pattern at approximately ±45° angles from the normal direction of end wall 12 .
Second end wall 13 also has formed thereon, on an inward facing side, a second plurality of mirrors 13 a . The second plurality of mirrors 13 a are arranged in a zigzag pattern, which matches the zigzag pattern 12 a of the first end wall 12 , at approximately ±45° angles from the normal direction of end wall 13 .
First TTD unit 4 has an intermediate wall 16 which is disposed between and substantially parallel to the first and second end walls 12 , 13 so as to form a first chamber 17 and a second chamber 18 in cavity 15 .
The intermediate wall 16 has two sides, respectively having formed thereon a third plurality of mirrors 16 a and a fourth plurality of mirrors 16 b . The third and fourth plurality of mirrors 16 a , 16 b are arranged in zigzag patterns at approximately ±45° angles from the normal direction of wall 16 . The zigzag patterns of mirrors 16 a , 16 b on each side of intermediate wall 16 matches the pattern of the mirrors of the respective end wall 12 or 13 , which they face.
Intermediate wall 16 is slidably attached to connecting rods 14 to permit motion of intermediate wall 16 relative to end walls 12 and 13 . Alternatively, the end walls could be mounted to slide relative to the intermediate wall.
A diagonal series of apertures 19 (shown in FIG. 4) extends through intermediate wall 16 to permit passage of light beams from the first chamber 17 to the second chamber 18 .
Light source array 20 , which may comprise a series of collimated lasers or light sources, is arranged at an end of the intermediate wall 16 and provides collimated input beams to the TTD unit 4 .
In order to retain the collimation of (or to collimate) the output of light source array 20 , all of the mirrors of the end walls and intermediate wall may be curved concavely. Alternately (or additionally), a series of collimating lenses, such as 29 , may be provided in the optical path to obtain collimation of the light beams. It should be noted that the collimating lenses may be positioned at any advantageous position to achieve the desired collimating effect.
A displacement unit 21 , typically a motor, displaces the intermediate wall 16 relative to the end walls 12 and 13 so as to vary the area of the second and first chambers 17 and 18 .
When the intermediate wall 16 is arranged at the intermediate (or center) position, the true time delay unit 4 does not provide a time delay, because the first and second chambers 17 and 18 have an equal size and all of the light beams travel the same distance through the true time delay unit. Thus, the microwave beam front will propagate in the normal direction relative to antenna panel 1 .
However, as shown in FIG. 3, when the intermediate wall 16 is displaced by l from the intermediate position, the Kth laser beam 22 (4 th beam in the figure) makes K total reflections (in this case 4 round trips) in the first chamber 17 , passes through an opening 19 (see FIG. 4) in the intermediate wall 16 and makes N−K total reflections (in this case 6 round trips) in the second chamber 18 .
At the output of first TTD unit 4 , the Kth beam travels a path of X k =2K(L+l)+2(N−k+1)(L−l)+W (where W is the width of the TTD unit 4 shown in FIG. 3 ). Therefore, the difference in the path length between two consecutive light beams (k and k+1) is 2 l. The first TTD unit 4 will generate an array of N light beams having 1(2 l), 2(2 l), 3((2 l), 4(2 l), . . . k(2 l) . . . N(2 l) in path difference, respectively. of course, if l is zero, the path differences will be zero.
When t x =c2 l, where c is the speed of light, the TTD unit 4 then generates an array of light beams having a true time delay of 1 t x ,2 t x ,3 t x , . . . N t x , respectively, which corresponds to a steering of the microwave beam front to one direction from the phased array antenna panel 1 .
When the intermediate wall 16 is moved to the first side position (−l), “negative” time delays correspond to a steering of the microwave in an opposite direction.
Mirrors 12 a , 13 a , 16 a and 16 b may be formed by plating with a metal such as Au, Ag, Al or Cr.
In addition, the gratings of the intermediate wall 16 and the end walls 12 and 13 should be larger than the light beam size and wavelength.
Finally, the height of the mirrors 12 a , 13 a , 16 a and 16 b should be sufficient to receive plural light beams at the same time.
FIGS. 5 and 6 are flow charts illustrating the true time delay method of optical control of a phased array antenna according to the present invention.
At step 500 , a series of light beams are provided to a first true time delay unit 4 , for example, by a light source array 20 provided at an end of a intermediate wall 16 of the first TTD unit 4 .
At step 510 , the first TTD unit 4 performs a time delay which is equal for each two consecutive input beams for optical control of the phased array antenna elements 2 in a first dimension.
At step 520 , the N beams output from the first TTD unit are split into N sets of M beams and are provided to the second TTD unit 5 .
At step 530 , a second TTD unit 5 receives the output of the first TTD unit 4 and performs a time delay for optical control of the phased array antenna elements 2 in a second dimension.
At step 540 , the output of the second TTD unit 5 , which has a time delay in the first and second dimensions, is output to the phased antenna array panel 1 for steering the propagation direction of a beam 3 emitted by the phased array antenna panel 1 .
FIG. 6 is a flowchart which shows details of step 510 of FIG. 5 .
Step 511 involves displacing either first and second end walls 12 and 13 relative to the intermediate wall 16 or the intermediate wall 16 relative to the first and second end walls 12 and 13 , to change a time delay of an optical path of light beams in the first and second chambers 17 and 18 .
Step 512 involves amplifying the output of the first time delay unit.
Step 513 involves splitting the output amplified in step 512 for input to a plurality of sub-units 5 a of the second time delay unit 5 .
Step 514 involves displacing either the first and second end walls 12 and 13 relative to the intermediate walls 16 or the intermediate walls 16 relative to the first and second end walls 12 and 13 of the subunits of the second TTD unit 5 , to change a time delay of the optical paths of light beams in the first and second chambers 17 and 18 of the second unit 5 .
It is noted that sub-steps 512 and 513 are optional, because the amplification (or the splitting) may not be necessary depending upon the number of sub-units 5 a used in the second TTD unit 5 .
The sub-steps of performing a time delay in the second TTD unit 5 is similar to those illustrated in FIG. 5 and 6, except that the input light beams are provided by the output of the first TTD unit 4 after passing through the beam splitters 10 , and the output of the second TTD unit 5 is provided to the phased antenna array elements 2 via a photodetector array or similar devices (not shown) as microwave generators.
It is within the scope of the method of the present invention to collimate the series of input light beams which are provided to the first delay unit 4 by providing, for example, collimating lenses, such as element 29 , in the optical path of each light beam, and/or providing each of the respective plurality of mirrors 12 a , 13 a , 16 a and 16 b with a concavely curved surface.
Further, in the above method, a distance between the gratings of the mirrors 12 a , 13 a , 16 a and 16 b should be larger than a size and wavelength of the input light beams, and the height of the mirrors 12 a , 13 a , 16 a and 16 b should be high enough to receive plural light beams at the same time.
Although the present invention has been fully disclosed by way of examples with reference to the accompanying drawings, it should be understood that numerous variations, modifications and substitutions will be apparent to those skilled in the art without departing from the novel spirit and scope of this invention.
For example, the first and second walls may be supported independently and need not be connected by connecting rods; for example, tracks may be used to guide/retain the walls during displacement, and the displacement device could be any structure for moving the walls and need not be a motor. Also, any desired number of light beams may be employed. Moreover, in some applications, the time delay for each two consecutive beams need not be equal; any desired arrangement to achieve various true time delays of different antenna elements relative to the first antenna element in the row or column may be designed. It will be further apparent that various shapes of the mirrors of the end walls and the intermediate wall may be utilized. In addition, the series of apertures in the intermediate wall can be in an arrangement other than diagonal to achieve a desired set of true time delays. Another example, instead having N vertically stacked TTD generator units for the second dimension time delay, a large single TTD generator unit can be used by having the N groups of M light beams sharing different part of the Moreover, optical path switching devices other than mirrors may be employed to switch the light beams along different length optical paths prior to exiting the TTD device. Another example, instead having N vertically stacked TTD generator units for the second dimension time delay, a large single TTD generator unit can be used by having the N groups of M light beams sharing different part of the mirrors. | A true time delay system for optical control of a phased array antenna includes a first time delay unit having a pair of parallel end walls having mirrored surfaces facing each other in a zigzag pattern, and an intermediate wall which is substantially parallel to the end walls and has mirrored surfaces on both sides which match the end walls. The intermediate wall also has matching openings in the mirrored surfaces to permit light to pass through the intermediate wall. A displacement unit displaces the intermediate wall relative to the end walls to change the distance that a series of input light beams travels, creating a true time delay between each two consecutive light beams in a first dimension. A second time delay unit receives the output of the first time delay unit, provides a time delay between each two consecutive light beams in a second dimension and outputs light beams having a sequence of time delay in both the first and second dimensions. | 7 |
FIELD AND BACKGROUND OF THE INVENTION
[0001] This invention relates generally to bulk milk tanks used in dairies, and more particularly to a bulk milk tank with an attached ladder that provides access to a raised platform for monitoring a milk gauge and obtaining milk samples. At least a portion of the ladder can be moved away from a tank outlet valve to provide easier access to the outlet valve.
[0002] In dairies, milk is collected from a number of cows through a milking system and directed to a bulk milk tank for storage until the milk is transported off site. Bulk milk tanks are typically quite large cylindrical shapes with a longitudinal axis that is oriented horizontally. The ends of the tank are capped with convex ends to provide maximum storage capacity.
[0003] Space being at a premium in many dairies, the tanks are designed to have all of their necessary functional elements accessible at one end of the tank. These elements include: an external milk gauge rod for determining the quantity of milk in the tank; an outlet valve for connecting to wash pumps, off-load pumps, or milk inlet lines; an access hatch on the top or end of the tank for obtaining milk samples; an elevated platform for operators to stand on while reading the milk gauge and taking milk samples; and a ladder for the operator to reach the platform.
[0004] For safety reasons, the ladder is mounted on the tank to avoid the dangers associated with using a separate, and possibly unstable, ladder resting on the floor. Attached ladders provide operators with secure movement to and from the elevated platform.
[0005] Unfortunately, ladders fixed to the end of a bulk milk tank consume a lot of space. Access to other elements, such as the outlet valve, can be inhibited by the ladder. Thus, what is needed is a bulk milk tank with a securely attached ladder that provides access to the elevated platform and ample clearance to use the outlet valve.
SUMMARY OF THE INVENTION
[0006] The present invention is directed to a bulk milk tank having an attached ladder that moves between a lowered position to provide access to an elevated platform and a raised position to provide clearance for an outlet valve mounted near the tank bottom. This ladder provides benefits that are not known in any prior milk tank ladder.
[0007] In its lowered position, the ladder provides access to the upper platform of the bulk milk tank. From the platform, milk samples and quantity readings can take place. After sampling, a portion of the ladder can be moved to a raised position to provide clearance and easy access to the milk outlet valve, which would otherwise be at least partially blocked by the ladder.
[0008] Preferably, the ladder includes a lower section that slides relative to the upper section and is locked in the raised position by a pivoting latch.
[0009] Risers to act as handrails can also be included, particularly near the top so that the user can move easily from the ladder to the tank platform and back again.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] [0010]FIG. 1 is a perspective view of a bulk milk tank with a ladder in a lowered or climbing position in accordance with the present invention.
[0011] [0011]FIG. 2 is a perspective view of the bulk milk tank of FIG. 1 with the ladder in a raised position.
[0012] [0012]FIG. 3 is a front view of an upper section of a milk tank ladder in accordance with the present invention.
[0013] [0013]FIG. 4 is a side view of the ladder upper section of FIG. 3.
[0014] [0014]FIG. 5 is a front view of a ladder lower section in accordance with the present invention.
[0015] [0015]FIG. 6 is a side elevation view of a lock to releasably maintain a lower ladder section in a raised position, in accordance with the present invention.
[0016] [0016]FIG. 7 is a front elevation view of a pivoting lock latch used in the lock of FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] Illustrated in FIG. 1 is a bulk milk tank and ladder system 20 in accordance with the present invention. The bulk milk tank and ladder system 20 includes a milk storage tank 22 , a series of supporting legs 24 , a ladder 26 , an outlet valve 28 , a milk gauge 30 , and a platform 32 .
[0018] The milk tank 22 is preferably made of stainless steel and can hold from 600 gallons to 8000 gallons of milk from dairy animals being milked in a dairy. The tank 22 is generally cylindrical and has a substantially horizontal longitudinal axis extending from front 36 to back 38 of the tank 22 . The tank 22 is supported above a floor by legs 24 .
[0019] The front 36 of the tank 22 is preferably substantially round in cross-section and is convex to increase tank storage capacity. The surface of the tank 22 is smooth and has no integral means for ascending to the access hatch 33 . Instead, a ladder 26 is joined to the front of the tank 22 by any suitable means including welds, bolts, or other type of fastener.
[0020] The ladder 26 includes an upper section 40 and a lower section 42 . As seen in FIGS. 3 and 4, the upper ladder section 40 includes a pair of posts 46 that are oriented generally vertically and spaced apart from the upper portion of the tank front 36 to provide an easy handhold and clearance for the operator's feet while climbing. Joined to the bottom of the posts 46 are horizontal struts 48 that join the tank 22 to the posts 46 to maintain spacing.
[0021] At the top of the posts 46 are risers 50 that spread outwardly from the posts 46 to provide handrails and ample working space for taking samples through the access hatch 33 . The risers 50 are joined to the topside 52 of the tank 22 . A ladder rung 54 spans the space between the posts 46 . The number of ladder rungs is not critical so long as all applicable safety codes and regulations are met. Preferably, the ladder rungs 54 are an inverted U-shape and have perforations for traction. (See: FIG. 6.)
[0022] Also joined to the posts 46 , is a platform 32 on which an operator can stand while taking measurements from the milk gauge 30 or taking samples through the access hatch 33 . The platform 56 is joined to or is part of the ladder 26 in preferred embodiments, but a separate platform could be attached to the tank 22 . The platform 32 is preferable to a ladder rung because there is more space to support the operator and less chance for foot fatigue or slipping.
[0023] The posts 46 also include four brackets 58 that serve to joint the upper ladder section 40 to the lower ladder section 42 . The brackets 58 are generally c-shaped and open inward toward the center of the ladder 26 . Inside of the c-shaped brackets are bushings 60 (See: FIG. 2), preferably plastic, that provide a close and low friction fit with the lower ladder section 42 .
[0024] All of the components described above as being part of the upper ladder section 40 can be welded together to form a single weldment that itself is welded to the tank 22 . Otherwise, these same components can be joined to one another and the tank 22 in any suitable fashion.
[0025] The lower ladder section 42 (FIG. 5) includes a pair of substantially vertical posts 66 that are sized to mate with the bushings 60 in the brackets 58 of the upper ladder section 40 . Spanning the distance between the posts 66 are rungs 68 , preferably six (6) in number and welded to the posts 66 . More or fewer rungs 68 can be used to compliment the size of the milk tank 22 on which the ladder 26 is mounted. On top of the posts 66 are caps 69 that are oversized relative to the cross-sectional area of the posts 66 so that they act as stops to prevent the lower ladder section 42 from sliding out of the brackets 58 of the upper ladder section 40 .
[0026] With this construction, the ladder 26 can be used in a climbing position (FIG. 1) to access the platform 32 or in the raised position (FIG. 2) to have clearance for the outlet valve 28 by sliding the lower ladder section 42 relative to the upper ladder section 40 .
[0027] A lock 70 is used to secure the lower ladder section 42 in its raised position (FIG. 2) while the outlet valve 28 is being accessed by an operator.
[0028] A lock 70 for use with the present invention is illustrated in FIGS. 6 and 7. The lock 70 includes a pin 72 joined to or molded integrally with the lower ladder section 42 , and preferably to a rung 68 of the lower ladder section 42 via a bolt 73 . The lock 70 also includes a pivoting latch 74 that is joined to the upper ladder section 40 via a bolt 75 . The latch 74 engages the pin 72 to maintain the lower ladder section 42 safely and conveniently clear of the outlet valve 28 in the raised position.
[0029] The pivoting latch 74 includes an upper handle portion 76 that can be manipulated from outside of the ladder post 46 to avoid a pinch point. On the opposite end is a hook 80 that is sized and shaped to mate with the pin 72 .
[0030] On the underside of the hook 80 is a cam surface 82 that is engaged by the pin 72 when the lower ladder section 42 is being raised. The engagement of the pin 72 and the cam surface 82 pivots the latch 74 (counter-clockwise as viewed) enough to allow the pin 72 to be raised above the latch 74 . Either gravity, a spring, or manipulation by the user pivots the latch 74 (clockwise as viewed) to position the hook 80 under the pin 72 , so that slight downward movement of the lower ladder section 42 engages the pin 72 and the hook 80 to secure the lower ladder section 42 in a raised position.
[0031] In a preferred embodiment, a tab 88 is formed on the hook 80 to add mass to the latch 74 . With the added mass, gravitational force is enough to rotate the latch 74 in a clockwise direction to a position that will support the pin 72 . In addition, a spring could be used to assist in the rotation of the latch 74 , but one is not necessary in the illustrated, preferred embodiment.
[0032] A stud 86 engages the pin 72 in the event an operator raises the lower ladder section 42 too far. The stud 86 thereby limits how far the lower ladder section 42 can be raised.
[0033] To lower the lower ladder section 42 to the climbing position, the operator slightly raises the lower ladder section 42 to clear the hook 80 . The operator then uses the upper handle portion 76 of the latch 74 to pivot the latch 74 counter-clockwise while simultaneously lowering the lower ladder section 42 toward the climbing position. Once the pin 72 is below the latch 74 , the latch 74 can be released.
[0034] The lock 70 is illustrated as a latch and pin combination, but any type of mechanism that maintains the lower ladder section 42 in the raised position can be used.
[0035] Aside from the plastic bushings 60 , all of the ladder elements are preferably made of stainless steel.
[0036] The illustrated embodiment has a lower ladder section 42 that slides relative to the upper ladder section 40 , but it is possible to join the sections with hinges to pivot the lower section upward to provide access to the outlet valve. In all of these embodiments, the ladder has essentially two positions. First a climbing position to provide climbing access to the elevated platform. Second, a raised position where a section of the ladder is moved away from the outlet valve to permit necessary operations to take place on the valve. Nonetheless, the sliding embodiments require no clearance for the lower section to swing through, so the sliding version is more space economical.
[0037] The foregoing detailed description is provided for clearness of understanding only and no unnecessary limitations therefrom should be read into the following claims. | A bulk milk tank having a ladder that provides access to a raised platform in a lowered position and moves to a raised position to provide ample operating room around the tank outlet valve. | 8 |
BACKGROUND OF THE INVENTION
Cross Reference to a Related Application
This patent application is a continuation-in-part of a previously filed and copending application by the same inventors, entitled "Shroud for an Engine Cooling Fan"; filed Aug. 12, 1998 assigned Ser. No. 09/132,884.
FIELD OF THE INVENTION
This invention generally relates to cooling of an internal combustion engine of a vehicle and more particularly to a new and improved fan shroud for an engine adapted to overlie a generally rectangular shaped radiator and featuring internal vanes arranged in strategic corner areas in the shroud that direct peripheral air passing through the corners of the radiator directly to the fan blades so that the blades are preloaded so as to enhance fan efficiency in pumping air through the radiator therefore improving the overall heat exchange for the engine.
SUMMARY OF THE INVENTION
Vehicles typically include an internal combustion engine, a radiator for cooling the engine, and an engine driven fan for causing air to flow through the radiator. Under idle and lower speed operation, the ability of the radiator to cool the engine is determined, in part, by the capacity of the cooling fan in producing an air flow through the radiator, often referred to as the fan efficiency or capacity. Accordingly, vehicle manufacturers are always looking for simple and inexpensive ways in which to increase engine cooling fan efficiency.
Most engine cooling fans are encircled by a shroud member which are designed to enhance the efficiency of the cooling fan as well as to prevent the insertion of foreign objects, such as debris, or tools, into the blades of a moving fan. Accordingly, it would be desirable to maximize the efficiency of the shroud by providing vanes which define air channels that increase air flow through the radiator and to the engine cooling fan. The subject invention provides a fan shroud intended for use with an engine driven fan which has blades that rotate in a predetermined direction. The fan shroud includes a generally flat deflecting portion having a surface spaced from and overlying the generally rectangular configured radiator. The deflecting portion is integrally connected to a tubular collar or ejector portion defining an aperture sized and positioned to receive the fan. Also, a reinforced edge is disposed along the outer perimeter of the deflecting portion. A plurality of vanes, each having a generally semi-circular shape, extend between the reinforced edge and the aperture of the collar portion. These vanes direct streams of air from the radiator, particularly corner portions thereof, to the fan receiving aperture portion and in a direction opposite to the predetermined rotation of the fan blades. In the preferred embodiment of the present invention, the vanes are arranged in substantial parallelism to form rows therebetween from the reinforced edge and the collar's aperture so as to define separate air channels between adjacent vanes.
The present invention overcomes several shortcomings of prior art engine fan shrouds. Foremost, the present invention increases both engine cooling performance and air conditioning performance. Further, the subject shroud is strong, durable, and easily serviced.
Prior to the present invention, various fan shroud arrangements have been provided for automobile engine cooling fans. U.S. Pat. No. 5,224,447 dated issued Jul. 6, 1993 for "An Air Guide For A Fan Impeller Of An Internal Combustion Engine" discloses a cowl ring disposed around an engine cooling fan having a plurality of outflow openings and associated external air guide vanes for improving the radial outflow of the fan to reduce pressure losses in the outflow in a radial direction. U.S. Pat. No. 5,410,992 issued May 2, 1995 for "Cooling System For Automotive Engine" discloses a variable geometry fan duct having a fixed barrel segment for an axial flow cooling fan and a movable barrel segment rotatably mounted on the fixed segment movable to a position in which the fan blades are completely encircled to provide the variable geometry. U.S. Pat. No. 4,329,946 issued May 18, 1982 for "Shroud Arrangement For Engine Cooling Fan" discloses fixed and rotatable shrouds for an associated engine cooling fan to improve the efficiency of the fan.
While the prior art disclosures provide different shroud structures for engine cooling fans to improve fan performance, they do not meet higher standards for improved air intake into the fan and particularly an improvement in air flow associated with the corner areas of the fan shroud and the associated rectangular radiator. Nor do they actively direct air to the pumping surfaces of the engine cooling fan blades for increasing fan pumping efficiency. More particularly the prior art does not disclose or suggest the strategic arrangement of vanes located internally of the fan shroud and particularly in the corner areas thereof for controlling and directing the air flowing through the corner regions of the radiator and creating a swirling air flow pattern directed to pass air toward the pumping surfaces of the fan blades so that the blades are preloaded and therefore more efficient to pump larger quantities of air in a more effective operational mode of air flowing through the radiator. Thus, the present invention increases the cooling performance of the radiator type cooling system for an internal combustion engine and even increases the air conditioning performance of an associated air conditioning condenser by increasing air flow therethrough at all engine and vehicle speeds. With this invention fan noises are decreased and the shroud is structurally stronger while accessibility and serviceability of the fan is maintained.
In a preferred embodiment of this invention, a multi-bladed axial or mixed flow fan is encircled by a collar or curved ejector portion of a fan shroud which extends rearwardly from an open box section or flow diverting portion thereof. The flow diverting portion is supported in overlying relationship to a generally rectangular radiator. Air flows through the radiator when the fan is operational, particularly when the engine is idling or under lower speeds of the vehicle. Under these conditions, an improvement in heat exchange of the radiator cooling system is very desirable. In regions radially outward of the generally circular fan, streams of peripheral air are feed to the fan, i.e., air outward of the fan's diameter passes through the comers of the radiator and radially inward to the fan. In the subject arrangement, the peripheral air flow is channeled by a plurality of curved vanes formed in the flow diverting portion of the shroud and directed inwardly in a swirling pattern in a rotational direction counter to the fan's normal rotational direction. The inwardly swirling flow of this air desirably preloads the fan blades by impinging on the working side of the fan blades so that the fan's air pumping and heat exchange efficiencies are improved. Moreover, the internal vanes provide improved structural strength to the shroud. The subject vane arrangement further reduces noise levels originating from fan operation and improves the efficiency of the air conditioning system particularly where the air conditioning condenser is located adjacent to the radiator and the shrouded fan pulls greater quantities of outside air over the total surface of the condenser.
Another feature and object of this invention is to provide a new and improved fan shroud, adapted to accommodate a rotatable multi-bladed engine cooling fan, having internal vanes in strategic areas such as the corners of the shroud that direct inwardly swirling streams of air into the rotating fan and in a rotational direction counter to the direction of fan rotation to preload the pumping surfaces of the fan blades to improve fan output and operating efficiency.
These and other features of the invention will become more apparent from the following detailed description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a vehicle with portions of its front end broken away, such as the radiator, to expose an engine fan and a fan shroud in accordance with the present invention; and
FIG. 2 is a pictorial view of an engine driven cooling fan, and associated fan shroud, a conventionally rectangularly shaped radiator for circulating engine coolant therethrough, and a vehicle air conditioning condenser; and
FIG. 3 is a elevational view partially in section of an engine fan, an associated fan shroud, a radiator, and also showing a portion of the vehicle engine which rotates the fan; and
FIG. 4 is a sectional view taken generally along section line 4 - 4 of FIG. 3; and
FIG. 5 is an enlarged view similar to FIG. 3 of a portion of the fan, the shroud, and the radiator; and
FIG. 6 is a diagram illustrating an operational improvement of the subject fan shroud.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now in greater detail to the drawing, FIG. 1 shows a perspective view of a vehicle 10 with portions of a front end of the vehicle 10 broken away to expose an engine fan shroud 12 in accordance with the present invention. The shroud 12 is designed to shield an engine driven fan 14 commonly referred to as an engine cooling fan. The engine cooling fan 14 includes blades 16 which rotate in a predetermined direction. As illustrated in FIG. 1, the blades 16 of the engine cooling fan 14 rotate in counter-clockwise rotation, generally indicated by the dashed arrow. Rotation of the fan 14 draws air through an engine radiator which has been removed in FIG. 1 to better illustrate the shroud 12 and fan 14. The radiator is shown in latter views to be described hereinafter.
FIGS. 2 and 3 show fan shroud 12 as including integral attachment tabs 13 for receiving threaded fasteners 15 (see FIG. 5) which operatively secure the shroud to bracket structure 17 associated with an engine coolant circulating radiator 18. Radiator 18 has a conventional rectangular configuration through which air flows as indicated by arrowed lines A in FIG. 2. Alternatively, the bracket structure or other shroud support could be attached to some other structure in the engine compartment 20 of the associated vehicle. The fan shroud 12 is molded or otherwise formed from an engineering plastics or other suitable material. Preferably, the fan shroud 12 has a box-like main body portion 24 best seen in FIG. 2. The main body portion 24 has an opened front face which is bordered by and defined by a generally rectilinear wall portion 26. The shroud is supported via wall portion 26 as it includes the tab portions 13 previously discussed. The shroud 12 also includes a generally cylindrically configured collar portion 28 which extends axially from an interior surface of a back wall 30 of the main body portion 24. Collar portion 28 is adapted to encircle the fan 14 and its blades 16. This relationship with the fan serves to allow the collar portion to act as an air ejector or enabler for air flow from the interior of the main body portion 24 and thus from the radiator 18.
FIGS. 2 and 4 best show the interior regions of the body portion 24 of the fan shroud 12. Shroud 12 includes the wall portions 30 which extend radially inward from the outer wall portion or frame 26 to the collar or ejector portion 28. Specifically, the wall portions 30 extend from corner portions of the rectangularly configured main body portion 24 to the central collar 28. The wall portions 30 connect with the collar at an inner or leading edge portion 34 which forms a transition between the interior of the main body portion and the collar portion. The wall portions 30 supports a plurality of curved air directing vanes 36 which extend away from the interior surface. In a preferred embodiment, the vanes are integrally formed with the main body portion 24 but the vanes could be otherwise secured to the shroud.
The vanes 36 are located radially outward and generally upstream of collar portion 28 and spaced from one another to form air flow passages or channels 38 therebetween. Since the vanes are substantially located at the corners of the main body portion 24 of the shroud and radiator 18, these passages 38 permit air exiting peripheral or outer corner portions of the radiator to pass away from the radiator's downstream discharge surface and then flow radially inward as best illustrated in FIG. 5 by the arrowed line 40. As seen in FIG. 4, the vanes 36 also cooperatively impart an inwardly directed and rotational swirling pattern or stream of air labeled as path P. The rotation of the swirling air along paths P is counter to the fan's direction of rotation which is labeled R in FIG. 4. The path P is operated upon by the blades 16 of the fan 14 as air enters and passes through the fan shroud's ejector portion 28.
As best seen in FIG. 3, the fan assembly 14 includes a central hub portion 42 which is operatively attached to an internal combustion engine 44 rearwardly of the radiator 18. A conventional fan assembly 14 usually includes a viscous fluid clutch arrangement 46 which has an input portion attached to the engine shaft and driven by a "V" belt and pulley drive system 48. The viscous clutch unit 46 has a downstream or output side with a mounting shoulder 50 on which the fan's hub 42 is secured by fasteners 52. The fan assembly 14 has a plurality of radially extending blades 16 that are arcuately spaced from one another and extend radially outwardly from the central hub portion 42. The fan blades 16 are preferably identical and each section of the blades has a cord length defining the angle of attack with respect to the straight or head on flow of air which has directly passed through the radiator and into the plane of fan rotation. This air flow also engages the swirling flow of air from the vanes 36 and taking air paths P.
As previously explained, the vanes 36 are separated from one another to form air flow channels or passages 38. The vanes 36 are angled or turned in a desired direction to direct streams of air flow into contact with the fan blading 16. More particularly and as illustrated in FIG. 4, the flow of air from vanes 36 is turned in a direction P against the counter-clockwise rotation R of fan assembly 14. This flow of air against the fan blades 16 advantageously preloads the downstream or suction side of the fan blades so that fan operation is made more effective in pumping air. With the improved pumping action, the fan effectively improves the flow of air through the radiator therefore improving heat transfer efficiency of the engine cooling system.
In addition to an increase of the flow of air through radiator 18, the flow of air through an associated air conditioning condenser 54 is also improved. The condenser 54 is diagrammatically shown in FIG. 2 and is operatively mounted immediately in front of the radiator 18. Typically, condensers are rectangular in shape like a conventional radiator and therefore have comers which are outward of a circular fan 40 just like a rectangular radiator. The arrowed lines 56 illustrates flow of air through the condenser.
The graph shown in FIG. 6 represents engine cooling system performance with and without the improved fan shroud while the engine is idling which represents a difficult engine cooling condition. The plot A represents by the broken line the operational characteristics of the vehicle's cooling system with a conventional fan shroud without the corner vane structure of the subject fan shroud. As shown by plot A, the radiator coolant temperature rapidly begins to increase at time t-1 to a higher temperature level r-1. In many vehicles this increase in temperature initiates deactivation of the vehicle's air conditioning system by deactivating the compressor clutch. In plot A the air conditioner system of the vehicle is deactivated at about time t-2.
Plot B represents by the unbroken line the operation of the vehicle's cooling system with the subject improved fan shroud with the vane structure identified heretofore. With the improved shroud, the coolant temperature gradually increases from time t-1 until temperature level r-2 is reached. Note that temperature r-2 is cooler than temperature r-1. Also note that the air conditioning deactivation point is delayed from time t-2 to time t-3. The improved shroud accordingly provides greatly improved temperature management and improved air conditioner performance particularly while the vehicle is idling or moving slowly such as in stop and go traffic. The improved performance is manifested by area I between the two plots A and B.
While the invention has been shown and described by the preferred embodiment, it should be clear to those skilled in the art that various changes and modifications may be made thereto without departing from the scope of the following claims. | A shroud for a vehicle engine cooling fan mounted to a generally rectangular radiator that has fixed air guide vanes in strategic areas of the shroud outside of the periphery of the fan blades to direct and channel streams of peripheral air flowing through the corners of the radiator into these areas inward and in a swirling pattern into the fan blades and more particularly in a generally smooth and circuitous path counter to the direction of rotation of the fan and directly onto the pumping surfaces of the fan blades. This effectively feeds additional air into the fan and preloads the blades so that air pumping efficiency is resultantly improved and more air is moved through the radiator for improved heat exchange. | 5 |
The present invention relates to an improved method for brazing tubular parts in coaxial relationship with the bore of another part where one end of the tubular part nests with respect to the end of a second part.
BACKGROUND OF THE INVENTION
Where a cylindrical member rotates within a complementary cylindrical bore, the useful life of the parts can be extended by providing a counter sink at one of the bore into which is inserted a tubular, hardened wear ring. For example, machines used to cut hard surfaces such as concrete and asphalt have a rotatable cutting wheel with a plurality of cutting tools mounted on the wheel which are moved against a hard surface to advance the cut. Each of the cutting tools has a cylindrical shank which is rotatably mounted in a complementary cylindrical aperture in a mounting block. As disclosed in my co-pending application, Ser. No. 09/121,726 filed Jul. 24, 1998, the useful life of a tool and the mounting block can be extended by providing a tungsten carbide tubular insert at the forward end of the aperture in the mounting block or holder.
It is customary to use a braze to retain parts, such as a tubular insert fitted in a countersink at the end of a cylindrical aperture. The brazing process consists of providing a ring of braze material which is fitted between the inner surface of the countersink and the outer surface of tubular sleeve. The ring of braze material prevents the hardened ring from becoming seated within the countersink until the braze material is heated and melts, after which the ring can be forced into the countersink until it has become seated. After the parts cool, a substantial portion of the braze material should remain between the inner surface of the countersink and the outer surface of the insert to retain the parts in the assembled relationship. I have found, however, that when the braze material melts and a tubular insert is forced into a countersink most of the liquefied braze material flows into the cylindrical bore leaving an insufficient amount of braze material to retain the parts in the assembled relationship. When a tungsten carbide insert is brazed into a countersink around the bore of a tool block, as described above, it has been found that the braze will fail when the tool is subjected to the forces required to cut hard material such as concrete or asphalt.
An improved method is therefore needed for brazing of tubular parts in nested relationship in which a greater portion of braze material would be retained between the parts.
SUMMARY OF THE INVENTION
Briefly, the present invention is embodied in a method of assembling a tubular part in coaxial relationship with the bore of another part where the end of the tubular part nests with respect to the second part. For the purposes of this discussion, two parts are considered to be nest when the end of a first part is complimentary in shape to the end of a second part such that the outer surface of the first part will fit in near proximity to the complementary surface of the second part with the spacing between the surfaces being sufficient for retaining a brazing material. A tubular sleeve having an outer diameter sized to slide within a countersink surrounding the end of a cylindrical bore is an example of parts which can be assembled in nested relationship.
In accordance with the present invention, to braze a tubular part in nested relationship to a second part having a coaxial bore therein, a ring of braze material is provided where the ring has an inner diameter at least equal to the inner diameter of the tubular part, and an outer diameter which is no greater than the outer diameter of the tubular part. The parts are arranged in coaxial relationship with the ring of braze material and a viscous flux positioned between the complementarily shaped surfaces.
A tubular sleeve made of a soft metal material having an outer diameter which is a little larger than the inner diameter of the cylindrical bore is thereafter press fitted into the bore of both the block or holder and slip fitted into the bore of the insert. The assembled parts are thereafter heated, causing the braze material to melt, after which the parts are moved into nested relationship. As the parts are moved into nested relationship, the braze material is retained between the parts by the tubular sleeve fitting into the coaxial tubular bores of the parts.
When the parts are thereafter cooled, causing the braze material to harden, the parts will be retained in the assembled relationship. Thereafter, the soft metal of the tubular sleeve can be removed in a machining process. Following the removal of the tubular sleeve, the parts will be retained together by the braze remaining between them.
In a second embodiment of the invention, a body part can be made having a bore therein and a tubular member brazed into a countersink around one end of the bore. In this embodiment a body part blank for which the bore has not been made therein is provided with an annular recess in the surface thereof. The recess has an outer surface complimentary in shape to the outer surface of the tubular member and the inner surface of the recess forms a cylindrical stub having a diameter slightly less than the inner diameter of the bore of the completed body part. An annular piece of braze material is placed in the recess and the tubular member is positioned over the braze material, and the parts are heated to melt the braze material. After the parts cool the tubular member will be brazed into the countersink. Thereafter the cylindrical stub can be drilled and bored out to form the bore of the body part after which the tubular member will be in a countersink surrounding the bore.
BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the present invention will be had after a reading of the following detailed description taken in conjunction with the drawings where.
FIG. 1 is a cross sectional view of a mounting block having a cylindrical bore and a hardened metal wear ring into which a rotatable tool has been fitted;
FIG. 2 is an exploded view of the parts needed to braze the wear ring into the countersink surrounding the bore in the block;
FIG. 3 is a rear end view of the wear ring shown in FIG. 2;
FIG. 4 is a cross sectional view of the parts shown in FIG. 2, assembled prior to brazing;
FIG. 5 is a cross sectional view of the parts shown in FIG. 2 after the braze material has been melted;
FIG. 6 is a cross sectional view of the parts shown in FIG. 2 after the central sleeve has been machined out of the bore of the block;
FIG. 7 is an exploded cross sectional view of a partially manufactured tool body having a recess in the forward end thereof suitable for receiving a wear ring and a ring of braze material;
FIG. 8 shows the partially manufactured tool body shown in FIG. 7 with the wear ring brazed into the recess; and
FIG. 9 is a cross sectional view of the tool body shown in FIG. 7 after a bore has been drilled through the length thereof.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 and 3, a machine used to cut hardened material such as concrete has a plurality of mounting blocks 10 fitted around the circumference of wheel. Each mounting block 10 has a block body 12 with a cylindrical bore 14 extending from a forward surface 16 to a rear surface 18 . Fitted within a countersink 20 at the forward end of the bore 14 is a tubular tungsten carbide wear ring 22 having an outer surface 24 complementary in shape to the inner surface of the countersink 20 and a cylindrical bore 26 equal to or a little larger than the diameter of bore 14 , and a rear surface 25 . To provide room for braze material between the outer surface 24 of the wear ring and the inner surface of the countersink 20 a plurality of bumps 27 are spaced around the outer surface 24 of the wear ring 22 . Similarly, to space the rear surface 25 from the bottom surface of the countersink 20 , a second plurality of bumps 29 are spaced around the rear surface 25 of the wear ring 22 .
Fitted into the coaxial bores 14 , 26 of the block body 12 and the wear ring 22 is a cylindrical mounting portion 28 of a tool 30 having a tapered forward cutting end 32 . The wear ring 22 prevents the cylindrical bore 14 from becoming enlarged as the tool 30 is forced against a hard surface such as concrete or asphalt, however the wear ring 22 will become dislodged from the countersink 20 unless it is adequately retained by braze material between the parts.
Referring to FIGS. 2 to 6 , in accordance with the present invention, to retain the wear ring 22 within the countersink 20 of the block body 12 a split ring 34 of soft steel is provided having an outer diameter sized to fit snuggly within the bore 14 of the block body 12 and more loosely in the bore 26 of the wear ring 22 . A ring of brazing material 36 having a inner diameter larger than the inner diameter of the bore 14 and an outer diameter which is less than the inner diameter of the countersink 20 is fitting around the split ring 34 between the block body 12 and the wear ring 22 as shown in FIG. 4 . Thereafter, the parts are subjected to heat until the braze ring 36 melts, after which the wear ring 22 can be seated into the countersink 20 as shown in FIG. 5 .
After the parts are allowed to cool, hardened braze material will extend between the inner surfaces of all the parts and, in particular, a substantial portion of the braze material will remain between the outer surface 24 of the wear ring 22 and the countersink 20 . Thereafter the split ring 34 and any braze material adhering between the outer surface of the split ring 34 and the inner surface of the bores 14 , 26 can be machined away as shown in FIG. 6, and adequate braze material will remain between the parts to retain the parts in assembled relationship while the tool 30 is being used to cut a hardened surface, not shown.
In this embodiment the diameter of the bore 26 of the tungsten carbide wear ring 22 has been described as being a little larger than the diameter of the bore 14 of the block body 12 because tungsten carbide is brittle and is susceptible to becoming chipped while the split ring 34 is being machined out of the bore. By providing a bore 26 with a diameter which is a little larger than that of the block body 12 , the tungsten carbide will not become chipped while machining the split ring 34 away. It should be appreciated that the invention is usable to facilitate the brazing of many metal and even nonmetal materials, and whereas it is desireable that the bore of a tungsten carbide insert be a little larger than the diameter of the adjacent bore, a different relationship between the dementions of the parts may be desirable where different materials are involved.
It should be appreciated that the method of the present invention can be used to assemble any two parts which are to be retained in nested relationship with a coaxial bore of equal diameter extending between them. Specially, the method can be used to retain any two parts together where the parts having cylindrical bores of equal or nearly equal diameter and having complementary surfaces which fit together in nested relationship with bores thereof aligned in axial relationship to each other.
Referring to FIGS. 7 to 9 , a wear ring 40 having a cylindrical bore 42 , a frustoconical outer surface 44 and an annular forward and rear surfaces 46 , 48 respectively may be brazed into a countersink 58 in the forward end of a tool body 52 to surround one end of a cylindrical bore 54 in accordance with the second embodiment of the invention.
In accordance with this embodiment, prior to forming the bore 54 , an annular recess 56 is formed in the forward end of the tool body 52 , the recess having an outer wall 58 complementary in shape to frustoconical outer surface 44 of the wear ring 40 . The annular recess 56 also leaves a cylindrical stub 60 , the diameter of which is equal to or a little smaller than the inner diameter of the bore 42 of the wear ring 40 .
As shown in FIG. 7, a ring of braze material 62 is placed within the recess 56 and around the stub 60 , and then the wear ring 40 is fitted within the recess 56 on top of the ring of braze material 62 . Preferably, the wear ring 40 has a plurality of protrusions 64 — 64 on the frustoconical surfaces thereof and has a second plurality of protrusions 65 — 65 on the rearward surface 48 on the outer surface thereof to space the surfaces of the ring 40 from the surface of the recess 56 in the tool body 52 . Heat is then applied to the parts causing the braze material 62 to melt and flow between the surfaces of the recess 56 and the surfaces of the ring 40 and after it has cooled, the ring 40 will be securely bonded into the recess 56 as shown in FIG. 8 .
After the ring 40 has been brazed into the recess 56 the tool body 52 can be placed into a lathe or other suitable tool for drilling and boring the bore 54 through the length of the tool body 52 to achieve the completed tool body shown in FIG. 9 . The outer surface of the recess 56 defines the outer wall of the countersink 50 of the completed tool body 52 .
While the invention has been described with respect to two embodiments, it will be appreciated that many modifications and variations may be made without departing from the true spirit and scope of the invention. It is therefore the intent of the appendent claims to cover such modifications and variations which fall within the true spirit and scope of the invention. | A tubular part is brazed into coaxial relationship with the bore of a second part having a counter bore for receiving the tubular part by providing a tubular sleeve within the bores of the two parts prior to brazing. After the braze material has cooled the tubular sleeve and any braze material around it is machined out of the bores. In a second embodiment a tubular part is brazed into a recess of the second part before a bore is drilled therein. After the parts are brazed together the bore is drilled through both the tubular part and the second part. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority to and the benefit of Korean Patent Application No. 10-2015-0170986 filed on Dec. 2, 2015, the entire contents of which is incorporated herein for all purposes by this reference.
BACKGROUND OF THE INVENTION
[0002] Field of the Invention
[0003] The present invention relates to an automatic transmission for a vehicle.
[0004] Description of Related Art
[0005] Recent increases in oil prices are triggering hard competition in enhancing fuel consumption of a vehicle.
[0006] In this sense, research on an engine has been undertaken to achieve weight reduction and to enhance fuel consumption by so-called downsizing and research on an automatic transmission has been performed to simultaneously provide better drivability and fuel consumption by achieving more shift stages.
[0007] In order to achieve more shift stages for an automatic transmission, the number of parts is typically increased, which may deteriorate installability, production cost, weight and/or power flow efficiency.
[0008] Therefore, in order to maximally enhance fuel consumption of an automatic transmission having more shift stages, it is important for better efficiency to be derived by a smaller number of parts.
[0009] In this respect, an eight-speed automatic transmission has been recently introduced, and a planetary gear train for an automatic transmission enabling more shift stages is under investigation.
[0010] Considering that gear ratio spans of recently developed eight-speed automatic transmissions are typically between 6.5 and 7.5, fuel consumption enhancement is not very large.
[0011] In the case of a gear ratio span of an eight-speed automatic transmission having a level above 9.0, it is difficult to maintain step ratios between adjacent shift stages to be linear, by which driving efficiency of an engine and drivability of a vehicle deteriorated.
[0012] Thus, research studies are underway for developing a high efficiency automatic transmission having nine or more speeds.
[0013] The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.
BRIEF SUMMARY
[0014] Various aspects of the present invention are directed to providing a planetary gear train of an automatic transmission for a vehicle having advantages of, by minimal complexity, realizing at least forward ninth speeds and at least one reverse speed, increasing a gear ratio span so as to improve power delivery performance and fuel consumption, and achieving linearity of shift stage step ratios.
[0015] An exemplary planetary gear set according to an embodiment includes
[0016] an input shaft for receiving an engine torque, an output shaft for outputting a shifted torque, a first planetary gear set having first, second, and third rotational elements, a second planetary gear set having fourth, fifth, and sixth rotational elements, a third planetary gear set having seventh, eighth, and ninth rotational elements, a fourth planetary gear set having tenth, eleventh, and twelfth rotational elements, and six control elements for selectively interconnecting the rotational elements.
[0017] The input shaft may be continuously connected with the third rotational element,
[0018] The output shaft may be continuously connected with the eleventh rotational element,
[0019] The first rotational element may be continuously connected with the fourth rotational element,
[0020] The second rotational element may be continuously connected with the eighth rotational element and twelfth rotational element,
[0021] The fifth rotational element may be continuously connected with the tenth rotational element. The sixth rotational element may be continuously connected with the seventh rotational element.
[0022] The first rotational element may be selectively connectable with the eleventh rotational element. The second rotational element may be selectively connectable with the third rotational element. The sixth rotational element may be selectively connectable with the ninth rotational element. The fifth rotational element may be selectively connectable with the transmission housing. The sixth rotational element may be selectively connectable with the transmission housing. The ninth rotational element may be selectively connectable with the transmission housing.
[0023] The first, second, and third rotational elements of the first planetary gear set may respectively be a sun gear, a planet carrier, and a ring gear of the first planetary gear set. The fourth, fifth, and sixth rotational elements of the second planetary gear set may respectively be a sun gear, a planet carrier, and a ring gear of the second planetary gear set. The seventh, eighth, and ninth rotational elements of the third planetary gear set may respectively be a sun gear, a planet carrier, and a ring gear of the third planetary gear set. The tenth, eleventh, and twelfth rotational elements of the fourth planetary gear set may respectively be a sun gear, a planet carrier, and a ring gear of the fourth planetary gear set.
[0024] A planetary gear train according to an exemplary embodiment of the present invention may realize at least forward ninth speeds and at least one reverse speed formed by operating the four planetary gear sets as simple planetary gear sets by controlling six control elements.
[0025] In addition, a planetary gear train according to an exemplary embodiment of the present invention may realize a gear ratio span of more than 8.7, thereby maximizing efficiency of driving an engine.
[0026] In addition, the linearity of step ratios of shift stages is secured while multi-staging the shift stage with high efficiency, securing linearity of step ratios of shift stages, thereby making it possible to improve drivability such as acceleration before and after a shift, an engine speed rhythmic sense, and the like.
[0027] Further, effects that can be obtained or expected from exemplary embodiments of the present invention are directly or suggestively described in the following detailed description. That is, various effects expected from exemplary embodiments of the present invention will be described in the following detailed description.
[0028] The methods and apparatuses of the present invention have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description, which together serve to explain certain principles of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1 is a schematic diagram of a planetary gear train according to an exemplary embodiment of the present invention.
[0030] FIG. 2 is an operational chart for respective control elements at respective shift stages in a planetary gear train according to an exemplary embodiment of the present invention.
[0031] It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment.
[0032] In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing.
DETAILED DESCRIPTION
[0033] Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that the present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims.
[0034] The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.
[0035] The drawings and description are to be regarded as illustrative in nature and not restrictive, and like reference numerals designate like elements throughout the specification.
[0036] In the following description, dividing names of components into first, second, and the like is to divide the names because the names of the components are the same as each other and an order thereof is not particularly limited.
[0037] FIG. 1 is a schematic diagram of a planetary gear train according to an exemplary embodiment of the present invention.
[0038] Referring to FIG, a planetary gear train according to an exemplary embodiment of the present invention includes first, second, third, and fourth planetary gear sets PG 1 , PG 2 , PG 3 , and PG 4 arranged on a same axis, an input shaft IS, an output shaft OS, seven connecting members TM 1 to TM 7 for interconnecting rotational elements of the first, second, third, and fourth planetary gear sets PG 1 , PG 2 , PG 3 , and PG 4 , six control elements C 1 to C 3 and B 1 to B 3 , and a transmission housing H.
[0039] Torque input from the input shaft IS is shifted by cooperative operation of the first, second, third, and fourth planetary gear sets PG 1 , PG 2 , PG 3 , and PG 4 , and then output through the output shaft OS.
[0040] The simple planetary gear sets are arranged in the order of first, first, third, second, fourth planetary gear sets (PG 1 , PG 3 , PG 2 , PG 4 ), from an engine side.
[0041] The input shaft IS is an input member and the torque from a crankshaft of an engine, after being torque-converted through a torque converter, is input into the input shaft IS.
[0042] The output shaft OS is an output member, and being arranged on a same axis with the input shaft IS, delivers a shifted torque to a drive shaft through a differential apparatus.
[0043] The first planetary gear set PG 1 is a single pinion planetary gear set, and includes a first sun gear S 1 , a first planet carrier PC 1 that supports a first pinion P 1 externally engaged with the first sun gear S 1 , and a first ring gear R 1 internally engaged with the first pinion P 1 . The first sun gear S 1 acts as a first rotational element N 1 , the first planet carrier PC 1 acts as a second rotational element N 2 , and the first ring gear R 1 acts as a third rotational element N 3 .
[0044] The second planetary gear set PG 2 is a single pinion planetary gear set, and includes a second sun gear S 2 , a second planet carrier PC 2 that supports a second pinion P 2 externally engaged with the second sun gear S 2 , and a second ring gear R 2 internally engaged with the second pinion P 2 . The second sun gear S 2 acts as a fourth rotational element N 4 , the second planet carrier PC 2 acts as a fifth rotational element N 5 , and the second ring gear R 2 acts as a sixth rotational element N 6 .
[0045] The third planetary gear set PG 3 is a single pinion planetary gear set, and includes a third sun gear S 3 , a third planet carrier PC 3 that supports a third pinion P 3 externally engaged with the third sun gear S 3 , and a third ring gear R 3 internally engaged with the third pinion P 3 . The third sun gear S 3 acts as a seventh rotational element N 7 , the third planet carrier PC 3 acts as an eighth rotational element N 8 , and the third ring gear R 3 acts as a ninth rotational element N 9 .
[0046] The fourth planetary gear set PG 4 is a single pinion planetary gear set, and includes a fourth sun gear S 4 , a fourth planet carrier PC 4 that supports a fourth pinion P 4 externally engaged with the fourth sun gear S 4 , and a fourth ring gear R 4 internally engaged with the fourth pinion P 4 . The fourth sun gear S 4 acts as a tenth rotational element N 10 , the fourth planet carrier PC 4 acts as an eleventh rotational element N 11 , and the fourth ring gear R 4 acts as a twelfth rotational element N 12 .
[0047] In the arrangement of the first, second, third, and fourth planetary gear sets PG 1 , PG 2 , PG 3 , and PG 4 , the first rotational element N 1 is directly connected with the seventh rotational element N 7 , the second rotational element N 2 is directly connected with the fifth rotational element N 5 and the twelfth rotational element N 12 , and the fourth rotational element N 4 is directly connected with the ninth rotational element N 9 , the eighth rotational element N 8 is directly connected with tenth rotational element N 10 , by seven connecting members TM 1 to TM 7 .
[0048] The seven connecting members TM 1 to TM 7 are arranged as follows.
[0049] The first connecting member TM 1 is connected with the first rotational element N 1 (first sun gear S 1 ) and the fourth rotational element N 4 (second sun gear S 2 ).
[0050] The second connecting member TM 2 is connected with the second rotational element N 2 (first planet carrier PC 1 ) and eighth rotational element N 8 (third planet carrier PC 3 ) and the twelfth rotational element N 12 (fourth ring gear R 4 ).
[0051] The third connecting member TM 3 is connected with the third rotational element N 3 (first ring gear R 1 ), directly connected with the input shaft IS thereby continuously acting as an input element, and selectively connectable with the second connecting member TM 2 .
[0052] The fourth connecting member TM 4 is connected with the fifth rotational element N 5 (second planet carrier PC 2 ) and the tenth rotational element N 10 (fourth sun gear S 4 ), and selectively connectable with the transmission housing H thereby acting as a selective fixed element.
[0053] The fifth connecting member TM 5 is connected with the sixth rotational element N 6 (second ring gear R 2 ) and the seventh rotational element N 7 (third sun gear S 3 ), and selectively connectable with the transmission housing H, thereby acting as a selective fixed element.
[0054] The sixth connecting member TM 5 is connected with the ninth rotational element N 9 (third ring gear R 3 ), selectively connectable with the transmission housing H thereby acting as a selective fixed element, and selectively connectable with the fifth connecting member TM 5 .
[0055] The seventh connecting member TM 7 is connected with the eleventh rotational element N 11 (fourth planet carrier PC 4 ), selectively connectable with the first connecting member TM 1 , and directly connected with the output shaft OS thereby continuously acting as an output element.
[0056] The connecting members TM 1 to TM 7 may be selectively interconnected with one another by control elements of three clutches C 1 , C 2 , and C 3 .
[0057] , The connecting members TM 1 to TM 7 may be selectively connectable with the transmission housing H, by control elements of three brakes B 1 , B 2 , and B 3 .
[0058] The six control elements C 1 to C 3 and B 1 to B 3 are arranged as follows.
[0059] The first clutch C 1 is arranged between the first connecting member TM 1 and the seventh connecting member TM 7 , such that the first connecting member TM 1 and the seventh connecting member TM 7 may selectively become integral.
[0060] The second clutch C 2 is arranged between the second connecting member TM 2 and the third connecting member TM 3 , such that the second connecting member TM 2 and the third connecting member TM 3 may selectively become integral.
[0061] The third clutch C 3 is arranged between the fifth connecting member TM 5 and the sixth connecting member TM 6 , such that the fifth connecting member TM 5 and the sixth connecting member TM 6 may selectively become integral.
[0062] The first brake B 1 is arranged between the fourth connecting member TM 4 and the transmission housing H, such that the fourth connecting member TM 4 may selectively act as a fixed element.
[0063] The second brake B 2 is arranged between the fifth connecting member TM 5 and the transmission housing H, such that the fifth connecting member TM 5 may selectively act as a fixed element.
[0064] The third brake B 3 is arranged between the sixth connecting member TM 6 and the transmission housing H, such that the sixth connecting member TM 6 may selectively act as a fixed element.
[0065] The control elements of the first, second, and third clutches C 1 , C 2 , and C 3 and the first, second, and third brakes B 1 , B 2 , and B 3 may be realized as multi-plate hydraulic pressure friction devices that are frictionally engaged by hydraulic pressure.
[0066] FIG. 2 is an operational chart for respective control elements at respective shift stages in a planetary gear train according to an exemplary embodiment of the present invention.
[0067] As shown in FIG. 2 , a planetary gear train according to an exemplary embodiment of the present invention performs shifting by operating two control elements at respective shift stages.
[0068] In the forward first speed shift stage D 1 , the first and third brakes B 1 and B 3 are simultaneously operated. As a result, torque of the input shaft IS is input to the third connecting member TM 3 , and the fourth connecting member TM 4 and the sixth connecting member TM 6 simultaneously act as fixed elements by the operation of the first and third brakes B 1 and B 3 , thereby realizing the forward first speed by cooperative operation of respective connecting members and outputting a shifted torque through the output shaft OS connected with the seventh connecting member TM 7 .
[0069] In the forward second speed shift stage D 2 , the third clutch C 3 and the first brake B 1 are simultaneously operated. As a result, torque of the input shaft IS is input to the third connecting member TM 3 , and the fifth connecting member TM 5 becomes integral with the sixth connecting member TM 6 by the operation of the third clutch C 3 . In addition, the fourth connecting member TM 4 acts as a fixed element by the operation of the first brake B 1 , thereby realizing the forward second speed by cooperative operation of respective connecting members and outputting a shifted torque through the output shaft OS connected with the seventh connecting member TM 7 .
[0070] In the forward third speed shift stage D 3 , the first and second brakes B 1 and B 2 are simultaneously operated. As a result, torque of the input shaft IS is input to the third connecting member TM 3 , the fourth connecting member TM 4 and the fifth connecting member TM 5 simultaneously act as fixed elements by the operation of the first and second brakes B 1 and B 2 , thereby realizing the forward third speed by cooperative operation of respective connecting members and outputting a shifted torque through the output shaft OS connected with the seventh connecting member TM 7 .
[0071] In the forward fourth speed shift stage D 4 , the first clutch C 1 and the first brake B 1 are simultaneously operated. As a result, torque of the input shaft IS is input to the third connecting member TM 3 , and the first connecting member TM 1 becomes integral with the seventh connecting member TM 7 by the operation of the first clutch C 1 . In addition, the fourth connecting member TM 4 acts as a fixed element by the operation of the first brake B 1 , thereby realizing the forward fourth speed by cooperative operation of respective connecting members and outputting a shifted torque through the output shaft OS connected with the seventh connecting member TM 7 .
[0072] In the forward fifth speed shift stage D 5 , the first clutch C 1 and the second brake B 2 are simultaneously operated. As a result, torque of the input shaft IS is input to the third connecting member TM 3 , and the first connecting member TM 1 becomes integral with the seventh connecting member TM 7 by the operation of the first clutch C 1 . In addition, the fifth connecting member TM 5 acts as a fixed element by the operation of the second brake B 2 , thereby realizing the forward fifth speed by cooperative operation of respective connecting members and outputting a shifted torque through the output shaft OS connected with the seventh connecting member TM 7 .
[0073] In the forward sixth speed shift stage D 6 , the second clutch C 2 and the second brake B 2 are simultaneously operated. As a result, torque of the input shaft IS is input to the third connecting member TM 3 , and the second connecting member TM 2 becomes integral with the third connecting member TM 3 by the operation of the second clutch C 2 . In addition, the fifth connecting member TM 5 acts as a fixed element by the operation of the second brake B 2 , thereby realizing the forward sixth speed by cooperative operation of respective connecting members and outputting a shifted torque through the output shaft OS connected with the seventh connecting member TM 7 .
[0074] In the forward seventh speed shift stage D 7 , the first and second brakes C 1 and C 2 are simultaneously operated. As a result, torque of the input shaft IS is input to the third connecting member TM 3 , and the first planetary gear set PG 1 becomes integral by the operation of the second clutch C 2 . In addition, the first connecting member TM 1 becomes integral with the seventh connecting member TM 7 by the operation of the first clutch C 1 , thereby realizing the forward seventh speed and outputting an inputted torque through the output shaft OS connected with the seventh connecting member TM 7 .
[0075] In the forward eighth speed shift stage D 8 , the second clutch C 2 and the third brake B 3 are simultaneously operated. As a result, torque of the input shaft IS is input to the third connecting member TM 3 , and the second connecting member TM 2 becomes integral with the third connecting member TM 3 by the operation of the second clutch C 2 . In addition, the sixth connecting member TM 6 acts as a fixed element by the operation of the third brake B 3 , thereby realizing the forward eighth speed by cooperative operation of respective connecting members and outputting a shifted torque through the output shaft OS connected with the seventh connecting member TM 7 .
[0076] In the forward ninth speed shift stage D 9 , the first clutch C 1 and the third brake B 3 are simultaneously operated. As a result, torque of the input shaft IS is input to the third connecting member TM 3 , and the first connecting member TM 1 becomes integral with the seventh connecting member TM 7 by the operation of the first clutch C 1 . In addition, the sixth connecting member TM 6 acts as a fixed element by the operation of the third brake B 3 , thereby realizing the forward ninth speed by cooperative operation of respective connecting members and outputting a shifted torque through the output shaft OS connected with the seventh connecting member TM 7 .
[0077] In the reverse speed REV, the second and the third brakes B 2 and B 3 are simultaneously operated. As a result, torque of the input shaft IS is input to the third connecting member TM 3 , and the fifth connecting member TM 5 and the sixth connecting member TM 6 simultaneously act as fixed elements by the operation of the second and the third brakes B 2 and B 3 , thereby realizing the reverse speed by cooperative operation of respective connecting members and outputting a shifted torque through the output shaft OS connected with the seventh connecting member TM 7 .
[0078] As described above, a planetary gear train according to an exemplary embodiment of the present invention may realize the forward nine speeds and one reverse speed formed by operating the four planetary gear sets PG 1 , PG 2 , PG 3 , and PG 4 by controlling three clutches C 1 , C 2 , and C 3 and three brakes B 1 , B 2 , and B 3 .
[0079] In addition, a planetary gear train according to an exemplary embodiment of the present invention may realize a gear ratio span of more than 8.7, thereby maximizing efficiency of driving an engine.
[0080] In addition, the linearity of step ratios of shift stages is secured while multi-staging the shift stage with high efficiency, thereby making it possible to improve drivability such as acceleration before and after a shift, an engine speed rhythmic sense, and the like.
[0081] For convenience in explanation and accurate definition in the appended claims, the terms “upper”, “lower”, “inner” and “outer” are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures.
[0082] The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents. | Nine or more forward speeds and at least one reverse speed are achieved by a planetary gear train of an automatic transmission for a vehicle including an input shaft, an output shaft, four planetary gear sets respectively having three rotational elements, and six control elements for selectively interconnecting the rotational elements. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates to underwater lighting technology. It is particularly applicable, but in no way limited, to a submersible lighting device or lamp.
BACKGROUND TO THE INVENTION
[0002] Lamps for underwater use are available for various applications. One such application is for illuminating the water around a landing stage or jetty at night. Use of underwater lamps in this application has a number of uses and advantages. They can be a safety feature, by improving visibility in that area. They can be an aesthetic feature, but importantly they can also be used to attract fish. It will be appreciated that this fish-attracting application can be used not only near to or around a landing stage, but anywhere where there is access to a suitable electricity supply. This can include use from a boat or yacht with an electrical generator. This type of use results in a number of inherent problems. Firstly, the lamp must be secured in some way, either on the sea or river bed near the jetty or near a boat, or to supporting pilework associated with the jetty itself. Seabeds or riverbeds close to the shore are generally very soft due to the deposit of sediment or sand. As a consequence, the stable location of a lamp is problematic. This situation is made worse by motorboat traffic passing over the lights, sometimes at speed, creating a considerable wash or wake which can dislodge a light sitting on the bottom.
[0003] An alternative is to affix the lamp to pilework under the jetty, but this may also be problematic since piles can have a number of different profiles.
[0004] In addition, it is necessary to be able to change a blown bulb quickly or easily. Some prior art submersible lamps are “sealed for life” units, where a waterproof seal around the bulb is formed by setting the bulb itself in concrete or a resin. Whilst this may be a cost-effective form of construction initially, the unit must be scrapped if the bulb blows.
[0005] It is an object of the present invention to overcome or at least mitigate some or all of the problems mentioned above.
SUMMARY OF THE INVENTION
[0006] According to the present invention there is provided a submersible light assembly comprising:
[0007] (i) at least one light source;
[0008] (ii) a watertight housing having a base, at least one sidewall and a transparent envelope enclosing a portion of the light source;
[0009] wherein at least a portion of an outer face of the base of the housing is profiled to substantially conform to the profile of the surface profile of pilework of the type associated with a jetty. By shaping the base in this way, and as described below, it facilitates securing the light to the underwater structure of a jetty.
[0010] Preferably a portion of the base is curved, preferably in a concave shape. Very often the pilework associated with a jetty is circular in cross-section and a concave, indented shape in the base makes for an easier and more secure fixing.
[0011] Preferably the base incorporates two concave indentations set substantially orthogonal to each other. This arrangement means that the light assembly can be positioned in one of four possible configurations. In this way the power supply cable to the light assembly can be positioned in a convenient orientation.
[0012] Preferably the assembly further comprises a support bracket adapted to be secured to pilework and to partially take the weight of the light assembly. Having a separate bracket means that this can be secured to the pilework during the installation, at the appropriated depth, to take a portion of the weight of the assembly, both during and after installation.
[0013] Preferably the assembly further comprises a cable entry point adapted to form a waterproof seal between an electrical cable or conduit and the assembly.
[0014] In a particularly preferred embodiment the support bracket is so sized and shaped to be adapted to engage with the cable entry point in order to partially support the lamp assembly in use.
[0015] Preferably the assembly housing further comprising eyelets adapted to accommodate one or more straps to strap the light assembly to a pile. Tightly strapping the light assembly to pilework is a preferred method of fixing the assembly under water.
[0016] In a particularly preferred embodiment the assembly further comprises a demountable ground engaging spike, and wherein the demountable ground-engaging spike is secured to the base of the light assembly using spike securing means. This provides an alternative means of securing the light assembly in place, this time on the sea or riverbed. Downward pressure on the light assembly drives the spike into the bed and the spike anchors it there.
[0017] Preferably said housing comprises a base, a body portion and said transparent envelope with sealing gaskets between adjacent components.
[0018] Preferably said base incorporates a weight. Because there must be space between the transparent envelope and the light source, and around the electrical components within the housing, additional weight is needed to reduce the natural buoyancy of the assembly when submerged.
[0019] According to a further embodiment of the present invention there is provided a submersible light assembly comprising at least one light source, a watertight housing having a base, at least one sidewall and a transparent envelope enclosing a portion of the light source; and a demountable ground engaging spike. The feature of a demountable spike, secured to the assembly by securing means, can be employed without the need to incorporate a profiled base. The features described above, and in the description below, in respect of a first embodiment of the invention can be applied equally well to this second embodiment.
[0020] According to a yet further embodiment, there is provided a submersible light assembly comprising at least one light source, a watertight housing having a base, at least one sidewall and a transparent envelope enclosing a portion of the light source, and eyelets adapted to accommodate one or more straps to strap the light and assembly to a pile of the type associated with a jetty.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The present invention will now be described, by way of example only, with reference to the following drawings wherein:
[0022] FIG. 1 shows a light assembly according to the present invention with the bulb cover removed;
[0023] FIGS. 2 , 3 and 4 show side, top and bottom elevations of an assembled light assembly of FIG. 1 ;
[0024] FIG. 5 shows a cross-section through the light assembly of FIG. 1 ;
[0025] FIGS. 6A to C show bottom, side and top elevations of an upper part of the housing of a light assembly;
[0026] FIGS. 7A to C show bottom, side and top elevations of a base portion of a housing of a light assembly;
[0027] FIGS. 8A and B show a side and bottom elevations of a ground engaging spike;
[0028] FIG. 9 shows a sealing gasket for a bulb cover;
[0029] FIG. 10 shows a sealing gasket for the waterproof joint between the upper part and the base part of a housing;
[0030] FIG. 11 shows detail ‘A’ from FIG. 10 ;
[0031] FIG. 12 shows a lifting eye;
[0032] FIGS. 13 , 14 and 15 show various elevations of a support bracket;
[0033] FIG. 16 shows various installation options;
[0034] FIG. 17 shows the ground engaging spike and its connection to the base of the light assembly;
[0035] FIG. 18 shows a support bracket engaged around a cable entry point.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0036] Preferred embodiments will now be described by way of example only. They are not the only way the invention can be put into practice but they are the best ways currently known to the applicant.
[0037] Referring to FIGS. 1 to 4 , these show various elevation views of a first embodiment of the submersible lamp assembly. They show a substantially watertight housing assembly consisting of a base portion 19 , an upper portion of the housing 13 , a bulb or lamp 2 and a transparent envelope or lamp cover 1 . A flange ring 33 , held in place by a number of nuts, bolts and washers, acts to compress the lamp cover against a fluid-tight sealing gasket, shown in more detail in FIG. 9 .
[0038] A similar, but larger fluid-tight gasket, shown in FIG. 10 , is positioned between the base portion and the upper portion of housing, also held in place by a plurality of nuts, bolts and washers.
[0039] It will be seen from these figures, the base portion is substantially circular cylindrical with a continuous side wall and a closed end wall. Other than the open top end to the cylinder, which is flanged to form a good fluid-tight seal with upper portion, the only other penetration into the base portion is fluid-tight cable gland 16 containing a bush 17 , shown in FIG. 5 . This allows an electrical supply cable to enter the base in a fluid-tight manner.
[0040] Similarly the upper portion of the housing is substantially circular cylindrical with a flange at its lower end to mate with the base portion and a smaller diameter flange at its upper end to mate with the bulb cover.
[0041] Referring to FIG. 5 , it will be seen that base portion contains a ballast weight 20 , secured in place by a bolt 22 and spread washer 23 . The weight has a cutout or channel 32 to allow an unrestricted route for the supply cable from the cable gland to the upper part of the housing. This upper part houses the electrical components and circuitry necessary to make the lamp function. These include a ballast 12 and capacitor 11 , a ceramic lamp holder or bulb holder 10 held in place by a bracket 9 . Also attached to the upper portion is an eyelet bolt 29 , shown in more detail in FIG. 12 . This enables the light assembly to be raised and lowered into position.
[0042] A key feature of the present invention relates to the provisions made to install the light assembly safely and securely. Firstly, a demountable ground-engaging spike 40 is provided, as shown in FIG. 8 . This consists of a mounting plate 41 A, designed to bolt onto the bottom of the base at a central point. The shaft of the spike 41 is formed from struts 42 to 45 arranged at right angles to each other in a crucifix form, and narrowing towards the tip region 46 . The tip region has a similar form of construction and forms an arrowhead type of arrangement at the ground-engaging end of the spike, with shoulders 47 preventing easy removal of the spike, once it has been sunk into the ground.
[0043] A further view of a ground-engaging spike, and its method of connection to the base of a light assembly, is shown in FIG. 17 . A corresponding numbering system to that used in FIGS. 1 to 5 and 8 is used in FIG. 17 . The base of the spike 41 A is formed in the shape of a substantially flat flange. This flange engages into a correspondingly shaped recess 56 in the base 19 . Apertures 55 , 57 are provided in the flange 41 A to accommodate bolts 53 , 54 . These bolts, four in total in this example, act as securing means to secure the spike 41 to the base 19 . Corresponding threaded holes in the base are provided to accommodate these bolts. It follows therefore that the light assemblies of the present invention can be used with, or without, a ground engaging spike depending on the requirements of the installation.
[0044] The spike is demountable in order that the light assembly may also be secured directly to some underwater structure such as a pile or post, such as those used to support a jetty or deck. To facilitate this, the bottom of the base is profiled, in this case the base is concave in shape, as shown at 51 in FIG. 5 and 51 and 52 in FIG. 1 . Preferably two concave shaped indentations are formed in the base bottom set at right angles to each other. In this way the light assembly can be placed against a circular pile in any one of 4 configurations. This is shown in FIG. 1 and ensures that the direction in which the electrical supply cable, which is both heavy and relatively inflexible, can be arranged to suit each particular installation.
[0045] To facilitate installation against a post, a separate bracket 18 is provided as shown in FIGS. 13 , 14 and 15 . One face of the bracket 61 has a radius which corresponds to the radius of the base. In this way it fits snugly against the face of the circular cylindrical base body when in use. Extending away from the curved face, substantially at right angles is a face 62 containing two fixing holes 63 , 64 . These holes are used to attach this face of the bracket to the pilework at the appropriate depth below the water. Face 62 is also curved, in this case of a radius to match that in the concave depressions in the bottom of the base portion. This leads to a snug, secure fit against the pilework.
[0046] A further feature of this bracket is a semi-circular cut out 65 in the face 61 which is in contact with the side of the base. This cut out fits around the cable gland 16 and acts to both locate and stabilize the assembly during and after installation. Sides of the bracket 66 , 67 stretching between the two faces at right angles complete the bracket arrangement and add the necessary strength.
[0047] FIG. 18 shows a perspective view of a bracket 18 in position against the side of the base of a light assembly, nested around a cable gland 16 . This illustrates the neatness of this type of fixing method.
[0048] Two methods of installation are shown in FIG. 16 . In FIG. 16A the light assembly, with spike attached, is lowered from a boat and the spike sinks into or is driven into the sea or riverbed in the desired position.
[0049] In FIG. 16C the light assembly is offered up to a pile or post below the water at the appropriate depth. A strap 70 is offered around the post and threaded through two of the eyelets 34 , 35 , 36 shown in FIG. 3 . Pulling strap 70 tight secures the light assembly to the post. Bracket 18 is then offered up to the post and light assembly, slipped around the cable gland and secured in place to the post. This helps to take the weight of the light assembly and complete the installation.
[0050] Whilst a circular cylindrical light assembly has been described in this embodiment it will be appreciated that any substantially cylindrical form will work equally well and also that it is not even necessary for the assembly to be cylindrical in form.
[0000]
TABLE 1
KEY TO FIG. 5
Reference
Numeral
Designation
Number
Material
32
31
Ground spike
1
ABS
29
Eyelet bolt M8
1
Stainless Steel
28
Hex. Nut M4
4
27
Ballast bracket
1
Iron Plate
26
Round head bolt M5 × 10
4
25
Round head bolt M4 × 55
4
24
Body seal
1
Silicone
23
Washer
1
22
Hex. Bolt M10 × 65
1
21
Gasket
1
Silicone
20
Loader
1
19
Bottom lamp body
1
PSU
18
Support bracket
1
17
Bush
1
16
Cable gland
1
15
Hex. Nut M8
12
14
Allen screw bolt M8 × 25
12
13
Top lamp body
1
12
250 W ballast
1
11
18UF capacitor
1
10
Lamp holder bolt
2
9
Lamp holder bracket
1
8
Ceramic lamp holder
1
7
Round head bolt M5 × 10
2
6
Glass shade seal
1
Silicone
5
Washer
1
PSU
4
Butterfly nut M8 × 1.25
6
POM
3
Bolt
6
Stainless Steel
2
250 W Hg lamp
1
1
Glass shade
1
Toughened glass | A submersible light assembly comprising:
(i) at least one light source;
(ii) a watertight housing having a base, at least one sidewall and a transparent envelope enclosing a portion of the light source;
wherein at least a portion of an outer face of the base of the housing is curved to substantially conform to the profile of the circumference of pilework of the type associated with a jetty. | 5 |
This is a continuation of application Ser. No. 414,215, filed Nov. 9, 1973, now abandoned.
BACKGROUND
1. Field of the Invention
The present invention relates to storage elements and, more particularly, to storage elements incorporating field effect transistors produced by means of MOS techniques.
2. The Prior Art
Storage arrays incorporating multiple storage cells constructed by means of MOS techniques are well known. Some of these arrays incorporate a single transistor element for each storage cell, and one arrangement of this kind is illustrated in German patent application P 21 48 948.5, which, in FIG. 4, illustrates a plan view of a storage array incorporating an individual field effect transistor and a capacitor for each storage cell. The electrical connections with the gate electrodes of each field effect transistor are established at a location remote from the channel zone of the field effect transistor. It is desirable, if possible, to increase the packing density of the storage cells within such an array by relocating some of the electrical connections.
SUMMARY OF THE PRESENT INVENTION
It is a principal object of the present invention to provide an integrated circuit incorporating a plurality of storage cells in which the packing density of such cells is increased beyond that heretofore known.
This and other objects and advantages of the present invention will become manifest by an examination of the following description and the accompanying drawings.
In one embodiment of the present invention, there is provided a substrate supporting a plurality of field effect transistors, each having a capacitor for together forming an individual storage cell, and conductive means for providing contact with the gate electrodes of a plurality of the transistors, such conductive means being disposed in a plane spaced from the plane of the transistors and overlapping the channel zones of the transistors.
BRIEF DESCRIPTION OF THE DRAWINGS
Reference will now be made to the accompanying drawings, in which:
FIG. 1 is a cross-sectional illustration of an integrated circuit constructed in accordance with the present invention;
FIG. 2 is a plan view of the circuit of FIG. 1; and
FIG. 3 is a plan view of a portion of a storage arrangement incorporating a plurality of circuits like those of FIGS. 1 and 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, a semiconductor substrate 1 is provided which, in one example, is n-conducting silicon. The substrate 1 contains diffusion zones 2 and 3, which are doped with p-conductive material. The diffusion zone 3 represents the source zone of a field effect transistor (or FET), and the zone 2 represents the drain zone of the FET. The zone 8 between the zones 2 and 3 is referred to as the "channel zone" of the FET.
Instead of employing n-conductive material for the substrate 1, it is possible to use a substrate with a layer of n-conductive semi-conductive material arranged thereon, for example, by epitaxially growing the n-conductive layer. Alternatively, either a p-conductive substrate 1 may be employed, in which case the zones 2 and 3 are doped with n-conductive material, or a p-conductive layer may be provided on another substrate, as is well known in the art. The present invention does not require the use of a substrate of any particular construction or conductivity.
On top of the surface of the substrate 1, and also on top of the zones 2 and 3, a layer 4 of electrically insulating material is applied. The layer 4 is preferably silicon dioxide. On top of the layer 4, opposite a location adjacent the zone 2, an electrically conductive coating 6 is applied, which forms a first conductive path. The coating 6 forms one electrode of a capacitor which is electrically connected to the zone 2 of the FET. The second electrode of this capacitor is the inversion layer 66, which forms beneath the electrode 6 in the semiconductor substrate 1 when voltage is applied between the coating 6 and the substrate 1. A conductor 61 is provided in electrical contact with the coating 6, and a conductor 11 is electrically connected to the substrate 1. A suitable voltage may then be applied between the conductors 61 and 11. The electrically insulating layer 4 acts as the dielectric of the capacitor.
An electrically conductive coating 5 is applied to the layer 4 above the channel zone 8, between the zones 2 and 3, and the coating 5 represents the gate electrode of the FET. Both the coatings 5 and 6 are preferably formed of a conductive material which is resistant to temperatures exceeding 1,000° C. Such conductive material may be, for example, polycrystalline doped silicon, which possesses the advantage that it remains stable at temperatures exceeding 1,000° C. Alternatively, the coatings 5 and 6 may be formed of molybdenum, which is also stable at high temperatures.
Applied to the upper surface of the layer 4, and to the upper surface of the coatings 5 and 6, an electrically insulating layer 44 is provided. The layer 44, like the layer 4, is preferably formed of silicon dioxide. A recess is formed in a portion of the layer 44 adjacent a portion of the upper surface of the coating 5, so that after application of the layer 44, the upper surface of the layer 5 remains exposed. A conductor path 7 is applied to the surface of the layer 44, and electrically contacts the coating 5 through the recess in the area 55 (FIG. 2). In this way, there is a direct connection between the gate electrode 5 of the FET and the conductor path 7, which runs above this electrode and also above the coating 6 and the electrode 61.
The conductor 7 is preferably formed of a metallic conductive material, such as aluminum.
In FIG. 2, a plan view of the apparatus of FIG. 1 is illustrated. The conductor 61 is illustrated as running vertically, while the conductor 7 is illustrated as running horizontally. The conductor 61 is exposed at an edge or terminal portion of the substrate 1, where it can be externally connected. The conductor 7 is exposed on top of the assembly, so that its external connection is made without difficulty.
As illustrated in FIG. 2, the zone 3 is formed as a channel which runs in a vertical direction. This channel may be externally connected at the marginal portions of the substrate 1. The electrical connection between the conductor 7 and the coating 5 lies opposite the channel zone 8 of the transistor.
FIG. 3 shows a plan view of an array including a plurality of the storage elements of FIG. 2. The entire array is supported on a single substrate. The reference numerals in FIG. 3 relate to corresponding portions of the apparatus which have been described in connection with FIGS. 1 and 2. It is apparent that the arrangement illustrated in FIG. 3 consists of a plurality of cells, each of which has an individual field effect transistor and a series-connected capacitor. The source electrodes of the individual field effect transistors are connected to one another by means of the common diffusion channels 3, and the drain electrodes are interconnected by means of the conductors 61. Similarly, the gates of the FET's are interconnected by the horizontal conductors 7. In one arrangement, the several different diffusion channels 3 may be connected with individual digit selecting lines, while the conductor 7 may be connected with individual word selecting lines, to permit independent access to any individual storage cell within the assembly by simultaneously externally connecting the electrodes for such cell. In the arrangement of FIG. 3, the contact points between the conductor 7 and the gate electrodes of the FET' s lie at least partially above the channel zones 8 of the FET's, and thus provide a greater packing density of the individual elements within a given area. The portions of the conductors 7 which overlie the channel zones 8 are indicated by shading 55 in FIGS. 2 and 3.
In the arrangement illustrated in FIG. 3, no connections between the conductor 7 and the individual FET's outside the channel zones 8 of the individual FET's are required. The areas required in prior art arrangements for such connections can therefore be used to support additional FET's and capacitors, in order to produce a substantial increase in the packing density of the storage cells on a given surface area of substrate.
It will be appreciated by others skilled in the art that various modifications and additions can be made in the structure illustrated and described above, without departing from the essential features of novelty thereof, which are intended to be defined and secured by the appended claims. | A MOS integrated circuit incorporating a plurality of storage cells is provided, with a field effect transistor and an individual capacitor for each cell. Electrical conductors make contact with the electrodes of the field effect transistors on two planes, with the conductors connected with the gates of the FET's being disposed in a first plane, and the conductors connected with another terminal of the FET's being disposed in a second plane. | 7 |
TECHNICAL FIELD
The invention involves an electroless palladium plating process.
BACKGROUND OF THE INVENTION
There are essentially three methods of producing a layer of palladium on a surface. These methods are the electroplating or electrodeposition method, the vapor deposition method, and the electroless plating method. The electrodeposition method requires elaborate, expensive equipment to ensure deposition at the correct rate and the proper potential. An additional shortcoming of the electrodeposition method is that electric contact must be made to the surface being plated. For highly complex circuit patterns and in particular in integrated circuits where feature density is high, such electric contact is time consuming and difficult to accomplish. In addition, the surface being plated must be electrically conducting and connected to an external source of voltage and current. Vapor deposition also has some inherent disadvantages. In many applications, elaborate high vacuum equipment is required and considerable palladium metal is wasted in the evaporation procedure. There is no convenient way to require the evaporated palladium to adhere only to selected areas on the surface being plated. In other words, pattern delineation with palladium is not easily carried out using the vapor deposition procedure.
Particularly desirable is an electroless plating procedure for palladium in which the palladium plates out on particular surfaces, generally catalytic or sensitized surfaces. Further, it is desirable that such a procedure be carried out using a reasonably stable plating solution. Also, it is desirable that the electroless palladium plating procedure yields plating thicknesses of practical interest particularly where the palladium is used as conducting elements in electrical circuits such as integrated circuits. Often, this means that the electroless plating process should be autocatalytic so that the process continues even after the surface is covered with metallic palladium.
SUMMARY OF THE INVENTION
The invention is a process for electroless plating palladium metal using a unique plating solution. The plating solution contains a source of palladium, optionally an organic ligand, and a narrow class of reducing agents. Suitable reducing agents are formaldehyde, formic acid, hypophosphoric acid and trimethoxyborohydride. The plating solution is made acidic generally by the addition of an acid such as nitric acid or hydrochloric acid. A large variety of organic ligands may be used. These ligands improve the appearance and smoothness of the plated palladium. The organic ligands are generally organic acids such as carboxylic acids, dicarboxylic acids, sulfonic acids, aminosulfonic acids such as 4-aminobenzenesulfonic acids, and sulfonic acid. Additives such as saccharin may be used to improve the properties of the palladium film. The plating process may be carried out at a variety of temperatures from the freezing point of the plating solution to the boiling point of the plating solution. Preferred is the temperature range from 20 to 70 degrees C. with best results obtained near room temperature or slightly higher (20-50 degrees C.) when higher plating rates are desired. A particular advantage of this process is that the palladium will plate out on a variety of catalytic surfaces, including palladium surfaces. For this reason, existing palladium surfaces which are too thin for some applications can be made thicker by this process without masking or making electrical connections to the existing palladium surfaces. In addition to palladium, a large class of elements, alloys and intermetallic compounds are catalytically active including, for example, copper, gold, silver, nickel, and platinum.
Among the alloys of particular interest are permalloy and Kovar which are catalytically active. On some surfaces, an oxide layer is removed to make the surface active. Other materials can be made catalytically active by evaporating or chemically depositing a catalytically active substance on the surface. Rather intricate designs of palladium plating can be made by evaporating a small amount of catalytic metal through a mask and onto a passive surface and then electrolessly plating palladium onto the catalytic metal.
BRIEF DESCRIPTION OF THE DRAWING
The FIGURE shows an electroless plating apparatus useful in the practice of the invention.
DETAILED DESCRIPTION
The invention in broad terms involves the discovery that for electroless plating of palladium, an acid solution of palladium in the presence of certain organic ligands and with a narrow class of reducing agents yields excellent results both in terms of the plating speed and quality and in terms of the stability and shelf-life of the plating solution. The reducing agent should be one or more of the substances selected from the following: formaldehyde, formic acid, hypophosphoric acid and trimethoxyborohydride. Formaldehyde is preferred because of availability and the excellent results obtained. Some reducing agents may be added as salts (sodium or potassium formate, sodium or potassium hypophosphate, etc.) but are converted to the acid form in the acidic plating solution.
An important aspect of the invention is the composition of the electroless plating solution. The plating solution contains a source of palladium, usually added as a palladium salt such as palladium chloride, palladium bromide, palladium nitrate, palladium sulfate, palladium oxide or hydroxide. Concentrations (in terms of palladium metal) may vary over large limits including from about 0.001 to 1.0 molar but generally relatively low concentrations (0.01 to 0.2 molar) are preferred because the solution is more stable and large amounts of palladium are not needlessly kept in the solution.
The electroless plating solution is aqueous and acidic, preferable with pH less than two. More preferably, pH should be less than 1.5 or even 1.0. The solution is made acidic by the addition of an acid agent such as nitric acid, hydrochloric acid, sulfuric acid, etc.
Various additives may be used to improve the performance of the plating process especially as to the quality of the plating. Typical additives are organic ligands selected from a particular class of organic acids. Suitable organic ligands are monocarboxylic acids with up to 10 carbon atoms and dicarboxylic acids with up to 10 carbon atoms. Also useful are sulfonic acids with up to 10 carbon atoms, sulfanilic acid (4-aminobenzenesulfonic acid) and sulfamic acid. The carboxylic acid and dicarboxylic acids may have certain substituents in the carbon chain, namely chlorine, bromine and hydroxyl groups. The sulfonic acid may have in addition to chlorine, bromine and hydroxyl substitution, aromatic substitutions such as benzene (C 6 H 5 --), chlorobenzene, bromobenzene and hydroxybenzene. The limitation on the number of carbon atoms arises to insure sufficient solubility in aqueous solutions to insure effectiveness.
Preferred are certain simple and easily available acids such as oxalic acid, tartaric acid and citric acid. These organic ligands are often added in the form of salts (sodium oxalate, potassium tartarate, etc.) but are converted to the acid in the acidic plating solution.
These organic ligands tend to stabilize the electroless plating solution possibly by complexing with the palladium ion. The presence of the organic ligand in the plating solution greatly improves the quality of the plating with regard to smoothness, brightness, uniformity and adherence. Although the exact mechanism for this behavior is not known, one possibility is that the organic ligand coats the surface to be plated. Other organic ligands may also be useful including organic amines, etc. Concentrations may vary over large limits, including from 0.001 molar to about 1.0 molar. Generally, 0.1 to 0.5 molar yields excellent results.
The reducing agent is crucial to the proper operation of the process. The reducing agent should be strong enough to insure proper reduction of the palladium without being so strong as to induce spontaneous reduction in the absence of the surface to be plated.
It has been found that a select group of reducing agents, namely formaldehyde, formic acid, hypophosphoric acid and trimethoxyborohydride in aqueous medium are suitable as reducing agents for the electroless plating of palladium in acid medium. Preferred is the formaldehyde both from the point of view of availability, low cost, etc., and because of solution stability and the excellent plating results obtained. Concentrations of the reducing agent may vary over large limits, including from about 0.001 to 2.0 molar. Best results are obtained from 0.01 to 1.0 molar. Too low a concentration slows the deposition rate and requires too frequent replenishment of reducing agent; too high a concentration increases the danger of spontaneous deposition. Generally, the reducing agent is replenished so as to keep its concentration range within the limits set forth above. Either bulk replenishment or continuous replenishment is useful in the practice of the invention.
Certain other additives may optionally be added to the electroless plating solution to improve the appearance and properties of the plated palladium. Typical additives are saccharin, cumarin and phenolphthalein. Typical concentrations are 0.001 to 0.1 molar with 0.001 to 0.01 molar preferred. Below 0.001, no effect is likely and above 0.1 molar no additional benefits are found and it might limit the solubility of other components of the bath.
A typical example might serve to illustrate the invention. A solution is made up of 0.1 molar palladium chloride, 0.4 molar formic acid, 1.0 molar nitric acid, 2.0 molar formaldehyde (added as an aqueous solution) and a small amount (about 0.002 molar) of saccharin. The plating is carried out on coupons of brass previously cleaned by first exposing the surface to 20 percent aqueous sulfuric acid, rinsing with deionized water, ultrasonically cleaning in an alkaline cleaner, again cleaning in 20 percent aqueous sulfuric acid and finally rinsing in deionized water. Plating is carried out by exposing the surface of the coupons to the plating solution for a measured amount of time, generally 5 minutes. The plating solution is mildly agitated during plating. The deposits are bright and adherent. Excellent results are also obtained on copper and gold substrates. The plated coupons are sectioned to obtain thickness measurements. The plating rate is about 6 microinches per minute. Plating is also obtained on semiconductor surfaces such as gallium arsenide, indium phosphide and silicon. The gallium arsenide and indium phosphide is cleaned with a one percent bromine in methanol solution. The silicon surface is cleaned using an HF-peroxide solution.
Similar results are obtained with 0.005 molar palladium, 0.2 molar palladium, 0.5 molar HCl and tartaric acid or oxalic acid substituted for formic acid.
The procedure can be used to electrolessly plate palladium on non-catalytic surfaces by activating these surfaces by well-known procedures. For example, an activation solution may be used on the surface covered with catalytic metal by evaporation or other means. Often, (particularly on well-cleaned surfaces), initial deposition might occur by chemical deposition or replacement plating (e.g., where palladium ions in the electroless plating solution reacts with a metal on the surface being plated) and the thin layer of palladium so deposited acts as the catalytic metal for the autocatalytic electroless process described above.
The FIGURE shows an exemplatory plating apparatus 10 useful in the practice of the invention including vessel 11 to contain the plating solution 12, plastic board 13 with strips 14 of catalytic material to be plated electrolessly with palladium. | A process is described for electrolessly plating palladium metal on a variety of surfaces including palladium surfaces. The process involves use of a special electroless plating bath which is sufficiently stable for practical commercial use and yields excellent plating results. The plating bath contains a palladium salt and organic ligand. A narrow class of reducing agents is used including formaldehyde. The bath is made acid generally by the addition of nitric acid or hydrochloric acid. The process yields plating rates of about 6 microinches per minute and plating thicknesses in excess of 1 micrometer. | 2 |
This is a continuation-in-part of application Ser. No. 10/942,078 filed on Sep. 14, 2004, now U.S. Pat. No. 7,581,375, which is incorporated herein in its entirety by this reference
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to machines and methods for harvesting food crops, and more particularly, to improved small-scale machines and related methods for separating larger volumes of vine-borne crops from their vines while effectively removing unwanted dirt, vegetation and debris, minimizing damage to the fruit itself, and promoting better sorting of fruit.
2. Description of the Prior Art
Vine-borne crops have traditionally been harvested and processed by hand. However, such manual harvesting and processing was often tedious, time-consuming and expensive. Various machines, such as the one disclosed in U.S. Pat. No. 6,033,305, have been developed over the years to automate part, or all, of this process. These machines are able to harvest vine-borne crops from the ground at much faster speeds than humans. However, these machines were often inefficient in other aspects of the harvesting process. Early harvesting machines severed entire plants and dropped them upon the ground, with the desired crops remaining affixed to the plants. Then, collection devices would retrieve the mixture of vegetation, dirt and debris for processing. Human sorters would then be required to sort through the mixture to separate the crops from the rest, and extract the former. The human sorters had to quickly process these mixtures to prevent a backlog. As a result, some suitable crops were lost because they were too far entangled within the plants, or simply overlooked by the human sorters.
Various devices have been developed over the years to improve the mechanized harvesting process, and to minimize the need for human sorters. For example, U.S. Pat. Nos. 4,257,218, 4,335,570, and 6,257,978 all disclose harvesting machines utilizing at least one form of agitating device (such as vibrating shaker heads or conveyor belts) to dislodge tomatoes from the vines. Several harvesting machines, such as those disclosed in U.S. Pat. Nos. 6,257,978 and 6,033,305, also utilize forced air pressure systems to further remove dirt and debris.
Unfortunately, larger is not always better. While wider and larger machines are generally capable of harvesting and processing a higher volume of vine-borne crops, many road and/or field situations make it impossible or impractical to use or bring these large machines in to perform the desired harvesting. Such machines are also more difficult to maneuver. Such limited maneuverability may require the machine operator to spend additional time repositioning the machines to process each row of crops, or cause the machines to inadvertently trample one or more rows. In addition, larger machines tend to weigh more, and the added weight not only affects maneuverability (e.g. turning), it also makes the larger, heavier machines unusable in moist or muddy fields where they tend to bog down. It is therefore desirable to provide a smaller scale machine that is capable of harvesting larger volumes of vine-borne crops.
In addition, the design of many existing large and small-scale machines may cause damage to the fruit by imparting numerous drops and/or turns during processing. Many machines require the fruit to drop a distance of several feet over the course of processing through the machine, and to make several turns during the process. Each drop and each turn provides another point where the fruit may be damaged, so it is desirable to minimize the number and/distance that the fruit drops through the machine, and to minimize the number of turns the fruit makes as it travels through the machine.
Effective separating and sorting of harvested fruit is also important. More efficient removal of dirt, vegetation, trash and debris as well as more accurate sorting of fruit is possible when the harvested materials are uniformly dispersed, and not bunched together. An unfortunate side effect of machines in which the fruit makes multiple turns is that the fruit and associated trash and debris tends to bunch together. Rather than the fruits being evenly spaced upon the conveyors (so that they may be easily examined and processed), these corners cause the fruits to become crowded as they are transported onto an intersecting conveyor potentially forming windrows, making them more difficult to inspect and sort. This bunching makes removal of the trash and debris more difficult, and once removed, the bunching of the harvested fruit makes sorting more difficult as well. Furthermore, each turn involves a drop from one conveyor to another, risking additional damage to the fruit, and requiring more maintenance and cleanup from breakage. Transverse turns also tend to increase the overall width and size of the harvester machine. All of these consequences make it even more desirable to minimize the number of turns the fruit makes as it travels through the machine.
Blowers for cleaning trash and debris out of the fruit stream have been used in existing machines. Air from the blower is typically directed between two conveyors into the fruit stream as the fruit makes a ninety degree turn at the rear of the machine. The trash and debris is blown far enough to clear the receiving conveyor and drop off to the ground. It is therefore desirable to provide a machine with a blower unit that does not require the fruit to be subjected to the problems associated with unnecessary turns.
Suction units have also been used in existing harvesting machines for pulling the trash off the fruit stream on each side of the harvester, with the fan positioned in the typical application directly above a pickup point as fruit moves from one conveyor to another. This is not feasible for use on a small scale machine because of vertical space limitations of fitting a sufficiently large enough fan without lengthening the machine further or raising the height and creating shipping problems. The additional single conveyor width compounds the problem. It is therefore desirable to provide an effective suction system that may be used in a small scale machine.
It is therefore desirable to provide a small-scale vine-borne crop harvesting machine capable of processing a large volume of crops that is usable in a wide variety of field situations where larger machines cannot be used. It is further desirable that the harvesting machine effectively process vine-borne crops with minimum potential damage to the fruit. It is further desirable that the machine provide a minimum number of drops and turns so that the fruit is less susceptible to damage, so that trash and debris may be more effectively removed, and so that the fruit itself may be more efficiently sorted.
SUMMARY OF THE INVENTION
The present invention provides compact fruit-vine harvesters and separation systems in which the harvested fruit travels along a vertical plane or path during processing inside the machine, and makes only one ninety-degree turn following such processing in order to exit. The systems include machines and related methods for harvesting vine-borne crops. One embodiment of the machine is relatively compact, having a frame that is dimensioned such that its width is substantially the same as the wheel or track base so that it may travel on narrow roads, and be used in narrow field conditions. The machines provide for vine borne crops to be severed, separated, cleaned and machine-sorted along a single substantially vertical plane or straight (unturning) path inside the machine before making a single turn just prior to exit. Harvested fruit passing through the machines have fewer drops than seen in existing machines (typically two fewer drops). The machines incorporate a blower system, or a suction system, or a combination of blower and suction system for efficient removal of unwanted dirt, vegetation and debris.
In one embodiment, a severing device is provided at the forward end of a machine for severing fruit-laden vines from the ground. A first conveyor is provided that brings the severed fruit-laden vines to an upper position in the machine. It is preferred that this pre-processing (severing and depositing into the machine) be accomplished along the same vertical plane as the remaining processing inside the machine. However, multiple severing devices and/or multiple conveyors may be used to remove and deposit the vines into the machine that may not necessarily be oriented along the same vertical plane. In several embodiments, the severed fruit-laden vines cross an adjustable gap and are delivered onto a second conveyor, the gap allowing loose dirt and debris to fall through the machine to a dirt cross conveyor. In several embodiments, the material on this conveyor is passed through a vision system which ejects the red fruit back into the machine as the dirt and debris pass through to the ground. The fruit-laden vines are introduced into a rotating shaker having tines that engage and loosen the vines, causing the fruit to be dislodged as it shakes. The dislodged fruit drops onto a second conveyor below the shaker, and the vines are deposited onto a third conveyor. While traveling along the third conveyor, which is provided with large slots or as a wider pitch belted chain so that fruit can pass through, additional agitation may be imparted to the vines to dislodge any remaining fruit which falls through and is returned to the second conveyor. All of the conveyors are set up relatively close to each other so as to minimize the dropping distance of the fruit. These conveyors are all lined up substantially along the same vertical plane, so that the fruit and related materials are not turned and remain uniformly dispersed across the width of the conveyors.
Some dirt, debris, and vegetation may be deposited on the second conveyor along with the dislodged fruit. To remove this remaining trash, in several embodiments the second conveyor delivers the fruit and trash across an adjustable gap in which a strong upward air flow is provided through a nozzle attached to a blower below. The nozzle extends along the width of the second conveyor so that all fruit and trash is affected thereby. The airflow may be adjusted so that it is strong enough to blow away substantially all loose dirt, debris and vegetation without blowing away the fruit itself. The airflow also tends to remove trash and vegetation that may have become adhered to the second conveyor because of moisture or the like.
In some embodiments, an intake opening for a variable speed suction unit may be provided above the gap and blower nozzle to receive and remove all of the trash that is blown free by the lower nozzle. In other embodiments, one or more suction units are provided without any blower, preferably located along one or both sides of the fruit path, with special ducting to focus the suction over the fruit traveling through the machine along the vertical plane.
In some embodiments of the dual system using both blower and suction, one or more flaps are pivotally provided in the ducting for the blower system. Such flaps are activated when it is sensed that airflow has been affected by a large piece of vine engaged (clogged) in the suction system. When this condition is sensed, as, for example, a change in static pressure, a flap on the blower nozzle is moved so as to redirect the air flow forward in the machine and partially deadhead the blower, cutting off the airflow until the clog is cleared. This prevents trash that should be sucked up by the clogged suction unit from being blown all over the cleaned fruit on the conveyor. Once the clog is cleared, the normal condition is again sensed, and the flaps are returned to their original position(s) for normal operation.
In several embodiments, one or more continuously rotating rollers may be provided adjacent to the upper intake opening to dislodge any large pieces of vegetation or trash to prevent the upper opening from becoming clogged. Each roller itself is preferably smooth so that it does not become entangled with the vegetation or trash, but it may be provided with teeth, lagging, textured covering or tines to engage such materials if so desired. Each roller may rotate in either direction, so long as it tends to keep the vegetation and trash from clogging the intake opening of the upper suction unit.
The cleaned fruit that passes through the blower/suction gap is then deposited onto a fourth conveyor that is also in line with the three previous conveyors. The fourth conveyor takes the fruit to an automatic sorting unit which kicks out unwanted fruit according to its programmed instructions. Since the fruit has not traveled through any turns up to this point, it remains evenly separated on the fourth conveyor thereby improving the sorting process. Then, finally, the fruit makes its one and only turn where it is deposited onto a transversally oriented conveyor. Here, hand sorting may be performed, followed by deposit of the fruit onto a final conveyor which takes it up and out of the machine, usually for deposit into a waiting hopper alongside the machine. In an alternative embodiment, the transversally oriented conveyor and the final conveyor are one and the same, making the fruit available for sorting and then elevating it out of the machine to the hopper waiting alongside.
It is therefore a primary object of the present invention to provide a machine for harvesting vine-borne crops in which the harvested fruit travels along a substantially straight path within the machine as the fruit is separated from the vines, cleaned and sorted, prior to making a single turn followed by exit.
It is also an important object of the invention to provide a machine for harvesting vine-borne crops in which the harvested fruit travels a minimal distance from the uppermost to the lowermost point during processing, reducing the overall distance the fruit drops through the machine in order to reduce the potential for damage to the fruit.
It is also an important object of the invention to provide a machine for harvesting vine-borne crops in which the harvested fruit is uniformly dispersed as it is conveyed through the machine to facilitate better removal of unwanted trash and debris, and to facilitate better sorting of fruit.
It is also an important object of the invention to provide a machine for harvesting vine-borne crops in which unwanted dirt, vegetation and debris is removed through the action of an adjustable blower device provided along the path of travel through the machine.
It is also an important object of the invention to provide a machine for harvesting vine-borne crops in which unwanted dirt, vegetation and debris is removed through the action of adjustable suction device(s) provided along the path of travel through the machine.
It is also an important object of the invention to provide a machine for harvesting vine-borne crops in which unwanted dirt, vegetation and debris is removed through the dual action of an adjustable lower blower device and an adjustable upper suction device that are provided adjacent to each other along the path of travel through the machine.
It is also an important object of the invention to provide a small-scale machine for harvesting large volumes of vine-borne crops that may be deployed in vineyards and fields where larger machines cannot be efficiently used.
It is also an important object of the invention to provide improved methods for harvesting and processing vine-borne crops.
Additional objects of the invention will be apparent from the detailed descriptions and the claims herein.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of an embodiment of the present invention.
FIG. 2 is a side view of an embodiment of the present invention along line 2 - 2 of FIG. 1 .
FIG. 3 is a rear view of an embodiment of the present invention along line 3 - 3 of FIG. 1 .
FIG. 4 is a cut away side view along line 4 - 4 of FIG. 1 illustrating major operative elements of flow paths through the invention.
FIG. 5 is a detailed cut away side view along line 5 - 5 of FIG. 1 of an exemplary air blower and air suction device of an embodiment of the present invention.
FIG. 6 is a side view along line 6 - 6 of FIG. 1 of an exemplary mechanical fruit sorter of an embodiment of the present invention.
FIG. 7 is a top view of a suction device of an embodiment of the present invention along line 7 - 7 of FIG. 2 .
FIG. 8 is a side view along line 8 - 8 of FIG. 16 of another embodiment of the present invention illustrating a blower for cleaning harvested crop.
FIG. 9 is a top view of the embodiment of FIG. 16 showing the cleaning elements.
FIG. 10 is a side view along line 10 - 10 of FIG. 17 of another embodiment of the present invention illustrating overhead suction for cleaning harvested crop.
FIG. 11 is an end view along line 11 - 11 of the embodiment of FIG. 16 .
FIG. 12 is a rear view along line 12 - 12 of FIG. 18 of another embodiment of the present invention illustrating dual suction fans for use in cleaning harvested crop.
FIG. 13 is a top view of the embodiment of FIG. 18 showing cleaning elements
FIG. 14 is a side view of an alternative embodiment of the present invention showing the blower and suction fan system operating under normal conditions.
FIG. 15 is a side view of the embodiment of FIG. 14 showing the blower and suction fan under a plugged/clogged state with the blower flap directing air forward in the machine.
FIG. 16 is a top view of an alternate embodiment of the present invention having a blower only.
FIG. 17 is a top view of an alternate embodiment of the present invention having a suction fan only.
FIG. 18 is a top view of an alternate embodiment of the present invention having dual suction fans.
DETAILED DESCRIPTION
Referring to the drawings wherein like reference numerals designate like or corresponding parts throughout the several views, and referring particularly to FIGS. 1 and 2 , it is seen that the illustrated exemplary embodiment of the invention is an apparatus and method for harvesting above-ground food plants grown in rows upon elongated planting ridges. The exterior components of the illustrated apparatus generally comprise a self-propelled vehicle body 10 having a driving compartment 11 , an adjustable arm 12 with a pickup device 14 and conveyor 15 , separator 20 , optional sorting platform 16 , and a discharging conveyor 17 .
As indicated in FIG. 2 , an adjustable arm 12 may be affixed to the front end of the vehicle body 10 . The adjustable arm 12 may be any number of commercially available devices that allow the operator to adjust the position of the arm 12 relative to the ground, said position depending upon the characteristics of the particular crop harvested or its environment. A gage wheel 13 for height adjustment may be mounted at the front end of the adjustable arm 12 . The pickup device 14 may be any commercially available device capable of severing tomato vines V at or near ground level, such as a cutting disc or plurality of opposing blades, and a lift for placing the severed vines onto conveyor 15 . The pickup conveyor 15 may be an endless longitudinal conveyor belt traveling in a rearward direction into the separator 20 . Sorting platform 16 may be affixed to the rear end of the vehicle body 10 . Platform 16 allows one or more humans to examine and hand sort the tomatoes T on conveyor 26 before they are passed along to a discharging conveyor such as 17 . Conveyor 17 is depicted in the rear view of FIG. 3 in its retracted position, with phantom lines showing its extended position over a receiving hopper 70 in an adjacent row.
FIG. 4 depicts the internal operation of one embodiment of the separator 20 of the present invention viewed from the right side. In this embodiment, an endless motor-driven longitudinal receiving conveyor 19 is adapted to receive the tomato vines V from the exterior pickup conveyor 15 and travel toward the rear end of the vehicle body 10 . An adjustable gap 18 is provided between the pickup conveyor 15 and receiving conveyor 19 , said gap 18 allowing loose tomatoes T, dirt clods and other debris to drop from the vines V while said vines travel between the two conveyors 15 and 19 . It is to be appreciated that the width of gap 18 may be varied to account for different sizes of vines V, tomatoes T, dirt clods and debris. For example, gap 18 may be set at a sufficiently small size that only the smaller dirt clods and debris fall through, or at a sufficiently large size that larger objects including small loose tomatoes T may also fall through.
In some embodiments, an endless transversely oriented motor-driven debris conveyor 21 , having one end underneath gap 18 and the opposite end extending outside the vehicle body 10 , may be positioned to receive the loose tomatoes T, dirt clods and debris falling through gap 18 . A commercially available sorting mechanism 27 may be mounted in close proximity to the debris conveyor 21 to recognize loose tomatoes T thereon, and place them onto the endless motor-driven collection conveyor 29 mounted under conveyor 21 . The remaining dirt clods and debris fall off conveyor 21 and outside the vehicle body 10 . Tomatoes T are collected on 29 and conveyed back up on to the machine and deposited onto an endless motor-driven longitudinal first processing conveyor 22 . Alternatively, if gap 18 is set at a sufficient size to allow only dirt clods and debris to fall through, the debris conveyor 21 may transport all objects falling through the gap 18 to the outside of the vehicle body 10 .
A shaker brush 30 is positioned for receiving tomatoes and vines from processing conveyor 19 . Said shaker brush 30 may be any commercially available brush comprising a plurality of tines 31 and an agitating mechanism (not depicted) for concurrently rotating and vibrating the shaker brush 30 , such as an eccentric weight assembly or vibrating motor. It is rotatable along a central axis in a downward direction, causing the vines V to be pulled underneath the shaker brush 30 toward the rear end of the vehicle body 10 . The vibratory force of the shaker brush 30 is sufficient to dislodge tomatoes T from their vines V, along with most remaining dirt clods and debris, without excessively damaging the tomatoes T. The dislodged tomatoes T, dirt clods and debris are dropped onto the first processing conveyor 22 , while the vines V are deposited upon the recovery conveyor 23 .
Processing conveyors 22 and 29 (described below) are made up of segments which provide a plurality of openings or slots that are of sufficient size to support tomatoes T, but allow small pieces of dirt, vegetation and debris to fall through. Larger pieces are removed by blower 40 and suction device 60 described below.
The illustrated exemplary recovery conveyor 23 is an endless motor-driven longitudinal conveyor traveling toward the rear end of vehicle body 10 . Conveyor 23 is made up of segments which provide a plurality of openings or slots that are of sufficient size to allow tomatoes to fall through. An agitating mechanism (not depicted) may be provided in communication with the recovery conveyor 23 . Said agitating mechanism may be any commercially available device for agitating the tomatoes and vines on the recovery conveyor 23 . The agitator should be capable of providing loosening vibratory motions to further separate the tomatoes T that remain entangled but not connected with the vines V at this stage. A recovery shelf track 24 is positioned underneath the return segment of the recovery conveyor 23 to capture the tomatoes T falling through the slots of the recovery conveyor 23 , and, in conjunction with the return movement of the recovery conveyor 23 , transport the tomatoes T to the first processing conveyor 22 .
The illustrated exemplary second processing conveyor 25 is an endless motor-driven longitudinal conveyor belt traveling toward the rear end of vehicle body 10 . Conveyor 25 is positioned near the rear end of first processing conveyor 22 . There is an adjustable gap 28 between the first processing conveyor 22 and the second processing conveyor 25 . In some embodiments, an air blower 40 is mounted below the front end of the second processing conveyor 25 , with the nozzle 43 directed toward the gap 28 between the two conveyors, so that the forced air pressure emitted from the nozzle 43 contacts the tomatoes T, vegetation, dirt and debris falling from the first processing conveyor 22 onto the second processing conveyor 25 . Such forced air pressure may be varied so that it is of sufficient strength to separate vegetation, dirt and debris from the tomatoes T, and force said materials upward and towards the rear without blowing the tomatoes themselves away. In some embodiments, nozzle 43 may be provided with a narrow slit opening 42 to focus the flow of air as shown in FIG. 9 . Optional roller(s) 45 may be used to help with the separation of blowing materials by rotating counterclockwise and direct the said materials towards the collection conveyor 72 . The vegetation, dirt, and debris may be collected on a transverse conveyor 72 mounted behind roller(s) 45 and directly above conveyor 25 . The collected dirt and debris are directed off the side of the machine falling to the ground.
In some embodiments, an air suction device 60 , such as a fan or vacuum, is positioned above the gap 28 , as shown in FIG. 10 . The size and shape of the vacuum opening 63 may be varied, as discussed below, to assure that equal air suction (vacuum) is provided across the entire path (width) of conveyor 22 and gap 28 . The vacuum imparted by this suction device 60 may be varied so that it is of sufficient strength to capture the dirt, vegetation and debris.
In one embodiment, the suction fan 60 is positioned vertically on the side, with ducting to connect the pickup nozzle area to the inlet of the fan. (See FIG. 7 .) The additional width of the conveyor is an additional challenge for the fan. To overcome this, a larger unit drawing even more power may be used. In alternative embodiments, dual fans 60 may be provided, one on each side of the fruit path, with ducting allowing the entire fruit path to be subject to suction, as shown in FIGS. 12 , 13 and 18 .
FIG. 5 provides a detailed side view of an embodiment using both the air blower 40 and air suction device 60 of the present invention. As shown therein, the nozzle 43 of the air blower 40 is positioned in close proximity to and across the width of gap 28 between the first processing conveyor 22 and second processing conveyer 25 , so that the forced air pressure emitted through nozzle 43 contacts the tomatoes T, dirt clods and debris falling from the first conveyor 22 to the second 25 . The suction device 60 is positioned above the gap 28 with its opening 63 directly across from the nozzle 43 , so that the forced air pressure emitted from the nozzle 43 (and the dirt, vegetation and debris carried by such pressure) is directly received by the opening 63 of the suction device 60 . The volume of air provided by the blower and/or suction should generally be adjusted as high as possible without being so strong as to remove the tomatoes themselves.
Blower 40 also provides the additional function of dislodging vegetation or debris that may have become adhered to conveyor 22 through moisture or the like, thereby improving the efficiency and operational functionality of conveyor 22 . It is to be appreciated that in other embodiments, blower 40 may be provided without suction 60 (see FIGS. 8 , 9 , 11 and 16 ), and in other embodiments suction 60 may be provided without blower 40 (see FIGS. 10 and 17 ).
In some embodiments, at least one roller 45 is provided. Roller(s) 45 may be provided adjacent to and below the opening 63 of suction device 60 ( FIG. 5 ), or above the nozzle 43 of the blower device ( FIG. 9 ), and extending across the width of opening 63 or nozzle 43 . Roller(s) 45 may have a smooth surface, or may be provided with teeth, lagging or tines of appropriate length to engage the vegetation and other dislodged debris. In the suction embodiments of the present invention, roller(s) 45 rotate while the suction device 60 is operating so as to make contact with and dislodge any excessive vegetation or other debris in order to prevent opening 63 from being clogged. As shown in FIG. 5 , roller(s) 45 may be rotated in a clockwise direction so as to continuously be causing vegetation and debris to be pushed out and away from opening 63 . However, this may cause such vegetation and debris to be deposited with the relatively clean tomatoes T on conveyor 25 . Thus, in many circumstances, it may be more beneficial for one or more of rollers 45 to rotate counter-clockwise so as to force the vegetation and debris into opening 63 so that it may be carried away. Among other things, the size and moisture content of the vegetation and debris may dictate whether roller(s) 45 operate in a clockwise or counter-clockwise direction, or some rollers in one direction and others in the opposite direction.
FIGS. 8 and 9 illustrate an embodiment of a blower used on the small scale machine. On the side view of FIG. 8 , a blower outlet 43 is positioned to direct air upward through the gap 28 between two conveyors 22 and 25 . The air goes through the fruit stream, lifting the lighter trash upward into the air chamber and over optional roller(s) 45 . In this embodiment, roller(s) 45 help deliver debris onto a cross conveyor 72 where it may be transferred into an optional removal chute 75 . On the backside of the roller 45 , the air is allowed to vent out one side in a larger cavity with a conveyor underneath. Part of the trash in the air settles out and is conveyed to the side of the machine with the conveyor 72 . The lighter trash will likely stay airborne and vent out with the air to the side. In some embodiments, the air may be vented off both sides, with the conveyor split to run both directions. In another embodiment, air may also be allowed to vent towards the rear of the machine through a screen. In this embodiment, when the system stops at the end of the field, the air-stream would stop, and the loose trash collected on this screen would fall down to the conveyor.
In some embodiments, accommodation for trash collection and directing material to the ground with a flexible chute 75 (see FIG. 11 ) made with flaps may be needed to prevent light trash from collecting in the wrong places and causing engine or hydraulic overheating. The trash conveyor 72 is preferably a flat belt, not a belted chain. On FIG. 8 , the sides of the air chamber are enclosed to direct the trash over roller 45 to the collection conveyor. The underside of the recovery shelf track 24 serves as the top of the air chamber.
A side view of a suction device 60 is shown in FIG. 5 , and a top view is shown in FIG. 7 . In this illustrated embodiment, suction device 60 includes a variable speed fan or blower unit 61 attached to a channel 62 that is attached, in turn, to a duct 64 leading to opening 63 . An exhaust duct 65 may also be provided. Because of the change in direction of airflow through channel 62 and duct 64 , the size and shape of opening 63 may be varied so as to provide a uniform level of suction across the entire path of conveyor 25 and gap 28 . By way of example and without limitation, opening 63 may not be provided in a rectangular form, but the left side of opening 63 may be narrower than the right side so as to assure level airflow across its length.
In an alternative to the embodiments using both suction 60 and blower 40 , one or more flaps 76 may be provided on the blower outlet nozzle 43 which may be opened or closed to respond to clogging of the suction system by a large clump of vine mass. See FIGS. 14 and 15 . Such a clog causes the suction 60 to lose some of its airflow, and when used with blower 40 , may result in undesirable redirecting of blower air flow blowing trash where it is not wanted. The flap 76 is attached to one or more electronically controlled solenoids or other switches 77 , and a sensor 78 such as a static air pressure sensor is provided adjacent to the suction unit. If the sensor 78 detects a change in air pressure brought about by a clog caused by a large vine mass ( FIG. 15 ), the switches 77 are activated closing the flap 76 so as to redirect the air from the suction system forward in the machine into conveyor 22 , until the clog has cleared. See upward arrow of FIG. 15 . The clearing of the clog is sensed by the pressure returning to normal, at which point the switches 77 are deactivated returning the flaps to their normal operating positions, as shown in FIG. 14 .
FIGS. 12 , 13 and 18 illustrate an alternative embodiment using a dual suction fan arrangement. The top view of FIG. 13 shows ducting to both sides of the machine with no dividing partition inside the ductwork. Air is allowed to flow freely through with no catch point for trash to hook on. A very large volume of air can be moved with this embodiment without needing the additional space required for a single overly sized unit. The horsepower required to drive this embodiment is significant, but all the trash collected may be controlled.
It is to be appreciated that all of conveyors 15 , 19 , 22 , 23 and 25 are provided along the same vertical plane, and are operatively positioned, as described herein, above and/or below each other in this plane. In this way, the tomatoes T removed from the vines travel along a straight path, moving from, the front toward the rear of the machine, being directed by the conveyors and by gravity. This configuration avoids any left or right turns in the path that the tomatoes T travel through the machine, resulting in better distribution of the tomatoes across conveyor 25 when they reach the sorting stage. Left and right turns in the paths of other machine cause the tomatoes to roll together into windrows that are more difficult to separate and sort.
In some embodiments, an endless motor-driven transversely oriented output conveyor 26 may be positioned near the rear end of the second processing conveyor 25 . A gap is provided between the second processing conveyor 25 and the output conveyor 26 . An optical/mechanical fruit sorter 50 is mounted in close proximity to this gap. The optical/mechanical fruit sorter 50 may be any commercially device capable of selecting or rejecting tomatoes T based upon certain predetermined criteria, such as color. It should also comprise a means of sorting tomatoes T based upon their satisfaction of the predetermined criteria, such as a mechanical arm or pivoting gates. It is to be understood that the mechanical fruit sorter 50 may be replaced by, or supplemented with, human sorters who can manually examine the tomatoes on conveyor 26 as they stand on platform 16 .
Regardless of the particular examination method utilized, tomatoes T satisfying the predetermined criteria are transported to output conveyor 26 , while rejected tomatoes are removed therefrom, either by the mechanical sorter 50 or human sorters. The output conveyor 26 is in communication with the discharging conveyor 17 , which transports the satisfactory tomatoes from the present invention onto any number of commercially available hoppers, such as a trailer or truck bed 70 .
FIG. 6 depicts an embodiment utilizing a mechanical fruit sorter 50 located along the same vertical plane. It is seen that the mechanical fruit sorter 50 comprises a sensor 51 and pivoting gate 52 . The sensor 51 may be any commercially available device capable of determining whether the tomato T satisfies the predetermined criteria inputted by the operator. Tomatoes T satisfying such criteria are permitted to fall toward output conveyor 26 . As to tomatoes T 1 failing such criteria, the fruit sorter 50 causes the gate 52 to pivot outward, causing the failing tomatoes T 1 to miss the output conveyor 26 and fall outside the vehicle body 10 .
The use of a particular embodiment of the present invention will now be described without limiting the claims herein. In this exemplary embodiment, the operator inputs a series of predetermined criteria into the mechanical fruit sorter 50 , which defines the parameters for the ‘acceptable’ tomatoes harvested. The size of gap 18 is selected and set. The initial airflow for blower 40 and/or suction 60 is also selected (depending upon whether one or both is provided), although these may be changed during processing to provide appropriate removal of debris. The exemplary invention is then positioned before a row of tomato vines V. The adjustable arm 12 is placed in such a manner that the cutting device 14 will sever the tomato vines V at or near ground level. As the present invention proceeds along the row of tomato vines V, cutting device 14 severs the tomato vines V. The pickup mechanism receives the severed tomato vines V (along with loose tomatoes T, dirt clods and debris), and places them onto the pickup conveyor 15 . The pickup conveyor 15 then transports the vines V rearward into separator 20 .
The tomato vines V are transported over the gap 18 between the pickup conveyor 15 and receiving conveyor 19 . As they cross the gap, loose tomatoes T, dirt clods and debris smaller than the width of the gap fall through, and onto the debris conveyor 21 . The debris conveyor 21 passes the mixture through a sorting mechanism. Tomatoes T within the mixture are diverted to the collection conveyor 29 , then dropped onto the first processing conveyor 22 , while the dirt clods and debris passing through the sorting mechanism are discarded outside the vehicle body 10 .
The tomato vines V upon the receiving conveyor 19 travel along a vertical plane and contact the shaker brush 30 . As the downward rotation of the shaker brush 30 pulls the tomato vines V underneath the brush, the vibration of the brush tines 31 dislodges the tomatoes T from the vines V, along with the remaining dirt clods and debris. The dislodged tomatoes T, dirt clods and debris fall onto the first processing conveyor 22 , while the vines V (along with any tomatoes T still lodged therein) are deposited by the shaker brush 30 upon the recovery conveyor 23 .
As the recovery conveyor 23 transports the vines V along the vertical plane toward the rear of the vehicle body 10 , it is vibrated by an agitating mechanism. The vibrating motion of said mechanism is sufficient to dislodge the remaining tomatoes T from the vines V. These tomatoes T fall through the slots of the recovery conveyor 23 onto the recovery shelf track 24 . The vines continue rearward until they are ejected from the rear end of the vehicle body 10 . The return direction of the recovery conveyor 23 receives the tomatoes T and deposits them upon the first processing conveyor 22 , along with the tomatoes T dislodged by the shaker brush 30 .
The first processing conveyor 22 continues to transport the tomatoes T (and remaining dirt clods and debris) toward the rear end of the vehicle body 10 along the vertical plane. When the mixture reaches the rear end of the first processing conveyor 22 , it falls to the second processing conveyor 25 along the plane. During the fall, the mixture is struck by air pressure from the air blower 40 (if provided) mounted underneath the second processing conveyor 25 . The air should be of sufficient volume to cause the tomatoes to “dance,” that is, to be moved slightly so that the debris and vegetation around them is removed, while the tomatoes themselves are not. Such air pressure causes the dirt and debris to separate from the tomatoes T and fly upward, where they are captured by suction pressure from the air suction device 60 (if provided). The suction device 60 ejects the dirt clods and debris from the rear end of the vehicle body 10 , while the tomatoes T continue along the second processing conveyor 25 .
As the tomatoes T reach the rear end of the second processing conveyor 25 , they are analyzed by a mechanical fruit sorter 50 along the vertical plane. Tomatoes T satisfying the particular criteria previously inputted by the operator are transported onto output conveyor 26 , while unacceptable tomatoes are discarded out the bottom of the vehicle body 10 . The output conveyor 26 transports the acceptable tomatoes T past manual sorters standing on platform 16 , and then to the discharging conveyor 17 , where the tomatoes T are placed into transport hoppers 70 .
It is to be understood that variations and modifications of the present invention may be made without departing from the scope thereof, including different combinations of the various elements identified herein regardless of whether such combinations have been specifically described or illustrated. It is also to be understood that the present invention is not to be limited by the specific embodiments disclosed herein, but only in accordance with the appended claims when read in light of the foregoing specification. | The present invention is a compact fruit-vine harvester and separation system in which the harvested fruit travels along a vertical plane inside the harvester during processing, followed by a single turn for output. The system includes a machine and related methods for harvesting vine-borne crops. The machine provides for vine borne crops to be severed, separated, cleaned and machine-sorted along a straight path before making a single turn prior to exit. The machine incorporates a blower and/or suction system for efficient removal of unwanted dirt, vegetation and debris, and an optional roller to prevent clogging of the suction system. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority under 35 U.S.C. 119 of European Patent Application No. 07 004 300.5, filed on Mar. 2, 2007, the disclosure of which is expressly incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
The present invention relates to a method for purifying exhaust gases from a waste incineration plant by utilizing a sorption method in a circulating fluidized bed as well as an exhaust gas purification system.
In the case of waste incineration, the exhaust gases being generated during that process are usually purified by separating the pollutants contained therein, such as HCl, HF, SO 2 , nitrogen oxides and dioxin as well as dusts, in an exhaust gas purification system.
A possible method for separating pollutants such as HCl, HF, SO 2 and dioxins from the exhaust gases is the dry sorption of the pollutants by utilizing a sorbent.
For this, a sorbent is usually introduced into a fluidized bed reactor, where it is put in contact with the exhaust gas in a circulating fluidized bed. The pollutants thereby sorb to the sorbent. Downstream from the fluidized bed reactor is a solids separator. Solid matter carried along in the exhaust gas and consequently also sorbent loaded with pollutant is separated therein. The separated solid matter is either discharged or returned to the fluidized bed reactor.
A corresponding method is described in the document EP-A-1 537 905. There, a first addition of the additive serving as sorbent takes place to the fluidized bed or following the fluidized bed ahead of the separation and a second addition ahead of the fluidized bed to an exhaust gas duct leading to the fluidized bed.
A number of methods have been suggested for the regulation of the amount of sorbent to be supplied as described below.
JP-A-2000107562 describes a method for the regulation of the amount of absorbing powder to be added by determination of the backwash cycles of a bag filter.
EP-A-0 173 403 describes a method for the regulation of the amount of sorbent to be introduced into an exhaust gas stream, wherein the HCl value is used as reference variable, from which the setpoint value is calculated in conjunction with the measured amount of exhaust gas and a temperature dependent stoichiometry value. In this method, the also determined SO 2 content can be included as additional correction. The document does not clearly indicate if the HCl concentration and the SO 2 concentration is measured in the raw gas or in the pure gas.
A control method in which only the HCl concentration in the pure gas is measured (“feedback” control) has the disadvantage that a required sorbent supply does not take place until an increased pollutant content in the emitted clean gas has already been detected. In order to meet this disadvantage, methods were suggested, in which in addition to the above described measurement in the pure gas, also the HCl and SO 2 concentrations in the raw gas are measured, by way of which the theoretically required amount of sorbent can be determined (combined “feedforward/feedback” control).
However, it has been shown that the effectively required amount of sorbent can only be poorly determined by way of the measured concentrations of HCl and SO 2 . This relates to the fact that the circulating solid matter, which together with the actual sorbent comprises further solid components such as fly ash or fuel particles, has a not negligible residual sorption capacity. It is, for example, possible that in the case of a relatively low content of pollutants prior to the sorption, these are not completely separated despite a large amount of fresh sorbent being supplied, since the residual sorption capacity of the circulating solid matter is low and the amount of sorbent required for the treatment of pollutant peaks cannot be supplied to the system quickly enough. On the other hand, it is possible that in the case of a high residual sorption capacity of the circulating solid matter, the supply of fresh sorbent is not even required at all when the pollutant content prior to the sorption is relatively high. As a result of the composition, which varies greatly depending on the composition of the combusted waste, of the exhaust gas and of the entrained solids, the residual sorption capacity can not be determined numerically. If hydrated lime is used as sorbent, then the sorption capacity is additionally influenced by carbonation reactions, which makes a numerical determination of the residual sorption capacity completely impossible.
A further disadvantage of the existing methods for the purification of exhaust gases from waste combustion is found in their lack of operational reliability. The reason for this is that the chloride content of the circulating solid matter strongly fluctuates and, for a specific content in the solid matter, leads to sticking and caking, which, in the extreme case, can completely clog the exhaust gas purification system.
SUMMARY OF THE INVENTION
According to one aspect of the present invention, there is provided a method of the initially mentioned type, wherein the sorbent is optimally utilized and which, at the same time, ensures a high operational reliability.
The method according to an aspect of the invention is characterized in that the mass flow of the supplied fresh sorbent is regulated as a function of the concentration of fresh sorbent and/or at least one sorbed pollutant in the recirculated solid matter.
The residual sorption capacity of the recirculated solid matter is thus taken into account during the regulation of the supply of fresh sorbent. This allows for a significantly more accurate determination of the effectively required mass flow of fresh sorbent than has been the case in the methods known to date. The sorbent is thus optimally utilized, which enables the consumption thereof to be kept to a minimum.
In addition, according to a method of the present invention, the supply of fresh sorbent can be regulated in such a way that the proportion of chlorides during the purification of the exhaust gases is permanently maintained below the critical threshold value for the sticking of the solid particles. This contributes significantly to the operational reliability of the method.
The method of the present invention comprises not only dry sorption methods, but also semi-dry sorption methods.
In this method, the sorbent is available in the form of a circulating fluidized bed, which is generated as a result of the solid particles contained in the exhaust gas, together with the supplied sorbent, being brought into a fluidized state by the upwardly directed exhaust gas stream.
Hydrated lime (Ca(OH) 2 ) is preferably used as sorbent for the method of the present invention. This usually has a purity grade of at least 92% and a specific surface of at least 15 m 2 /g. However, a plurality of further sorbents, such as sodium bicarbonate (NaHCO 3 ), Spongiacal® (Rheinkalk) or Sorbalit® (Märker Umwelttechnik GmbH), is also conceivable. According to the invention, a single sorbent or a mixture of different sorbents can be used.
The pollutants contained in the exhaust gas are separated by way of chemical reaction with the sorbent in the circulating fluidized bed.
If hydrated lime is used as sorbent, the pollutants SO 2 , HCl and HF react in accordance with the following reaction equations to the corresponding salts:
Ca(OH) 2 +H 2 O+SO 2 →CaSO 3 (Calcium sulfite)+2H 2 O
Ca(OH) 2 +2HCl→CaCl 2 (Calcium chloride)+2H 2 O
Ca(OH) 2 +2HF→CaF 2 (Calcium fluoride)+2H 2 O
In these reactions, the temperature for the pollutant separation is preferably approx. 145° C.
Activated carbon (open-hearth furnace coke) is usually also present in the circulating fluidized bed, onto which pollutants are additionally adsorbed and separated from the exhaust gas.
Apart from the sorbent and the activated carbon, as well as the pollutants sorbed to sorbent and activated carbon, the recirculated solid matter generally also comprises fuel particles and fly ash from the firing portion of the waste incineration plant. According to the invention, the mass flow of the supplied fresh sorbent is regulated as a function of the concentration of fresh sorbent and/or at least one sorbed pollutant in the recirculated solid matter.
According to one preferred embodiment of the method according to the invention, the concentration of the respective component(s) in the recirculated solid matter is determined in a substantially continuous manner. According to the invention, the concentration of fresh (unloaded) sorbent, in particular hydrated lime, and/or of sorbed pollutant, in particular chloride, sulfite and/or fluoride, is determined in this way. The supply of the fresh sorbent is adjusted on the basis of the determined concentration of the respective component(s).
The quickest possible reaction to system changes is ensured by the substantially continuous determination of the concentration of the fresh sorbent and/or of the sorbed pollutant in the recirculated solid matter.
In a particularly preferred embodiment, the determination is carried out by utilizing a Fourier Transform near-infrared spectrometer (FT-NIR spectrometer). This enables a continuous quantitative analysis of the recirculated solid matter. The analysis can be carried out in-situ by utilizing a probe disposed in the exhaust gas purification system.
Alternatively to the analysis in-situ, the determination of the concentration of the respective component(s) can be carried out using a sample of solid matter withdrawn from the circulation by utilizing a small cyclone. In this case, the determination takes place batch-wise. If the sample withdrawal takes place in short time intervals, it is possible to carry out a quasi-continuous determination with this embodiment.
A conventional cyclone, such as is known to a person skilled in the art, for example from Lueger, Lexikon der Technik, Stuttgart 1970, vol. 16, p 601 et seq., can be used as cyclone. Preferably, the solids sample is collected in a collection container capable of being automatically emptied. Subsequent to the determination according to the invention, the solids sample is automatically returned to the circulation.
In a further preferred embodiment, in addition to the mass flow of the supplied fresh sorbent, also the mass flow of the solid matter discharged from the circulation is regulated as a function of the concentration of the fresh sorbent and/or of the at least one sorbed pollutant in the recirculated solid matter. In this way, it can be avoided that solid matter having depleted sorption capacity continues to be circulated. In general, the discharging of the solid matter from the circulation is carried out using a discharging device provided for this purpose.
It is furthermore preferable that the mass flow of the supplied fresh sorbent and optionally the mass flow of the solid matter discharged from the circulation is also regulated as a function of the concentration of HCl and/or SO 2 in the raw gas and in the pure gas. The embodiment has the advantage that information on the pollutant content in the raw gas and in the pure gas is obtained directly in this way. This additional information enables furthermore a fine adjustment of the inventive regulation of the mass flow of the supplied fresh sorbent and optionally of the mass flow of the solid matter discharged from the circulation.
In addition there can be further regulating circuits:
In a first further regulating circuit, the pressure loss through the fluidized bed in the reactor is monitored and the mass flow of solid matter recirculated into the fluidized bed reactor continuously regulated in order to maintain a constant inventory of bed material in the fluidized bed reactor.
In a second further regulating circuit, the exhaust gas temperature in the fluidized bed reactor is regulated by utilizing water injection.
In addition to the described methods, the present invention also relates to an exhaust gas purification system for the purification of exhaust gases from a waste incineration plant by utilizing a sorption method in a circulating fluidized bed.
The exhaust gas purification system of the present invention comprises both dry sorption exhaust gas purification systems or semi-dry sorption exhaust gas purification systems. As an example for a semi-dry sorption exhaust gas purification system we may mention the Turbosorp® reactor (Austrian Energy & Environment/Von Roll Umwelttechnik AG).
The exhaust gas purification system according to the invention has a fluidized bed reactor and an apparatus for returning solid matter into the fluidized bed reactor. The latter are usually present in the form of a conventional solids separator as known to a person skilled in the art.
The exhaust gas purification system is characterized in that it also has an apparatus for regulating the supply of fresh sorbent as a function of the concentration of fresh sorbent and/or at least one sorbed pollutant in the recirculated solid matter.
Generally, the exhaust gas purification system comprises for this purpose an analysis device for determining the concentration of the component(s) in the recirculated solid matter. Particularly preferably, this device is an FT-NIR spectrometer.
Moreover, the exhaust gas purification system of the present invention can comprise a cyclone for the withdrawal of samples of the recirculated solid matter for determining the concentration of fresh sorbent and/or at least one sorbed pollutant. In this embodiment, the cyclone is preferably disposed on a connection duct leading from the fluidized bed reactor to the solids separator. Because of the fact that the connection duct is free from caking of the solid matter, it is ensured that the withdrawn solids sample is homogeneous. In this embodiment, the analysis device is preferably connected with the cyclone.
In order to maintain the temperature in the fluidized bed reactor constant at a specific value, water injection can additionally be provided. Depending on the sorbent used and depending on the pollutant composition, the temperature can be varied in such a way that the sorption is optimal. The temperature in the exhaust gas purification system is preferably maintained at a value of approx. 145° C.
The exhaust gas purification systems according to the invention allow a volume flow of up to 200,000 m n 3 /h feucht (m n 3 =normal cubic meters, where normal conditions are understood to mean a temperature of 273.15 K (0° C.) and a pressure of 101.3 kPa). The exhaust gas purification systems are generally designed for exhaust gases having an inlet temperature of from 170° C. to 300° C., in particular 180° C. to 250° C. Process water is usually used as a method for conditioning. The mean flow velocity in the fluidized bed reactor of the exhaust gas purification system is generally approx. 4 m/s. The pressure drop in the exhaust gas purification system is generally of 20 to 25 mbar.
In general, the exhaust gas purification systems are designed for an operation between 60 to 110% load of the preceding combustion system.
Table 1 shows the pollutant content of an exemplary raw gas, which can be purified with the exhaust gas purification system. In the table, the pollutant content is given as nominal daily mean value and as maximum half-hourly mean value. The exemplary raw gas according to Table 1 has an O 2 content of 11 vol.-% and a moisture content of 30 vol.-% H 2 O.
TABLE 1
Pollutant
Nominal daily mean
Maximum half-hourly
component
value
mean value
Dust
≦4000
mg/m n 3
≦10000
mg/m n 3
HCl
≦3500
mg/m n 3
≦4500
mg/m n 3
HF
≦10
mg/m n 3
≦25
mg/m n 3
SO 2
≦600
mg/m n 3
≦1000
mg/m n 3
Hg
≦0.25
mg/m n 3
≦0.5
mg/m n 3
Cd and Tl
≦1
mg/m n 3
≦2.5
mg/m n 3
Dioxin
≦5
mg/m n 3 TEQ*
≦12.5
mg/m n 3 TEQ*
*TEQ = Toxicity Equivalent
By purifying the raw gas in the exhaust gas purification system according to the invention, the pollutant content of the pure gas can be reduced to the values indicated in Table 2.
TABLE 2 Pollutant component Nominal daily mean value Dust ≦5 mg/m n 3 HCl ≦10 mg/m n 3 HF ≦1 mg/m n 3 SO 2 ≦10 mg/m n 3 Hg ≦0.03 mg/m n 3 Cd and Tl ≦0.05 mg/m n 3 Sb, As, Pb, Cr, Co, Cu, Mn, ≦0.5 mg/m n 3 Ni, V, Sn, Se, Te Dioxin ≦0.1 mg/m n 3
In the case of an optimal operation, the HCl content can be reduced noticeably below 10 mg/m n 3 and the dust content to 2 to 3 mg/m n 3 .
The mean consumption of hydrated lime depends on the pollutant loads of the raw gas and the limit values to be complied with.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be explained in more detail with reference to the figures, in which, in purely schematic form:
FIG. 1 shows an exhaust gas purification system comprising a fluidized bed reactor and a solids separator arranged downstream thereof for carrying out the method according to the invention; and
FIG. 2 shows the exhaust gas purification system according to FIG. 1 , wherein a cyclone for withdrawing a solids sample, which is shown enlarged in an inset, is arranged between the fluidized bed reactor and the solids separator.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The exhaust gas purification system 2 shown in FIG. 1 comprises a raw gas inlet 4 , through which the exhaust gas generated during the waste combustion is introduced, and a pure gas outlet 6 , through which the purified exhaust gas from the exhaust gas purification system 2 is discharged. The raw gas inlet 4 comprises an inlet socket 10 and an inlet duct 12 connected thereto downstream, which opens out into the fluidized bed reactor 14 . The fluidized bed reactor 14 has essentially the shape of a hollow cylinder which tapers conically at the inlet side. A sorbent supply line 18 for injecting the sorbent is arranged in the conically tapering region 16 . The sorbent is entrained by the exhaust gas flowing into the fluidized bed reactor 14 and forms with the fly ash and the fuel particles carried along in the exhaust gas stream from the waste combustion a circulating fluidized bed (not shown). In the upper region, the fluidized bed reactor 14 opens out into a connection duct 22 leading to the solids separator 20 . The solids separator 20 has in the upper region a filter system 24 for separating the solid particles carried along in the exhaust gas stream. The filter system 24 comprises a multiplicity of fabric bag filters 24 ′. Subsequent to passing the filter system 24 , the pure gas obtained is discharged through the pure gas outlet 6 . The separated solid particles sediment at the downwardly inclined base 26 of the solids separator 20 and flow along the base 26 into a solids recirculation channel 28 . The solids recirculation channel 28 has a metering member 29 , via which the volume flow of solid matter returned into the fluidized bed reactor 14 can be adjusted. A discharge duct 30 which comprises a conveying device 32 for discharging solid matter branches off from the return duct 28 . An analysis device 34 for determining the concentration of at least one component in the recirculated solid matter is disposed on the solids separator 20 . The supply of sorbent per time unit is increased, reduced or held constant, depending on the value obtained during the determination.
To ensure that the temperature in the exhaust gas purification system 2 does not exceed a predetermined value, water can be injected for cooling purposes into the fluidized bed reactor. For this, underneath the sorbent supply line 18 , the fluidized bed reactor 14 has a water supply line 36 comprising a nozzle head 38 , which leads into the fluidized bed reactor 14 .
In the exhaust gas purification system 2 shown in FIG. 2 , a cyclone 40 is disposed on the connection duct 22 arranged between the fluidized bed reactor 14 and the solids separator 20 for withdrawing a sample of the recirculated solid matter. During the withdrawal, the sample is injected through a withdrawal duct 42 and a tangential inlet nozzle 44 adjoining thereto into the hollow cylindrical upper portion 46 of the cyclone 40 . Owing to their mass the solid particles are, as a result of the centrifugal force, guided on spiral paths to a conically tapering lower portion 48 which opens out into a collection container 50 . From the solids sample 51 obtained in the collection container 50 , the concentration of at least one component is determined using a corresponding analysis device (not shown). In the embodiment shown in FIG. 2 , this analysis device is normally connected with the collection container 50 of the cyclone 40 . The collection container 50 has a base 52 , which can be shifted in such a way that a passage is created between the collection container 50 and the connection duct 22 , through which the solid matter in the collection container 50 returns into the connection duct 22 and consequently to the circulation again. The gaseous component being freed from the solids in the cyclone 40 is captured by a central ascending stream and passed through an immersion tube 56 into a cyclone discharge duct 58 , through which, controlled by a valve 60 , it is returned into the connection duct 22 . | The present disclosure relates to a method for purifying exhaust gases from a waste incineration plant by utilizing a sorption method in a circulating fluidized bed. According to the disclosure, the mass flow of the supplied fresh sorbent is regulated as a function of the concentration of fresh sorbent and/or at least one sorbed pollutant in the recirculated solid matter. | 1 |
TECHNICAL FIELD
[0001] This invention relates to color correcting images.
TECHNICAL FIELD
[0002] During postproduction of image files, including still images as well as image sequences comprising movies or television shows, color correction often occurs to compensate for variations in the captured material (i.e. film errors, white balance, varying lighting conditions) or to influence the viewer's “mood” to match the creative intent of a scene and/or to establish a desired “look”. Color correction operations limited to certain small areas in the image bear the designation “secondary color correction”. Secondary color correction typically consumes substantial computational resources and often take a long time.
[0003] Secondary color correction often makes use of a color mask to separate those areas for which color correction should occur as compared to the areas whose color properties should remain untouched. Typical color making techniques make use of the image color space characterized by the Hue, Saturation and Lightness (HSL) or Hue, Saturation, and Value (HSV) coordinates. The HSL and HSV color coordinate systems both make use of cylindrical geometries, with the angular axis representing hue, starting with red (0 degrees), green (120 degrees) and blue (240 degrees), whereas the radial axis represents hue. In the case of the HSL color coordinate, the vertical axis represents lightness (e.g., luminance), whereas in the HSV color coordinate system, the vertical axis represents value. Using one of the HSL or HSV color coordinate systems, a set of distance metrics (i.e. Euclidian distances) from a single or a set of RGB-color points can define a desired color range. The colors that lie inside theses distance metrics become the selected color range and form the desired color mask. Modifying the distance metrics serves to expand or reduce the colors falling into the selected color range defining the desired color mask. For example expanding or reducing the distances along a separate one of the three axes in the HSL color coordinate system serves to adjust hue, saturation and luminance, respectively. In addition to defining the colors that lie fully inside the selected color range, it is also possible to define a blend or “feather” a zone that lies at the border of the selection area.
[0004] Traditionally, defining color masks in either the HSL or HSV color coordinate system requires an iterative process that becomes slower with the addition of each new color. Thus a need exists for an improved masking process that does not suffer from the disadvantages of the prior art.
BRIEF SUMMARY OF THE INVENTION
[0005] Briefly, in accordance with an illustrative embodiment of the present principles, a method for correcting colors in an image commences by first defining a set of Red-Green-Blue (RGB) color triplets corresponding to user-selected colors defining a designated area of interest in the image to undergo color correction. The set of RGB color triplets are mapped into in a color space defined by cylindrical coordinates to create a three-dimensional look-up table (3D-LUT) that represents a first color range for the designated area of interest. The 3D-LUT undergoes adjustment to establish a second color range. Thereafter, the image is rendered using the 3D-LUT to replace colors in the designated area of interest with colors in the second color range.
BRIEF SUMMARY OF THE DRAWINGS
[0006] FIG. 1 depicts a block schematic diagram of an illustrative embodiment of apparatus for performing color correction in accordance with the present principles;
[0007] FIG. 2 depicts a screen display generated by the apparatus of FIG. 1 in connection with setting a color mask for a designated area of interest in an image for performing color correction in accordance with the present principles;
[0008] FIG. 3 depicts a screen display generated by the apparatus of FIG. 1 in connection with expansion of a set of manually picked colors for the designated area of interest in FIG. 2 ;
[0009] FIG. 4 depicts a screen display generated by the apparatus of FIG. 1 illustrating a 3-Dimensional Look-Up Table (3D-LUT) generated in connection with setting the color mask of FIG. 2 ;
[0010] FIG. 5 depicts a screen display generated by the apparatus of FIG. 1 illustrate mapping of colors using the 3D-LUT of FIG. 4 ;
[0011] FIG. 6 depicts a screen display generated by the apparatus of FIG. 1 in connection color correction of designated area of interest in the image using the 3D-LUT of FIG. 4 ;
[0012] FIG. 7 depicts a small portion of the screen display of FIG. 6 showing the same color the same color as selected in FIG. 7 but with expanded luminance; and
[0013] FIG. 8 depicts a small portion of the screen display of FIG. 6 showing the same color the same color as selected in FIG. 7 selection but with expanded luminance and a feather.
DETAILED DESCRIPTION
[0014] FIG. 1 depicts a block schematic diagram of a system 10 for performing color correction on at least a designated area of interest within an image in accordance with a preferred embodiment of the present principles. The apparatus 10 includes a processor 12 , typically in the form of a personal computer (PC), e.g., a laptop or desktop computer, having one or more microprocessors (not shown) and one or more Graphical Processing Units (GPUs), along with internal memory (not shown), including Random Access Memory (RAM) and Read Only Memory (ROM). The GPU(s) could exist as part of the functionality of the microprocessor(s) or as separate stand-alone device embodied within the processor 12 .
[0015] The processor 12 receives input information from one or more data input devices, such as keyboard 14 and mouse 16 through which an operator can enter commands and/or data. Although not shown, the processor 12 could also receive input signals through a 9-axis controller of the type commonly employed in color correction systems. The processor 12 displays output information via a display 17 device as well known in the art. The display device 17 could comprise a touch-screen device to allow data entry but such functionality is optional and not mandatory. A network interface device 18 connects the processor 12 to a network, for example a Local Area Network (LAN), Wide Area Network (WAN) or the Internet. While FIG. 1 depicts the network interface device 18 as external to the processor 12 , in practice, such functionality could exist within the processor 12 .
[0016] The processor 12 has access to at least one storage device 20 , typically in the form of a hard disk drive or the like, storing data and/or program instructions. In practice, the storage device 20 stores image information, typically in the form of one or more still images, or a succession of images (video) to undergo color correction in the manner described hereinafter. The program instruction typically include an operating such as the Microsoft Windows® operating system as well as one or more application programs, including an application program for color correction modified in accordance with the present principles.
[0017] Although not shown, the processor 12 can access other storage devices For example, the processor 12 could access a CD-ROM, DVD, a read-only and/or DVD drive and/or a DVD Read/Write drive, all known in the art. Further, the processor 12 could access one or more Universal Serial Bus (USB)-type storage devices (e.g., “memory sticks.”) through corresponding USB ports (not shown).
[0018] To carry out color correction (sometimes referred to as color grading), the processor 12 makes use of commercial color grading software, modified in accordance with the present principles, as described hereinafter. In the illustrated embodiment, the processor 12 makes use of the CineStyle Color Assist color grading software, previously available from Technicolor, Hollywood, Calif., modified as discussed hereinafter. Other commercially available color grading programs include Color Finesse, available from Synthetic Aperture, DaVinci Resolve, available from Black Magic Design, and Magic Bullet Colorista II from Red Giant Software.
[0019] To better understand the manner in which the system 10 of FIG. 1 accomplishes color correction in accordance with the present principles, refer to FIG. 2 , which depicts a screen shot 200 displayed by the touch screen display 17 of FIG. 1 in connection with execution of the CineStyle Color Assist color grading (color correction) software. The screen shot 200 of FIG. 2 includes a first display area 202 that displays the image, either a complete frame of the still image or a selected image frame of a sequence of images of a video stream, for example a movie or a television program. Additionally, the screen shot 200 of FIG. 2 includes a second display area 203 that displays a control panel associated with the CineStyle Color Assist color grading software program for enabling a user to select an area of interest within the display area 202 for color correction (“secondary color correction”). The control panel depicted in the display area 203 of FIG. 2 includes adjustment settings for different looks, color controls, keys and curves, for example. Additionally, the control panel depicted in the display area 203 of FIG. 2 includes a color selection sub-control panel 204 . The color selection sub-control panel 204 depicted in the sub-display area 203 has settings, which allows the user to select color(s) specified by RGB color triplets to create a 3-Dimensional Look-Up Table (3D-LUT) in accordance with the present principles. The 3D-LUT functions as a color mask for performing color correction.
[0020] To understand the process of creating the 3D-LUT, assume for purposes of discussion that the user wants to change the color of the dress worn by the woman appearing in the image displayed in the display area 202 of FIG. 2 . (Thus, the woman's dress in the display area 202 constitutes the area of interest for color correction). To select the color of the dress, the user simply clicks with the mouse anywhere on the dress to capture a shade of the red color. The user can then use the controls provided in the sub-display 204 to change the color (to green in this example) or expand/shrink the selection of colors. The women's dress appears as the matte area in the display area 206 .
[0021] To create the 3D-LUT, the user will select a set of RGB color triplets from the image to define the desired color for correction (i.e., the color of the woman's dress in the image displayed in the display area 202 of FIG. 2 ). Thereafter, the processor 12 of FIG. 1 converts the RGB triplets into the HSV color space system described previously. The user can easily manipulate the hue, saturation and value (luminance) parameters by using the control sub-panel depicted in the sub-display area 204 . Converting the RGB triplets into the HSV color coordinate system creates a 3D-LUT depicted in the window 208 in the sub-display area 204 of FIG. 3 . This 3D-LUT contains only the “masked” color(s), thus defining the desired color mask. In addition to using the control sub-panel 204 to manipulate hue, saturation and value (luminance) parameters, the user can interactively add or subtract RGB triplets in the linked list.
[0022] As discussed above, the user selects the color(s) used as a color mask by selecting a set of RGB triplets (sometimes referred to as a linked list of RGB points) stored by the processor 12 of FIG. 1 . By mapping the user selected set of RGB triplets (i.e., the linked list of RGB points) into the HSV color space, the processor 12 thus creates the 3D-LUT of the present principles. To avoid hard edges or contours which can occur when a pixel in the image falls inside the specified color range and a neighboring pixel falls outside the range, the user can specify “feathering” or fall-off effect to control how sharply or gently to apply the color correction inside the specified color range so color correction tapers off for pixels whose color falls outside the range. FIG. 3 depicts a portion of the screen shot 200 showing only display area 204 and sub-display area 208 , as well as the display area 206 to illustrate how the user can adjust the various setting appearing in the display area 204 to accomplish such feathering.
[0023] By replacing the color(s) specified in the 3D-LUT with new colors, the user can accomplish color correction of the designated area of interest in the image using the 3D-LUT of the present principles. FIG. 4 depicts the window 208 in the sub-display area 204 of FIG. 2 following a mapping of selected new colors the 3D-LUT. As depicted in FIG. 4 , the user has rotated the 3D-LUT in the display area 208 in a different orientation as compared to the orientation of the 3D-LUT in FIG. 3 . By rotating the 3D-LUT, the user can visually inspect the 3D-LUT from different angles to identify colors accidentally picked.
[0024] To summarize, using the color grading software executed by the processor 12 , the user creates the 3D-LUT via the following steps
[0025] 1) The user selects the color(s) that define a color mark for secondary color correction in an area of interest in the image.
[0026] 2) The processor 12 establishes a set of RGB triplets defining the color mask for subsequent storage in a list. The user can augment this list by adding colors from the image.
[0027] 3) The processor 12 maps the RGB triplet point cloud into the HSV color space to create the 3D-LUT.—The user can easily manipulate the 3D-LUT in this color space by adjusting the hue, saturation and luminance axis via the control on the sub-panel 204 .
[0028] The resulting 3D-LUT contains only the masked colors, which can creatively be replaced by new colors.
[0029] During playback of the image, the processor 12 can apply the 3D-LUT created in the manner described to the image in real-time using tri-linear interpolations algorithms for pixel shaders embodied with in GPUs in the processor 12 to perform the desired color correction. FIG. 5 depicts the results of color selection and replacement using the 3D-LUT. In comparison to FIG. 2 , the color of the woman's dress in the display area 202 of FIG. 5 changes in accordance with color correction obtained using the 3D-LUT to map new colors for the existing colors in the designated region of interest.
[0030] FIG. 6 depicts a portion of the color inside the 3D-LUT in the display area 208 of FIG. 5 showing replacement with a different color.
[0031] FIG. 7 depicts a portion of the color inside the 3D-LUT in the display area 208 of FIG. 5 showing the same color as FIG. 6 with expanded luminance selected by the user. FIG. 8 depicts a portion of the color inside the 3D-LUT in the display area 208 of
[0032] FIG. 5 showing the same color as FIG. 6 with expanded luminance and feathering
[0033] Using the 3D-LUT created in the manner described above achieves a dramatic speed improvement and enables color correction in real-time. Using the 3D-LUT of the present principles affords the advantage that the processing time remains linear regardless of the number of colors in the selected mask. Prior art solutions used iterative algorithms, which caused decrease in speed with the addition of more mask colors.
[0034] The foregoing describes a method and apparatus for color correcting images. While the color correction technique of the present principles has been described in connection with the CineStyle Color Assist color grading software program, those skilled in the art should readily appreciate that other color grading (color correction) software programs could serve the same function. In other words, such other color grading programs could readily undergo modification to create a color mask from a 3D-LUT obtained by mapping a user-selected set of RGB triplets into a color space such as HSL or HSV in accordance with the present principles. | A method for correcting colors in an image commences by first defining a set of Red-Green-Blue (RGB) color triplets corresponding to user-selected colors defining a designated are of interest in the image to undergo color correction. The set of RGB color triplets are mapped into in a color space defined by cylindrical coordinates to create a three-dimensional look-up table (3D-LUT) that represents a first color range for the designated area of interest. The 3D-LUT undergoes adjustment to establish a second color range. Thereafter, the image is rendered using the 3D-LUT to replace colors in the designated area of interest with colors in the second color range. | 6 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. Provisional Patent Application No. 61/310,719, filed on Mar. 5 th , 2010. This application is hereby incorporated by this reference in their entireties for all of its teachings.
TECHNICAL FIELD
[0002] This disclosure generally relates to compound and their synthesis. More particularly, this disclosure relates to treating mammals affected by metal accumulation in blood and other organs with pharmaceutically acceptable amount of compounds, composition and the prodrugs of the compound.
BACKGROUND ART
[0003] Metal toxicity may occur due to essential metal overload or exposure to heavy metals from various sources. Most metals are capable of forming covalent bonds with carbon, resulting in metal-organic compounds. Metals and metal compounds interfere with functions of various organ systems like the central nervous system (CNS), the haematopoietic system, liver, kidneys, etc. (Flora et al. 2010).
[0004] Metal accumulation has been responsible for many dysfunctions in liver diseases. Pathophysiologic mechanisms responsible for cerebral dysfunction and neuronal cell death in hepatocerebral disorders, such as Wilson's Disease, post-shunt myelopathy, hepatic encephalopathy, and acquired non-Wilsonian hepatocerebral degeneration are a major feature of hepatocerebral disorders. Morphologic changes to astrocytes (Alzheimer type II astrocytosis) include neurotoxic effects of metals such as copper, manganese, and iron. Management and treatment of hepatocerebral disorders include chelation therapy (Wilson's Disease) and liver transplantation among others. There is a need for a development of new copper chelator and an anticancer metallodrug with improved specificity and decreased toxic side effects.
SUMMARY OF DISCLOSURE
[0005] In one embodiment, a compound comprising of Formula 1 (also mentioned as formula 1) is disclosed.
[0000]
[0006] Another embodiment, a pharmaceutical acceptable composition comprising of one or more compounds of formula 1, an intermediate, a prodrug, pharmaceutical acceptable salt of compound formula 1 with one or more of pharmaceutically acceptable carriers, and vehicles or diluents are disclosed. These compositions may be used in the treatment of diseases related affected by metal accumulation in blood and other organs.
[0007] In another embodiment, the present disclosure relates to the compound and composition of formula 1, or pharmaceutically acceptable salts thereof,
[0000]
[0000] Wherein, R 1 , R 2 , and R 3 each independently represents hydrogen, thiol, alkyl, alkyl thiol, acetyl thiol, disulfide, acyl, acylalkyl, alkenyl, alkylthioalkyl, alkynyl, alkoxyaryl, alkoxyalkyl, aryl, aralkyl, aryloxyalkyl, arylthioalkyl, cycloalkyl, ether, ester, heteroaryl, heterocyclyl, lower alkyl, sulfone, sulfoxide, or hydroxyalkyl; and
R 4 may be at least one of a residue of guanidine, a residue of hydrazine, an acid, a residue of pyruvic acid, a residue of oxaloacetic acid, a residue of tocopherol, a residue of ascorbic acid, a residue of thiamine, thioctic acid, a residue of thioctic acid, a residue of acetyl cysteine, a residue of alpha-keto glutaric acid, a residue of dimercaprol, a residue of an NO donor, lipoic acid, a residue of glutathione, (RS)-2,3-disulfanylpropan-1-ol and an analog of any one of the foregoing.
[0000]
[0008] In another embodiment, R 1 , R 2 and R 3 represents, hydrogen, methyl, ethyl or thiol and R 4 represents (RS)-2,3-disulfanylpropan-1-ol.
[0009] Furthermore, in another embodiment is disclosed as a pharmaceutically acceptable composition, a pharmaceutically acceptable salt of the compound of formula 1 comprising:
[0010] a) R-(+)-lipoic acid (or) Acetylcysteine (or) Dimercaprol;
[0011] b) Zinc acetate (or) Triethylene tetramine; and
[0012] c) a compound of Formula 1
[0000]
[0000] Wherein, R 1 , R 2 , and R 3 each independently represents hydrogen, thiol, alkyl, alkyl thiol, acetyl thiol, disulfide, acyl, acylalkyl, alkenyl, alkylthioalkyl, alkynyl, alkoxyaryl, alkoxyalkyl, aryl, aralkyl, aryloxyalkyl, arylthioalkyl, cycloalkyl, ether, ester, heteroaryl, heterocyclyl, lower alkyl, sulfone, sulfoxide, or hydroxyalkyl; and
R 4 represents at least one of a residue of guanidine, a residue of hydrazine, an acid, a residue of pyruvic acid, a residue of oxaloacetic acid, a residue of tocopherol, a residue of ascorbic acid, a residue of thiamine, thioctic acid, a residue of thioctic acid, a residue of acetyl cysteine, a residue of alpha-keto glutaric acid, a residue of dimercaprol, a residue of an NO donor, a residue of glutathione and an analog of any one of the foregoing.
[0013] In one embodiment the pharmaceutically acceptable amount may be administered, but not limited to, as an injection. Other embodiments for administration may include peroral, topical, transmucosal, inhalation, targeted delivery and sustained release formulations.
[0014] Herein, the application additionally provides a kit comprising the pharmaceutical compositions described herein. The kit may further comprise instructions for use in the treatment of diseases related to free metal accumulation toxicity in the blood physiology leading to various chronic physiological and biochemical abnormalities such as kidney failure, free radicals accumulation or related complications. In another embodiment, formula 1 may function as an anti-copper agent that is highly specific for the reduction of free copper in serum, the most toxic form of copper in the body, and is thus ideally suited for the treatment of central nervous system (CNS) diseases in which abnormal serum and CNS copper homeostasis are implicated.
[0015] Furthermore, herein is provided a kit comprising a composition comprising of: a) at least one of R-(+)-lipoic acid, acetylcysteine and dimercaprol; b) a compound of formula 1 and c) at least one of triethylene tetramine, zinc acetate and ammonium tetrathiomolybdate:
[0000]
[0016] Wherein, R 1 , R 2 , and R 3 each independently represents hydrogen, thiol, alkyl, alkyl thiol, acetyl thiol, disulfide, acyl, acylalkyl, alkenyl, alkylthioalkyl, alkynyl, alkoxyaryl, alkoxyalkyl, aryl, aralkyl, aryloxyalkyl, arylthioalkyl, cycloalkyl, ether, ester, heteroaryl, heterocyclyl, lower alkyl, sulfone, sulfoxide, or hydroxyalkyl; and
[0000] R 4 represents at least one of a residue of guanidine, a residue of hydrazine, an acid, a residue of pyruvic acid, a residue of oxaloacetic acid, a residue of tocopherol, a residue of ascorbic acid, a residue of thiamine, thioctic acid, a residue of thioctic acid, a residue of acetyl cysteine, a residue of alpha-keto glutaric acid, a residue of dimercaprol, a residue of an NO donor, a residue of glutathione, RS)-2,3-disulfanylpropan-1-ol, and an analog of any one of the foregoing.
[0017] Additionally, in another embodiment the instant application discloses several methods of synthesizing the composition of formula I.
[0018] In another embodiment, R-lipoic acid, Dimercaprol, Zinc acetate, Ammonium tetrathiomolybdate or triethylene tetramine is combined with a pharmaceutically acceptable salt of the compound of formula 1.
[0019] The compound, composition, method of synthesis, and treatment disclosed herein may be implemented in any means for achieving various aspects, and may be executed in a form suitable for the mammal. Other features will be apparent from the accompanying detailed description that follows.
BRIEF DESCRIPTION OF DRAWINGS
[0020] Figure one shows one method of synthesizing a compound represented by formula 1.
[0021] FIG. 2 shows another method of synthesizing the compound represented by formula 1 and protection of aminothiol intermediate compound 2 is different from earlier, i.e., Trityl group used instead of thiazolidine.
[0022] FIG. 3 , shows another method of the synthesis of compound represented by formula 1 and (1,3-dithiolane-4-yl)methanol intermediate used instead of (2,2-dimethyl-1,3-dithiolan-4-yl)methanol at step-4.
DETAILED DESCRIPTION
[0023] In the present disclosure metal chelating compound, composition, synthesis of the compound and a kit for treatment are disclosed. The compound comprises of formula 1. Furthermore, the composition comprises of R-lipoic acid, dimercaprol, zinc acetate, ammonium tetrathiomolybdate or triethylene tetramine are combined with a pharmaceutically acceptable salt of the compound of formula 1. In another embodiment, several methods of synthesizing the formula 1 are disclosed.
[0024] The compound may also comprise of tartrate, esylate, mesylate, hydrate, solvate hydrochloride and sulfate salts of formula 1. Herein the disclosure also provides a kit comprising any of the pharmaceutical compositions disclosed herein. The kit may comprise instructions for use in the treatment of diseases for mammals associated to metal accumulation and related complications.
DEFINITIONS
[0025] As used herein, the following terms and phrases shall have the meanings set forth below. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art.
[0026] The term “alkyl” refers to the radical of saturated aliphatic groups, including straight-chain alkyl groups, branched-chain alkyl groups, cycloalkyl (alicyclic) groups, alkyl-substituted cycloalkyl groups, and cycloalkyl-substituted alkyl groups. In preferred embodiments, a straight chain or branched chain alkyl has 30 or fewer carbon atoms in its backbone (e.g., C 1 -C 30 for straight chains, C 3 -C 30 for branched chains), and more preferably 20 or fewer. Likewise, preferred cycloalkyls have from 3-10 carbon atoms in their ring structure, and more preferably have 5, 6 or 7 carbons in the ring structure.
[0027] The term “alkyl” as used herein refers to a saturated linear or branched-chain monovalent hydrocarbon radical of one to twelve carbon atoms. Examples of alkyl groups include, but are not limited to, methyl(Me, —CH 3 ), ethyl(Et, —CH 2 CH 3 ), 1-propyl (n-Pr, n-propyl, —CH 2 CH 2 CH 3 ), 2-propyl(i-Pr, i-propyl, —CH(CH 3 ) 2 ), 1-butyl(n-Bu, n-butyl, —CH 2 CH 2 CH 2 CH 3 ), 2-methyl-1-propyl(i-Bu, i-butyl, —CH 2 CH(CH 3 ) 2 ), 2-butyl(s-Bu, s-butyl, —CH(CH 3 )CH 2 CH 3 ), 2-methyl-2-propyl(t-Bu, t-butyl, —C(CH 3 ) 3 ), 1-pentyl (n-pentyl, —CH 2 CH 2 CH 2 CH 2 CH 3 ), 2-pentyl (—CH(CH 3 )CH 2 CH 2 CH 3 ), 3-pentyl (—CH(CH 2 CH 3 ) 2 ), 2-methyl-2-butyl (—C(CH 3 ) 2 CH 2 CH 3 ), 3-methyl-2-butyl (—CH(CH 3 )CH(CH 3 ) 2 ), 3-methyl-1-butyl (—CH 2 CH 2 CH(CH 3 ) 2 ), 2-methyl-1-butyl (—CH 2 CH(CH 3 )CH 2 CH 3 ), 1-hexyl (—CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 ), 2-hexyl (—CH(CH 3 )CH 2 CH 2 CH 2 CH 3 ), 3-hexyl (—CH(CH 2 CH 3 )(CH 2 CH 2 CH 3 )), 2-methyl-2-pentyl (—C(CH 3 ) 2 CH 2 CH 2 CH 3 ), 3-methyl-2-pentyl (—CH(CH 3 )CH(CH 3 )CH 2 CH 3 ), 4-methyl-2-pentyl (—CH(CH 3 )CH 2 CH(CH 3 ) 2 ), 3-methyl-3-pentyl (—C(CH 3 )(CH 2 CH 3 ) 2 ), 2-methyl-3-pentyl (—CH(CH 2 CH 3 )CH(CH 3 ) 2 ), 2,3-dimethyl-2-butyl (—C(CH 3 ) 2 CH(CH 3 ) 2 ), 3,3-dimethyl-2-butyl (—CH(CH 3 )C(CH 3 ) 3 , 1-heptyl, 1-octyl, and the like. [0014] The term “alkenyl” refers to linear or branched-chain monovalent hydrocarbon radical of two to twelve carbon atoms with at least one site of unsaturation, i.e., a carbon-carbon, sp double bond, wherein the alkenyl radical includes radicals having “cis” and “trans” orientations, or alternatively, “E” and “Z” orientations. Examples include, but are not limited to, ethylenyl or vinyl (—CH═CH 2 ), allyl (—CH 2 CH═CH 2 ), and the like. The term “alkynyl” refers to a linear or branched monovalent hydrocarbon radical of two to twelve carbon atoms with at least one site of unsaturation, i.e., a carbon-carbon, sp triple bond. Examples include, but are not limited to, ethynyl (—C≡CH), propynyl(propargyl, —CH 2 C≡CH), and the like.
[0028] Moreover, the term “alkyl” (or “lower alkyl”) as used throughout the specification, examples, and claims is intended to include both “unsubstituted alkyls” and “substituted alkyls”, the latter of which refers to alkyl moieties having substituents replacing a hydrogen on one or more carbons of the hydrocarbon backbone. Such substituents, if not otherwise specified, may include, for example, a halogen, a hydroxyl, a carbonyl (such as a carboxyl, an alkoxycarbonyl, a formyl, or an acyl), a thiocarbonyl (such as a thioester, a thioacetate, or a thioformate), an alkoxyl, a phosphoryl, a phosphate, a phosphonate, a phosphinate, an amino, an amido, an amidine, an imine, a cyano, a nitro, an azido, a sulfhydryl, an alkylthio, a sulfate, a sulfonate, a sulfamoyl, a sulfonamido, a sulfonyl, a heterocyclyl, an aralkyl, or an aromatic or heteroaromatic moiety. It will be understood by those skilled in the art that the moieties substituted on the hydrocarbon chain may themselves be substituted, if appropriate. For instance, the substituents of a substituted alkyl may include substituted and unsubstituted forms of amino, azido, imino, amido, phosphoryl (including phosphonate and phosphinate), sulfonyl (including sulfate, sulfonamido, sulfamoyl and sulfonate), and silyl groups, as well as ethers, alkylthios, carbonyls (including ketones, aldehydes, carboxylates, and esters), —CF 3 , —CN and the like. Exemplary substituted alkyls are described below. Cycloalkyls may be further substituted with alkyls, alkenyls, alkoxys, alkylthios, aminoalkyls, carbonyl-substituted alkyls, —CF 3 , —CN, and the like.
[0029] The term “acyl” is art-recognized and refers to a group represented by the general formula hydrocarbylC(O)-, preferably alkylC(O)-.
[0030] “Aryl” means a monocyclic or polycyclic ring assembly wherein each ring is aromatic or when fused with one or more rings forms an aromatic ring assembly. If one or more ring atoms is not carbon (e.g., N, S), the aryl is a heteroaryl. C x aryl and C x-Y aryl are typically used where X and Y indicate the number of carbon atoms in the ring.
[0031] The term “acylamino” is art-recognized and refers to an amino group substituted with an acyl group and may be represented, for example, by the formula hydrocarbyl C(O)NH—.
[0032] The term “acylalkyl” is art-recognized and refers to an alkyl group substituted with an acyl group and may be represented, for example, by the formula hydrocarbyl C(O)alkyl.
[0033] The term “acyloxy” is art-recognized and refers to a group represented by the general formula hydrocarbylC(O)O-, preferably alkylC(O)O-.
[0034] The term “alkoxy” refers to an alkyl group, preferably a lower alkyl group, having an oxygen attached thereto. Representative alkoxy groups include methoxy, ethoxy, propoxy, tert-butoxy and the like.
[0035] The term “alkoxyalkyl” refers to an alkyl group substituted with an alkoxy group and may be represented by the general formula alkyl-O-alkyl.
[0036] The term “alkenyl”, as used herein, refers to an aliphatic group containing at least one double bond and is intended to include both “unsubstituted alkenyls” and “substituted alkenyls”, the latter of which refers to alkenyl moieties having substituents replacing a hydrogen on one or more carbons of the alkenyl group. Such substituents may occur on one or more carbons that are included or not included in one or more double bonds.
[0037] Moreover, such substituents include all those contemplated for alkyl groups, as discussed below, except where stability is prohibitive. For example, substitution of alkenyl groups by one or more alkyl, carbocyclyl, aryl, heterocyclyl, or heteroaryl groups is contemplated.
[0038] The term “alkylamino”, as used herein, refers to an amino group substituted with at least one alkyl group.
[0039] The term “alkylthio”, as used herein, refers to a thiol group substituted with an alkyl group and may be represented by the general formula alkylS-.
[0040] The term “alkynyl”, as used herein, refers to an aliphatic group containing at least one triple bond and is intended to include both “unsubstituted alkynyls” and “substituted alkynyls”, the latter of which refers to alkynyl moieties having substituents replacing a hydrogen on one or more carbons of the alkynyl group. Such substituents may occur on one or more carbons that are included or not included in one or more triple bonds. Moreover, such substituents include all those contemplated for alkyl groups, as discussed above, except where stability is prohibitive. For example, substitution of alkynyl groups by one or more alkyl, carbocyclyl, aryl, heterocyclyl, or heteroaryl groups is contemplated.
[0041] The term “ether”, as used herein, refers to a hydrocarbyl group linked through an oxygen to another hydrocarbyl group. Accordingly, an ether substituent of a hydrocarbyl group may be hydrocarbyl-O—. Ethers may be either symmetrical or unsymmetrical. Examples of ethers include, but are not limited to, heterocycle-O-heterocycle and aryl-O-heterocycle. Ethers include “alkoxyalkyl” groups, which may be represented by the general formula alkyl-O-alkyl.
[0042] The terms “halo” and “halogen” as used herein means halogen and includes chloro, fluoro, bromo, and iodo.
[0043] The terms “hetaralkyl” and “heteroaralkyl”, as used herein, refers to an alkyl group substituted with a hetaryl group.
[0044] The term “heteroalkyl”, as used herein, refers to a saturated or unsaturated chain of carbon atoms and at least one heteroatom, wherein no two heteroatoms are adjacent.
[0045] The terms “heteroaryl” and “hetaryl” include substituted or unsubstituted aromatic single ring structures, preferably 5- to 7-membered rings, more preferably 5- to 6-membered rings, whose ring structures include at least one heteroatom, preferably one to four heteroatoms, more preferably one or two heteroatoms. The terms “heteroaryl” and “hetaryl” also include polycyclic ring systems having two or more cyclic rings in which two or more carbons are common to two adjoining rings wherein at least one of the rings is heteroaromatic, e.g., the other cyclic rings may be cycloalkyls, cycloalkenyls, cycloalkynyls, aryls, heteroaryls, and/or heterocyclyls. Heteroaryl groups include, for example, pyrrole, furan, thiophene, imidazole, oxazole, thiazole, pyrazole, pyridine, pyrazine, pyridazine, and pyrimidine, and the like.
[0046] The term “heteroatom” as used herein means an atom of any element other than carbon or hydrogen. Preferred heteroatoms are nitrogen, oxygen, and sulfur.
[0047] The terms “heterocyclyl”, “heterocycle”, and “heterocyclic” refer to substituted or unsubstituted non-aromatic ring structures, preferably 3- to 10-membered rings, more preferably 3- to 7-membered rings, whose ring structures include at least one heteroatom, preferably one to four heteroatoms, more preferably one or two heteroatoms. The terms “heterocyclyl” and “heterocyclic” also include polycyclic ring systems having two or more cyclic rings in which two or more carbons are common to two adjoining rings wherein at least one of the rings is heterocyclic, e.g., the other cyclic rings may be cycloalkyls, cycloalkenyls, cycloalkynyls, aryls, heteroaryls, and/or heterocyclyls. Heterocyclyl groups include, for example, piperidine, piperazine, pyrrolidine, morpholine, lactones, lactams, and the like.
[0048] The term “heterocyclylalkyl”, as used herein, refers to an alkyl group substituted with a heterocycle group.
[0049] The term “hydrocarbyl”, as used herein, refers to a group that is bonded through a carbon atom that does not have a ═O or ═S substituent, and typically has at least one carbon-hydrogen bond and a primarily carbon backbone, but may optionally include heteroatoms. Thus, groups like methyl, ethoxyethyl, 2-pyridyl, and trifluoromethyl are considered to be hydrocarbyl for the purposes of this application, but substituents such as acetyl (which has a ═O substituent on the linking carbon) and ethoxy (which is linked through oxygen, not carbon) are not. Hydrocarbyl groups include, but are not limited to aryl, heteroaryl, carbocycle, heterocycle, alkyl, alkenyl, alkynyl, and combinations thereof.
[0050] The term “hydroxyalkyl”, as used herein, refers to an alkyl group substituted with a hydroxy group.
[0051] The term “ketone” is art-recognized and may be represented, for example, by the formula C(O)R 9 , wherein R 9 represents a hydrocarbyl group.
[0052] The term “lower” when used in conjunction with a chemical moiety, such as, acyl, acyloxy, alkyl, alkenyl, alkynyl, or alkoxy is meant to include groups where there are ten or fewer non-hydrogen atoms in the substituent, preferably six or fewer. A “lower alkyl”, for example, refers to an alkyl group that contains ten or fewer carbon atoms, preferably six or fewer. Lower alkyls include methyl and ethyl. In certain embodiments, acyl, acyloxy, alkyl, alkenyl, alkynyl, or alkoxy substituents defined herein are respectively lower acyl, lower acyloxy, lower alkyl, lower alkenyl, lower alkynyl, or lower alkoxy, whether they appear alone or in combination with other substituents, such as in the recitations hydroxyalkyl and aralkyl (in which case, for example, the atoms within the aryl group are not counted when counting the carbon atoms in the alkyl substituent).
[0053] The term “substituted” refers to moieties having substituents replacing hydrogen on one or more carbons of the backbone. It will be understood that “substitution” or “substituted with” includes the implicit proviso that such substitution is in accordance with permitted valence of the substituted atom and the substituent, and that the substitution results in a stable compound, e.g., which does not spontaneously undergo transformation such as by rearrangement, cyclization, elimination, etc. As used herein, the term “substituted” is contemplated to include all permissible substituents of organic compounds. In a broad aspect, the permissible substituents include acyclic and cyclic, branched and unbranched, carbocyclic and heterocyclic, aromatic and non-aromatic substituents of organic compounds. The permissible substituents may be one or more and the same or different for appropriate organic compounds. For purposes of this application, the heteroatoms such as nitrogen may have hydrogen substituents and/or any permissible substituents of organic compounds described herein which satisfy the valences of the heteroatoms. Substituents may include any substituents described herein, for example, a halogen, a hydroxyl, a carbonyl (such as a carboxyl, an alkoxycarbonyl, a formyl, or an acyl), a thiocarbonyl (such as a thioester, a thioacetate, or a thioformate), an alkoxyl, a phosphoryl, a phosphate, a phosphonate, a phosphinate, an amino, an amido, an amidine, an imine, a cyano, a nitro, an azido, a sulfhydryl, an alkylthio, a sulfate, a sulfonate, a sulfamoyl, a sulfonamido, a sulfonyl, a heterocyclyl, an aralkyl, or an aromatic or heteroaromatic moiety. It will be understood by those skilled in the art that the moieties substituted on the hydrocarbon chain may themselves be substituted, if appropriate.
[0054] Unless specifically stated as “unsubstituted,” references to chemical moieties herein are understood to include substituted variants. For example, reference to an “aryl” group or moiety implicitly includes both substituted and unsubstituted variants.
[0055] “Substituted or unsubstituted” means that a given moiety may consist of only hydrogen substituents through available valencies (unsubstituted) or may further comprise one or more non-hydrogen substituents through available valencies (substituted) that are not otherwise specified by the name of the given moiety. For example, isopropyl is an example of an ethylene moiety that is substituted by —CH 3 . In general, a non-hydrogen substituent may be any substituent that may be bound to an atom of the given moiety that is specified to be substituted. Examples of substituents include, but are not limited to, aldehyde, alicyclic, aliphatic, (C1-10) alkyl, alkylene, alkylidene, amide, amino, aminoalkyl, aromatic, aryl, bicycloalkyl, bicycloaryl, carbamoyl, carbocyclyl, carboxyl, carbonyl group, cycloalkyl, cycloalkylene, ester, halo, heterobicycloalkyl, heterocycloalkylene, heteroaryl, heterobicycloaryl, heterocycloalkyl, oxo, hydroxy, iminoketone, ketone, nitro, oxaalkyl and oxoalkyl moieties, each of which may optionally also be substituted or unsubstituted. In one particular embodiment, examples of substituents include, but are not limited to, hydrogen, halo, nitro, cyano, thio, oxy, hydroxy, carbonyloxy, C(1-10)alkoxy, (C4-12) aryloxy, hetero C(1-10)aryloxy, carbonyl, oxycarbonyl, aminocarbonyl, amino, C(1-10)alkylamino, sulfonamido, imino, sulfonyl, sulfinyl, C(1-10)alkyl, halo C(1-10)alkyl, hydroxy C(1-10)alkyl, carbonyl C(1-10) alkyl, thiocarbonyl C(1-10)alkyl, sulfonyl C(1-10)alkyl, sulfinyl C(1-10)alkyl, C(1-10)azaalkyl, imino C(1-10)alkyl, (C3-12) cycloalkyl(C1-5) alkyl, hetero (C3-12) cycloalkyl C(1-10)alkyl, aryl C(1-10)alkyl, hetero C(1-10)aryl(C1-5) alkyl, (C9-12) bicycloaryl(Ci_s) alkyl, hetero (C1-12) bicycloaryl C(1-5) alkyl, (C3-12) cycloalkyl, hetero (C3-12) cycloalkyl, (C9-12) bicycloalkyl, hetero (C 3-I2 ) bicycloalkyl, (C 4-I2 ) aryl, hetero C(1-10)aryl, (C9-12) bicycloaryl and hetero (C4-12) bicycloaryl. In addition, the substituent is itself optionally substituted by a further substituent. In one particular embodiment, examples of the further substituent include, but are not limited to, hydrogen, halo, nitro, cyano, thio, oxy, hydroxy, carbonyloxy, C(1-10)alkoxy, (C4-12) aryloxy, hetero C(1-10)aryloxy, carbonyl, oxycarbonyl, aminocarbonyl, amino, C(1-10) alkylamino, sulfonamido, imino, sulfonyl, sulfinyl, C(1-10)alkyl, halo C(1-10)alkyl, hydroxy C(1-10)alkyl, carbonyl C(1-10)alkyl, thiocarbonyl C(1-10)alkyl, sulfonyl C(1-10)alkyl, sulfinyl C(1-10)alkyl, C(1-10)azaalkyl, imino C(1-10)alkyl, (C 3 —I 2 ) cycloalkyl (Ci- 5 ) alkyl, hetero (C3-12) cycloalkyl C(1-10)alkyl, aryl(Ci —10 ) alkyl, hetero (Ci-io) aryl C(1-5) alkyl, C(9-12)bicycloaryl(C1-5) alkyl, hetero (C8-12) bicycloaryl(Ci_s) alkyl, (C3-12) cycloalkyl, hetero (C3-12) cycloalkyl, (C 9-12 ) bicycloalkyl, hetero (C3-12) bicycloalkyl, (C4-12) aryl, hetero C(1-10)aryl, (C9-12) bicycloaryl and hetero (C4-12) bicycloaryl.
[0056] The compounds of the present compound of formula 1 may be present in the form of pharmaceutically acceptable salts. The compounds of the present disclosure may also be present in the form of pharmaceutically acceptable esters (i.e., the methyl and ethyl esters of the acids of formula I to be used as prodrugs). The compounds of the present disclosure may also be solvated, i.e. hydrated. The solvation may be affected in the course of the manufacturing process or may take place i.e. as a consequence of hygroscopic properties of an initially anhydrous compound of formula I (hydration).
[0057] Compounds that have the same molecular formula but differ in the nature or sequence of bonding of their atoms or the arrangement of their atoms in space are termed “isomers.” Isomers that differ in the arrangement of their atoms in space are termed “stereoisomers.” Diastereomers are stereoisomers with opposite configuration at one or more chiral centers which are not enantiomers. Stereoisomers bearing one or more asymmetric centers that are non-superimposable mirror images of each other are termed “enantiomers.” When a compound has an asymmetric center, for example, if a carbon atom is bonded to four different groups, a pair of enantiomers is possible. An enantiomer may be characterized by the absolute configuration of its asymmetric center or centers and is described by the R- and S-sequencing rules of Cahn, Ingold and Prelog, or by the manner in which the molecule rotates the plane of polarized light and designated as dextrorotatory or levorotatory (i.e., as (+) or (−)-isomers respectively). A chiral compound may exist as either individual enantiomer or as a mixture thereof. A mixture containing equal proportions of the enantiomers is called a “racemic mixture”.
[0058] The term “sulfate” is art-recognized and refers to the group OSO 3 H, or a pharmaceutically acceptable salt thereof. A sulfate of compound of formula 1 or crystal thereof may be a hydrate. The number of the combined water can be controlled by varying the condition of recrystallization or drying.
[0059] As used herein, the term “metal accumulation related diseases” refers to a pathology caused by or resulting in abnormalities in metal metabolism. For example; copper toxicity related diseases include: Hepatic (cirrhosis, chronic active hepatitis, fulminant hepatic failure), Neurologic (bradykinesia, rigidity, tremor, ataxia, dyskinesia, dysarthria, seizures), Psychiatric (behavioral disturbances, cognitive impairment, psychosis), Orthalmologic (kayser-Fleischer rings, sunflow cataracts), Hematologic (haemolysis, coagulopathy), Renal (renal tubular defects, diminished glomerular filtration, nephrolithiasis), Cardiovascular (cardiomyopathy, arrhythmias, conduction disturbances, autonomic dysfunction), Musculoskeletal (osteomalacia, osteoporosis, degenerative joint diseases), Gastrointestinal (cholelithiasis, pancreatitis, bacterial peritonitis), Endocrinologic (amenorrhoea, spontaneous abortion, delayed puberty, gynecomastia), Dermatologic (hyperpigmentation, amaythosis nigrimays).
[0060] The term “polymorph” as used herein is art-recognized and refers to one crystal structure of a given compound.
[0061] “Residue” is an art-recognized term that refers to a portion of a molecule. For instance, a residue of thioctic acid may be: dihydrolipoic acid, bisnorlipoic acid, tetranorlipoic acid, 6,8-bismethylmercapto-octanoic acid, 4,6-bismethylmercapto-hexanoic acid, 2,4-bismethylmeracapto-butanoic acid, 4,6-bismethylmercapto-hexanoic acid.
[0062] The term “polymorph” as used herein is art-recognized and refers to one crystal structure of a given compound.
[0063] The term “prodrug” is intended to encompass compounds that, under physiological conditions, are converted into the therapeutically active agents of the present disclosure. A common method for making a prodrug is to include selected moieties that are hydrolyzed under physiological conditions to reveal the desired molecule. In other embodiments, the prodrug is converted by an enzymatic activity of the host animal.
[0064] The term “prophylactic or therapeutic” treatment is art-recognized and includes administration to the host of one or more of the subject compositions. If it is administered prior to clinical manifestation of the unwanted condition (e.g., disease or other unwanted state of the host animal) then the treatment is prophylactic, i.e., it protects the host against developing the unwanted condition, whereas if it is administered after manifestation of the unwanted condition, the treatment is therapeutic, (i.e., it is intended to diminish, ameliorate, or stabilize the existing unwanted condition or side effects thereof).
[0065] The term “solvate” as used herein, refers to a compound formed by solvation (e.g., a compound formed by the combination of solvent molecules with molecules or ions of the solute).
[0066] The present disclosure also contemplates prodrugs of the compositions disclosed herein, as well as pharmaceutically acceptable salts of said prodrugs.
[0067] This application also discloses a pharmaceutical composition comprising a pharmaceutically acceptable carrier and the composition of thioctic acid or a residue of thioctic acid, dimercaprol or acetylcyteine and salts of a compound of Formula 1. This application further discloses a pharmaceutical composition comprising a pharmaceutically acceptable carrier and (a) lipoic acid or residue of lipoate and (b) a compound of Formula I (c) dimercaprol or acetylcysteine or zinc acetate or ammonium thiomolybdate. The pharmaceutical composition may be formulated for systemic or topical administration. The pharmaceutical composition may be formulated for oral administration, injection, subdermal administration, or transdermal administration. The pharmaceutical composition may further comprise at least one of a pharmaceutically acceptable stabilizer, diluents, surfactant, filler, binder, and lubricant.
[0068] Additionally, the optimal concentration and/or quantities or amounts of any particular compound of formula 1 and the composition may be adjusted to accommodate variations in the treatment parameters. Such treatment parameters include the clinical use to which the preparation is put, e.g., the site treated, the type of patient, e.g., human or non-human, adult or child, and the nature of the disease or condition.
[0069] The compositions may also be used in biochemical research, for example in studying and modulating copper metabolism and homeostasis.
[0070] Generally, in carrying out the methods detailed in this application, an effective dosage for the compounds of Formula 1 is in the range of about 0.3 mg/kg/day to about 60 mg/kg/day in single or divided doses, for instance 1 mg/kg/day to about 50 mg/kg/day in single or divided doses. The compounds of Formula 1 may be administered at a dose of, for example, less than 2 mg/kg/day, 5 mg/kg/day, 10 mg/kg/day, 20 mg/kg/day, 30 mg/kg/day, or 40 mg/kg/day. Compounds of Formula 1 may also be administered to a human patient at a dose of, for example, between 50 mg and 1000 mg, between 100 mg and 800 mg, or less than 1000, 900, 800, 700, 600, 500, 400, 300, 200, or 100 mg per day. In certain embodiments, the compositions herein are administered at an amount that is less than 95%, 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, or 10% of the compound of formula 1 required for the same therapeutic benefit.
METHODS OF SYNTHESIS
Example Synthesis 1
[0071] FIG. 1 shows a five step process of producing compound formula 1
[0000] Step 1: As a first step a D-(−)-Penicillamine and Dichloromethane (DCM) were mixed together in pressure bottle containing a magnetic stirrer. The pressure bottle was securely closed with a rubber septum. The pressure bottle was further cooled in an i-PrOH/dry ice bath and kept in the dry ice bath till the following step was finished. Condensed isobutylene was transferred to the pressure bottle, using a cannula, followed by adding a few drops of sulfuric acid to the reaction mixture 1. The addition of isobutylene was continued for a period of 2 hours. Stirring of the above reaction mixture 1 was continued at room temperature for an additional 16 hours. The pressure bottle was then cooled in an i-PrOH/dry ice bath and rubber septum was removed. The reaction mixture was allowed to degas fully by stirring for several minutes open to the air at room temperature. Saturated aqueous NaHCO 3 was added to the reaction mixture 1, and the resultant reaction mixture was stirred for 2 hours at room temperature. The pH of the aqueous layer was measured and it was about 8. Addition of water removes an emulsion that sometimes formed in the neutralization. The aqueous layer was washed with DCM. The combined DCM extract was washed with saturated aqueous NaHCO 3 , water, and saturated aqueous NaCl solution. The organic layer was dried (MgSO 4 ) and filtered, on evaporation provided intermediate compound 2.
Step 2: The condensation of amino thiol with intermediate compound 2 in paraformaldehyde gave thiazolidine intermediate compound 3.
Step 3: Thiazolidine derivative intermediate compound 3 was treated with 1.0 equivalents of 1-chloroethylchloroformate in presence 1.5 equivalents of N,N-Diisopropylethylamine (DIPEA) in anhydrous Dimercaprol at 0° C. and the reaction mixture 2 was stirred for 30 min at 0° C. to yield intermediate compound 4.
Step 4: Intermediate compound 4 was added slowly to the solution of (2,2-dimethyl-1,3-dithiolan-4-yl)methanol sodium salt in dry dimethylformamide (DMF) at 0° C. to make reaction mixture 3. The reaction mixture 3 was stirred for 16 hour at room temperature. The reaction mixture 3 was dried using evaporation technique. The dried reaction mixture was divided and then washed with water and DCM. The combined organic layers were washed with brine solution, dried over anhydrous Na 2 SO 4 and then evaporated under reduced pressure. The resultant crude was purified by column chromatography over 100-200 mesh silica gel to yield compound 5.
Step 5: The final step is hydrolysis of tert-butyl ester, acetonide and thiazolidine group of intermediate compound 5. Intermediate compound 5 is treated with 25% TFA dissolved in DCM to produce final compound 6. In one embodiment, the Tert-butyl ester can be prepared using 1-ethyl-3-(3′-dimethylaminopropyl) carbodiimide (EDCI) coupling conditions. It may be prepared by reacting D-(−)-Pencillamine with t-butanol using EDCI coupling conditions. In another embodiment, first one may protect aminothiol of D-(−)-Penicillamine and then react with Boc anhydride and 4-(N,N-dimethylamino) pyridine (DMAP) dissolved in DCM. In another embodiment, the amino acid may be converted to tert-butlyester by reacting the amino acid with t-butanol, magnesium sulfate and sulfuric acid mixed with DCM.
[0072] Results for Synthesis 1:
[0073] Initial Compound 1:
(S)-2-amino-3-mercapto-3-methylbutanoic acid
[0074]
[0075] M.F: C5H11NO2S, Mol. Wt.: 149
[0000]
TABLE 1
CHN Analysis
Atom
Intensity
C
40.25
H
7.43
N
9.39
O
21.45
S
21.49
[0000]
TABLE 2
H NMR Analysis
δ
Protons
Group
1.46
6H
2XCH3
3.79
1H
CH
[0076] Intermediate Compound 2:
(S)-tert-butyl 2-amino-3-mercapto-3-methylbutanoate
[0077]
[0078] M.F: C9H19NO2S, Mol. Wt.: 205
[0000]
TABLE 3
CHN Analysis
Atom
Intensity
C
52.65
H
9.33
N
6.82
O
15.59
S
15.62
[0000]
TABLE 4
H NMR Analysis
δ
Protons
Group
1.40
9H
3XCH3 (tBu)
1.46
6H
2xCH3
3.75
1H
CH
[0079] Intermediate Compound 3:
(S)-tert-butyl 5,5-dimethylthiazolidine-4-carboxylate
[0080]
[0081] M.F: C10H19NO2S, Mol. Wt.: 217
[0000]
TABLE 5
CHN Analysis
Atom
Intensity
C
55.27
H
8.81
N
6.44
O
14.72
S
14.75
[0000]
TABLE 6
H NMR Analysis
δ
Protons
Group
1.40
9H
3XCH3 (tBu)
1.46
6H
2xCH3
3.65
2H
CH2
3.71
1H
CH
[0082] Intermediate Compound 5:
(4S)-3-(1-((2,2-dimethyl-1,3-dithiolan-4-yl)methoxy)ethyl) 4-tert-butyl 5,5-dimethylthiazolidine-3,4-dicarboxylate
[0083]
[0084] M.F: C19H33NO5S3, Mol. Wt.: 452
[0000]
TABLE 7
CHN Analysis
Atom
Intensity
C
50.53
H
7.36
N
3.10
O
17.71
S
21.30
[0000]
TABLE 8
H NMR Analysis
δ
Protons
Group
1.35
6H
2xCH 3
1.40
9H
3XCH 3 (tBu)
1.55
9H
3XCH 3
2.64-3.13
3H
SCH, SCH 2
3.83
2H
OCH 2
4.06-4.16
2H
SCH 2 N
4.68
1H
CHN
5.49
1H
OCHO
[0085] Final Compound 6:
[0000]
[0086] M.F: C11H21NO5S3, Mol. Wt.: 343
[0000]
TABLE 9
CHN Analysis
Atom
Intensity
C
38.46
H
6.16
N
4.08
O
23.29
S
28.01
[0000]
TABLE 10
H NMR Analysis
δ
Protons
Group
1.46
6H
2xCH 3
1.55
3H
CH 3
2.69-3.19
3H
SCH, SCH 2
4.76
1H
CHN
5.49
1H
OCHO
Example Synthesis 2
[0087] In synthesis 2, as shown in FIG. 2 , in this approach protection of aminothiol derivative 2 is different from earlier method of synthesis 1, i.e., Trityl group used instead of thiazolidine.
Example Synthesis 3
[0088] In synthesis 3, as shown in FIG. 3 , (1, 3-dithiolane-4-yl)methanol intermediate used instead of (2,2-dimethyl-1,3-dithiolan-4-yl)methanol at stage-4 as shown in FIG. 3 .
[0089] The present disclosure provides among other things compositions and methods for treating Copper toxicity related diseases and complications. While specific embodiments of the subject disclosure have been discussed, the above specification is illustrative and not restrictive. Many variations of the compounds, compositions and methods herein will become apparent to those skilled in the art upon review of this specification.
INDUSTRIAL APPLICABILITY
[0090] There are multiple applications for compound of formula 1, composition of formula 1 with pharmaceutically acceptable additives to treat mammals suffering from metal accumulation in blood and other organs, more specifically genetic and abnormal accumulation of metal in the liver in general. These compositions may be used in the treatment of diseases related to disorders related to metal accumulation in blood and other organs. | A compound, composition and method of making and using a compound of formula 1 are disclosed. The compound of formula I also comprises of salts, polymorphs, solvates, mesylates, hydrochloric salt, solvates and hydrates thereof. The compound may be formulated as pharmaceutical compositions. The pharmaceutical compositions may be formulated for peroral, topical, transmucosal, inhalation, targeted delivery and sustained release formulations. Such compositions may be used to treat metal accumulation in blood, organs and due to genetic complications. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a method for collecting oil, and particularly to a method for collecting oil with modified clay, which can be applied to oil pollution remedies or secondary oil recovery.
[0003] 2. Related Prior Arts
[0004] Off-shore drilling and sea transportation of crude oil bring about huge economic interest. However, oil pollutions including waste oil discharged from ships and leaking from pipes or oil rigs always result in environmental disasters.
[0005] To solve the above problems, chemical oil adsorbent or dispersants are usually applied and then accompanied with biological agents to degrade oil. However, these methods always cost very high and the procedures are complex.
[0006] The present invention therefore provides a simple method for collecting oil by effectively adsorbing oil with a relatively cheap adsorbent.
SUMMARY OF THE INVENTION
[0007] The object of the present invention is to provide a method for collecting oil.
[0008] To acheive the above object, the oil are mixed with a modified clay and then adsorbed by the modified clay. The modified clay is clay intercalated with a hydrophobic polymeric chemical. The clay can be layered silicate clay, mica or talc having a cation exchange capacity (CEC) ranging from 50 meq/100 g to 200 meq/100 g.
[0009] Natural inorganic clay is a rich resource on the earth and usually has a layered structure of silicate. Each silicate layer is about 1 nm thick and the interlayer space is about 12.4 Å. If surface properties of the silicate layers can be effectively modified to make the clay more compatible with organic molecules, the clay could be used for adsorbing oil.
[0010] The silicate clay also has a high aspective ratio (about 1×100×100 nm). By intercalating the clay with polymeric chemicals at different CEE (cation exchange equivalent) ratio, the interlayer space of the clay can be increased. The modified clay then becomes hydrophobic and has a larger density of the layer space so that the oil can be effectively adsorbed therein.
[0011] The above polymeric chemical can be acidified poly(oxyalkylene)-amine, wherein the oxyalkylene segments can be one or both of hydrophobic oxypropylene (PO-) segments and hydrophilic oxyethylene (EO-) segments. After being acidified, poly(oxyalkylene)-amine is transformed into a quaternary ammonium salt and both of the PO-segments and EO-segments are water soluble and compatible with silicate clay.
[0012] In the present invention, the poly(oxyalkylene)-amine usually has a molecular weight ranging from 50 g/mol to 10,000 g/mol, preferably from 400 to 5,000 g/mol, and more preferably from 1,000 g/mol to 4,000 g/mol. Poly(oxyalkylene)-amine preferably has an segment ratio (EO/PO) ranging from 0 to 0.1, and the number of PO-segments is preferably from 13 to 80. Examples of poly(oxyalkylene)-amine include poly(oxyethylene)-monoamine, poly(oxypropylene)-monoamine, poly(oxyethylenepropylene)-monoamine, poly(oxyethylene)-diamine, poly(oxypropylene)-diamine, poly(oxyethylenepropylene)-diamine, poly(oxyethylene)-triamine, poly(oxypropylene)-triamine, and poly(oxyethylenepropylene)-triamine.
[0013] In the present invention, the oil can be crude oil, oily drug or other oily materials and the clay is preferably montmorillonite. The modified clay preferably has an interlayer space ranging from 28 Å to 92 Å.
[0014] The CEE ratio of poly(oxyalkylene)-amine to the modified clay is preferably ranging from 0.25 to 1.0, and more preferably from 0.3 to 0.6.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1A shows the structure of Na + -montmorillonite (Na + -MMT).
[0016] FIG. 1B shows the structure of Na + -montmorillonite (Na + -MMT).
[0017] FIG. 1C shows the structure of Na + -montmorillonite (Na + -MMT).
[0018] FIG. 2 shows the layered clay modified with poly(oxyalkylene)-diamine.
[0019] FIG. 3 shows the LCAT (Lower Critical Aggregation Temperature) ranges of Examples 1.6, 2.5 and Comparative Example 1.3.
ATTACHMENTS
[0020] ATTACHMENT 1 shows the weight ratios of crude oil/adsorbent obtained in the Examples.
[0021] ATTACHMENT 2 shows three samples having different effects of adsorbing crude oil.
[0022] ATTACHMENT 3 shows the ranges of the saturated adsorption ratios obtained in the Examples.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] The materials used in the preferred embodiments of the present invention include:
[0024] 1. Na + -montmorillonite: Na + -MMT, having cation exchange capacity (CEC) of about 1.2 meq/g, product of Nanocor Ind. Co.
[0025] 2. Poly(oxyalkylene)-amine of JEFFAMINE® series: Products of Huntsman, as shown in FIG. 1A , FIG. 1B , FIG. 1C , for example, D-2000, D-4000, M-2070 and M-2005.
[0026] 3. Poly(oxyalkylene)-amine of SURFONAMINE® series: Products of Huntsman, for example, B-100 (a hydrophobic monoamine, a PO-derivative chemical of nonylphenol, having a molecular weight of about 1,000).
[0027] 4. Crude oil: Purchased from CPC Corporation, Taiwan.
Example 1.1
1. Intercalating of Clay
[0028] (a) MMT (5 g) was dispersed and swollen in deionized water (500 g) at 80° C. for three hours to prepare a stable and uniform dispersion.
[0029] (b) D-2000 (3 g) was added to deionized water (10 g) and then acidified with HCl (35 wt %; 0.16 g).
[0030] (c) The acidified D-2000 was added into the MMT dispersion to perform intercalation by continuously mixing at 80° C. for five hours. FIG. 2 shows the layered clay modified with poly(oxyalkylene)-diamine.
[0031] (d) After the reaction was completed, the intercalated clay (D-2000/MMT) was collected through filtration to serve as an adsorbent of crude oil. The cation exchange equivalent (CEE) ratio of D-2000/MMT was 0.25. The CEE ratio was determined as follows:
[0000] CEC(MMT)=1.2 meq/g
[0000] CEC( D -2000)=0.5 meq/g
[0000] CEE ratio of D -2000/MMT=(3 g×0.5 meq/g)/(5 g×1.2 meq/g)=0.25
2. Adsorbing Crude Oil
[0032] (e) D-2000/MMT (2.5 g) was dissolved in water at 5° C. to give a D-2000/MMT dispersion (2 wt %) as D-2000/MMT has a property of lower critical solubility temperature (LCST).
[0033] (f) The D-2000/MMT dispersion (25 g) was placed in a 100 ml beaker with a magnetic stirrer, and then crude oil was dropped therein with stirring at low temperature. The weight ratio of crude oil/adsorbent was shown in ATTACHMENT 1 .
[0034] (g) The mixture was stirred in an ice bath for 30 minutes.
[0035] (h) The mixture was further stirred at room temperature for 30 minutes and then allowed to settle. The crude oil adsorbed by the clay was measured. ATTACHMENT 2 showed three typical statuses for judging the effects of adsorbing crude oil. Picture ( 1 ) indicated good performance as no crude oil adhered on the bottle wall after shaking the sample. Picture ( 2 ) indicated poor performance as the crude oil adhered on the bottle wall and could not be separated therefrom after shaking the sample. Picture ( 3 ) also indicated poor performance as excess crude oil resulted in adhering of the crude oil to the bottle water.
Examples 1.2-1.5
[0036] The steps of Example 1.1 were repeated, except that in step (b), 5 g of D-2000 was added and 0.25 g of HCl was used for acidification. As a result, the CEE ratio of the adsorbent (D-2000/MMT) was 0.42. In step (f), crude oil was added according to the weight ratios of crude oil/adsorbent listed in ATTACHMENT 1 .
Example 1.6
[0037] The steps of Example 1.1 were repeated, except that in step (b), 6 g of D-2000 was added and 0.625 g of HCl was used for acidification. As a result, the CEE ratio of the adsorbent (D-2000/MMT) was 1.0. In step (f), crude oil was added according to the weight ratio of crude oil/adsorbent listed in ATTACHMENT 1 .
Examples 2.1-2.5
[0038] The steps of Example 1.1 were repeated, except that in step (b), D-2000 was replaced with D-4000, and the amounts thereof added were 24 g, 10 g, 10 g, 10 g and 6 g, respectively, and the amounts of HCl used were 0.625 g, 0.25 g, 0.25 g, 0.25 g and 0.16 g, respectively. Then CEE ratios of the adsorbent D-4000/MMT were respectively 1.0, 0.42, 0.42, 0.42 and 0.25. In step (f), crude oil was added according to the weight ratios of crude oil/adsorbent listed in ATTACHMENT 1 .
Examples 3.1-3.4
[0039] The steps of Example 1.1 were repeated, except that in step (b), D-2000 was replaced with B-100, and the amounts thereof added were 6.0 g, 6.0 g, 2.5 g and 2.5 g, respectively, and the amounts of HCl used were 0.625 g, 0.625 g, 0.25 g and 0.25 g, respectively. Then CEE ratios of the adsorbent B-100/MMT were respectively 1.0, 1.0, 0.42 and 0.42. In step (f), crude oil was added according to the weight ratios of crude oil/adsorbent listed in ATTACHMENT 1 .
Comparative Examples 1.1-1.3
[0040] The steps of Example 1.1 were repeated, except that in step (b), D-2000 was replaced with M-2005, and the amounts thereof added were 12 g, 12 g and 5 g, respectively, and the amounts of HCl used were 0.625 g, 0.625 g and 0.25 g, respectively. Then CEE ratios of the adsorbent M-2005/MMT were respectively 1.0, 1.0 and 0.42. In step (f), crude oil was added according to the weight ratios of crude oil/adsorbent listed in ATTACHMENT 1 .
Comparative Example 2
[0041] The steps of Example 1.1 were repeated, except that in step (b), D-2000 was replaced with M-2070, and the amount thereof added was 12 g, and the amount of HCl used was 0.625 g. Then CEE ratio of the adsorbent M-2070/MMT was 1.0. In step (f), crude oil was added according to the weight ratio of crude oil/adsorbent listed in ATTACHMENT 1 .
Comparative Example 3
[0042] The steps of Example 1.1 were repeated, except that step (b) was skipped to use MMT as the adsorbent. In step (f), crude oil was added according to the weight ratio of crude oil/adsorbent listed in ATTACHMENT 1 .
[0043] ATTACHMENT 1 also shows the effects of the above Examples and Comparative Examples.
[0044] For Comparative Example 2, M-2070/MMT did not perform as well as Examples. The reason was that M-2070 was hydrophilic and could not transform the hydrophilic clay into hydrophobic clay, so that the polymers between the layers could not effectively provide a hydrophobic phase to adsorb crude oil into the layers. As a result, the crude oil dispersed in water and could not be aggregated.
[0045] For Comparative Example 3, unmodified MMT was hydrophilic clay and could adsorb crude oil on surfaces thereof but could not effectively attract the crude oil into the layers of clay. Therefore, its effect was not good, either.
[0046] For Comparative Example 1.3, though M-2005/MMT (1.0 CEC) was hydrophobic, the adsorption effect thereof was not good. The reason was that M-2005/MMT had a LCAT (Lower Critical Aggregation Temperature) around room temperature. That is, at about 25° C., with similar ratios of organic/inorganic, M-2005/MMT (1.0 CEE) could not adsorb crude oil as well as D-2000/MMT (1.0 CEC). FIG. 3 showed the ranges of LCAT for Examples 1.6 and 2.5 and Comparative Example 1.3.
[0047] For D-2000/MMT (0.25 CEC), crude oil was not effectively adsorbed when the weight ratio of crude oil/MMT was 9. The reason was that the polymers between layers did not provide enough hydrophobicity at such CEE ratio. B-100/MMT (0.42 CEC) was the same.
[0048] ATTACHMENT 3 shows the saturated adsorption ratio of the adsorbents to oil.
Influence of Interlayer Space of the Modified Clay on Adsorption
[0049] As micelles, the modified clay could gather with each other to become a larger mass. Within the mass, the crude oil was not only attracted between the clay layers but also embedded by the clay.
[0050] To understand the mechanism of adsorption of crude oil by clay at different CEE ratios, the modified clay (D-2000/MMT, the weight ratio of crude oil/modified clay=4/1) was exemplified as follows:
[0051] (1) For 0 CEE (unmodified clay), crude oil could not be adsorbed at all.
[0052] (2) For 0.25 CEE (polymer/clay), crude oil could not be effectively adsorbed as there was not enough hydrophobic polymer in the clay.
[0053] (3) For 0.42 CEE (polymer/clay), the clay was hydrophobic enough to effectively adsorb crude oil into the layers thereof and oil was embedded within the clay; i.e., the effect was the best.
[0054] (4) For 1.0 CEE (polymer/clay), too much polymer between the layers of clay (i.e., the density of the layer space increased) so that crude oil could not easily enter into the layer space to be effectively embedded, but was adsorbed only on the surfaces of the clay. The effect was therefore not as good as when CEE is 0.42.
[0055] For the modified clay (D-2000/MMT, 0.42 CEE) at room temperature, crude oil was added in different weight ratio of crude oil/modified clay at 4, 6, 10 and 12. When more crude oil was adsorbed and embedded by the modified clay, the integral density would decrease. Therefore, the mixture of oil and the modified clay gradually floated up from the bottom.
[0056] In addition, compared to D-4000/MMT (0.25 CEE) with an interlayer space of 17 Å, D-2000/MMT (0.42 CEE) with an interlayer space of 45 Å performed better because of its larger space for accommodating or holding more oil though they were similar in organic contents and hydrophobicity.
Dispersing Ability of the Modified Clay at Low Temperature
[0057] B-100/MMT (1.0 CEE) and D-2000/MMT (0.42 CEE) were similar in organic contents, hydrophobicity and interlayer spaces. However, D-2000/MMT performed better because it could be better dispersed at low temperature.
[0058] The present invention provides a method for recovering oil more effectively than the traditional methods. For example, the weight ratio (crude oil/MMT) could reach up to 20 when D-2000/MMT (0.42 CEE) was applied. Moreover, the mixture of oil and clay could be easily removed from seas after its use. | The present invention provides a method for collecting oil with a modified clay. By mixing the modified clay and oil, the oil can be adsorbed to the clay. The modified clay is obtained by intercalating a hydrophobic polymer such as acidified poly(oxyalkylene)-amine into layered silicate clay, mica or talc to enlarge the interlayer space. The modified clay thus becomes hydrophobic and adsorption to the oil is promoted. | 1 |
BACKGROUND OF THE INVENTION
2. FIELD OF THE INVENTION
This invention relates to a method of preparing very low pour point oils suitable for use as transformer oils. More particularly, this invention relates to an improved process for producing low pour point transformer oils from paraffinic crudes.
2. DESCRIPTION OF THE PRIOR ART
Transformer oils are known in the prior art as high stability electrical insulating oils and are also used in other electrical equipment such as circuit breakers. In addition to possessing relatively low viscosity, high dielectric strength and a relatively high flash point, these oils are further characterized in that they must have a relatively low pour point. This is particularly necessary where the oils are to be used in colder climates. Additionally, these oils must be low in corrosive agents such as acid, alkali and sulfur and resistant to oxidation and sludge formation.
Several methods for preparing insulating oils are known in the prior art. In general, they are produced from wax-free naphthenic crude oils which are not native to many parts of the world and consequently command premium prices and involve high transportation costs. Although these crudes permit production of exceptionally low pour point insulating oils without the need for dewaxing or special attention to the degree of fractionation or distillate cut width, they also contain high percentages of sulfur and nitrogen which must be removed in order to satisfy the stringent stability requirements of insulating oils.
Extremely stable insulating oils produced either totally or partially from paraffinic crudes by conventional dewaxing techniques are also used in certain applications where moderate climatic conditions do not demand oils with especially low cloud or pour points. When exceptionally low pour points are required, however, deep dewaxing of paraffinic distillates at temperatures below -40° F cannot compete economically with the manufacture of these oils from naphthenic crudes.
A process which avoids deep dewaxing and produces competitively priced, low viscosity oils with exceptionally low pour points from paraffinic distillates was disclosed in U.S. Pat. No. 2,906,688. In this process a broad, wax-containing fraction is first sharply fractionated to yield a narrow heart cut of suitable viscosity which is then dewaxed at about 0° F to yield a dewaxed oil having a pour point of -50° F, or lower. The narrow cut also may be solvent extracted prior to dewaxing without materially affecting the pour point of the product. The difficulty associated with this process is related to the nature of the low pour point oils produced. Although they have low pour points, their cloud points, which mark the onset of wax precipitation, are relatively high, approximating the dewaxing temperature used in making them. This, in turn, makes the pour point of the product extremely sensitive to waxy contaminants such as paraffin wax, which would certainly be encountered in process lines comprising solvent treating (extraction), hydrofining and dewaxing units which normally operate on relatively high pour point, wax-bearing streams. In fact, it has been found that the addition of as little as 0.5 percent of a paraffin wax to an insulating oil prepared by the aforedescribed process and having a cloud point of -12° F will raise the pour point from -50° F to -5° F, whereas the addition of the same amount of paraffin wax to a wax-free, naphthenic oil having the same viscosity and pour point does not affect the pour point at all.
U.S. Pat. No. 3,627,673 discloses a process for producing low pour point transformer oils from paraffinic crudes which eliminates the highly specialized fractionating tower needed for the initial narrow cut distillate required in U.S. Pat. No. 2,906,688 as well as avoiding the waxy contaminant sensitivity of the product produced by said process. The U.S. Pat. No. 3,627,673 process comprises taking a narrow cut having a 5 to 95 LV (liquid volume) % boiling range between 550° to 750° F from a conventional crude oil vacuum pipe still, solvent extracting, dewaxing and hydrofining the dewaxed raffinate, followed by fractionally distilling the hydrofined dewaxed raffinate to obtain a narrow cut (heart cut) having a 5/95 LV% boiling range of from 580° to 720° F or narrower. However, the fractionating or rerun column required in this process is rather complex and contains a relatively large number of plates therein.
It would be a great improvement to the art if one could obtain low pour point transformer oils from paraffinic crudes without encountering the waxy contaminant sensitivity of the product produced by the process in U.S. Pat. No.2,906,688 and at the same time avoid the necessity of the special fractionating columns required in both the U.S. Pat. Nos. 2,906,688 and 3,627,673 processes.
BRIEF SUMMARY OF THE INVENTION
In accordance with the present invention, a low pour point transformer oil is efficiently and conveniently produced by a process which comprises
1. solvent extracting a waxy distillate fraction of a paraffinic crude, said fraction having a 5 to 95% boiling range of 595° to 755° F at atmospheric pressure to produce an extract and a raffinate;
2. solvent dewaxing said raffinate at a temperature of from about -10° to -40° F under liquid-liquid immiscible conditions to form a three phase slurry containing a solid waxy phase, an oil-rich liquid phase and a solvent-rich liquid phase;
3. filtering said slurry at a temperature of from about -10° to about -40° F to form a filtrate substantially comprising the solvent-rich phase and a wax cake containing most of the oil-rich phase; and
4. recovering a low pour point transformer oil from the filtrate.
The waxy distillate fraction derived from the paraffinic crude may be obtained, as a narrow cut having a 5 to 95% boiling range of from about 595° to 755° F, from a conventional crude oil vacuum pipe still. This distillate is solvent extracted to remove a substantial portion of the aromatic and polar constituents therefrom using conventional extraction solvents such as NMP, phenol, furfural, etc. The dewaxing solvent composition is adjusted so that a three phase slurry is formed from the extracted distillate or raffinate in the dewaxing zone, comprising a solid waxy phase and two immiscible liquid phases, with the low pour point transformer oil being one of the constituents of the solvent-rich liquid phase. Generally, the dewaxing temperature should not be higher than -20° F and the cold slurry is then filtered at about the dewaxing temperature. During the filtration operation, the oil-rich liquid phase behaves like wax and remains on the filter with the wax cake. However, the solvent-rich phase containing the transformer oil passes through the filter as filtrate and the transformer oil is recovered therefrom.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow diagram of a process for producing low pour point transformer oils in accordance with one embodiment of this invention.
FIG. 2 is a graph illustrating the solubility of a paraffinic oil in mixed ketone solvents.
DETAILED DESCRIPTION
Referring to FIG. 1, a wax-containing paraffinic crude, such as an Aramco crude, is fed into a conventional refinery crude still 10 via line 1, wherein the crude oil is fractionated into several cuts, including a cut having a 5 to 95 LV% boiling range of 595° to 755° F, as measured at atmospheric pressure, which contains the desired transformer oil. The cut containing the transformer oil is taken from the vacuum portion of the crude still 10 through line 2, and transferred to extraction unit 11 wherein the aromatic and polar constituents of the transformer oil fraction are reduced by solvent extraction using conventional extraction solvents such as phenol, furfural, NMP, etc. The extraction solvent enters extraction unit 11 via line 3 wherein it contact the transformer oil cut, the flow of the solvent being preferably countercurrent to the flow of the oil. An extract phase and a raffinate phase are formed in the extraction unit. A substantial portion of the extraction solvent leaves extraction unit 11 via line 4 as a major component of the extract phase which comprises most of the solvent and most of the aromatic and polar constituents of the transformer oil fraction. The raffinate phase containing the desired transformer oil fraction passes overhead thru line 5 to dewaxing unit 12. Cold dewaxing solvent such as a mixture of MEK/MIBK enters dewaxing unit 12 via line 6 and is admixed with the raffinate therein. The wax content of the raffinate is reduced to the desired level by cooling the solvent/raffinate mixture to a predetermined temperature, such as -25° F, thereby precipitating the wax out of the raffinate. Both the temperature and composition of the dewaxing solvent are adjusted (i.e., 90/10 LV% MEK/MIBK and -25° F) so as to form a slurry having two liquid phases and one solid waxy phase at the end of the chilling cycle in dewaxer 12. Dewaxer 12 may also comprise one or more scraped surface chillers for further cooling the solvent/raffinate mixture in order to achieve the three phase slurry, if desired. The solid phase comprises the wax while the two liquid phases comprise an oil-rich phase and solvent-rich phase, the latter containing the desirable low pour point (below -40° F) transformer oil. The slurry is passed from the dewaxer 12 to filter 13 via line 7 where the solvent-rich liquid phase is removed as a filtrate thru line 9 and from there sent to means such as solvent strippers (not shown) for separating solvent from the desired low pour point transformer oil. The oil-rich liquid phase behaves like wax during filtration and becomes part of the filter cake which is removed from filter 13 via line 8. The wax cake containing the oil-rich phase is then further processed by any suitable means to separate the high viscosity index oil from the wax. For example, a second stage of miscible filtration can be employed to recover the high viscosity index oil left in the wax cake from the first filter. The second filter can be run under miscible conditions by either increasing the filter temperature towards the miscibility point or by adding further dewaxing solvent (richer in MIBK) to the wax cake so as to raise its solvent to oil ratio and MIBK content. The resulting filtrate and wax cake are sent to solvent recovery so that the recovered high viscosity index oil (from filtrate) and wax can be further refined.
The recovered lube oil products may, if so desired, be subjected to various finishing operations such as clay contacting, hydrofining, acid treatment and the like. In addition, various inhibitors and other additive ingredients may be added in order to provide finished lube oil products.
By the method of the present invention, a high stability, low pour point transformer oil may be obtained from a waxy, paraffinic crude oil such as are obtained from Western Canada, Saudi Arabia, Kuwait, the Panhandle, Tia Juana, etc. By a low pour point is meant at least below -40° F and preferably about -50° F or lower.
The transformer oil fraction employed in the instant invention is generally derived from the waxy, paraffinic crude by a crude oil vacuum pipe still.
However, it is essential to the practice of this invention that the transformer oil fraction taken from the vacuum portion of the crude distillation unit be a relatively narrow cut, low viscosity, paraffinic oil distillate with a viscosity of about 40 to 70 SUS at 100° F, and more preferably about 45 to 65 SUS at 100° F, and most preferably 50 to 60 SUS at 100° F. By narrow cut is meant a cut having a 5 to 95% boiling range of between 595 to 755° F at a pressure of one atmosphere. This cut will contain the low pour point transformer oil fraction sought to be recovered in the present invention. More preferred are fractions exhibiting a boiling range of from about 600 to 750° F and most preferably 600 to 735° F at 1 atmosphere pressure.
These well fractionated, narrow cut, low viscosity distillates are desirable, because when ketone dewaxed (i.e., at -10° F) they exhibit a pour-filter inversion phenomenon in which the pour point of the dewaxed oil can be as low as 30° to 40° F below the dewaxing temperature, in contrast to conventional (broad cut) distillates wherein the pour point is generally about 5° above the dewaxing temperature. This invention refers to narrow cut fractions described above which can be taken from a conventional crude oil vacuum distillation tower. These narrow cut fractions are not narrow enough to give the desired 30° to 40° F pour-filter inversions without further treatment. An additional pour point decrease of 10° F or more below the dewaxing temperature is achieved by the extraction-immiscible dewaxing-filtration steps of the instant invention. Finally, it is important that the transformer oil fraction be obtained as a heart cut from the vacuum crude distillation unit and having a 5 to 95 LV% boiling range of between 595° to 755° F at atmospheric pressure. In general, material boiling in this range will exhibit a pour-filter inversion effect and will contain the desired transformer oil fraction, which most preferably will have a viscosity of from 50 to 60 SUS at 100° F, but which may have a viscosity outside of these limits, depending on the application desired for the oil.
The undesirable aromatic and polar constituents of the transformer oil fraction are removed by contacting or extracting the oil with solvents having an affinity for such compounds. These solvents are well known in the art and include phenol, N-methyl-2-pyrollidone, furfural, NMP/phenol and the like along with up to about 20% of water. The water is employed in the extraction solvent in order to increase the selectivity of same for the aromatic and polar constituents of the oil. Generally, about 1/2 to 4 volumes of solvent per volume of oil are used in the solvent extraction step. The temperature used is generally in the range of from 120° to 250° F at pressures in the range of about atmospheric up to about 250 psig. In general, the solvent flows downwardly in a vertical extraction tower and counter-currently contacts the up-flowing oil under conditions wherein the more aromatic and polar-type constituents are dissolved in the solvent forming an oil-rich raffinate phase and a solvent-rich extract phase. The downwardly flowing extraction solvent may contain the desired amount of water or, alternatively, the water may be separately injected near the bottom of the extraction unit. The extract phase is removed from the extraction zone and is processed to segregate the solvent from the aromatic and polar-type compounds, with the solvent being recycled either to the extracting zone or to solvent storage. In general, if solvents such as phenol and furfural are used for the extraction, then any solvent which may be entrained in the raffinate phase is removed from said phase prior to the dewaxing operation. However, if N-methyl-2-pyrrolidone is used as the extraction solvent it may not be necessary to remove any solvent entrained in the raffinate phase prior to the dewaxing operation. It is the raffinate from the extraction operation that contains the desired transformer oil fraction.
The raffinate from the extraction is solvent dewaxed using any dewaxing solvents that will form the desired three-phase slurry. It is critical to the instant invention that a three-phase slurry is ultimately fed to the wax filters subsequent to the dewaxing step. For example, the raffinate may be contacted with an autorefrigerative/ketone dewaxing solvent such as propane/MIBK/acetone, propylene/MIBK/acetone, propylene/MEK/MIBK, propylene/MEK/toluene and the like, with the resulting mixture cooled to achieve liquid-liquid immiscibility and precipitation of the wax at least partially by in situ autorefrigerative means. Another dewaxing solvent comprises mixtures of ketones having 3 to 6 carbon atoms with each other or with single ring aromatic solvents such as MEK/toluene. Particularly preferred solvents that have been found useful for producing the desired three-phase, liquid-liquid-solid slurry wherein the solid comprises wax and one of the liquid phases is solvent-rich and contains the desired transformer oil, include the binary mixtures MEK/MIBK and acetone/MIBK.
Parameters controlling formation of the three-phase slurry required to achieve the desired pour point reduction include (1) solvent composition, (2) temperature, (3) oil feed and (4) solvent/oil ratio. The interrelation of these parameters for a Light Arabian raffinate at a solvent/feed ratio of 2/1, using MEK/MIBK as the dewaxing solvent, is illustrated in FIG. 2. In general, the MEK in the MEK/MIBK solvent will range from about 45 to about 95 LV% at filtration temperatures of from about -10° F to -40° F. To ensure immiscibility at filtration temperatures ranging between -10° F to -40° F when using the acetone/MIBK binary mixture, the latter's composition should range between 55 to 95 LV% acetone, preferably between 50 to 75 LV% acetone.
The solvent is normally prechilled before it is mixed with the waxy oil (transformer oil fraction). It is possible to achieve immiscibility and at the same time bring the temperature of the slurry down to the filtration temperature solely by means of injecting cold solvent into the waxy oil. However, more often the waxy oil is partially cooled by mixing same with a cold dewaxing solvent, with additional cooling taking place by other means such as passing the wax/oil/solvent mixture through scraped surface exchangers, etc. which may also be considered as comprising part of the dewaxer. That is, mixing of the oil and solvent may take place under miscible conditions with a single phase resulting, wax precipitation and liquid-liquid immiscibility being achieved by further cooling the final mixture down to the appropriate temperature. It is to be understood of course that the appropriate solvent choice as well as the ultimate temperature to which the mixture and slurry is eventually cooled will depend upon a number of factors such as the nature and composition of the solvent, feed, desired pour point, etc. In general, the temperature to which the slurry is ultimately cooled prior to filtration will be between - 10° and -40° F, the preferred temperature being between -15° and -35° F and most preferred -20° and -30° F. The temperature of the slurry as it is being filtered will be that temperature reached prior to filtration, supra. The pour point of the transformer oil product will depend on the feed, dewaxing temperature, solvent, dilution ratio, etc., as hereinbefore described, supra.
The recovered dewaxed oil products may be hydrofined to improve color, oxidation stability and reduce sulfur content. This may be accomplished by contacting the dewaxed oil with a suitable hydrofining catalyst containing the sulfides or oxides of combinations of metals such as cobalt and molybdenum, nickel and molybdenum, nickel and tungsten, etc. In general, hydrofining is accomplished by passing the dewaxed oil over a fixed bed at a space velocity of between 0.3 and 3.0/V/V/Hr. at a temperature between 350° and 650° F and under a hydrogen partial pressure of between 300 and 900 psig. However, this step is not essential for the purposes of this invention and may be omitted.
DESCRIPTION OF A PREFERRED EMBODIMENT
This invention will be more apparent from the preferred embodiment which is illustrated by the following example.
EXAMPLE
Referring to FIG. 1, an Aramco crude was fed thru line 1 to a conventional refinery crude distillation unit 10. A waxy distillate fraction comprising 5.4 LV% of the crude and having a 5 to 95% boiling range of 602 to 737° F (ASTM D-2887-70T), a pour point of +47° F and a viscosity of 56 SUS at 100° F was recovered from the vacuum portion of the crude distillation unit thru line 2 and fed to extraction unit 11. The aromatic and polar constituents were removed from the distillate by contacting same with phenol entering extraction unit 11 via line 3. The volume treat ratio of phenol (containing 8 volume % water) to the distillate fraction was 131 LV%. Twenty-nine LV% of the distillate fraction was removed from the extraction unit as an extract phase via line 4. The remaining 71 LV% raffinate phase was fed to dewaxing unit 12 via line 5. The raffinate was mixed with cold MEK/MIBK dewaxing solvent entering unit 12 via line 6 to a final solvent/oil ratio of 2/1 by weight and a final temperature of -25° F, which resulted in precipitating a substantial amount of wax (19.5 weight %) from the oil. The slurry was then fed to wax filter 13 via line 7 wherein the precipitated wax was separated from the slurry by conventional vacuum filtration. The filter cake and filtrate were recovered via lines 8 and 9, respectively, and the solvent subsequently removed from the filtrate by distillation.
Dewaxing experiments were carried out using MEK/MIBK compositions of 50/50 LV%, 75/25 LV% and 90/10 LV% as shown in Table 1. Immiscibility was achieved by increasing the MEK content of the solvent past 85%, which is approximately the point at which the raffinate is just miscible with the MEK/MIBK mixture at -25° F. Miscibility data is shown in Table 1 and in FIG. 2.
The data in Table 1 show that immiscible liquid-liquid dewaxing yielded a 10° F pour point bonus in that the pour point of the immiscibly dewaxed product was -50° F, as compared to the pour point of -40° F achieved when the raffinate was dewaxed under miscible conditions. The data also illustrate the pour inversion obtained by extracting and then dewaxing the narrow fraction distillate feed of the instant invention, as evidenced by the pour points of the recovered transformer oils being considerably lower than the dewaxing temperature.
TABLE 1______________________________________TRANSFORMER OILS FROM PARAFFINIC CRUDESolvent MEK/MIBKComposition, LV% 50/50 75/25 90/10Solvent/Feed, w/w -- 2.0/1 --Filter Temperature, ° F -- -25 --° F from Immiscibility* +28(M) +4(M) -7(I) (M = Miscible; I = Immiscible)Low Pour Point Transformer Oil**Viscosity, SUS AT 100° F 56.0 56.2 56.7 210° F 34.2 34.3 34.3 Cloud Point, ° F -23 -27 -29 Pour Point, ° F -40 -40 -50______________________________________ *See FIG. 2. Just miscible with 85/15 LV% MEK/MIBK at -25° F. **No attempt was made to recover the oil-rich phase from the filter cake. | A very low pour point transformer oil is produced by a process wherein a narrow cut distillate of a paraffinic crude from conventional crude oil atmospheric or vacuum towers is first solvent extracted to remove aromatics and polar components, followed by immiscible solvent dewaxing whereby two liquid and one solid phases form a wax-containing slurry which is filtered to produce a wax cake which contains a high viscosity index oil and a filtrate which contains a very low pour point transformer oil. | 2 |
BACKGROUND OF THE PRIOR ART
Vinyl acetate-ethylene emulsions have been widely used as binders for, inter alia, paints, adhesives, and as binders for nonwoven and woven goods. The vinyl acetate-ethylene emulsions used for nonwoven goods generally contain a crosslinkable monomer, the crosslinking function being exercised after the emulsion is applied to a loosely assembled web of fibers. The crosslinking function serves to improve wet strength, dry strength, and solvent resistance in the goods.
Representative patents relating to vinyl acetate-ethylene emulsions and their use in various applications include:
U.S. Pat. No. 3,380,851 discloses a process for producing nonwoven fabrics by bonding together a loosely assembled web of fibers with the binder comprising an interpolymer of vinyl acetate-ethylene-N-methylol acrylamide where the interpolymer contains from 5 to 40% by weight ethylene and from 0.5 to 10% N-methlylol acrylamide by weight of the vinyl acetate. The emulsion is prepared by first forming a polymerization recipe of vinyl acetate, water, nonionic surfactant, reducing agent and, optionally, hydroxyethyl cellulose. The polymerization recipe is heated to a temperature of 50° C. although broadly 0° to 80° C. and pressurized with ethylene to an operating pressure ranging from about 10 to 100 atmospheres with sufficient time being permitted for the ethylene to saturate the vinyl acetate. At that time the recipe is initiated by addition of oxidizing agent (catalyst) and polymerization effected until the vinyl acetate concentration falls below about 1% generally 0.5% by weight of the emulsion. N-methylol acrylamide is added incrementally to the reactor during polymerization, and it generally takes approximately 4-5 hours for such addition.
U.S. Pat. No. 3,498,875 discloses a process for producing bonded nonwoven fabrics in a manner similar to the '851 patent except that the interpolymer comprises vinyl acetate, ethylene and a crosslinkable monomer of glycidyl acrylate. The polymerization process is essentially the same as the '851 patent wherein the vinyl acetate and ethylene are initially charged to the reactor and the glycidyl acrylate added incrementally during the polymerization. Normally such addition is completed in about 2 hours or within 40 to 50% of the totally polymerization time.
U.S. Pat. No. 3,137,589 discloses a process for producing bonded fiber fleeces by using a binder consisting of a thermoplastic polyvinyl compound incorporating a crosslinkable monomer. The particular monomer used for effecting the crosslinking function is an N-methylol amide of acrylic acid or methacrylic acid or maleic acid. By and large the copolymers are acrylic type copolymers e.g. a mixture of butyl and methylmethacrylate and N-methylol acrylamide.
U.S. Pat. No. 3,081,197 discloses a process for producing nonwoven fabrics bonded with an interpolymer of vinyl acetate, 0.3 to 12% crosslinkable monomer, e.g., N-methylol acrylamide, glycidyl acrylate, glycidyl methacrylate or allyl glycidyl ether and an internal plasticizer of vinyl pelargonate or polyethylene glycol methacrylate and so forth. It is reported that the nonwoven fabrics have good wet strength and dry strength as well as water absorbency.
U.S. Pat. No. 3,708,388 discloses vinyl acetate-ethylene copolymer latexes having particular adaptability for lamination. The vinyl acetate-ethylene emulsion optionally incorporates a crosslinking monomer of the post reactive type and these include glycidyl vinyl ether, glycidyl methacrylate, N-methylol acrylamide. The process set forth in '388 patent is essentially the same as that in the '851 reference.
U.S. Pat. No. 3,844,990 relates to a paint composition comprising a vinyl acetate-ethylene copolymer latex having a cellulosic thickener. The vinyl acetate-ethylene copolymer latex contains from about 5 to 40% ethylene and is prepared in essentially the same manner in the '851 vinyl acetate-ethylene emulsions. The basic difference is that no crosslinkable monomer is employed.
U.S. Pat. No. 3,770,680 discloses a process for producing a grit free aqueous polymer emulsion particularly suited as a base for wood adhesive, the polymer comprising reaction product of vinyl acetate, N-methylol acrylamide and acrylic acid.
U.S. Pat. No. 3,404,113 discloses a process for producing an aqueous paint composition comprising a vinyl acetate-ethylene-triallyl cyanurate polymer latex where the ethylene concentration is from 5 to 40% and the triallyl cyanurate is incorporated in an amount from about 0.5-10%. The triallyl cyanurate can be added incrementally or added to the batch prior to initiation. Again, the polymerization procedure is much like that procedure described in the '851 patent.
U.S. Pat. No. 3,288,740 discloses a process for producing aqueous emulsions containing interpolymer having a crosslinkable function e.g. an N-methylol function. Generally the copolymers comprise a lower alkyl ester of acrylic or methacrylic acid in combination with N-methylol acrylamide or the ethers of N-methylol acrylamide.
British Pat. No. 991,550 discloses a process for producing emulsions of vinyl acetate and ethylene. A polymerization is carried out at a temperature of from about 50° to 70° C. at pressures from 10 to 100 atmospheres generally 20 to 60 atmospheres. The process for preparing emulsions differs generally from that of the '851 patent in that the vinyl acetate is added continuously during the reation period rather than being added initially to the recipe. The delayed addition of vinyl acetate permits greater incorporation of ethylene into the polymer.
The inventors are also aware of a process to produce vinyl acetate-ethylene adhesive emulsions having a Tg of about 15°-19° C. One initiates polymerization of a recipe of vinyl acetate, ethylene, water, stabilizer and reducing agent at a temperature of 25° C. and a pressure below the operating pressure. The heat of reaction is utilized to achieve the operating temperature and operating pressure.
SUMMARY OF THE INVENTION
This invention relates to an improvement in a process for producing vinyl acetate-ethylene emulsions particularly adapted for the preparation of nonwoven goods and to nonwoven goods having an improved rate of water absorption. Such goods are made by incorporating vinyl acetate-ethylene-crosslinkable monomer emulsions prepared by the improved process into a loosely assembled web of fibers in a conventional manner. The copolymer is produced by a process for producing an aqueous emulsion suitably adapted for producing non-woven goods said emulsion containing a vinyl acetate-ethylene-crosslinkable monomer copolymer wherein said copolymer contains from about 60-96% by weight of vinyl acetate. In the basic process the copolymer is produced by forming an aqueous suspension of vinyl acetate, ethylene, and stabilizer, initiating the polymerization of the reaction mixture by the addition of catalyst, and then adding crosslinkable monomer during the polymerization to provide from about 0.5-10% crosslinkable by weight of the copolymer. The improvement for enhancing the properties of said emulsion comprises:
pressurizing the reactor with ethylene to an initial ethylene equilibrium pressure of from about 100 to 1,000 psig;
initiating the reaction mixture by the addition of catalyst at a temperature from about 10°-35° C. and bringing the reaction mixture to a reaction temperature of from 45°-85° C. and operating pressure within a period of not more than 2 hours and the reaction temperature exceeds the initiation temperature by at least 20° C.;
adding the crosslinkable monomer at a substantially uniform rate such that the major portion of monomer has been added by the time the vinyl acetate content in the emulsion has been reduced to a level of from 3-25% by weight of the emulsion;
and
continuing polymerization of the reaction mixture until the vinyl acetate content in said emulsion is reduced below about 1% by weight.
There are several advantages associated with this process for producing emulsions adapted for nonwoven goods. These are:
First, one achieves a highly energy efficient process by utilizing the heat of reaction to bring the reaction mixture to the reaction temperature and operating pressure;
Second, one achieves a shortened reaction time by virtue of the fact that polymerization is carried out under conditions normally allocated to heat-up and pressurization. The prior art techniques of requiring heat-up to operating temperatures of from 50° to 70° C. prior to initiating require a time delay for these features.
Third, and one of the most significant advantages of the process, is that the particular vinyl acetate-ethylene-crosslinkable monomer containing copolymer has outstanding rates of water absorption. This property makes it highly attractive for preparing nonwoven goods for specific applications, e.g., paper towels.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Several steps are important in the process for forming aqueous emulsions containing vinyl acetate-ethylene-crosslinkable monomer containing copolymer which are suitable for obtaining the advantages described above. The first step, as with most of the other vinyl acetate-ethylene aqueous emulsion processes, lies in the formation of an aqueous emulsion of vinyl acetate and other components used in the reaction mixture. In this regard, the water is first mixed with a stabilizer, e.g. from about 0.5-5% protective colloid or surfactant, or both, by weight of the copolymer. Then the reducing agent of the redox catalyst system and other components e.g. buffers are added as needed to form a premix. The premix is then charged to the reactor and the vinyl acetate added. Optionally, the vinyl acetate can be added to the premix. Substantially all, at least 75% by weight, and preferably 100% of the vinyl acetate is added prior to initiation.
Reducing agents, stabilizers, buffers and catalysts used in the practice of this invention are conventional and used in conventional amounts. Examples of reducing agents include the sulfoxylates, bisulfites, and ferrous salts. Specific examples include sodium and zinc formaldehyde sulfoxylate. Catalysts include hydrogen peroxide and benzoyl peroxide. Stabilizing agents include nonionic emulsifying agents such a polyoxyethylene condensates, e.g. polyoxyethylene aliphatic ethers and polyoxyethylene esters of higher fatty acids. Specific examples include polyoxyethylene nonyl phenyl ether and polyoxyethylene laurate; and polyoxyethyleneamides such as N-polyoxyethylenelauramide. The stabilizers are often used in combination with a protective colloid, e.g. hydroxyethyl cellulose or a partially acetylated polyvinyl alcohol. Polyvinyl alcohol protective colloids having a hydrolysis value of from about 80 to 94 and preferably from about 87 to 89% by weight are generally used. Other examples of stabilizers, emulsifying agents, buffers, amounts and methods for forming the emulsion are shown in U.S. Pat. No. 3,380,851 and are incorporated by reference.
After the stabilizer, reducing agent, etc. is dissolved in the mixture of water and vinyl acetate, the premix then can be charged to the reactor (unless made up in the reactor itself). Thereafter, the reactor is initially pressurized with ethylene to provide a minimum ethylene equilibrium pressure of from about 100-1,000 psig. This pressure may be generally less than the operating pressure. Agitation is effected during pressurization and typically ethylene is introduced by subsurface means through spargers to insure that ethylene is rapidly transferred to the vinyl acetate.
Prior to initiation the reaction mixture is adjusted to a temperature of from about 10°-35° C., preferably 15°-30° C. Pressurization of the reaction mixture with ethylene may be prior to or subsequent to this adjustment step. Typically, for commercial reactions, this will be from 400-750 psig. After the reaction mixture is brought to an initial temperature, and the ethylene is present in the vinyl acetate, polymerization of the reaction mixture is commenced by the addition of either the oxidizing or reducing component of the catalyst. Low Tg, e.g. -20° to +5° C. (Tg=glass transition temperature) copolymers can be prepared by adding some ethylene during the reaction or toward the end of the reaction. The amount of ethylene required at the end will depend upon how much ethylene is added in the initial charge and the free space in the reactor.
A crosslinkable monomer is used in preparing the emulsion in an amount to provide from about 0.5 to about 10% by weight, typically from about 2-5% by weight in the copolymer. These crosslinkable monomers are the post-reactive type, i.e., they will cross link upon the application of heat or addition of appropriate catalyst or reactive component to form a thermoset resin. Examples of crosslinkable monomers suited for practicing this invention are the N-methylol amides e.g. N-methylol acrylamide and N-methylol methacrylamide and their lower alkyl (C 1-6 ) ethers. In addition crosslinkable monomers such as N-methylol allyl carbamate and lower alkyl (C 1-6 ) ethers thereof are suited for practicing the invention. In addition crosslinkable functionality can be imparted by the addition of acids e.g. acrylic and methacrylic acid, acrylamide, unsaturated dicarboxylic acids, e.g. crotonic acid, maleic acid, itaconic acid; and glycidyl acrylate and glycidyl methacrylate.
Most of the crosslinkable monomers suited for producing vinyl acetate-ethylene emulsions particularly adapted for nonwoven goods have a polymerization reactivity greater than vinyl acetate. Such monomers are added at a uniform rate and incrementally during the polymerization to obtain a uniform copolymer. Typically, the addition of the crosslinkable monomer is carried out so that a major portion, e.g. greater than 75%, and preferably all of the monomer is added by the time the vinyl acetate content in the emulsion is reduced to a level from about 3-25%, and preferably 3-8% by weight of the emulsion.
On initiation, the temperature of the reaction mixture begins to rise and on continued addition of catalyst the temperature, and sometimes the pressure, will increase rapidly. Catalyst addition is adjusted to reach a reaction temperature of from about 45° to 85° C., typically 50°-55° C. within about 2 hours, and preferably within 1 hour, and then it is added at a rate to maintain such temperature. The reaction temperature is set to be at least 20° C. above the initiation temperature, and preferably at least 25° C. The reactor is initially pressurized to a preselected initial pressure that will provide a desirable operating pressure, e.g., of from 300-1,500 psig at the reaction temperature. Additional ethylene may be added during the polymerization to produce a copolymer having from about 60 to 96% vinyl acetate. Typically this level of vinyl acetate will translate into a copolymer having a glass transition temperature (Tg) of from about -30° to 20° C.
The vinyl acetate-ethylene-crosslinkable monomer system described are suitably used to prepare nonwoven fabrics by a variety of methods known to the art which, in general, involve impregnation of a loosely assembled mass of fibers with the emulsion followed by moderate heating to dry the mass and effect crosslinking of the binder to achieve a thermoset system. Depending upon the crosslinkable monomer used in the vinyl acetate system a catalyst can be incorporated into the emulsion prior to its application to the loosely assembled mass of fibers or applied subsequent thereto and cured by conventional technique. Acid catalysts such as mineral acids, e.g. hydrochloric aid or organic acids and acid salts such as ammonium chloride are suitably used for effecting cure of an N-methylol containing system, i.e. N-methylol acrylamide or its ethers.
The starting layer or mass can be formed by any one of the conventional techniques for depositing or arranging fibers in a web or layer. These techniques include carding, garnetting, air laying and the like. Individual webs or thin layers prepared by one or more of these techniques can be laminated to provide a thicker layer. Specific examples of nonwoven goods prepared by applying the emulsions of this invention to the webs or laminated layers include paper towels, tissues, sanitary napkins, filter cloths, wrappings for food products, bandages, surgical dressings, etc.
STATEMENT OF INDUSTRIAL APPLICATION
The copolymers of vinyl acetate-ethylene crosslinkable monomers of this invention have excellent water absorption rates, thus making them well suited for use in producing nonwoven goods.
The following examples are provided to illustrate the preferred embodiment of the invention are not intended to restrict the scope thereof.
EXAMPLE 1
A series of polymerization runs were made for preparing a vinyl acetate-ethylene copolymer system in a 15 gallon stirred, stainless steel autoclave, the agitation system involving 2 turbine blades being rotated at 180-200 rpm. Then a premix, either recipe 1 or 2 as described, consisting of vinyl acetate (substantially all is changed, i.e. greater than 80%), water, surfactant and reducing agent, consisting of a ferrous ion in the form of ferrous ammonium sulfate (1% solution), was charged to the reactor. After charging the recipe to the reactor, the reactor was purged with nitrogen and ethylene. Ethylene was then charged to the reactor via subsurface feed and the reactor pressurized to a preselected initial pressure, i.e. either 460 or 700 psig. Once the ethylene was incorporated into the premix polymerization was initiated by addition of oxidizing agent.
In the Tables below essentially two recipes were used. Recipe 1 was used in producing -17° C. Tg product and generally consisted of:
______________________________________ RECIPE 1______________________________________Vinyl acetate 40 poundsAlipal CO-433 (30%)solution 1,616 grams variable 2-3%Igepal CO-430 75.7 gramsFerrous ion 1 gramDistilled water 30 pounds______________________________________
Recipe 2 was used to produce 0° C. Tg product, and generally consisted of:
______________________________________RECIPE 2______________________________________Vinyl acetate 50 poundsAlipal CO-433 (30%)solution surfactant 4.3 pounds-variable 2-4%Igepal CO-430surfactant 250 gramsFerrous ion 1.0 gramsDistilled water 31 pounds______________________________________
In carrying out the polymerization reaction times were calculated to be complete within about 3 hours. Assuming that the initial vinyl acetate monomer concentration in the reactor prior to initiation was about 60%, the vinyl acetate content at the end of 1 hour should be approximately 40%, 20% at the end of second hour and less than 1% at the end of third hour. Based on this conversion rate of vinyl acetate the crosslinkable monomer was added to the reaction mixture at a rate such that all of the monomer would be added to the reactor by the time the unreacted vinyl acetate monomer content in the emulsion was from 3 to 8% by weight. The monomer in Runs 1 to 16 were in the 3 to 8% vinyl acetate content range. Runs 17 and 18 were about 20% vinyl acetate content. This level is reached in about 21/2 hours thus the crosslinkable monomer was added at a uniform rate (±50%), preferably 120% for 21/2 hours. Polymerization was carried out using an activator solution consisting of zinc formaldehyde sulfoxylate (about 7% by weight) and a catalyst system consisting of a peroxide, e.g., t-butyl hydroperoxide or 2% hydrogen peroxide. The grams hydrogen peroxide added per reaction was about 19 to 22 grams for recipes one and two and 26 to 30 grams of zinc formaldehyde sulfoxylate (7.1% solution).
Table 1 below provides data with respect to several vinyl acetate-ethylene emulsions run which were designed to compare favorably to commercially available vinyl acetate-ethylene-N-methylol acrylamide (control) emulsions having Tg's of 0±3 and -16°±2° C., respectively. The process utilized in preparing the commercial emulsions comprises initiating polymerization after the mixture of ethylene and premix had been preheated to the reaction temperature, i.e., 50° C. That temperature was maintained and crosslinkable monomer added on a continuous basis. Initial ethylene pressures are given and runs 1-3A relate to a control emulsion having a Tg of -17° to -20° C. and runs 5-16 relate to a control type emulsion having a Tg of 0°±3° C.
TABLE I__________________________________________________________________________ INITIAL ETHYLENE PERCENTRUN SURFACTANT % PSIG CAT AA AM NMA__________________________________________________________________________1 Triton 301 3 700 TBHP -- -- 3.452 Triton 301 3 700 TBHP 3.453 Igepal 430 Alipal CO433 2 700 H.sub.2 O.sub.2 5.03A Igepal 430 Alipal CO433 2 700 1 5.04 Triton 301 3.0 460 H.sub.2 O.sub.2 5.05 Igepal CO430 Alipal CO433 3.0 460 H.sub.2 O.sub.2 0.56 Igepal CO430 Alipal CO433 " " " 1.07 Igepal CO430 Alipal CO433 " " " 0.5 3.58 Igepal CO430 Alipal CO433 " " " 2.0 3.59 Igepal CO430 Alipal CO433 " " " 1.23 1.7510 Igepal CO430 Alipal CO433 " " " 2.0 0.31 2.611 Igepal CO430 Alipal CO433 " " " -- -- 5.012 Igepal CO430 Alipal CO433 " " " -- 2.0 2.513 Igepal CO430 Alipal CO433 " " 1.75 2.514 Igepal CO430 Alipal CO433 " " 3.0 5.015 Igepal CO430 Alipal CO433 " " " 1.2 3.516 Igepal CO430 Alipal CO433 " " " 3.0 3.517 Igepal CO430 Alipal CO433 " " TBHP 2.0 2.5.sup.a18 Igepal CO430 Alipal CO433 " " TBHP 2.0 2.5.sup.b__________________________________________________________________________ Peak pressures of from 800-1100 psig were reached during the polymerization runs. .sup.a The NMA was added in 1.5 hours based upon a 3hour reaction time. .sup.b The NMA was added in 3 hours based upon a 5hour reaction time.
In the above tables CAT refers to Catalyst, AA refers to acrylic acid, AM refers to acrylamide, NMA refers to N-methylol acrylamide and is expressed in percent on the basis of all vinyl acetate and estimated ethylene content added to the reaction. Triton X-301 is the sodium salt of alkylaryl polyether sulfate; Igepal 430 which is Igepal, 630 which is a acetylphenoxypoly(ethlenoxy) ethanol, Alipal 433 is a sodium salt of sulfated nonyl phenoxy poly(ethyleneoxy) ethanol.
TBHP refers to t-butyl hydroperoxide. With respect to Table II % solids were measured as Cenco balance solid. Brookfield viscosity is measured using a Brookfield viscometer at 25° C. No. 2 spindle. The symbol ' represents minutes, and " represents seconds.
In evaluating the effectiveness of the copolymer in terms of producing non-woven goods, No. 4 Whatman chromotography paper was impregnated with the emulsion at various "add on" levels, i.e., the weight of copolymer vs. the weight of the paper and then evaluated in conventional manner. The tensile strength under dry, wet (water) and perchlor conditions were measured with an Instron testing machine. Wet and perchlor testing is carried out by immersing the paper having cured copolymer thereon into water and perchloroethylene, respectively, for a period of about 1 minute and then removing. Tensile strengths are measured in the cross machine direction (CMD) at a chart speed of 0.5 inches per minute. The wicking time and sinking time are measured by ASTM test D-1117 and corresponds to a rate of absorption. Table II shows these results.
TABLE II__________________________________________________________________________ % ADD ON DRY WET PERCHLORRUN SOLIDS VISC. pH % lbs lbs lbs WICKING SINKING__________________________________________________________________________Tg-0° C. Control 51.4 886 4.9 20 20.9 11.3 10.4 2'34" 2.84' AveTg-0° C. Control 51.4 886 4.9 30 21.6 12.8 17.2 1'52"-3'47" 4.78'Tg-17° C. Control 10 12.3 6.6 6.99 14'24" AveTg-17° C. Control 10 13.7 5.8 6.1 14'24" Ave1 -- -- -- 11 13.7 5.8 7.0 2'102 -- -- -- 10 12.6 5.8 7.0 2'303 -- -- -- 10 11.5 4.69 7.49 2'30"3A -- -- -- 10 13.8 6.6 8.59 4'6"4 55 225 5.4 20 19.2 9.3 9.6 14" 14"5 47 34.2 5.1 20 21.1 10.4 10.8 24" 23"6 53.8 244 5.0 20 208 10.4 16.7 39" 39"7 55 106 4.8 20 17.1 8.8 9.8 49" 49"8 54.4 84.5 4.5 30 22.9 11.5 11.4 11"9 54.6 113.5 5.3 32 20.3 10.0 15.6 21"10 54.6 95.0 4.7 31 23.0 9.9 18.3 13"11 53.0 239 4.7 30 23.9 9.4 15.0 30"12 53.1 140 4.3 10 11.5 4.5 6.4 18.6" 17.4"13 55.2 247 4.5 22 19.6 9.4 9.5 38"14 51.9 197 4.6 20 18.1 7.4 8.1 27"15 52.9 56.2 4.7 19 18.4 7.3 7.1 25"16 53.4 782 4.5 21 18.5 7.2 7.1 26"17 54.4 50.6 4.5 20 18.1 9.5 6.7 39" 3918 53.9 73 4.8 20 16.5 8.8 5.8 80.4" 80.4"__________________________________________________________________________
From the above tables it can be seen that tensile strength of the non-woven goods prepared using the emulsions of this invention compare favorably with those of similar prior art commercial emulsions. The big difference is noted in the rate of absorption of the non-woven goods. There is a clear difference between the commercial emulsions and the emulsions of this invention. Wicking time for the emulsions of this invention which are comparable to the control emulsions namely 1-3A in time for the -17° C. Tg material is from about 2 minutes to about 5 minutes whereas the average for the commercial emulsion is approximately 14 minutes. When comparing runs 4-16 to the 0° C. Tg control wicking times of from about 10 to 60 seconds were recorded whereas wicking times of 2 minutes to about 31/2 minutes were recorded for the control. These results clearly show that copolymers of this invention, regardless of the add-on quantity, resulted in significantly shorter wicking times than the commercially available vinyl acetate-ethylene-N-methylol acrylamide emulsions. Further, the runs showed that wicking time is substantially independent of the add-on of copolymer incorporated into the non-woven good or the type of monomer.
Triton X-301 is the sodium salt of alkylaryl polyether sulfate; Igepal 430 which is Igepal, 630 which is a acetylphenoxypoly(ethlenoxy) ethanol, Alipal 433 is a sodium salt of sulfated nonyl phenoxy poly(ethyleneoxy) ethanol. | This invention relates to a vinyl acetate-ethylene copolymer containing emulsion particularly adapted for the preparation of nonwoven goods. The vinyl acetate-ethylene emulsion is prepared by an improved process for producing an aqueous emulsion suitably adapted for producing non-woven goods said emulsion containing a vinyl acetate-ethylene copolymer wherein said copolymer contains from about 75-96% by weight of vinyl acetate. It is produced by forming an aqueous suspension of vinyl acetate, ethylene, and stabilizer, initiating the polymerization of the reaction mixture by the addition of catalysts, and adding from about 0.5-10% by weight of the vinyl acetate of a crosslinkable monomer. The improvement for enhancing the absorptivity of the copolymer comprises:
pressurizing the reactor with ethylene to an initial ethylene equilibrium pressure of from about 100 to 1,000 psig;
initiating the reaction mixture by the addition of catalyst at a temperature from about 10°-35° C. and bringing the reaction mixture to a reaction temperature of from 45°-85° C. and operating pressure within a period of not more than 2 hours and the reaction temperature exceeds the initiation temperature by at least 20° C.;
adding the crosslinkable monomer at a substantially uniform rate such that the major portion of monomer has been added by the time the vinyl acetate content in the emulsion has been reduced to a level of from 3-25% by weight of the emulsion;
and
continuing polymerization of the reaction mixture until the vinyl acetate content in said emulsion is reduced below about 1% by weight. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a liquid crystal display device which uses a nematic crystal composition having positive dielectric anisotropy (Δ∈>0).
2. Description of the Related Art
Currently, regarding the devices of the active matrix drive system, display modes such as an optically compensated bend (OCB) mode, a vertical alignment (VA) mode and an in-plane switching (IPS) mode have been applied, due to their display quality, to portable terminals, liquid crystal TV sets, projectors, computers, and the like. Since an active matrix display system has a non-linear circuit provided for each pixel, and it has been suggested to use a thin film transistor (TFT) using amorphous silicon or polysilicon, or an organic semiconductor material. Furthermore, as a method for the alignment of liquid crystal molecules to cope with an increase in display size or high definition display, it has been suggested to use a photo-alignment technology. It has been suggested to use a phase difference film in order to obtain wider viewing angle characteristics for the display, or to use a photopolymerizable monomer in order to obtain clear display (SID Sym. Digest, 277 (1993); SID Sym. Digest, 845 (1997); SID Sym. Digest, 1077 (1998); SID Sym. Digest, 461 (1997); Proc. 18 th IDRC, 383 (1998); SID Sym. Digest, 1200 (2004); Proc. Asia Display, 577 (1995); and Proc. 18 th IDRC, 371 (1998)).
However, in order for liquid crystal display television sets to completely replace the conventional television sets utilizing cathode ray tubes (CRT) and to also cope with the demand for 3D imaging or field sequential display, liquid crystal TVs are still not satisfactory in terms of the response speed and viewing angle characteristics. For example, the IPS mode is excellent in the viewing angle characteristics, but is not satisfactory in terms of the response speed; and the VA mode exhibits a relatively fast response speed, but is not satisfactory in terms of the viewing angle characteristics. Accordingly, in addition to the use of the overdrive mode, an amelioration for enhancing the apparent response speed of display elements by changing the frame frequency from 60 Hz to a high frequency such as 120 Hz or 240 Hz, has been in progress. However, there are limitations in overcoming the limit of the response speed that is intrinsic to a liquid crystal material, if amelioration is made only in terms of the electronic circuit of these liquid crystal display devices. Thus, there is a demand for a drastic improvement in the response speed as a result of amelioration in the entirety of a display device including a liquid crystal material.
Furthermore, in order to improve the viewing angle characteristics in regard to the VA mode, a multi-domain vertical alignment (MVA) mode has been suggested in which the viewing angle characteristics are improved by partitioning the pixels, and changing the direction of orientation of the liquid crystal molecules for each of the partitioned pixels. In this mode, it is possible to improve the viewing angle characteristics; however, since it is required to produce liquid crystal cells that have a complicated structure uniformly in order to achieve pixel partitioning, a decrease in production efficiency has been unavoidable.
As a method of drastically improving such a problem, new drive systems that are different from the conventional drive systems have been suggested. For example, there is known a method of aligning a liquid crystal material having positive dielectric anisotropy (Δ∈>0) perpendicularly to the substrate surface without voltage application, and driving liquid crystal molecules in a transverse electric field generated by the electrodes disposed on the substrate surface (JP 57-000618 A; JP 50-093665 A; JP 10-153782 A; JP 10-186351A; JP 10-333171A; JP 11-024068 A; JP 2008-020521A; Proc. 13 th IDW, 97 (1997); Proc. 13 th IDW, 175 (1997); SID Sym. Digest, 319 (1998); SID Sym. Digest, 838 (1998); SID Sym. Digest, 1085 (1998); SID Sym. Digest, 334 (2000); and Eurodisplay Proc., 142 (2009)). In this method, as an electric field in the transverse direction curves, liquid crystal molecules align in a different direction when a voltage is applied; therefore, multiple domains can be formed without performing pixel partitioning as in the case of the MVA mode described above. Accordingly, the method is excellent in view of production efficiency. Liquid crystal display devices of such a mode are called, according to JP 10-153782 A; JP 10-186351A; JP 10-333171A; JP 11-024068 A; JP 2008-020521A; Proc. 13 th IDW, 97 (1997); Proc. 13 th IDW, 175 (1997); SID Sym. Digest, 319 (1998); SID Sym. Digest, 838 (1998); SID Sym. Digest, 1085 (1998); SID Sym. Digest, 334 (2000); and Eurodisplay Proc., 142 (2009), by various names such as EOC and VA-IPS, but in the present invention, the display mode will be hereinafter abbreviated as “VAIPS”.
However, in the VAIPS mode, since the physical behavior of liquid crystal molecules is different from the conventional method for driving a liquid crystal display device, it is required to select a liquid crystal material under a criterion different from the conventional criteria in connection with the liquid crystal material.
That is, in general, the threshold voltage (Vc) of Fréedericksz transition in a twisted nematic (TN) mode is represented by the following formula:
Vc
=
π
d
cell
d
cell
+
〈
r
1
〉
K
11
Δ
ɛ
;
[
Mathematical
Formula
1
]
the same threshold voltage in a super-twisted nematic (STN) mode is represented by the following formula:
Vc = π d gap d cell + 〈 r 2 〉 K 22 Δ ɛ ; [ Mathematical Formula 2 ]
and
the same threshold voltage in the VA mode is represented by the following formula:
Vc = π d cell d cell - 〈 r 3 〉 K 33 Δ ɛ [ Mathematical Formula 3 ]
wherein Vc represents the Fréedericksz transition (V); π represents the ratio of the circumference of a circle to its diameter; d cell represents the distance (μm) between a first substrate and a second substrate; d gap represents the distance (μm) between a pixel electrode and a common electrode; d ITO represents the width (μm) of the pixel electrode and/or common electrode; <r1>, <r2> and <r3> represent extrapolation lengths (μm); K11 represents the elastic constant (N) of splay; K22 represents the elastic constant (N) of twist; K33 represents the elastic constant (N) of bend; and Δ∈ represents dielectric anisotropy.
However, in the VAIPS mode, since these general calculation formulas do not fit, and no criteria for selecting the liquid crystal material are available, there has been no progress in the improvement of performance, and consequently, application thereof into liquid crystal display devices has been delayed.
On the other hand, in regard to the VAIPS mode, disclosures have also been made on preferred compounds as the liquid crystal material to be used (JP 2002-012867 A). However, the liquid crystal composition described in the relevant reference document uses a cyano-based compound, and therefore, the liquid crystal composition is not suitable for active matrix applications.
Liquid crystal display devices also have a problem of aiming to achieve mega contrast (CR) by enhancing the black level with a bright luminance. It has been suggested to improve the numerical aperture so as to enable increasing the pixel display area of LCDs, to apply a luminance enhancing film such as a dual brightness enhancement film (DBEF) or a cholesteric liquid crystal (CLC) film, or to reduce the light leakage caused by protrusions and the like when the liquid crystal is subjected to vertical alignment. Furthermore, there is also a demand for a display which is not easily brought into disorder even under a pressing pressure in a touch panel system.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a liquid crystal display device of the VAIPS mode which uses a liquid crystal material having positive dielectric anisotropy (hereinafter, referred to as p-VAIPS), and which has a fast response speed and excellent viewing angle characteristics without having a special cell structure such as pixel partitioning. According to the invention, a liquid crystal display device which provides a display with a higher response speed that has been a problem of the related art technologies, achieves widening of the viewing angle more effectively, exhibits a high luminance at the time of light transmission and a high black level at the time of light blockage, and thereby enables an improvement to obtain a high contrast ratio.
The inventors of the present invention conducted a thorough investigation in order to solve the problem described above, and as a result, they found that the problem can be solved by combining a VAIPS liquid crystal display device having a particular structure and a liquid crystal composition containing a particular liquid crystal compound, thus completing the titled invention of the invention.
According to an aspect of the invention, there is provided a liquid crystal display device including a first substrate, a second substrate, and a liquid crystal composition layer having positive dielectric anisotropy that is interposed between the first substrate and the second substrate, the liquid crystal display having plural pixels, with each of the pixels being independently controllable and having a pair of a pixel electrode and a common electrode, these two electrodes being provided on at least one substrate of the first and second substrates, the long axis of the liquid crystal molecules of the liquid crystal composition layer being in an alignment substantially perpendicular to the substrate surface or in a hybrid alignment, the liquid crystal composition containing one kind or two or more kinds of compounds selected from the group consisting of compounds represented by General Formula (LC1) to General Formula (LC5):
wherein R 1 represents an alkyl group having 1 to 15 carbon atoms; one or two or more CH 2 groups in the alkyl group may be substituted by —O—, —CH═CH—, —CO—, —COO—, —COO—, —C≡C—, —CF 2 O— or —OCF 2 — such that O atoms are not directly adjacent to each other; one or two or more H atoms in the alkyl group may be optionally substituted by halogen; A 1 , A 2 and A 3 each independently represent any one of the following structures:
(wherein X 1 and X 2 each independently represent H, Cl, F, CF 3 or OCF 3 ); one or two or more CH 2 groups in A 1 and A 2 may be substituted by —CH═CH—, —CF 2 O— or —OCF 2 —; one or two or more CH groups in A 1 and A 2 may be substituted by N atoms; one or two or more H atoms in A 1 and A 2 may be substituted by Cl, F, CF 3 or OCF 3 ; X 1 to X 5 each independently represent H, Cl, F, CF 3 or OCF 3 ; Y represents Cl, F, CF 3 or OCF 3 ; Z 1 to Z 4 each independently represent a single bond, —CH═CH—, —C≡C—, —CH 2 CH 2 —, —(CH 2 ) 4 —, —OCH 2 —, —CH 2 O—, —OCF 2 — or —CF 2 O—; at least one of Z 1 and Z 2 that exist is not a single bond; Z 5 represents a CH 2 group or an O atom; m 1 and m 2 each independently represent an integer from 0 to 3; m 1 +m 2 represents 1, 2 or 3; and m 3 each independently represent an integer from 0 to 2, and the transmittance of the light that penetrates through the liquid crystal composition layer is modulated at the electric field generated by the electrode structure.
In the invention, the long axis of the liquid crystal molecules in the substrate is aligned substantially perpendicularly to the substrate surface, or is in a hybrid alignment. Here, the hybrid alignment means a state in which the long axis of the liquid crystal molecules interposed between two sheets of substrates is aligned substantially in parallel to the substrate surface on one of the substrate side, and the long axis is aligned substantially perpendicularly on the other substrate side. In the present specification, the state in which the long axis of the liquid crystal molecules is aligned substantially perpendicularly is referred to as p-VAIPS, and the state in which the long axis is in a hybrid alignment is referred to as p-HBIPS. Furthermore, regarding the electrode structures of the p-VAIPS and p-HBIPS modes, the electrode structure of the conventional transverse electric field modes such as IPS, fringe-field switching (FFS) and improved FFS can be applied.
The behavior of liquid crystal molecules in the present invention is schematically described in FIG. 1 to FIG. 3 , and the liquid crystal molecules undergo transition from the state without voltage application as illustrated in FIG. 1 to the state under voltage application as illustrated in FIG. 2 or FIG. 3 . At this time, an increase in the response speed can be promoted by adopting a bend alignment state, which is advantageous in the flow effect. In general, the response speed is 20 msec to 40 msec in the IPS mode, and 10 msec to 30 msec in the TN mode; however, the response speed in the invention is 1 msec to 8 msec, which implies that a drastic improvement has been achieved.
In a conventional drive method of the TN mode, generally, a special optical film or the like must be used for the widening of the viewing angle, and thus the widening of the viewing angle is achieved only in a horizontal direction or in a vertical direction. On the other hand, in a drive method of the VA mode, although the viewing angle is generally wide, it is necessary to define the direction of tilt of the liquid crystal molecules by using zone rubbing, protrusions, a slit electrode, and the like, and to promote formation of multiple domains, and thus, the cell configuration tends to become complicated. In the p-VAIPS and p-HBIPS modes of the invention, since the direction of tilt of the liquid crystal molecules can be defined by utilizing the line of electric force generated by the applied voltage, the formation of multiple domains can be achieved only by means of the shape of the pixel electrode, a relatively simple cell configuration is sufficient for operation, and an increase in the viewing angle and an increase in contrast can be achieved.
Further, in general, the value of the Fréedericksz transition (Vc) is represented by Formula (1) in the TN mode, by Formula (2) in the STN mode, and by Formula (3) in the VA mode. However, it was found that the following Mathematical Formula (4) is applicable to the liquid crystal display device of the invention:
Vc ∝ d gap - 〈 r ′ 〉 d ITO + 〈 r 〉 π d cell d cell - 〈 r 3 〉 K 33 Δ ɛ [ Mathematical Formula 4 ]
wherein Vc represents the Fréedericksz transition (V); π represents the ratio of the circumference of a circle to its diameter; d cell represents the distance (μm) between a first substrate and a second substrate; d gap represents the distance (μm) between a pixel electrode and a common electrode; d ITO represents the width (μm) of the pixel electrode and/or common electrode; <r>, <r′> and <r3> represent extrapolation lengths (μm); K33 represents the elastic constant (N) of bend; and Δ∈ represents dielectric anisotropy. Regarding the cell configuration according to Mathematical Formula 4, it was found that a decrease in the driving voltage can be attempted by making the value of d gap as low as possible, and the value of d ITO as high as possible, and regarding the liquid crystal composition used, a decrease in the driving voltage can be attempted by selecting a high absolute value of Δ∈ and a low value of K33. Based on these findings, the inventors found a liquid crystal having negative positive dielectric anisotropy that is appropriate for the liquid crystal display device described above.
Further, the most prominent feature of the liquid crystal display device of the invention is that these liquid crystal molecules that can easily start moving start to move about not at the center between two sheets of substrates, but from a site that is shifted toward any one substrate surface and has been brought closer to one substrate, and this feature is different from that of the conventional TN, IPS, VA and OCB modes.
The invention has improved characteristics such as the response speed, amount of light transmission, light leakage caused by an external pressure such as the use of a touch panel, viewing angle and contrast ratio, and has realized a higher response speed, a larger amount of light transmission, a reduction in light leakage caused by an external pressure, a wider viewing angle, and a higher contrast ratio, as compared with liquid crystal display devices produced by the conventional technologies.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram illustrating the state of alignment of liquid crystal molecules without voltage application (an example of p-VAIPS);
FIG. 2 is a diagram illustrating the state of realignment of liquid crystal molecules at the time of voltage application (an example of p-VAIPS);
FIG. 3 is a diagram illustrating the state of realignment of liquid crystal molecules at the time of voltage application in the case where a common electrode is disposed below a pixel electrode, with an insulating layer interposed therebetween (FFS) (an example of p-VAIPS);
FIG. 4 is a diagram illustrating the electrode configuration of a test cell;
FIG. 5 is a diagram illustrating the state of alignment of liquid crystal molecules without voltage application (example 1 of p-HBIPS);
FIG. 6 is a diagram illustrating the state of realignment of liquid crystal molecules upon voltage application (example 1 of p-HBIPS);
FIG. 7 is a diagram illustrating the state of alignment of liquid crystal molecules without voltage application (example 2 of p-HBIPS); and
FIG. 8 is a diagram illustrating the state of realignment of liquid crystal molecules upon voltage application (example 2 of p-HBIPS).
DESCRIPTION OF REFERENCE NUMERALS
1 FIRST SUBSTRATE
2 LIGHT BLOCKING LAYER
3 ALIGNMENT LAYER
4 LIQUID CRYSTAL
5 ALIGNMENT LAYER
6 PIXEL ELECTRODE
7 COMMON ELECTRODE
8 SECOND SUBSTRATE
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The liquid crystal composition according to the invention contains a liquid crystal compound represented by any one of the General Formula (LC1) to General Formula (LC5). However, in these general formulas, R 1 is preferably an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, or an alkoxy group having 1 to 8 carbon atoms;
A 1 and A 2 are each independently preferably a 1,4-cyclohexylene group, a 1,4-phenylene group, a 3-fluoro-1,4-phenylene group, or a 3,5-difluoro-1,4-phenylene group;
X 1 to X 5 are each independently preferably H or F; Y is preferably F, CF 3 or OCF 3 ;
Z 1 to Z 4 are each independently preferably a single bond, —C≡C—, —CH 2 CH 2 —, —OCH 2 —, —CH 2 O—, —OCF 2 — or —CF 2 O—; any one of Z 1 to Z 4 that exist is —C≡C—, —CH 2 CH 2 —, —OCH 2 —, —CH 2 O—, —OCF 2 — or —CF 2 O—; among Z 1 to Z 4 , when there are substituents that exist elsewhere, these substituents are preferably single bonds;
m 1 and m 2 each independently represent an integer from 0 to 2; and m 1 +m 2 is preferably 1 or 2.
More preferably, the liquid crystal compound represented by any one of General Formula (LC1) to General Formula (LC5) are such that the compound of General Formula (LC1) is preferably a compound represented by any one of General Formula (LC1)-1 to General Formula (LC1)-4:
wherein R 1 represents an alkyl group having 1 to 15 carbon atoms; one or two or more CH 2 groups in the alkyl group may be substituted by —O—, —CH═CH—, —CO—, —COO—, —COO—, —C≡C—, —CF 2 O— or —OCF 2 — such that O atoms are not directly adjacent to each other; Y represents Cl, F, CF 3 or OCF 3 ; and X 1 , X 2 , L 1 and L 2 each represent H, Cl, F, CF 3 or OCF 3 ; and/or
the compound of General Formula (LC2) is preferably a compound represented by any one of the following General Formula (LC2)-1 to General Formula (LC2)-10:
wherein R 1 , Y and X 2 have the same meanings as R 1 , Y and X 2 in General Formula (LC2), respectively; L 1 , L 2 , L 3 and L 4 each represent H, Cl, F, CF 3 or OCF 3 ; and/or
the compound of General Formula (LC3) is preferably a compound represented by any one of the following General Formula (LC3)-1 to General Formula (LC3)-34:
wherein R 1 represents an alkyl group having 1 to 15 carbon atoms; one or two or more CH 2 groups in the alkyl group may be substituted by —O—, —CH═CH—, —CO—, —COO—, —COO—, —C≡C—, —CF 2 O— or —OCF 2 — such that O atoms are not directly adjacent to each other; one or two or more H atoms in the alkyl group may be optionally substituted by halogen; X 2 and X 4 each independently represent H, Cl, F, CF 3 or OCF 3 ; Z 1 represents a single bond, —CH═CH—, —C≡C—, —CH 2 CH 2 —, —(CH 2 ) 4 —, —OCH 2 —, —CH 2 O—, —OCF 2 — or —CF 2 O—; and m 1 represents an integer from 0 to 3; and/or
the compound of General Formula (LC4) is preferably a compound represented by any one of the following General Formula (LC4)-1 to General Formula (LC4)-8; and the compound of General Formula (LC5) is preferably a compound represented by any one of the following General Formula (LC5)-1 to General Formula (LC5)-6:
wherein R 1 , X 1 , X 2 , X 4 , X 5 and Y have the same meanings as R 1 , X 1 , X 2 , X 4 , X 5 and Y in General Formula (LC4) or General Formula (LC5).
A compound in which in regard to General Formula (LC1) and General Formula (LC2), R 1 is preferably an alkenyl and/or R 2 is preferably an alkoxy group or an alkenyloxy group; in regard to General Formulas (LC3) to (LC5), at least one of R 1 and R 2 is preferably an alkenyl; in regard to General Formula (LC3), at least one of Z 1 and Z 2 is —OCH 2 — or —CH 2 O—, is preferred.
Furthermore, it is preferable that the liquid crystal composition layer contain a compound represented by General Formula (LC6):
wherein R 1 , R 2 , Z 3 , Z 4 and m 1 have the same meanings as R 1 , R 2 , Z 3 , Z 4 and m 1 in General Formula (LC1) to General Formula (LC5), respectively; B 1 to B 3 each independently represent the following:
(wherein one or two or more CH 2 CH 2 groups in the cyclohexane ring may be substituted by —CH═CH—, —CF 2 O— or —OCF 2 —; and one or two or more CH groups in the benzene ring may be substituted by N atoms).
The compound represented by General Formula (LC6) is a compound represented by any one of the following General Formula (LC6)-1 to General Formula (LC6)-15:
wherein R 1 , R 2 , Z 3 and Z 4 have the same meanings as R 1 , R 2 , Z 3 and Z 4 in General Formula (LC6), respectively.
In regard to General Formula (LC6), R 1 and/or R 2 is preferably an alkenyl or alkenyloxy group; any one of Z 1 and Z 2 is —CH═CH—, —C≡C—, —CH 2 CH 2 —, —(CH 2 ) 4 —, —OCH 2 —, —CH 2 O—, —OCF 2 — or —CF 2 O—; and the other is preferably a single bond or —C≡C—.
The liquid crystal composition that is used in the invention preferably contains the compounds represented by General Formula (LC1) to (LC5) in an amount of 100% to 20% by mass, more preferably 100% to 40% by mass, and particularly preferably 100% to 60% by mass.
Furthermore, it is preferable that the liquid crystal composition contain two or more kinds of compounds for which Δ∈ in General Formula (LC1) to (LC5) is 4 or more.
Furthermore, the liquid crystal composition may contain one kind or two or more kinds of polymerizable compounds, and preferably, the polymerizable compound is a disc-shaped liquid crystal compound having a structure in which a benzene derivative, a triphenylene derivative, a truxene derivative, a phthalocyanine derivative or a cyclohexane derivative serves as a parent nucleus at the center of the molecule, and a linear alkyl group, a linear alkoxy group or a substituted benzoyloxy group is radially substituted as a side chain.
Specifically, the polymerizable compound is preferably a polymerizable compound represented by General Formula (PC1):
[Chemical Formula 11]
(P 1 -Sp 1 -Q 1 n 1 MG R 3 ) n 2 (PC1)
wherein P 1 represents a polymerizable functional group; Sp 1 represents a spacer group having 0 to 20 carbon atoms; Q 1 represents a single bond, —O—, —NH—, —NHCOO—, —OCONH—, —CH═CH—, —CO—, —COO—, —OCO—, —OCOO—, —OOCO—, —CH═CH—, —CH═CH—COO—, —OCO—CH═CH— or —C≡C—; n 1 and n 2 each independently represent 1, 2 or 3; MG represents a mesogen group or a mesogenic supporting group; R 3 represents a halogen atom, a cyano group or an alkyl group having 1 to 25 carbon atoms; one or two or more CH 2 groups in the alkyl group may be substituted by —O—, —S—, —NH—, —N(CH 3 )—, —CO—, —COO—, —OCO—, —OCOO—, —SCO—, —COS— or —C≡C— such that O atoms are not directly adjacent to each other; or R 3 represents P 2 -Sp 2 -Q 2 - (wherein P 2 , Sp 2 and Q 2 each independently have the same meanings as P 1 , Sp 1 and Q 1 )).
More preferably, the polymerizable compound is a polymerizable compound in which MG in General Formula (PC1) is represented by the following structure:
—C 1 —Y 1 C 2 —Y 2 n 3 C 3 — [Chemical Formula 12]
wherein C 1 to C 3 each independently represent a 1,4-phenylene group, a 1,4-cyclohexylene group, a 1,4-cyclohexenyl group, a tetrahydropyrane-2,5-diyl group, a 1,3-dioxane-2,5-diyl group, a tetrahydrothiopyrane-2,5-diyl group, a 1,4-bicyclo(2,2,2)octylene group, a decahydronaphthalene-2,6-diyl group, a pyridine-2,5-diyl group, a pyrimidine-2,5-diyl group, a pyrazine-2,5-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, a 2,6-naphthylene group, a phenanthrene-2,7-diyl group, a 9,10-dihydrophenanthrene-2,7-diyl group, a 1,2,3,4,4a,9,10a-octahydrophenanthrene-2,7-diyl group, or a fluorene-2,7-diyl group; the 1,4-phenylene group, 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, 2,6-naphthylene group, phenanthrene-2,7-diyl group, 9,10-dihydrophenanthrene-2,7-diyl group, 1,2,3,4,4a,9,10a-octahydrophenanthrene-2,7-diyl group, and fluorene-2,7-diyl group may have, as substituents, one or more of F, Cl, CF 3 , OCF 3 , a cyano group, an alkyl group having 1 to 8 carbon atoms, an alkoxy group, an alkanoyl group, an alkanoyloxy group, an alkenyl group having 2 to 8 carbon atoms, an alkenyloxy group, an alkenoyl group, or an alkenoyloxy group; Y 1 and Y 2 each independently represent —COO—, —OCO—, —CH 2 CH 2 —, —OCH 2 —, —CH 2 O—, —CH═CH—, —C≡C—, —CH═CHCOO—, —OCOCH═CH—, —CH 2 CH 2 COO—, —CH 2 CH 2 OCO—, —COOCH 2 CH 2 —, —OCOCH 2 CH 2 —, —CONH—, —NHCO— or a single bond; and n 5 represents 0, 1 or 2. Sp 1 and Sp 2 each independently represent an alkylene group, and the alkylene group may be substituted with one or more halogen atoms or CN. One or two or more CH 2 groups that are present in this group may be substituted by —O—, —S—, —NH—, —N(CH 3 )—, —CO—, —COO—, —OCO—, —OCOO—, —SCO—, —COS— or —C≡C— such that O atoms are not directly adjacent to each other, and P 1 and P 2 are each independently represented by any one of the following General Formula (PC1-a) to General Formula (PC1-d):
wherein R 41 to R 43 , R 51 to R 53 , and R 61 to R 63 each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 5 carbon atoms.
More specifically, the polymerizable compound is preferably a polymerizable compound in which General Formula (PC1) is represented by General Formula (PC1)-1 or General Formula (PC1)-2:
[Chemical Formula 14]
(P 1 -Sp 1 -Q 1 n 3 MG Q 2 -Sp 2 -P 2 ) n 4 (PC1)-1
(P 1 -Q 1 n 3 MG Q 2 -P 2 ) n 4 (PC1)-2
wherein P 1 , Sp 1 , Q 1 , P 2 , Sp 2 , Q 2 and MG have the same meanings as P 1 , Sp 1 , Q 1 , P 2 , Sp 2 , Q 2 and MG of General Formula (PC1); and n 3 and n 4 each independently represent 1, 2 or 3.
More specifically, the polymerizable compound is more preferably a polymerizable compound in which General Formula (PC1) is represented by any one of General Formula (PC1)-3 to General Formula (PC1)-8:
wherein W 1 each independently represents F, CF 3 , OCF 3 , CH 3 , OCH 3 , an alkyl group having 2 to 5 carbon atoms, an alkoxy group, an alkenyl group, COOW 2 , OCOW 2 or OCOOW 2 (wherein W 2 represents a linear or branched alkyl group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 5 carbon atoms); and n 6 represents 0, 1, 2, 3 or 4.
Even more preferably, Sp 1 , Sp 2 , Q 1 and Q 2 in the General Formula (PC1) for the polymerizable compound are all single bonds; n 3 and n 4 are such that n 3 +n 4 is from 3 to 6; P 1 and P 2 are represented by formula (7-b); W 1 is F, CF 3 , OCF 3 , CH 3 or OCH 3 ; and n 6 represents 1 or more.
Furthermore, the polymerizable compound is also preferably a disc-shaped liquid crystal compound in which MG in General Formula (PC1) is represented by General Formula (PC1)-9:
wherein R 2 each independently represents P 1 -Sp 1 -Q 1 or a substituent of General Formula (PC1-e) (wherein P 1 , Sp 1 and Q 1 have the same meanings as P 1 , Sp 1 and Q 1 of General Formula (PC1), respectively); R 81 and R 82 each independently represent a hydrogen atom, a halogen atom or a methyl group; R 83 represents an alkoxy group having 1 to 20 carbon atoms; and at least one hydrogen atom in the alkoxy group is substituted by a substituent represented by any one of the General Formulas (PC1-a) to (PC1-d).
The amount of use of the polymerizable compound is preferably 0.1% to 2.0% by mass.
The liquid crystal composition can be used alone for the applications described above, may further include one kind or two or more kinds of oxidation inhibitors, or may further include one kind or two or more kinds of UV absorbers.
The product (Δn·d) of the refractive index anisotropy (Δn) of the liquid crystal composition with the distance (d) between the first substrate and the second substrate of a display device is, in the case of a vertical alignment, preferably 0.20 to 0.59; in the case of a hybrid alignment, preferably 0.21 to 0.61; in the case of a vertical alignment, particularly preferably 0.33 to 0.40; and in the case of a hybrid alignment, particularly preferably 0.34 to 0.44.
On each of the surfaces that are brought into contact with the liquid crystal composition on the first substrate and the second substrate of the display device, an alignment film formed from a polyimide (PI), a chalcone, a cinnamate or the like can be provided so as to align the liquid crystal composition, and the alignment film may also be a film produced using a photo-alignment technology.
In the case of vertical alignment, the tilt angle between the substrate and the liquid crystal composition is preferably 85° to 90°, and in the case of hybrid alignment, the tilt angle between the first substrate or the second substrate and the liquid crystal composition is 85° to 90°, while the tilt angle between the other substrate and the liquid crystal composition is preferably 3° to 20°.
EXAMPLES
Hereinafter, the invention of the present application will be described in detail by way of Examples, but the invention of the present application is not intended to be limited to these Examples. Furthermore, the unit “percent (%)” for the compositions of the following Examples and Comparative Examples means “percent (%) by mass”.
The properties of the liquid crystal composition will be indicated as follows.
T N-I : Nematic phase-isotropic liquid phase transition temperature (° C.) as the upper limit temperature of the liquid crystal phase
Δ∈: Dielectric anisotropy
Δn: Refractive index anisotropy
Vsat: Applied voltage at which the transmittance changes by 90% when square waves are applied at a frequency of 1 kHz
τr+d/msec: response speed obtainable when a cell with d ITO =10 μm, d gap =10 μm, and an alignment film SE-5300 for both the first substrate and the second substrate, was used.
The following abbreviations are used for the indication of compounds.
n (number) at the end
C n H 2n+1 —
-2-
—CH 2 CH 2 —
—1O—
—CH 2 O—
—O1—
—OCH 2 —
—V—
—CO—
—VO—
—COO—
—CFFO—
—CF 2 O—
—F
—F
—Cl
—Cl
—CN
—C≡N
—OCFFF
—OCF 3
—CFFF
—CF 3
—OCFF
—OCHF 2
—On
—OC n H 2n+1
-T-
—C≡C—
ndm-
C n H 2n+1 —HC═CH—(CH 2 ) m−1 —
Example 1
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the respective surfaces that faced each other. The liquid crystal composition having positive dielectric anisotropy indicated in Table 1 was interposed between the first substrate and the second substrate, and thus a liquid crystal display device of Example 1 was produced (deer: 4.0 μm, d ITO =10 μm, d gap =10 μm, alignment film: SE-5300). The property values of this liquid crystal display device are presented together in Table 1.
Comparative Example 1
A conventional TN liquid crystal display device was produced using the liquid crystal composition used in Example 1, and the property values were measured. The results are presented together in Table 2.
The liquid crystal display device of the invention realized a higher response speed, a larger amount of light transmission, a reduction in light leakage caused by external pressure, a wider viewing angle, and a higher contrast ratio, as compared with the liquid crystal display device of Comparative Example 1 in which the same liquid crystals having positive dielectric anisotropy were interposed.
Example 2
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical alignment was formed on each of the other sides of the respective surfaces that faced each other, and an alignment film of horizontal orientation was formed on each of the reverse sides. The liquid crystal composition having positive dielectric anisotropy indicated in Table 1 were interposed between the first substrate and the second substrate, and thus a liquid crystal display device of Example 2 was produced (d cell : 4.0 μm, d ITO =10 μm, d gap =10 μm, alignment film: SE-5300, AL-1051).
The liquid crystal display device realized a higher response speed, a larger amount of light transmission, a reduction in light leakage caused by external pressure, a wider viewing angle, and a higher contrast ratio, as compared with a conventional ECB liquid crystal display device in which the same liquid crystals having positive dielectric anisotropy were interposed.
Example 3
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the respective surfaces that faced each other. A composition obtained by adding 0.3% by mass of 2-methyl-acrylic acid 4′-{2-[4-(2-acryloyloxyethyl)phenoxycarbonyl]ethyl}biphenyl-4-yl ester to the liquid crystal composition having positive dielectric anisotropy indicated in Table 1 was interposed between the first substrate and the second substrate, and thus a liquid crystal display device of Example 3 was produced (d cell : 4.0 μm, d ITO =10 μm, d gap =10 μm, alignment film: SE-5300). While a driving voltage was applied between the electrodes, ultraviolet radiation was irradiated for 600 seconds (3.0 J/cm 2 ), and thus a polymerization treatment was carried out.
The liquid crystal display device realized a higher response speed, a larger amount of light transmission, a reduction in light leakage caused by external pressure, a wider viewing angle, and a higher contrast ratio, as compared with a conventional TN liquid crystal display device in which the same liquid crystals having positive dielectric anisotropy were interposed.
Example 4
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the other sides of the respective surfaces that faced each other. A composition obtained by adding 0.3% by mass of 2-methyl-acrylic acid 4′-{2-[4-(2-acryloyloxyethyl)phenoxycarbonyl]ethyl}biphenyl-4-yl ester to the liquid crystal composition having positive dielectric anisotropy indicated in Table 1 was interposed between the first substrate and the second substrate, and thus a liquid crystal display device of Example 4 was produced (d cell : 4.0 μm, d ITO =10 μm, d gap =10 μm, alignment film: SE-5300, AL-1051). While a driving voltage was applied between the electrodes, ultraviolet radiation was irradiated for 600 seconds (3.0 J/cm 2 ), and thus a polymerization treatment was carried out.
The liquid crystal display device realized a higher response speed, a larger amount of light transmission, a reduction in light leakage caused by external pressure, a wider viewing angle, and a higher contrast ratio, as compared with a conventional ECB liquid crystal display device in which the same liquid crystals having positive dielectric anisotropy were interposed.
TABLE 1
Example 1
Example 2
Example 3
Example 4
5-Cy-Ph-F
5
5
5
5
7-Cy-Ph-F
6
6
6
6
2-Cy-Cy-Ph-OCFFF
11
11
11
11
3-Cy-Cy-Ph3-F
12
12
12
12
3-Cy-Cy-Ph-OCFFF
12
12
12
12
3-Cy-Ph-Ph1-OCFFF
12
12
12
12
4-Cy-Cy-Ph-OCFFF
10
10
10
10
5-Cy-Cy-Ph3-F
9
9
9
9
5-Cy-Cy-Ph-OCFFF
12
12
12
12
5-Cy-Ph-Ph3-F
11
11
11
11
Sum of composition
100
100
100
100
ratios
Tni/° C.
91.8
91.8
91.8
91.8
Δn (20° C.)
0.093
0.093
0.093
0.093
Δε (20° C.)
11.3
11.3
11.3
11.3
Vsat/V (25° C.)
4.4
4.2
4.3
4.2
τr + d/msec (25° C.,
7.2
7.6
7.8
8.0
6 V)
Comparative Example 2
A liquid crystal display device of Comparative Example 2 was produced in the same manner as in Example 1 by interposing the liquid crystals having positive dielectric anisotropy indicated in Table 2, and the property values were measured. The results are presented in Table 2.
TABLE 2
Comparative
Comparative
Example 1
Example 2
5-Cy-Ph-F
5
5
7-Cy-Ph-F
6
6
2-Cy-Cy-Ph-OCFFF
11
11
3-Cy-Cy-Ph3-F
12
3-Cy-Cy-Ph1-OCFFF
12
3-Cy-Cy-Ph-OCFFF
12
12
3-Cy-Ph-Ph1-OCFFF
12
4-Cy-Cy-Ph-OCFFF
10
10
5-Cy-Cy-Ph3-F
9
9
5-Cy-Cy-Ph-OCFFF
12
12
5-Cy-Ph-Ph3-F
11
3-Ph-VO-Ph1-CN
11
3-Cy-Cy-Ph3-CN
8
3-Cy-Oc-Ph3-F
4
Sum of composition ratios
100
100
Tni/° C.
91.8
92.1
Δn (20° C.)
0.093
0.094
Δε (20° C.)
11.3
11.7
Vsat/V (25° C.)
3.9
5.6
τr + d/msec (25° C., 6 V)
17.6
11.7
The liquid crystal display device of Comparative Example 2 in which liquid crystals having positive dielectric anisotropy were interposed exhibited a slow response speed, a slightly smaller amount of light transmission, and particularly poor retention ratio and long-term reliability as compared with the liquid crystal display device of the invention.
Examples 5 to 7
A liquid crystal display device of Example 5 was produced in the same manner as in Example 1 by interposing the liquid crystals having positive dielectric anisotropy indicated in Table 3; a liquid crystal display device of Example 6 was produced in the same manner as in Example 1; and a liquid crystal display device of Example 7 was produced in the same manner as in Example 1.
TABLE 3
Example 5
Example 6
Example 7
5-Cy-Ph-F
5
5
6
7-Cy-Ph-F
6
6
6
2-Cy-Cy-Ph-OCFFF
11
11
11
3-Cy-Cy-Ph1-F
12
3-Cy-Cy-Ph1-OCFFF
9
3-Cy-Cy-Ph3-F
3-Cy-Cy-Ph3-OCFFF
12
3-Cy-Cy-Ph-OCFFF
12
12
12
3-Cy-Ph-Ph1-F
14
3-Cy-Ph-Ph1-OCFFF
12
12
4-Cy-Cy-Ph-OCFFF
10
10
10
5-Cy-Cy-Ph1-F
9
5-Cy-Cy-Ph1-OCFFF
10
5-Cy-Cy-Ph3-F
5-Cy-Cy-Ph3-OCFFF
9
5-Cy-Cy-Ph-OCFFF
12
12
10
5-Cy-Ph-Ph1-F
12
5-Cy-Ph-Ph1-OCFFF
11
11
5-Cy-Ph-Ph3-F
3-Ph-VO-Ph1-CN
3-Cy-Cy-Ph3-CN
3-Cy-Oc-Ph3-F
Sum of composition ratios
100
100
100
Tni/° C.
96.1
98.9
97.6
Δn (20° C.)
0.091
0.096
0.096
Δε (20° C.)
10.4
10.5
8.6
Vsat/V (25° C.)
4.5
5.2
5.8
τr + d/msec (25° C., 6 V)
7.4
6.9
6.7
The liquid crystal display devices of Examples 5 to 7 realized higher response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with conventional TN liquid crystal display devices in which the same liquid crystals having positive dielectric anisotropy were interposed.
Examples 8 to 10
A liquid crystal display device of Example 8 was produced in the same manner as in Example 1 by interposing the liquid crystals having positive dielectric anisotropy indicated in Table 4; a liquid crystal display device of Example 9 was produced in the same manner as in Example 1; and a liquid crystal display device of Example 10 was produced in the same manner as in Example 1.
TABLE 4
Example
Example 8
Example 9
10
5-Cy-Ph-F
5
5
5
7-Cy-Ph-F
6
6
6
2-Cy-Cy-Ph1-F
12
12
3-Cy-Cy-Ph1-F
12
10
10
3-Cy-Cy-Ph1-OCFFF
12
12
12
3-Cy-Cy-Ph-OCFFF
12
3-Cy-Ph-Ph1-OCFFF
12
12
12
4-Cy-Cy-Ph1-F
12
12
5-Cy-Cy-Ph1-F
11
11
11
5-Cy-Cy-Ph1-OCFFF
9
9
9
5-Cy-Cy-Ph-OCFFF
10
5-Cy-Ph-Ph1-OCFFF
11
11
11
Sum of composition ratios
100
100
100
Tni/° C.
91.1
83.5
86.8
Δn (20° C.)
0.092
0.089
0.092
Δε (20° C.)
9.9
8.3
7.9
Vsat/V (25° C.)
4.7
5.3
5.6
τr + d/msec (25° C., 6 V)
7.1
7.5
7.9
The liquid crystal display devices of Examples 8 to 10 realized higher response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with conventional TN liquid crystal display devices in which the same liquid crystals having positive dielectric anisotropy were interposed.
Examples 11 to 13
A liquid crystal display device of Example 11 was produced in the same manner as in Example 1 by interposing the liquid crystals having positive dielectric anisotropy indicated in Table 5; a liquid crystal display device of Example 12 was produced in the same manner as in Example 1; and a liquid crystal display device of Example 13 was produced in the same manner as in Example 1.
TABLE 5
Example
Example
Example
11
12
13
5-Cy-2-Ph1-F
5
5-Cy-Ph-F
10
5-Ph1-Ph-OCFFF
8
7-Cy-2-Ph1-F
5
7-Cy-Ph3-F
8
7-Cy-Ph-F
15
7-Ph1-Ph-OCFFF
7
2-Cy-Cy-Ph-OCFFF
13
9
3-Cy-2-Cy-Ph3-F
10
3-Cy-Cy-2-Ph3-F
10
3-Cy-Cy-Ph3-F
12
6
3-Cy-Cy-Ph-OCFFF
15
12
3-Cy-Ph1-Ph-OCFF
7
3-Cy-Ph-CFFO-Ph3-F
5
3-Cy-Ph-CFFO-Ph-OCFFF
5
3-Cy-Ph-Ph1-F
13
3-Cy-Ph-Ph1-OCFF
8
3-Cy-Ph-Ph3-F
9
5
4-Cy-2-Cy-Ph3-F
6
4-Cy-Cy-Ph3-F
3
4-Cy-Cy-Ph-OCFFF
13
5-Cy-2-Cy-Ph3-F
6
5-Cy-Cy-2-Ph3-F
5
5-Cy-Cy-Ph3-F
9
5-Cy-Cy-Ph-OCFFF
14
12
5-Cy-Ph-CFFO-Ph1-F
5
5-Cy-Ph-CFFO-Ph3-F
10
5-Cy-Ph-CFFO-Ph-CF3
5
5-Cy-Ph-Ph3-F
5
3-Cy-Cy-2-Ph-Ph3-F
3
3-Cy-Cy-Ph1-Ph-F
4
3-Cy-Cy-Ph-Ph3-F
3
Sum of composition ratios
100
100
100
Tni/° C.
79.8
65.1
61.7
Δn (20° C.)
0.0876
0.0995
0.0827
Δε (20° C.)
8.7
7.6
7.3
Vsat/V (25° C.)
5.2
5.8
5.4
τr + d/msec (25° C., 6 V)
7.1
6.7
6.2
The liquid crystal display devices of Examples 11 to 13 realized higher response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with conventional TN liquid crystal display devices in which the same liquid crystals having positive dielectric anisotropy were interposed.
Examples 14 to 17
A liquid crystal display device of Example 14 was produced in the same manner as in Example 1 by interposing the liquid crystals having positive dielectric anisotropy indicated in Table 6; a liquid crystal display device of Example 15 was produced in the same manner as in Example 1; a liquid crystal display device of Example 16 was produced in the same manner as in Example 1; and a liquid crystal display device of Example 17 was produced in the same manner as in Example 1 by interposing the liquid crystals having positive dielectric anisotropy indicated in Table 7.
TABLE 6
Example
Example
Example
14
15
16
3-Cy-2-Ph1-C1
5
3-Cy-Ph1-C1
11
5-Cy-2-Ph1-C1
5
5-Cy-Ph1-C1
10
2-Cy-Cy-Ph3-C1
10
3-Cy-Cy-Ph3-C1
9
3-Cy-Cy-Ph-C1
5-Cy-Cy-Ph3-C1
11
5-Cy-Ph-F
11
7
6-Cy-Ph-F
4
7-Cy-Ph-F
13
6
10
2-Cy-Cy-Ph-OCFFF
9
9
9
3-Cy-Cy-Ph-OCFFF
12
11
12
3-Cy-Ph1-Ph-CFFF
5
5
3-Cy-Ph1-Ph-F
10
3-Cy-Ph1-Ph-OCFFF
12
4-Cy-Cy-Ph-OCFFF
7
7
5-Cy-Cy-Ph-OCFFF
12
12
12
5-Cy-Ph1-Ph-CFFF
5
5-Cy-Ph1-Ph-OCFFF
9
5-Cy-Ph-Ph1-F
13
8
2-Cy-Cy-Ph1-Ph-F
3
3-Cy-Cy-Ph1-Ph-F
3
5-Cy-Cy-Ph1-Ph-F
3
Sum of composition ratios
100
100
100
Tni/° C.
65.8
86.2
70.7
Δn (20° C.)
0.0825
0.0923
0.0992
Δε (20° C.)
7.5
6.2
6.9
Vsat/V (25° C.)
5.2
6.1
4.7
τr + d/msec (25° C., 6 V)
7.3
6.9
7.2
TABLE 7
Example 17
3-Cy-Cy-Ph-C1
4
5-Cy-Cy-Ph-C1
4
2-Cy-Ph-Ph1-F
3
2-Cy-Ph-Ph-F
3
3-Cy-2-Cy-Ph3-F
6
3-Cy-Cy-2-Ph3-F
12
3-Cy-Cy-Ph3-F
3
3-Cy-Ph-CFFO-Ph-OCFFF
5
3-Cy-Ph-Ph1-F
3
3-Cy-Ph-Ph3-F
6
3-Cy-Ph-Ph-F
3
4-Cy-2-Cy-Ph3-F
6
4-Cy-Cy-Ph3-F
3
5-Cy-2-Cy-Ph3-F
6
5-Cy-Cy-2-Ph3-F
6
5-Cy-Ph-CFFO-Ph3-F
10
5-Cy-Ph-CFFO-Ph-CF3
5
5-Cy-Ph-Ph1-F
6
5-Cy-Ph-Ph3-F
6
Sum of composition ratios
100
Tni/° C.
82.4
Δn (20° C.)
0.0998
Δε (20° C.)
10.9
Vsat/V (25° C.)
4.3
τr + d/msec (25° C., 6 V)
7.1
The liquid crystal display devices realized higher response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with conventional TN liquid crystal display devices in which the same liquid crystals having positive dielectric anisotropy were interposed.
Examples 18 to 21
A liquid crystal display device of Example 18 was produced in the same manner as in Example 1 by interposing the liquid crystals having positive dielectric anisotropy indicated in Table 8; a liquid crystal display device of Example 19 was produced in the same manner as in Example 1; a liquid crystal display device of Example 20 was produced in the same manner as in Example 1; and a liquid crystal display device of Example 21 was produced in the same manner as in Example 1 except that d cell : 3.0 μm, d ITO =10 μm, d gap =10 μm.
TABLE 8
Example
Example
Example
Example
18
19
20
21
3-Cy-Ph-C1
4
5-Cy-Ph-C1
4
7-Cy-Ph-C1
5
2-Cy-Cy-Ph-C1
6
3-Cy-2-Cy-Ph1-C1
3
3-Cy-Cy-Ph-C1
7
5-Cy-Cy-Ph-C1
6
3-Cy-Ph-OCFFF
4
4
3-Ph-Ph-OCFFF
8
4-Cy-Ph-OCFFF
6
6
5-Cy-Ph-OCFFF
7
7
5-Ph-Ph-OCFFF
13
7-Ph-Ph-OCFFF
13
2-Cy-Cy-Ph-OCFFF
8
2-Cy-Ph-Ph1-F
8
8
6
3-Cy-Cy-Ph-OCFFF
13
3-Cy-Ph1-Ph-CFFF
9
3-Cy-Ph1-Ph-F
12
12
3-Cy-Ph1-Ph-OCFFF
9
3-Cy-Ph-CFFO-Ph3-F
5
3-Cy-Ph-CFFO-Ph-
5
OCFFF
3-Cy-Ph-Ph1-F
14
6
3-Cy-Ph-Ph3-F
12
12
13
4-Cy-Cy-Ph-OCFFF
5
4-Cy-Ph-Ph3-F
10
10
5-Cy-Cy-Ph-OCFFF
12
5-Cy-Ph1-Ph-CFFF
11
5-Cy-Ph1-Ph-OCFFF
11
5-Cy-Ph-Ph1-F
10
10
14
12
5-Cy-Ph-Ph3-F
11
11
13
3-Cy-Ph1-T-Ph-2
3
3-Cy-Ph1-V-Ph-2
2
Sum of composition
100
100
100
100
ratios
Tni/° C.
65.9
61.7
65.6
89.1
Δn (20° C.)
0.1116
0.1155
0.117
0.1274
Δε (20° C.)
5.9
7.3
10.5
6.2
Vsat/V (25° C.)
6.8
9.8
6.8
10.1
τr + d/msec (25° C.,
4.6
4.4
4.3
4.1
6 V)
The liquid crystal display devices realized higher response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with conventional TN liquid crystal display devices in which the same liquid crystals having positive dielectric anisotropy were interposed.
Examples 22 and 23
A liquid crystal display device of Example 22 was produced in the same manner as in Example 1 by interposing the liquid crystals having positive dielectric anisotropy indicated in Table 9; and a liquid crystal display device of Example 23 was produced in the same manner as in Example 1 except that d cell : 3.5 μm, d ITO =10 μm, d gap =10 μm.
TABLE 9
Example
Example
22
23
5-Cy-Ph-F
6
5
7-Cy-Ph-F
6
6
2-Cy-Ph-Ph1-F
8
3-Cy-2-Cy-Ph-OCFFF
8
3-Cy-Cy-2-Ph-OCFFF
8
3-Cy-Cy-Ph1-OCFFF
12
3-Cy-Cy-Ph-OCFFF
12
3-Cy-Ph-CFFO-Ph3-F
3
3-Cy-Ph-CFFO-Ph-OCFFF
5
3-Cy-Ph-Ph1-F
8
12
3-Cy-Ph-Ph1-OCFFF
12
5-Cy-2-Cy-Ph-OCFFF
8
5-Cy-Cy-2-Ph-OCFFF
8
5-Cy-Cy-Ph1-OCFFF
9
5-Cy-Cy-Ph-OCFFF
8
10
5-Cy-Ph-CFFO-Ph3-F
8
5-Cy-Ph-Ph1-F
16
11
5-Cy-Ph-Ph1-OCFFF
11
Sum of composition ratios
100
100
Tni/° C.
84.5
89.3
Δn (20° C.)
0.1004
0.105
Δε (20° C.)
6.3
9.7
Vsat/V (25° C.)
7.6
6.9
τr + d/msec (25° C., 6 V)
6.9
6.4
The liquid crystal display devices of Examples 22 and 23 realized higher response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with conventional TN liquid crystal display devices in which the same liquid crystals having positive dielectric anisotropy were interposed.
Examples 24 and 25
A liquid crystal display device of Example 24 was produced in the same manner as in Example 1 by interposing the liquid crystals having positive dielectric anisotropy indicated in Table 10; and a liquid crystal display device of Example 25 was produced in the same manner as in Example 1.
TABLE 10
Example
Example
24
25
3-Ph1-Ph-C1
6
5-Ph1-Ph-C1
7
2-Cy-Ph-Ph3-C1
5
5
3-Cy-Ph-Ph3-C1
9
9
5-Cy-Ph-Ph3-C1
11
11
3-Ph-Ph1-F
6
5-Ph-Ph1-F
7
2-Cy-Ph-Ph1-F
8
8
3-Cy-2-Ph-Ph1-F
11
11
3-Cy-Ph-Ph1-F
12
12
4-Cy-2-Ph-Ph1-F
10
10
5-Cy-2-Ph-Ph1-F
11
11
5-Cy-Ph-Ph1-F
10
10
Sum of composition ratios
100
100
Tni/° C.
85.3
83.1
Δn (20° C.)
0.1474
0.1582
Δε (20° C.)
5.9
5.4
Vsat/V (25° C.)
13.8
14.7
τr + d/msec (25° C., 6 V)
3.2
3.5
The liquid crystal display devices of Examples 24 and 25 realized higher response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with conventional TN liquid crystal display devices in which the same liquid crystals having positive dielectric anisotropy were interposed.
Examples 26 to 28
The liquid crystal compositions having positive dielectric anisotropy used in Example 5, 12 and 17 were each interposed in a cell with d ITO =4 μm and d gap =4 μm, and thus liquid crystal display devices of Examples 26 to 28 were produced. Their response speeds were measured, and the following results were obtained.
Example 26: τr+d=1.6 msec (liquid crystal composition of Example 5)
Example 27: τr+d=1.3 msec (liquid crystal composition of Example 12)
Example 28: τr+d=0.9 msec (liquid crystal composition of Example 17)
The liquid crystal display devices of Examples 26 to 28 exhibited characteristics of very fast responses. Furthermore, a pressing pressure was applied to the liquid crystal display devices produced in these Examples, but the light leakage that occurs in conventional VA displays was hardly observed.
Examples 29 to 32
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the respective surfaces that faced each other. The liquid crystals having positive dielectric anisotropy indicated in Table 11 were interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300).
TABLE 11
Example
Example
Example
Example
29
30
31
32
5-Cy-Ph-F
5
7-Cy-Ph3-F
10
7-Cy-Ph-F
6
2-Cy-Cy-Ph1-OCFF
8
2-Cy-Cy-Ph-OCFFF
15
3-Cy-Cy-2-Ph3-F
7
3-Cy-Cy-Ph1-F
10
3-Cy-Cy-Ph3-F
16
12
12
3-Cy-Cy-Ph3-OCFFF
12
3-Cy-Cy-Ph-OCFFF
10
18
3-Cy-Ph-Ph1-F
18
3-Cy-Ph-Ph1-OCFFF
15
10
3-Cy-Ph-Ph3-F
15
4-Cy-Cy-Ph3-F
13
4-Cy-Cy-Ph-OCFFF
10
12
4-Cy-Ph-Ph3-F
12
5-Cy-Cy-Ph1-F
10
5-Cy-Cy-Ph1-OCFFF
9
5-Cy-Cy-Ph3-F
12
5
9
5-Cy-Cy-Ph-OCFFF
10
14
12
5-Cy-Ph-Ph1-F
14
5-Cy-Ph-Ph1-OCFFF
11
5-Cy-Ph-Ph3-F
11
2-Ph-T-Ph-1
5
5
5
5
2-Ph-T-Ph-O1
5
3-Cy-Cy-4
6
3-Cy-Ph1-Ph-Cy-3
6
Sum of composition
100
100
100
100
ratios
Tni/° C.
91.9
86.1
79.1
65.3
Δn (20° C.)
0.1090
0.114
0.101
0.1161
Δε (20° C.)
11.4
10.4
10.1
10.4
K3/K1 (20° C.)
1.33
1.30
1.29
1.32
K3/pN (20° C.)
14.9
14.8
14.3
15.1
K1/pN (20° C.)
11.2
11.4
11.1
11.4
Vsat/V (25° C.)
8.9
9.6
10.1
10.3
τr + d/msec (25° C.)
1.23
1.16
1.08
1.10
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 29 to 32 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which conventional liquid crystals having positive dielectric anisotropy were interposed.
Comparative Example 3
A liquid crystal panel of Comparative Example 3 was produced in the same manner as in Example 29 by interposing the liquid crystals having positive dielectric anisotropy indicated in Table 12, and the property values were measured. The results are presented in Table 12.
TABLE 12
Comparative
Example 3
5-Cy-Ph-F
5
7-Cy-Ph-F
6
2-Cy-Cy-Ph-OCFFF
11
3-Cy-Cy-Ph1-OCFFF
12
3-Cy-Cy-Ph-OCFFF
12
4-Cy-Cy-Ph-OCFFF
10
5-Cy-Cy-Ph3-F
9
5-Cy-Cy-Ph-OCFFF
12
3-Ph-VO-Ph1-CN
11
3-Cy-Cy-Ph3-CN
8
3-Cy-Oc-Ph3-F
4
Sum of composition ratios
100
Tni/° C.
92.1
Δn (20° C.)
0.094
Δε (20° C.)
11.7
Vsat/V (25° C.)
5.6
τr + d/msec (25° C., 6 V)
3.7
The liquid crystal panel of Comparative Example 3 in which liquid crystals having positive dielectric anisotropy were interposed, exhibited a slow response speed, a slightly smaller amount of light transmission, and particularly poor retention ratio and long-term reliability as compared with the liquid crystal panels of the invention.
Examples 33 to 35
The liquid crystals having positive dielectric anisotropy indicated in Table 13 were interposed between a first substrate and a second substrate in the same manner as in Example 29 and Comparative Example 3, and thus liquid crystal panels were produced.
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 33 to 35 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which conventional liquid crystals having positive dielectric anisotropy were interposed.
TABLE 13
Example
Example
Example
33
34
35
5-Cy-Ph-F
5
5
5-Ph-Ph1-F
5
7-Cy-Ph-F
6
6
7-Ph1-Ph-OCFFF
6
2-Cy-Cy-Ph-OCFFF
11
11
11
3-Cy-Cy-Ph1-F
12
3-Cy-Cy-Ph3-OCFFF
12
3-Cy-Cy-Ph-OCFFF
12
12
10
3-Cy-Ph-Ph1-F
14
4-Cy-Cy-Ph-OCFFF
10
10
10
5-Cy-Cy-Ph1-OCFFF
9
5-Cy-Cy-Ph-OCFFF
12
12
6
5-Cy-Ph-Ph1-F
11
5-Cy-Ph-Ph1-OCFFF
11
11
3-Ph-Ph-Ph3-F
11
11
6
3-Ph-Ph1-Ph3-F
10
5
5-Ph-Ph1-Ph3-F
10
5-Ph-Ph3-Ph1-F
5
5-Cy-Ph1-Ph-Cy-3
2
Sum of composition ratios
100
100
100
Tni/° C.
92.8
98.9
96.4
Δn (20°)
0.1193
0.1204
0.1086
Δε (20° C.)
12.6
13.1
10.1
K3/K1 (20° C.)
1.52
1.56
1.40
K3/pN (20° C.)
17.3
17.6
15.8
K1/pN (20° C.)
11.4
11.3
11.3
Vsat/V (25° C.)
6.7
6.1
9.9
τr + d/msec (25° C.)
1.14
1.03
1.07
Examples 36 to 38
The liquid crystals having positive dielectric anisotropy indicated in Table 14 were interposed between a first substrate and a second substrate in the same manner as in Example 29 and Comparative Example 3, and thus liquid crystal panels were produced.
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 36 to 38 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which conventional liquid crystals having positive dielectric anisotropy were interposed.
TABLE 14
Example
Example
Example
36
37
38
5-Ph1-Ph-OCFFF
5
5-Ph-Ph1-F
5
10
5-Ph-Ph-OCFFF
5
7-Cy-2-Ph1-F
5
7-Ph1-Ph-OCFFF
6
15
7-Ph-Ph-OCFFF
6
3-Cy-Cy-Ph1-F
12
10
3-Cy-Cy-Ph1-OCFFF
12
12
3-Cy-Cy-Ph-OCFFF
12
3-Cy-Ph1-Ph-OCFF
7
3-Cy-Ph-Ph1-F
13
3-Cy-Ph-Ph1-OCFF
8
3-Cy-Ph-Ph1-OCFFF
12
12
5-Cy-Cy-Ph1-F
11
11
5-Cy-Cy-Ph1-OCFFF
9
9
5-Cy-Ph-Ph1-OCFFF
11
11
3-Ph-Ph-Ph3-F
9
3-Ph-Ph1-Ph3-F
12
12
3-Ph-Ph3-Ph1-F
12
5-Ph-Ph3-Ph1-F
10
12
3-Cy-Cy-Ph1-Ph-F
4
Sum of composition ratios
100
100
100
Tni/° C.
91.1
83.5
61.3
Δn (20° C.)
0.1118
0.1102
0.1325
Δε (20° C.)
11.7
10.9
15.7
K3/K1 (20° C.)
1.37
1.38
1.38
K3/pN (20° C.)
14.9
14.9
15.3
K1/pN (20° C.)
10.9
10.8
11.1
Vsat/V (25° C.)
8.4
9.3
5.4
τr + d/msec (25° C.)
1.13
1.12
0.95
Example 39
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the other sides of the respective surfaces that faced each other, and an alignment film of horizontal orientation was formed on each of the reverse sides. The liquid crystals having positive dielectric anisotropy disclosed in Examples 29 to 38 and Comparative Example 3 were respectively interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300, AL-1051).
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 29 to 38 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Example 3 were interposed.
Example 40
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the respective surfaces that faced each other. Compositions obtained by adding 0.3% by mass of 2-methyl-acrylic acid 4′-{2-[4-(2-acryloyloxyethyl)phenoxycarbonyl]ethyl}biphenyl-4-yl ester to the liquid crystals having positive dielectric anisotropy as indicated in Examples 29 to 38 and Comparative Example 3 were interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300). While a driving voltage was applied between the electrodes, the liquid crystal panels were irradiated with ultraviolet radiation for 600 seconds (3.0 J/cm 2 ), and thus a polymerization treatment was carried out.
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 29 to 38 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Example 3 were interposed.
Example 41
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the other sides of the respective surfaces that faced each other, and an alignment film of horizontal orientation was formed on each of the reverse sides. Each of the compositions obtained by adding 0.3% by mass of 2-methyl-acrylic acid 4′-{2-[4-(2-acryloyloxyethyl)phenoxycarbonyl]ethyl}biphenyl-4-yl ester to the liquid crystals having positive dielectric anisotropy as indicated in Examples 29 to 38 and Comparative Example 3 was interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300, AL-1051). While a driving voltage was applied between the electrodes, the liquid crystal panels were irradiated with ultraviolet radiation for 600 seconds (3.0 J/cm 2 ), and thus a polymerization treatment was carried out.
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 29 to 38 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Example 1 were interposed.
Examples 42 to 45
An electrode structure as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the respective surfaces that faced each other. The liquid crystals having positive dielectric anisotropy indicated in Table 15 were respectively interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300).
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 42 to 45 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which conventional liquid crystals having positive dielectric anisotropy were interposed.
TABLE 15
Example
Example
Example
Example
42
43
44
45
3-Ph-Ph-OCFFF
8
5-Cy-Ph-F
5
5-Ph1-Ph-OCFFF
8
5-Ph-Ph-OCFFF
13
7-Cy-Ph3-F
8
7-Cy-Ph-F
6
7-Ph1-Ph-OCFFF
8
7-Ph-Ph-OCFFF
13
2-Cy-Cy-Ph-OCFFF
11
8
3-Cy-Cy-Ph1-F
10
3-Cy-Cy-Ph3-F
12
16
3-Cy-Cy-Ph3-OCFFF
12
3-Cy-Cy-Ph-OCFFF
12
13
3-Cy-Ph-Ph1-F
14
3-Cy-Ph-Ph1-OCFFF
12
10
3-Cy-Ph-Ph3-F
15
4-Cy-Cy-Ph3-F
6
4-Cy-Cy-Ph-OCFFF
10
5
4-Cy-Ph-Ph3-F
12
5-Cy-Cy-Ph1-F
8
5-Cy-Cy-Ph1-OCFFF
7
5-Cy-Cy-Ph3-F
9
5-Cy-Cy-Ph-OCFFF
14
12
5-Cy-Ph-Ph1-F
14
5-Cy-Ph-Ph1-OCFFF
11
3-Ph-Ph-Ph3-F
10
10
3-Ph-Ph1-Ph3-F
10
10
3-Ph-Ph3-Ph1-F
6
10
3-Cy-Cy-4
6
5
3-Cy-Cy-5
5
3-Cy-Ph1-Ph-Cy-3
6
Sum of composition
100
100
100
100
ratios
Tni/° C.
91.6
85.7
78.4
65.6
Δn (20° C.)
0.1100
0.113
0.101
0.1168
Δε (20° C.)
11.6
10.3
10.2
10.5
K3/K1 (20° C.)
1.39
1.39
1.36
1.43
K3/pN (20° C.)
15.7
16.1
15.2
16.5
K1/pN (20° C.)
11.3
11.6
11.2
11.5
Vsat/V (25° C.)
8.7
9.5
9.8
10.5
τr + d/msec (25° C.)
1.23
1.17
1.06
1.10
Examples 46 to 48
The liquid crystals having positive dielectric anisotropy indicated in Table 16 were interposed between a first substrate and a second substrate in the same manner as in Example 42, and thus liquid crystal panels were produced.
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 46 to 48 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which conventional liquid crystals having positive dielectric anisotropy were interposed.
TABLE 16
Example
Example
Example
46
47
48
5-Cy-Ph-F
5
5
5-Ph-Ph1-F
5
7-Cy-Ph-F
6
6
7-Ph1-Ph-OCFFF
6
2-Cy-Cy-Ph-OCFFF
11
11
11
3-Cy-Cy-Ph1-F
12
3-Cy-Cy-Ph3-OCFFF
12
3-Cy-Cy-Ph-OCFFF
12
12
10
3-Cy-Ph-Ph1-F
14
4-Cy-Cy-Ph-OCFFF
10
10
10
5-Cy-Cy-Ph1-OCFFF
9
5-Cy-Cy-Ph-OCFFF
12
12
6
5-Cy-Ph-Ph1-F
11
5-Cy-Ph-Ph1-OCFFF
11
11
3-Ph-Ph-Ph3-F
11
11
6
3-Ph-Ph1-Ph3-F
10
5
5-Ph-Ph1-Ph3-F
10
5-Ph-Ph3-Ph1-F
5
5-Cy-Ph1-Ph-Cy-3
2
Sum of composition ratios
100
100
100
Tni/° C.
92.8
98.9
96.4
Δn (20° C.)
0.1193
0.1204
0.1086
Δε (20° C.)
12.6
13.1
10.1
K3/K1 (20°)
1.52
1.56
1.40
K3/pN (20° C.)
17.3
17.6
15.8
K1/pN (20° C.)
11.4
11.3
11.3
Vsat/V (25° C.)
6.7
6.1
9.9
τr + d/msec (25° C.)
1.14
1.03
1.07
Examples 49 to 51
The liquid crystals having positive dielectric anisotropy indicated in Table 17 were interposed between a first substrate and a second substrate in the same manner as in Example 42, and thus liquid crystal panels were produced.
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 49 to 51 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which conventional liquid crystals having positive dielectric anisotropy were interposed.
TABLE 17
Example
Example
Example
49
50
51
5-Ph1-Ph-OCFFF
5
5-Ph-Ph1-F
5
10
5-Ph-Ph-OCFFF
5
7-Cy-2-Ph1-F
5
7-Ph1-Ph-OCFFF
6
15
7-Ph-Ph-OCFFF
6
3-Cy-Cy-Ph1-F
12
10
3-Cy-Cy-Ph1-OCFFF
12
12
3-Cy-Cy-Ph-OCFFF
12
3-Cy-Ph1-Ph-OCFF
7
3-Cy-Ph-Ph1-F
13
3-Cy-Ph-Ph1-OCFF
8
3-Cy-Ph-Ph1-OCFFF
12
12
5-Cy-Cy-Ph1-F
11
11
5-Cy-Cy-Ph1-OCFFF
9
9
5-Cy-Ph-Ph1-OCFFF
11
11
3-Ph-Ph-Ph3-F
9
3-Ph-Ph1-Ph3-F
12
12
3-Ph-Ph3-Ph1-F
12
5-Ph-Ph3-Ph1-F
10
12
3-Cy-Cy-Ph1-Ph-F
4
Sum of composition ratios
100
100
100
Tni/° C.
91.1
83.5
61.3
Δn (20°)
0.1118
0.1102
0.1325
Δε (20° C.)
11.7
10.9
15.7
K3/K1 (20°)
1.37
1.38
1.38
K3/pN (20° C.)
14.9
14.9
15.3
K1/pN (20° C.)
10.9
10.8
11.1
Vsat/V (25° C.)
8.4
9.3
5.4
τr + d/msec (25° C.)
1.13
1.12
0.95
Example 52
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the other sides of the respective surfaces that faced each other, and an alignment film of horizontal orientation was formed on each of the reverse sides. The liquid crystals having positive dielectric anisotropy disclosed in Examples 42 to 51 and Comparative Examples 1 to 3 were respectively interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300, AL-1051).
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 42 to 51 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Examples 1 to 3 were interposed.
Example 53
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the respective surfaces that faced each other. Compositions obtained by adding 0.3% by mass of 2-methyl-acrylic acid 4′-{2-[4-(2-acryloyloxyethyl)phenoxycarbonyl]ethyl}biphenyl-4-yl ester to the liquid crystals having positive dielectric anisotropy as indicated in Examples 42 to 51 and Comparative Examples 1 to 3 were interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300). While a driving voltage was applied between the electrodes, the liquid crystal panels were irradiated with ultraviolet radiation for 600 seconds (3.0 J/cm 2 ), and thus a polymerization treatment was carried out.
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 42 to 51 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Examples 1 to 3 were interposed.
Example 54
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the other sides of the respective surfaces that faced each other, and an alignment film of horizontal orientation was formed on each of the reverse sides. Each of the compositions obtained by adding 0.3% by mass of 2-methyl-acrylic acid 4′-{2-[4-(2-acryloyloxyethyl)phenoxycarbonyl]ethyl}biphenyl-4-yl ester to the liquid crystals having positive dielectric anisotropy as indicated in Examples 42 to 51 and Comparative Examples 1 to 3 was interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300, AL-1051). While a driving voltage was applied between the electrodes, the liquid crystal panels were irradiated with ultraviolet radiation for 600 seconds (3.0 J/cm 2 ), and thus a polymerization treatment was carried out.
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 42 to 51 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Examples 1 to 3 were interposed.
Examples 55 to 57
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the respective surfaces that faced each other. The liquid crystals having positive dielectric anisotropy indicated in Table 18 were interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300).
TABLE 18
Example
Example
Example
55
56
57
3-Ph-T-Ph1-F
5
5-Cy-Ph-F
5
7-Cy-Ph3-F
9
7-Cy-Ph-F
6
2-Cy-Cy-Ph1-OCFFF
8
3-Cy-Cy-2-Ph3-F
7
3-Cy-Cy-Ph1-F
9
3-Cy-Cy-Ph3-F
16
11
12
3-Cy-Cy-Ph3-OCFFF
12
3-Cy-Cy-Ph-OCFFF
10
3-Cy-Ph-T-Ph3-F
10
3-Cy-Ph-T-Ph1-OCFFF
15
9
5
4-Cy-Cy-Ph3-F
11
12
4-Cy-Cy-Ph-OCFFF
10
4-Cy-Ph-Ph3-F
12
5-Cy-Cy-Ph1-F
10
5-Cy-Cy-Ph1-OCFFF
9
5-Cy-Cy-Ph3-F
12
5
9
5-Cy-Cy-Ph-OCFFF
10
14
5-Cy-Ph-Ph1-OCFFF
11
3-Cy-Cy-4
5
3-Cy-Cy-5
5
5
5
3-Cy-Ph1-Ph-Cy-3
6
Sum of composition ratios
100
100
100
Tni/° C.
92.3
86.4
80.3
Δn (20°)
0.1076
0.112
0.108
Δε (20° C.)
11.7
10.9
11.2
K3/K1 (20°)
1.32
1.39
1.35
K3/pN (20° C.)
14.8
15.1
14.6
K1/pN (20° C.)
11.2
10.9
10.8
Vth/V (25° C.)
4.3
5.1
4.9
τr + d/msec (25° C.)
1.28
0.95
1.38
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 55 to 57 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which conventional liquid crystals having positive dielectric anisotropy were interposed.
Comparative Example 4
A liquid crystal panel of Comparative Example 4 was produced in the same manner as in Example 55 by interposing the liquid crystals having positive dielectric anisotropy indicated in Table 19, and the property values were measured. The results are presented in Table 19.
TABLE 19
Comparative
Example 4
5-Cy-Ph-F
5
7-Cy-Ph-F
6
2-Cy-Cy-Ph-OCFFF
11
3-Cy-Cy-Ph1-OCFFF
12
3-Cy-Cy-Ph-OCFFF
12
4-Cy-Cy-Ph-OCFFF
10
5-Cy-Cy-Ph3-F
9
5-Cy-Cy-Ph-OCFFF
12
3-Ph-VO-Ph1-CN
11
3-Cy-Cy-Ph3-CN
8
3-Cy-Oc-Ph3-F
4
Sum of composition ratios
100
Tni/° C.
92.1
Δn (20°)
0.094
Δε (20° C.)
11.7
Vsat/V (25° C.)
5.6
τr + d/msec (25° C., 6 V)
3.7
The liquid crystal panel of Comparative Example 4 in which liquid crystals having positive dielectric anisotropy were interposed, exhibited a slow response speed, a slightly smaller amount of light transmission, and particularly poor retention ratio and long-term reliability as compared with the liquid crystal panels of the invention.
Examples 58 and 59
The liquid crystals having positive dielectric anisotropy indicated in Table 20 were interposed between a first substrate and a second substrate in the same manner as in Example 55 and Comparative Example 4, and thus liquid crystal panels were produced.
TABLE 20
Example
Example
58
59
3-Ph-T-Ph1-F
5
7-Cy-Ph-F
6
2-Cy-Cy-Ph-OCFFF
15
11
3-Cy-Cy-Ph1-F
12
3-Cy-Cy-Ph3-F
10
3-Cy-Cy-Ph3-OCFFF
11
3-Cy-Cy-Ph-OCFFF
18
12
3-Cy-Ph-T-Ph3-F
10
11
3-Cy-Ph-T-Ph1-OCFFF
8
4-Cy-Cy-Ph-OCFFF
12
10
5-Cy-Cy-Ph3-OCFFF
14
5-Cy-Cy-Ph-OCFFF
12
12
3-Cy-Cy-4
6
3-Cy-Cy-5
5
Sum of composition ratios
100
100
Tni/° C.
65.3
93.1
Δn (20° C.)
0.1187
0.1213
Δε (20° C.)
11.6
12.8
K3/K1 (20° C.)
1.29
13.31
K3/pN (20° C.)
13.7
14.3
K1/pN (20° C.)
10.6
10.9
Vth/V (25° C.)
6.4
4.4
τr + d/msec (25° C.)
1.42
1.22
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 58 and 59 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which conventional liquid crystals having positive dielectric anisotropy were interposed.
Example 60
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the other sides of the respective surfaces that faced each other, and an alignment film of horizontal orientation was formed on each of the reverse sides. The liquid crystals having positive dielectric anisotropy disclosed in Examples 55 to 59 and Comparative Example 4 were respectively interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300, AL-1051).
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 55 to 59 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Example 4 were interposed.
Example 61
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the respective surfaces that faced each other. Compositions obtained by adding 0.3% by mass of 2-methyl-acrylic acid 4′-{2-[4-(2-acryloyloxyethyl)phenoxycarbonyl]ethyl}biphenyl-4-yl ester to the liquid crystals having positive dielectric anisotropy as indicated in Examples 55 to 59 and Comparative Example 4 were interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300). While a driving voltage was applied between the electrodes, the liquid crystal panels were irradiated with ultraviolet radiation for 600 seconds (3.0 J/cm 2 ), and thus a polymerization treatment was carried out.
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 55 to 59 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Example 4 were interposed.
Example 62
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the other sides of the respective surfaces that faced each other, and an alignment film of horizontal orientation was formed on each of the reverse sides. Each of the compositions obtained by adding 0.3% by mass of 2-methyl-acrylic acid 4′-{2-[4-(2-acryloyloxyethyl)phenoxycarbonyl]ethyl}biphenyl-4-yl ester to the liquid crystals having positive dielectric anisotropy as indicated in Examples 55 to 59 and Comparative Example 4 was interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300, AL-1051). While a driving voltage was applied between the electrodes, the liquid crystal panels were irradiated with ultraviolet radiation for 600 seconds (3.0 J/cm 2 ), and thus a polymerization treatment was carried out.
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 55 to 59 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Example 4 were interposed.
Examples 63 to 65
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the respective surfaces that faced each other. The liquid crystals having positive dielectric anisotropy indicated in Table 21 were interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300).
TABLE 21
Example
Example
Example
63
64
65
7-Cy-Ph3-F
10
2-Cy-Cy-Ph1-OCFF
8
3-Cy-Cy-2-Ph3-F
7
3-Cy-Cy-Ph3-F
11
12
12
3-Cy-Cy-Ph3-OCFFF
12
3-Cy-Ph-Ph1-OCFFF
10
3-Cy-Ph-Ph3-F
15
10
15
4-Cy-Cy-Ph3-F
13
4-Cy-Cy-Ph-OCFFF
5
4-Cy-Ph-Ph3-F
10
12
5-Cy-Cy-Ph1-OCFFF
9
5-Cy-Cy-Ph3-F
12
10
9
5-Cy-Cy-Ph-OCFFF
10
4
5-Cy-Ph-Ph1-OCFFF
11
5-Cy-Ph-Ph3-F
11
5
10
0d1-Cy-Cy-5
11
0d3-Cy-Cy-3
10
1d1-Cy-Cy-5
5
0d1-Cy-Cy-Ph-1
5
10
0d3-Cy-Cy-Ph-1
6
Sum of composition ratios
100
100
100
Tni/° C.
90.8
85.3
80.6
Δn (20° C.)
0.1063
0.1097
0.1014
Δε (20° C.)
11.2
10.6
10.0
K3/K1 (20° C.)
1.34
1.36
1.40
K3/pN (20° C.)
15.1
14.8
14.7
K1/pN (20° C.)
11.3
10.9
10.5
Vth/V (25° C.)
4.7
5.1
5.4
τr + d/msec (25° C.)
1.23
1.18
1.15
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 63 to 65 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which conventional liquid crystals having positive dielectric anisotropy were interposed.
Comparative Example 5
A liquid crystal panel of Comparative Example 5 was produced in the same manner as in Example 63 by interposing the liquid crystals having positive dielectric anisotropy indicated in Table 22, and the property values were measured. The results are presented in Table 22.
TABLE 22
Comparative
Example 5
5-Cy-Ph-F
5
7-Cy-Ph-F
6
2-Cy-Cy-Ph-OCFFF
11
3-Cy-Cy-Ph1-OCFFF
12
3-Cy-Cy-Ph-OCFFF
12
4-Cy-Cy-Ph-OCFFF
10
5-Cy-Cy-Ph3-F
9
5-Cy-Cy-Ph-OCFFF
12
3-Ph-VO-Ph1-CN
11
3-Cy-Cy-Ph3-CN
8
3-Cy-Oc-Ph3-F
4
Sum of composition ratios
100
Tni/° C.
92.1
Δn (20°)
0.094
Δε (20° C.)
11.7
Vsat/V (25° C.)
5.6
τr + d/msec (25° C., 6 V)
3.7
The liquid crystal panel of Comparative Example 5 in which liquid crystals having positive dielectric anisotropy were interposed, exhibited a slow response speed, a slightly smaller amount of light transmission, and particularly poor retention ratio and long-term reliability as compared with the liquid crystal panels of the invention.
Examples 66 and 67
The liquid crystals having positive dielectric anisotropy indicated in Table 23 were interposed between a first substrate and a second substrate in the same manner as in Example 63 and Comparative Example 5, and thus liquid crystal panels were produced.
TABLE 23
Example
Example
66
67
5-Cy-Ph-F
5
7-Cy-Ph-F
6
2-Cy-Cy-Ph-OCFFF
15
11
3-Cy-Cy-Ph1-F
12
3-Cy-Cy-Ph-OCFFF
18
12
3-Cy-Ph-Ph1-F
18
4-Cy-Cy-Ph-OCFFF
10
5-Cy-Cy-Ph3-OCFFF
10
12
5-Cy-Ph-Ph1-F
14
5-Cy-Ph-Ph1-OCFFF
11
3-Ph-Ph-Ph3-F
11
3-Ph-Ph1-Ph3-F
10
0d1-Cy-Cy-5
11
0d1-Cy-Cy-Ph-1
7
0d1-Cy-Cy-Ph-Ph-1
4
0d3-Cy-Cy-Ph-Ph-1
3
Sum of composition ratios
100
100
Tni/° C.
68.2
93.1
Δn (20° C.)
0.1154
0.1195
Δε (20° C.)
10.1
12.7
K3/K1 (20° C.)
1.35
1.41
K3/pN (20° C.)
15.4
15.8
K1/pN (20° C.)
11.4
11.2
Vth/V (25° C.)
6.4
4.1
τr + d/msec (25° C.)
0.93
1.12
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 66 and 67 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which conventional liquid crystals having positive dielectric anisotropy were interposed.
Example 68
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the other sides of the respective surfaces that faced each other, and an alignment film of horizontal orientation was formed on each of the reverse sides. The liquid crystals having positive dielectric anisotropy disclosed in Examples 63 to 67 and Comparative Example 5 were respectively interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300, AL-1051).
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 63 to 67 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Example 5 were interposed.
Example 69
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the respective surfaces that faced each other. Compositions obtained by adding 0.3% by mass of 2-methyl-acrylic acid 4′-{2-[4-(2-acryloyloxyethyl)phenoxycarbonyl]ethyl}biphenyl-4-yl ester to the liquid crystals having positive dielectric anisotropy as indicated in Examples 63 to 67 and Comparative Example 5 were interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300). While a driving voltage was applied between the electrodes, the liquid crystal panels were irradiated with ultraviolet radiation for 600 seconds (3.0 J/cm 2 ), and thus a polymerization treatment was carried out.
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 63 to 67 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Example 5 were interposed.
Example 70
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the other sides of the respective surfaces that faced each other, and an alignment film of horizontal orientation was formed on each of the reverse sides. Each of the compositions obtained by adding 0.3% by mass of 2-methyl-acrylic acid 4′-{2-[4-(2-acryloyloxyethyl)phenoxycarbonyl]ethyl}biphenyl-4-yl ester to the liquid crystals having positive dielectric anisotropy as indicated in Examples 63 to 67 and Comparative Example 5 was interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300, AL-1051). While a driving voltage was applied between the electrodes, the liquid crystal panels were irradiated with ultraviolet radiation for 600 seconds (3.0 J/cm 2 ), and thus a polymerization treatment was carried out.
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 63 to 67 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Example 5 were interposed.
Examples 71 to 73
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the respective surfaces that faced each other. The liquid crystals having positive dielectric anisotropy indicated in Table 24 were interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300).
TABLE 24
Example
Example
Example
71
72
73
7-Cy-Ph3-F
5
2-Cy-Cy-Ph1-OCFF
8
3-Cy-2-Cy-Ph3-F
5
3-Cy-Cy-2-Ph3-F
7
3-Cy-Cy-Ph3-F
13
12
12
3-Cy-Cy-Ph3-OCFF
13
5
12
3-Cy-Ph-Ph3-F
10
12
4-Cy-Cy-Ph3-F
11
13
7
4-Cy-Cy-Ph-OCFFF
5
4-Cy-Ph-Ph3-F
10
8
5-Cy-Cy-2-Ph3-F
5
5-Cy-Cy-Ph1-F
11
5-Cy-Cy-Ph1-OCFFF
9
10
5-Cy-Cy-Ph3-F
12
10
9
5-Cy-Cy-Ph-OCFFF
10
4
5-Cy-Ph-Ph3-F
5
1-Ph-T-Ph-6
5
2-Ph-T-Ph-1
6
2-Ph-T-Ph-O1
5
3-Ph-T-Ph-O1
5
4-Ph-T-Ph-O1
3
5-Ph-T-Ph-O1
5
3-Cy-Ph1-T-Ph-2
5
7
6
Sum of composition ratios
100
100
100
Tni/° C.
91.1
84.6
80.2
Δn (20°)
0.1086
0.1103
0.1027
Δε (20° C.)
10.8
10.2
10.5
K3/K1 (20°)
1.37
1.39
1.40
K3/pN (20° C.)
15.3
14.9
15.1
K1/pN (20° C.)
11.2
10.7
10.8
Vth/V (25° C.)
4.8
5.2
4.6
τr + d/msec (25° C.)
1.37
1.29
1.18
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 71 to 73 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which conventional liquid crystals having positive dielectric anisotropy were interposed.
Comparative Example 6
A liquid crystal panel of Comparative Example 6 was produced in the same manner as in Example 71 by interposing the liquid crystals having positive dielectric anisotropy indicated in Table 25, and the property values were measured. The results are presented in Table 25.
TABLE 25
Comparative
Example 6
5-Cy-Ph-F
5
7-Cy-Ph-F
6
2-Cy-Cy-Ph-OCFFF
11
3-Cy-Cy-Ph1-OCFFF
12
3-Cy-Cy-Ph-OCFFF
12
4-Cy-Cy-Ph-OCFFF
10
5-Cy-Cy-Ph3-F
9
5-Cy-Cy-Ph-OCFFF
12
3-Ph-VO-Ph1-CN
11
3-Cy-Cy-Ph3-CN
8
3-Cy-Oc-Ph3-F
4
Sum of composition ratios
100
Tni/° C.
92.1
Δn (20°)
0.094
Δε (20° C.)
11.7
Vsat/V (25° C.)
5.6
τr + d/msec (25° C., 6 V)
3.7
The liquid crystal panel of Comparative Example 6 in which liquid crystals having positive dielectric anisotropy were interposed, exhibited a slow response speed, a slightly smaller amount of light transmission, and particularly poor retention ratio and long-term reliability as compared with the liquid crystal panels of the invention.
Examples 74 and 75
The liquid crystals having positive dielectric anisotropy indicated in Table 26 were interposed between a first substrate and a second substrate in the same manner as in Example 71 and Comparative Example 6, and thus liquid crystal panels were produced.
TABLE 26
Example
Example
74
75
5-Cy-Ph-F
6
7-Cy-Ph-F
7
2-Cy-Cy-Ph1-F
5
2-Cy-Cy-Ph-OCFFF
12
9
3-Cy-Cy-Ph1-F
15
12
3-Cy-Cy-Ph3-F
10
3-Cy-Cy-Ph-OCFFF
16
12
4-Cy-Cy-Ph1-F
3
4-Cy-Cy-Ph-OCFFF
11
5-Cy-Cy-Ph3-OCFFF
12
12
5-Cy-Ph-Ph1-F
10
5-Cy-Ph-Ph1-OCFFF
10
3-Ph-Ph1-Ph3-F
11
1-Ph-T-Ph-6
6
5-Ph-T-Ph-O1
5
3-Cy-Ph1-T-Ph-2
7
2Cy-Cy-Ph-Ph-1
5
4-Cy-Cy-Ph-Ph-1
4
Sum of composition ratios
100
100
Tni/° C.
70.3
92.9
Δn (20° C.)
0.1154
0.1203
Δε (20° C.)
11.4
12.4
K3/K1 (20° C.)
1.41
1.48
K3/pN (20° C.)
15.2
15.7
K1/pN (20° C.)
10.8
10.6
Vth/V (25° C.)
4.6
4.2
τr + d/msec (25° C.)
0.92
1.04
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 74 and 75 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which conventional liquid crystals having positive dielectric anisotropy were interposed.
Example 76
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the other sides of the respective surfaces that faced each other, and an alignment film of horizontal orientation was formed on each of the reverse sides. The liquid crystals having positive dielectric anisotropy disclosed in Examples 71 to 75 and Comparative Example 6 were respectively interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300, AL-1051).
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 71 to 75 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Example 6 were interposed.
Example 77
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the respective surfaces that faced each other. Compositions obtained by adding 0.3% by mass of 2-methyl-acrylic acid 4′-{2-[4-(2-acryloyloxyethyl)phenoxycarbonyl]ethyl}biphenyl-4-yl ester to the liquid crystals having positive dielectric anisotropy as indicated in Examples 71 to 75 and Comparative Example 6 were interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300). While a driving voltage was applied between the electrodes, the liquid crystal panels were irradiated with ultraviolet radiation for 600 seconds (3.0 J/cm 2 ), and thus a polymerization treatment was carried out.
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 71 to 75 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Example 6 were interposed.
Example 78
An electrode structure such as illustrated in FIG. 4 was produced on a second substrate, and a first substrate having no electrode structure provided thereon was used. An alignment film of vertical orientation was formed on each of the other sides of the respective surfaces that faced each other, and an alignment film of horizontal orientation was formed on each of the reverse sides. Each of the compositions obtained by adding 0.3% by mass of 2-methyl-acrylic acid 4′-{2-[4-(2-acryloyloxyethyl)phenoxycarbonyl]ethyl}biphenyl-4-yl ester to the liquid crystals having positive dielectric anisotropy as indicated in Examples 71 to 75 and Comparative Example 6 was interposed between the first substrate and the second substrate, and thus liquid crystal panels were produced (d ITO =4 μm, d gap =4 μm, alignment film: SE-5300, AL-1051). While a driving voltage was applied between the electrodes, the liquid crystal panels were irradiated with ultraviolet radiation for 600 seconds (3.0 J/cm 2 ), and thus a polymerization treatment was carried out.
The liquid crystal panels in which the liquid crystals having positive dielectric anisotropy disclosed in Examples 71 to 75 were interposed, realized faster response speeds, larger amounts of light transmission, a reduction in light leakage caused by external pressure, wider viewing angles, and higher contrast ratios, as compared with liquid crystal panels in which liquid crystals having positive dielectric anisotropy disclosed in Comparative Example 6 were interposed. | Provided is a liquid crystal display device of the VAIPS mode which uses a liquid crystal material having positive dielectric anisotropy and which has a fast response speed and excellent viewing angle characteristics without having a special cell structure such as pixel partitioning. Disclosed is a liquid crystal display device including: a plurality of independently controllable pixels; and a liquid crystal composition layer having positive dielectric anisotropy, wherein electrodes for controlling the pixels are provided on at least one of first and second substrates that interpose the liquid crystal phase, the long axis of the liquid crystal molecules of the liquid crystal composition layer is aligned substantially perpendicularly to the substrate surface or is in a hybrid alignment, the liquid crystal composition contains one kind or two or more kinds of compounds selected from a specific liquid crystal compound group, and the transmittance of the light that penetrates through the liquid crystal composition layer is modulated at the electric field generated by the electrode structure. | 2 |
COPYRIGHT NOTICE
A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.
FIELD OF THE INVENTION
This invention relates generally to the field of hardware description languages. More particularly, this invention relates to a method of providing regular expression support for module iteration (instantiation) and interconnection in hardware description languages.
BACKGROUND OF THE INVENTION
A hardware description language (HDL) is a computer language used to describe electronic circuits. The description can describe the circuit at a number of different levels. For example, a hardware description language can be used to describe the interconnection of modules, sub-modules, transistors, resisters, capacitors, etc. Hardware description languages can also be utilized to describe the logical operation of logic gates, flip-flops and the like in digital systems and to describe the transfer of vectors of information between registers.
One of the most popular hardware description languages is the IEEE standard Verilog™. In this, and other HDLs, when multiple iterations of the same type of component (module) are used in a particular arrangement and interconnected with one another and/or other types of modules, an individual description of each module “instance” of each module type is generated to represent the particular module instance and it's interconnection. Manually generating each iteration of a particular module type can be quite tedious. So, the IEEE, in its current working draft of IEEE 1364 (draft 5) Verilog™ proposal (See IEEE Proposed Standard 1364-2000 (Draft 5) “IEEE Standard Hardware Description Language Based on the Verilog Hardware Description Language”, IEEE, Inc., New York, N.Y., USA, March, 2000, and “IEEE Standard 1076-1993 IEEE VHDL Language Reference Manual”, IEEE, Inc., New York, N.Y., USA, Jun. 6, 1994) proposes a standard technique using preprocessing at the interconnect level in a “for loop” to achieve iteration and interconnection. The example provided in this proposal is repeated below as EXAMPLE 1 for convenience:
genvar i;
generate
for (i=0; i<4; i=i+1)
begin:word
sms_16b216t0 p
(.clk
(clk),
.csb
(csx),
.ba
(ba[0]),
.addr
(adr[10:0]),
.rasb
(rasx),
.casb
(casx),
.web
(wex),
.Udqm
(dqm[2*i+1]),
.ldqm
(dqm[2*i]),
.dqi
(data[15+16*i;16*1]),
.dev_id
(dev_id3[4:0])
);
EXAMPLE 1
In this example, a module named sms — 16b216t0 is to be instantiated and interconnected four times as the variable “i” is iterated from values 0 through 4. Each of the lines following the first line represents a port on the module with signal names, as will be appreciated by those familiar with Verilog™.
Unfortunately, “for loops” and “generate loops” suffer from several disadvantages. The use of “for loops” in preprocessing was added as an extension to the Verilog language in response to the user community's desire to provide a capability similar to that of the VHDL “generate loop”. However, “for loops” and “generate loops” can be burdensome and inefficient to code. In addition, when “for loops” and “generate loops” are used in preprocessing to generate the instances and connections, but the connection specification still has to be checked against the modules being connected to assure that the preprocessing was specified successfully. This is because the interconnect module signals are not developed from the modules being interconnected. Instead, the interconnection module signal specification is checked against the modules being interconnected. This leads to potential errors that can reduce the efficiency of the coding of the interconnection.
It is generally recognized as good hardware design practice to use the same signal name in a receiving module as in a transmitting module (see for example, M. Keating and P. Bricaud, “Reuse Methodology Manual”, Kluwar Academic Publishers, 1999. ). For example, if the clock signal name in the design for a clock-generating module is “CK”, use of “CK” as the signal name for the corresponding nets on modules that receive that clock signal makes the net function clear to anyone reading the design description. This accepted practice has prompted many designers to develop a program that automatically generates a module that interconnects sub-modules. Designers in many development labs have turned to preprocessors, outside of the standard HDLs (Verilog or VHDL) language definition, to automatically generate interconnect HDL modules. These preprocessors are generally written in the PERL language, and may invoke PERL's support of regular expression matching. They often combine input-output port naming of the interconnected sub-modules with rules supplied from another file.
BRIEF SUMMARY OF THE INVENTION
The present invention relates generally to a regular expression support for hardware description languages and methods therefor. Objects, advantages and features of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of the invention.
In accordance with an exemplary embodiment, a method consistent with the invention of iterating instances and connections in a Hardware Description Language include: receiving hardware description language (HDL) code with embedded regular expressions to define instances and interconnections of a module; identifying the regular expressions within the code; and elaborating the instances and interconnections of the module based upon the regular expressions.
Another method of iterating instances and interconnections in a hardware description language consistent with an embodiment of the invention includes: providing Hardware Description Language (HDL) code using regular expressions to define instances and interconnections of a module; and instantiation and interconnection processing the HDL code by: analyzing the code to identify the regular expressions; applying HDL grammar rules to the code; generating a data structure corresponding to the module defined by the code; elaborating the data structure into instances and interconnections of the module defined by the regular expressions in the code; and generating HDL compliant text by traversing the instances and interconnections of the elaborated data structure and translating each instance and interconnection into HDL compliant text.
A computer system for processing Hardware Description Language (HDL) code consistent with embodiments of the invention includes a processor. An input circuit coupled to the processor receives HDL code having embedded regular expression descriptions of instances and interconnections. A storage arrangement is coupled to the processor for storing computer programs and data. A program receives the HDL code and elaborates the HDL code into explicit instances and interconnections describing a selected element of hardware.
In another embodiment consistent with the invention, an electronic storage medium stores instructions which, when executed on a programmed processor, carry out a process of iterating instances and interconnections in a Hardware Description Language (HDL) including: receiving Hardware Description Language code with embedded regular expressions to define instances and interconnections of a module; identifying the regular expressions within the code; and elaborating the instances and interconnections of the module based upon the regular expressions.
A method of describing a module in a Hardware Description Language (HDL) includes: providing a module name using HDL code; creating port descriptions for a port on the module using the HDL code; describing instantiation and interconnection of the module using regular expressions within the HDL code; and elaborating the module according to the regular expressions describing the instantiation and interconnection.
Many variations, equivalents and permutations of these illustrative exemplary embodiments of the invention will occur to those skilled in the art upon consideration of the description that follows. The particular examples above should not be considered to define the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the invention believed to be novel are set forth with particularity in the appended claims. The invention itself however, both as to organization and method of operation, together with objects and advantages thereof, may be best understood by reference to the following detailed description of the invention, which describes certain exemplary embodiments of the invention, taken in conjunction with the accompanying drawings in which:
FIG. 1 is a flow chart illustrating a process consistent with the present invention.
FIG. 2 is a block diagram of a computer system operating in accordance with an embodiment of the present invention.
FIG. 3 is a diagram of a D flip-flop described by EXAMPLE 2.
FIG. 4 is a diagram showing the interconnection of four instances of a D flip-flop in accordance with the hardware description of EXAMPLE 6, as instantiated and interconnected by the descriptions of EXAMPLES 3-5.
DETAILED DESCRIPTION OF THE INVENTION
While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail specific embodiments, with the understanding that the present disclosure is to be considered as an example of the principles of the invention and not intended to limit the invention to the specific embodiments shown and described.
The term “regular expressions” as used herein are expressions consistent with the meaning of the term as used in the “Perl” programming language to describe expressions that are used to match text using special characters. The Perl programming language contains support for a rich set of features associated with regular expressions. Regular expressions are described in most tutorials on the Perl programming language. Regular expressions are sometimes referred to in the literature as “regexes”, “RE's” and “regexps”.
An embodiment of the present invention, as prototyped, supports module iteration and interconnection within the hardware description language. Compared with the current HDL for-loop and generate-loop techniques, the prototype implementation has the advantages of: improved designer productivity by use of interconnected submodule port names that the designer has already entered and rule-based generated interconnection that supports consistency across a project.
The present invention utilizes regular expressions embedded within an HDL to accomplish the module iteration (instantiation) and interconnection. The regular expressions used to implement this invention are preferably a subset of standard Perl regular expressions used to call out the desired iteration and interconnection. Details of supported regular expressions supported by Perl are readily publicly available, for example, in “Programming Perl” Third Edition, by L. Wall, T. Christiansen, J. Orwant—O'Reilly & Associates, Sebastopol, Calif., July, 2000. Several of the connection rules used to implement a prototype of the present invention (utilizing the public domain regx.c program, Copyright 1993, version 0.12 available from the Free Software Foundation, Inc., 675 Mass Avenue, Cambridge, Mass. 02139 to handle regular expressions) is given in TABLE 1 below. Alternatives to regx.c can be readily developed by those skilled in the art by reference to the regular expressions and their associated rules given in TABLE 1 below.
TABLE 1
Regular
HDL
expression
Match rule
Applicability
[a-d0-4]
matches any character of set
port
instance
string1 | string2 |
matches string1 or string2 or string3
port
instance
string3
.
matches any [a-ZA-Z0-9_] character
port
x?
matches 0 or 1 x's, where x is any of
port
the above
x*
matches 0 or more x's
port
x+
matches 1 or more x's
port
$
matches the end-of-string
port
(regular
remembers the match for later
port
instance
expression)
reference
To create the initial code used by the present invention to iterate and interconnect various modules, Perl-like HDL code can be generated using the above rules. Search tools and text editors have used regular expressions for many years, thus, regular expression matching and search library functions suitable for use or modification to implement the present invention are widely available, for example from the Free Software Foundation, Inc.
Once the initial code containing regular expressions is generated applying the appropriate regular expression syntax to effect the iteration and connection, the code can be pre-processed, in one embodiment of the invention, to generate the final Verilog™ code as illustrated in the flow chart 100 of FIG. 1 . In this flow chart, the process starts with manual generation of code using regular expressions to designate instances and connections at 105 . At 110 , the code is analyzed, e.g. in a Verilog parser, to recognize key words, operators, user names and regular expressions in a lexical analyzer process. Lexical analyzer (parser) software is known and available from various sources including the “flex” program (fast lexical analyzer generator) Copyright 1990, Regents of the University of California and the “Bison” program (YACC compatible parser generator, i.e. syntax analyzer) programs available from the Free Software Foundation, Inc. These tools can be adapted to provide the Verilog™ lexical and syntax analysis used to implement the present invention. This and other lexical analyzer programs can be extended to recognize regular expressions.
When key words, operators, user names or regular expressions are recognized in 110 , calls are made to a Verilog™ syntax analyzer at 120 that puts the code in a correct grammatical context consistent with Verilog™ syntax rules, if necessary, or provide messages or fixes where grammar errors are encountered. Syntax analyzer 120 makes calls to a data structure generator at 130 that represents the code in the form of data structures based on the Verilog™ language with extensions to account for the regular expressions. The data structure generator generates any suitable data structure (e.g. list, linked list, double linked list, etc.) for representing the module in accordance with the regular expression. Verilog™ syntax analyzer software is known and available from various sources as described above.
The data structures created at 130 are processed by an HDL elaboration engine at 140 to elaborate instances of the data structures based upon traversing the data structures and expanding the regular expressions into instances and interconnections. At this stage, explicit connections are inserted into the data structures wherever implicit connections existed in the initial code. In a prototype, this was accomplished by invoking the public domain regex.c program described above.
Finally, the data structures resulting from 140 are processed by a text generator at 150 that traverses the detailed data structures produced by 140 to create standard Verilog™. This can be readily accomplished by those having ordinary skill in the art by traversing the data elements of each of the detailed data structures and generating Verilog™ code that describes the design represented by these detailed data structures. The Verilog™ code is then output at 155 . Thus, blocks 110 , 120 , 130 , 140 and 150 together serve to elaborate the HDL code of 105 (that uses regular expressions to represent a hardware description) into code that provides an explicit detailed description of the hardware. Thus, these steps can collectively be described as elaborating the HDL code of 105 .
While the above process is described in terms of flow chart 100 depicting a linear flow from top to bottom, the process may be implemented in a somewhat recursive hierarchical manner. That is, upon recognition of a regular expression at 110 , calls can be made to the grammar rule checker 120 which in turn may call the data structure generator 130 . Intermediate results can then be stored and the process returned to 110 to identify the next significant program code element. Moreover, although disclosed in terms of a pre-processing method, since the regular expressions are used as an extension of the standard HDL, the process could be implemented within the HDL, e.g. made a part of Veriog™. Other equivalent variations of the process will occur to those skilled in the art.
Referring now to FIG. 2, an overall system diagram using the present invention is illustrated as 200 . HDL code 204 using regular expressions embedded therein to define interconnections and instances is generated to describe the hardware of interest using any suitable mechanism. This code 204 is supplied to an input interface 210 (e.g. via keyboard entry, disc or electronic transfer) of a computer system 220 . This interface is coupled in a conventional manner via a system bus 228 to a processor (e.g. a microprocessor) 234 . Also connected to processor 234 via system bus 228 is memory and mass storage 240 , which may encompass semiconductor Random Access Memory (RAM), Read Only Memory (ROM) as well as mass storage devices such as hard disc drive(s) and other suitable storage devices as is known in the art. The memory and/or mass storage runs a Hardware Description Language (HDL) 244 which includes or operates in conjunction with a program or programs 250 that provides the functions described in connection with FIG. 1 above for elaboration of HDL code with embedded regular expression descriptions of instances and interconnections into explicit instances and interconnections. Once the code 204 has been processed by 250 , normal functions can be carried out using the HDL 244 in a known manner.
In order to understand how regular expressions can be used to accomplish instantiation and interconnection, a simple example in Verilog™ is useful. Consider a circuit that includes four D flip flops. In order to represent this circuit in Verilog™, four instances of a D flip flop such as D flip-flop 300 of FIG. 3 are required. D flip-flop 300 has a D input 314 , a Q output 316 and a clock input 350 , and operates as a conventional well known positive edge triggered D flip-flop would be expected to operate.
An example of Verilog™ code for a D flip flop module such as D flip-flop 300 is shown as EXAMPLE 2 below:
module dff(clk,d,q);
input clk;
input d;
output q;
reg q;
always @ (posedge clk)
q <= d;
endmodule
EXAMPLE 2
In EXAMPLE 2, the module is called “dff” with D and clock inputs “d” and “clk”, respectively, and a Q output “q” that responds to the positive edge of the signal “clk” to set the value of “q” to equal the value of “d”.
The following three examples (EXAMPLES 3-5) show the use of regular expressions to generate Verilog™ instances and interconnections of the D flip-flop of FIG. 3 . In EXAMPLE 3, the bit selection is derived from the regular expression implying four instances:
module dffX4(clk,d,q);
input clk;
input [0:3] d;
output [0:3] q;
dff f([0-3]) (
.d
(d[$1]),
.q
(q[$1])
);
endmodule
EXAMPLE 3
In EXAMPLE 3 above, the instances of “dff” are represented by the term “dff×4” to represent that four instances are required. The common clock signal “clk” is a common interconnection among all four flip flops. The fact that four Instances (zero through three) of the “d” input and “q” output are to be created is represented by the bracketed terms “[ 0 : 3 ]”. The input and output ports on the instantiated D flip flops are designated by the period preceding the port names as “.d” and “.q” with the respective signals (representing interconnections) at these ports designated as “d[$ 1 ]” and “q[$ 1 ]”.
In the next EXAMPLE 4, the connection rules for “d” and “q” are combined:
module dffX4(clk,d,q);
input clk;
input
[0:3] d;
output
[0:3] q;
dff f([0-3]) (
.(q|d)
($2 [$1])
);
endmodule
EXAMPLE 4
In EXAMPLE 4, the connection for “q” and “d” are joined in a single statement with their signals represented as the scalars “$ 2 ” and “$ 1 ” respectively as will be appreciated by those skilled in Perl or other languages using regular expressions.
Finally, in EXAMPLE 5 below, shareable interconnection rules are defined:
‘define RULE_D .d (d[$1])
‘define RULE_Q .q (q[$1])
module dffX4(clk,d,q);
input clk;
input
[0:3] d;
output
[0:3] q;
dff f([0-3]) (
‘RULE_D ,
‘RULE_Q
);
endmodule
(‘define for specifying text macros is a standard part of the
Verilog language) .
EXAMPLE 5
In EXAMPLE 5, the use of shared interconnection rules is illustrated, wherein interconnection rules are defined using a “define RULE” statement to simplify data entry and provide ease of consistency in iterating common connections.
In accordance with the present invention, Verilog™ code is generated from the above three examples as shown below as EXAMPLE 6 by carrying out a process on the code consistent with the present invention to produce:
module dffX4 (clk,d,q);
input
clk;
input [0:3] d;
output [0:3] q;
dff f0 (
.d
( d[0] ),
.q
( q[0] ),
.clk
( clk ));
dff f1 (
.d
( d[1] ),
.q
( q[1] ),
.clk
( clk ));
dff f2 (
.d
( d[2] ),
.q
( q[2] ),
.clk
( clk ));
dff f3 (
.d
( d[3] ),
.q
( q[3] ),
.clk
( clk ));
endmodule // dffX4
EXAMPLE 6
The hardware description of EXAMPLE 6 is illustrated schematically as 400 in FIG. 4 . Each of four instances of the D flip-flop f 1 , f 2 , f 3 and f 4 are shown respectively as 410 , 420 , 430 and 440 . Each of the clock ports are connected by designation of the common clock signal “clk” shown as 450 in each instance. Input signals “d[ 0 ]”, “d[ 1 ]”, “d[ 2 ]” and “d[ 3 ]” are shown as 414 , 424 , 434 , and 444 respectively. Similarly, output signals “q[ 0 ]”, “q[ 1 ]”, “q[ 2 ]” and “q[ 3 ]” are shown as 416 , 426 , 436 , and 446 respectively.
In contrast with the code of EXAMPLE 6, the following EXAMPLE 7 uses the Verilog™ 2000 Draft 5 proposed standard preprocessor using a “for-loop”, to derive corresponding instances and interconnections:
module dffx4 (clk,d,q);
input
clk;
input [0:3] d;
output [0:3] q;
dff f0 (
genvar i
generate
for (i=0; i<4; i=i+1)
begin : inst
dff d (
.clk (clk),
.p (p[i]),
.q (q[i])
);
end
endmodule
EXAMPLE 7
The instance names from the IEEE standard of EXAMPLE 7 would be “inst[ 0 ].p”, “inst[ 1 ].p”, “inst[ 2 ].p”, “inst[ 3 ].p”, (“inst” is a user-specified name, not a Verilog™ language reserved word).
Now consider how the circuit of EXAMPLE 1 given above can be iterated and interconnected using an embodiment of the present invention. The code used for this is given as EXAMPLE 8 below:
sms_16b216t0 p([0-3]) (
.dqi(data[15+16*$1:16*$1]),
.(cs|ras|cas|we)b ($2x),
.ba(ba[0]),
.addr(adr[10:0]),
.udqm(dqm[2*$1+1]),
.ldqm(dqm[2*$1]),
.dev_id(dev_id3[4:0]) );
EXAMPLE 8
It should be noted that alternative forms of regular expressions can be provided for such as, for example:
sms_16b216t0 p([0123])
sms_16b216t0 p(0|1|2|3)
sms_16b216t0 p([0-3])
are acceptable and have the same effect.
The following code shown as EXAMPLE 9 is the resultant Verilog™ code obtained from processing in accordance with EXAMPLE 8 of the present invention:
sms_16b216t0 p0 (
.dqi(data[15:0]),
.clk(clk),
.csb(csx),
.cke(cke),
.ba(ba[0]),
.addr(adr[10:0]),
.rasb(rasx),
.casb(casx),
.web(wex),
.udqm(dqm[1]),
.ldqm(dqm[0]),
.dev_id(dev_id3[4:0]) );
sms_16b216t0 p1 (
.dqi(data[31:16]),
.clk(clk),
.csb(csx),
.cke(cke),
.ba(ba[0]),
.addr(adr[10:0]),
.rasb(rasx),
.casb(casx),
.web(wex),
.udqm(dqm[3]),
.ldqm(dqm[2]),
.dev_id(dev_id3[4:0]) );
sms_16b216t0 p2 (
.dqi(data[47:32]),
.clk(clk),
.csb(csx),
.cke(cke),
.ba(ba[0]),
.addr(adr[10:0]),
.rasb(rasx),
.casb(casx),
.web(wex),
.udqm(dqm[5]),
.ldqm(dqm[4]),
.dev_id(dev_id3[4:0]) );
sms_16b216t0 p3 (
.dqi(data[63:48])
.clk(clk),
.csb(csx),
.cke(cke),
.ba(ba[0]),
.addr(adr[10:0]),
.rasb(rasx),
.casb(casx),
.web(wex),
.udqm(dqm[7]),
.ldqm(dqm[6]),
.dev_id(dev_id3[4:0]) );
EXAMPLE 9
EXAMPLE 10 and EXAMPLE 11A and EXAMPLE 11B below provides another example of the use of the present invention to instantiate and interconnect using regular expressions and further illustrates the generation of explicit code from implicit interconnections such as “core_clk” and “log_reset_L”. This example also illustrates further use of scalars and several variations in how designers can use variations in regular expressions to represent instances and interconnections. This example was generated using an example circuit passed through the prototype system described above to produce two instances of the module.
koaqd_oaq_data4
oaqd([01])
(
.mdprd0_corr_err
( mdprd0_$1_corr_err ),
.(mbt|mdprd|msc) ([01])_(.*)$
( $2$3_$1_$4 ),
.mhg_oaqd_(.*)$
( mhg_oaqd$1_$2 ),
.mhg_corr_err_index
( 6’b0 ),
.qdctl(.*)$
( qdctl$1$2 ),
.mopc_s2c_(.*)$
( mopc$1_s2c_$2 ),
.mqb_qmu_data
( qmu_data ),
.oaqdp_(.*)$
( oaqdp$1_$2 )
);
EXAMPLE 10
In EXAMPLE 10, except for the regular expression text added in, this is standard Verilog where:
“koaqd_oaq_data 4 ” is the submodule type name
“oaqd([ 01 ])” is the instance name
“mdprd 0 _corr_err” is a port name on “koaqd_oaq_data 4 ”
“mdprd 0 _$ 1 _corr_err” is a signal name connected to “mdprd 0 _corr_err”.
This example illustrates several points regarding the current invention's support for iteration and interconnection:
the regular expressions within parenthesis in instance and port names,
the “$” denoting the end of the port name, and
the “$n” in the signal name.
The “([ 01 ])” added in the instance name indicates that the designer wants two instances of “koaqd_oaq_data 4 ” namely “oaqd 0 ” and “oaqd 1 ”. Enclosing the range of values within parenthesis means that the range element ( 0 or 1 , depending on the instance) can be referenced from scalar “$ 1 ” to form part of a signal name, as shown in the signal “mdprd 0 _$ 1 _corr_err”. The port regular expression “. (mbt|mdprd|msc) ([ 01 ])_(.*)$” provides the rule that matches any port on submodule type “koaqd_oaq_data 4 ” that matches the 8 combinations of the first two regular expressions and suffixed with any character.
The code of EXAMPLE 10, after passing through the preprocessing of the present invention, produces the two regular expression generated instances of the module “koaqd_oaq_data 4 ” shown in EXAMPLE 11A and 11B below:
koaqd_oaq_data4 oaqd0 (
.mdprd0_corr_err
( mdprd0_0_corr_err ),
.mbt0_found_ff
( mbt0_0_found_ff ),
.mbt1_found_ff
( mbt1_0_found_ff ),
.mdprd0_data2oaqd
( mdprd0_0_data2oaqd ),
.mdprd0_wr_index
( mdprd0_0_wr_index ),
.mdprd0_wr_start
( mdprd0_0_wr_start ),
.mdprd1_corr_err
( mdprd1_0_corr_err ),
.mdprd1_data2oaqd
( mdprd1_0_data2oaqd ),
.mdprd1_wr_index
( mdprd1_0_wr_index ),
.mdprd1_wr_start
( mdprd1_0_wr_start ),
.msc0_wr_index
( msc0_0_wr_index ),
.msc0_wr_trans
( msc0_0_wr_trans ),
.msc1_wr_index
( msc1_0_wr_index ),
.msc1_wr_trans
( msc1_0_wr_trans ),
.mhg_oaqd_addr_lower
( mhg_oaqd0_addr_lower ),
.mhg_oaqd_index
( mhg_oaqd0_index ),
.mhg_oaqd_index_valid
( mhg_oaqd0_index_valid ),
.mhg_oaqd_length
( mhg_oaqd0_length ),
.mhg_corr_err_index
( 6'h00 ),
.qdct1_corr_err
( qdctl0_corr_err ),
.mopc_s2c_oaqd_addr_lower
(mopc0_s2c_oaqd_addr_lower
),
.mopc_s2c_oaqd_index
( mopc0_s2c_oaqd_index ),
.mopc_s2c_oaqd_type
( mopc0_s2c_oaqd_ptype ),
.mopc_s2c_trans_valid
( mopc0_s2c_trans_valid ),
.mqb_qmu_data
( qmu_data ),
.oaqdp_cdp_data
( oaqdp0_cdp_data ),
.oaqdp_data2mdp
( oaqdp0_data2mdp ),
.core_clk
( core_clk ),
.log_reset_L
( log_reset_L ),
.mpd_intraPD
( mpd_intraPD ),
.mpd_read_only_region
( mpd_read_only_region ),
.mpd_txn_valid
( mpd_txn_valid ),
.sync_reset_L
( sync_reset_L ));
EXAMPLE 11A
koaqd_oaq_data4 oaqd1 (
.mdprd0_corr_err
( mdprd0_1_corr_err ),
.mbt0_found_ff
( mbt0_1_found_ff ),
.mbt1_found_ff
( mbt1_1_found_ff ),
.mdprd0_data2oaqd
( mdprd0_1_data2oaqd ),
.mdprd0_wr_index
( mdprd0_1_wr_index ),
.mdprd0_wr_start
( mdprd0_1_wr_start ),
.mdprd1_corr_err
( mdprd1_1_corr_err ),
.mdprd1_data2oaqd
( mdprd1_1_data2oaqd ),
.mdprd1_wr_index
( mdprd1_1_wr_index ),
.mdprd1_wr_start
( mdprd1_1_wr_start ),
.msc0_wr_index
( msc0_1_wr_index ),
.msc0_wr_trans
( msc0_1_wr_trans ),
.msc1_wr_index
( msc1_1_wr_index ),
.msc1_wr_trans
( msc1_1_wr_trans ),
.mhg_oaqd_addr_lower
( mhg_oaqd1_addr_lower ),
.mhg_oaqd_index
( mhg_oaqd1_index ),
.mhg_oaqd_index_valid
( mhg_oaqd1_index_valid
),
.mhg_oaqd_length
( mhg_oaqd1_length ),
.mhg_corr_err_index
( 6'h00 ),
.qdct1_corr_err
( qdctl1_corr_err ),
.mopc_s2c_oaqd_addr_lower
(
mopc1_s2c_oaqd_addr_lower ),
.mopc_s2c_oaqd_index
( mopc1_s2c_oaqd_index ),
.mopc_s2c_oaqd_type
( mopc1_s2c_oaqd_type ),
.mopc_s2c_trans_valid
( mopc1_s2c_trans_valid
),
.mqb_qmu_data
( qmu_data ),
.oaqdp_cdp_data
( oaqdp1_cdp_data ),
.oaqdp_data2mdp
( oaqdp1_data2mdp ),
.core_clk ( core_clk ),
.log_reset_L
( log_reset_L ),
.mpd_intraPD
( mpd_intraPD ),
.mpd_read_only_region
( mpd_read_only_region ),
.mpd_txn_valid
( mpd_txn_valid ),
.sync_reset_L
( sync_reset_L ));
EXAMPLE 11B
The present invention is preferably implemented using one or more programmed processors executing programming instructions that are broadly described above in flow chart form. However, those skilled in the art will appreciate that the processes described above can be implemented in any number of variations and in many suitable programming languages without departing from the present invention. For example, the order or sequencing of certain operations carried out can often be varied, and additional operations can be added without departing from the invention. Error trapping can be added and/or enhanced and variations can be made in user interface and information presentation without departing from the present invention. Moreover, although the invention described with reference to the Verilog™ hardware description language, the invention may be applicable to other HDLs to accomplish iteration and/or connection. Also, as previously mentioned, the process described above can readily be integrated within the HDL since it operates as an extension to the HDL syntax, rather than being carried out as a separate pre-processing operation. In either instance, the process can be described by a set of instructions implementing the processes described and stored on a computer storage medium such as a magnetic disc, optical disc, magneto-optical disc, semiconductor memory, etc. Many such variations and modifications are contemplated and considered equivalent.
While the invention has been described in conjunction with specific embodiments, it is evident that many alternatives, modifications, permutations and variations will become apparent to those of ordinary skill in the art in light of the foregoing description. Accordingly, it is intended that the present invention embrace all such alternatives, modifications and variations as fall within the scope of the appended claims. | A method of providing hardware description language-embedded regular expression support for module iteration and interconnection. Regular expressions such as those used in the Perl programming language are used in a preprocessing process to generate instances and interconnections in a hardware description to automate the generation of repetitive code for a Hardware Description Language (HDL). This is accomplished by generating HDL code with embedded regular expressions, analyzing the code to identify the regular expressions and checking to see that the code complies with the HDL grammar rules. A data structure is generated for each module or submodule and these data structures are then elaborated to expand them into the instances and interconnections. A text generator traverses the elaborated data structures and generates HDL compliant text. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
The present application is a continuation of my prior application Ser. No. 450,712, filed Apr. 29, 1974, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to an automatic high garage with a plurality of parking levels and parking spaces arranged in a circle. In this high garage the cars are parked and retrieved by automatic parking machines.
Nowadays, in most cases the parking of cars is effected by the respective driver himself who chooses a free lot, i.e., space, on a parking level within concrete constructions. These concrete constructions are very expensive to construct and they need an unfavourable large total floor space in relation to the real effective parking area efficiency. The finding of free lots within the respective parking level is time-consuming and causes an increased exhaust gas output resulting from driving in low gear. The construction of automated car parking garages has been tried without success, resulting in even higher building expenses, still fewer numbers of parking spaces or in an insufficient car turnover in relation to concrete constructions where cars are parked manually.
SUMMARY OF THE INVENTION
The object of this invention is to develop a high garage of the above mentioned nature, which can be designed economically with optical space efficiency using standard components of mechanical engineering, steel, or reinforced precast concrete industries, controlled fully-automatic or semi-automatic and guaranteeing a great exchange of parked cars.
This and other aims and features of the present invention will become more apparent upon a consideration of the following description in connection with the accompanying drawings, wherein:
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is the front elevation of an automatic high garage in accordance with the present invention;
FIG. 2 is a plan view of the high garage at the level of the entrance and exit lots of the cars;
FIG. 3 is a segment sector of a high garage in plan view with parking machine shown;
FIG. 4 is a section on line IV--IV across the segment sector of FIG. 3;
FIG. 5 is a section on line V--V across the segment sector of FIG. 3;
FIGS. 6A, 6B and 6C show the function principle of a retrieval unit in accordance with the present invention;
FIG. 7 is a section on line VII--VII across the segment sector of FIG. 3;
FIG. 8 shows an entrance or exit lot, respectively; and
FIG. 9 is the plan view of an entrance or exit lot, respectively, according to FIG. 8.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The circular high parking garage of FIGS. 1-9 comprises, within its periphery, several parking levels 1. The circle confined by the parking levels 1 represents the operating zone 2. There are twenty parking levels 1 one above the other. Each parking level 1 accommodates 25 cars. The cars are conveyed by manually driving them to the entrance and exit zone 3. Afterwards, they are fed by the parking machines 5 to the free parking lots 4' of one of the parking levels 1. The parking machines 5 operate automatically inside the oerating zone 2. The control-commands to the parking machines 5 for parking and retrieval operations are transmitted from a control center 6 which is placed at the front of the complete building. The control is effected by keyboard, punched cards or a computer. The multilevel parking lots 4' transfer their load reactions to the foundation through vertical supports 7. Always three supports 7 constitute a triangular frame with cross beams 8 and longitudinal beams 9 carrying tracks 10 resistant to deflection and forming the driveways for the cars. The ring beams 8' with mounting beams 8" constitute a closed circle around the parking levels 1. Wall strip panels 12 are mounted on the ring beams 8' and mounting beams 8" by means of lateral braces 11. The tracks 10 are inclined towards the wall strip panels 12 and in their rear points are mounted drive limit stops 13. The lateral outer edges of the tracks 10 have an edge 10' to discharge drip-water from the parked cars (FIG. 7). This ensures a water flow off in direction to the wall strip panels 12. The parking machines 5 run on a circular floor rail 14 and can reach every parking lot 4,4' within the entire high garage. The parking machines 5 are guided by one center column 15 and they transfer their effective horizontal forces to the center column 15 through booms 17, 17'. The center column 15 constitutes also the central supporting element for the roof construction 16. The booms 17, 17' are mounted on slewing rings 18 on the central column 15. The booms 17, at the level of the parking machine floor-beams serve also as cable bridges for the main current from slip-ring elements 19 and for control-impulse cables. Each parking machine 5 is equipped with a load table unit 20. It comprises a base frame 22 which carries two load girders 23 with mounted tracks 10 resistent to deflection as driveways for the cars, similarly to the parking lots 4, 4'. The retrieval unit 21 moves horizontally for the parking and retrieval operations of cars. It is driven by a chain drive 21' and runs with four plastic rollers 24, 24' on the tracks 10. Preceding the extending action of the retrieval unit 21, swing in intermediate rollers 25 by means of a driving motor 26. The intermediate rollers 25 bridge the safety gap between the tracks 10 of the parking lots 4, 4' and the tracks 10 of the parking machines 5. The retrieval unit 21 moves under the cars by means of the driving motor 27 and the chain drive 21'. There are always joined in a bearing block 28 one guide roller 27' and one driving roller 27". The bearing blocks 28 are adjusted by two threaded rods 30 in longitudinal direction corresponding to the respective wheel position of the cars to be parked. For this purpose, the bearing blocks 28 slide in slotted links 29. Universal joints 30' connect the slotted links 29 with the main girder 31 of the retrieval unit 21. The slotted links 29 with bearing blocks 28 are width-adjusted by a threaded rod 30" corresponding to the respective track dimension of the cars to be parked. The front part of the main girder 31 carries moreover two brackets with mounted plastic rollers 24'. These plastic rollers 24' run on the tracks 10 of the parking spaces 4, 4'. The rear of the main girder 31 is guided within guide profiles 33 by means of four guide rollers 32. This part of the retrieval unit 21 is not covered by the cars to be parked, therefore it carries the two driving motors 34 of the threaded rods 30 and the driving motor 35 of the threaded bar 30". During the width-adjustment of the slotted links 29 with bearing blocks 28 and guide and driving rollers 27', 27" the driving motors 34 slide within the slotted link 35'. The slotted link 35' is rigidly connected with the main girder 31. If the retrieval unit 21 is extended, the plastic rollers 24' are on the tracks 10 of the parking lots 4, 4', whereas the plastic rollers 24 remain on the tracks 10 of the parking machines 5. The parking machines 5 are otherwise constructed as two-mast stacker cranes.
The preparation of the cars to be parked is effected within the parking lots 4 of the entrance and exit zone 3 by manual driving of the cars onto the parking lots 4, that means by the individual driver himself. The triangular spaces 36 between the tracks 10 are covered with grids to ensure that it is safe to place the cars in position and leave them, as well as for the reverse operation of driving out the cars. The parking lots 4 of the entrance and exit zone 3 differ moreover from the parking lots 4' because, at the former are installed two rollers 37 in the tracks 10 instead of rigidly mounted drive limit stops 13. When the rear wheels of the cars run over the rollers 37 an optical signal is actuated. In addition a drive limit bar 39 is mounted at the vertical supports 7. The drive limit bar 39 swivels by means of an electro-mechanical drive. The entrance openings of the parking lots 4 are closed by a two-piece sliding door 40. Parking and retrieval operations are executed as follows: The cars to be parked are driven to the parking lots 4 of the entrance and exit zone 3, running onto the tracks 10. After the rear wheels have run over the rollers 37 a contact between the rollers 37 and the rear wheels is ensured by the slope of the tracks 10, this guaranteeing a safe stop of the cars. The driver leaves the automatic high garage by stepping over grids of the triangular free spaces 36. The most favourably placed parking machine 5 relative to the preselected free parking lot 4' is chosen from the control center 6 by means of a "tell-tale" light panel indicating the movements of the parking machines 5, or a parking lot 4' and charging machine 5 is determined by a computer optimiser after a button is pressed. The selected parking machine 5 moves to the parking lot 4. The drive limit bar 39 is slewed through 90° and the two intermediate rollers 25 are lowered. The retrieval unit 21 is extended under the car towards the parking lot 4. If the retrieval unit 21 is extended the four guides and driving rollers 27' 27" in moved-together position are driven apart in direction to the wheel base and wheel track. The car is now carried by the driving rollers 27" and guided by the guide rollers 27' drawn onto the tracks 10 of the parking machine 5. After that the intermediate rollers 25 are again lowered. The retrieval unit 21 pushes the car onto the tracks 10 of the selected parking lot 4' up to the drive limit stop 13. The guide and driving rollers 27', 27" are again moved together and the last control impulse of the automatic controller installed in the parking machine 5 gives the driving motor 27 a command for retracting the retrieval unit 21, as well as the actuating impulse for the retraction of the intermediate rollers 25.
The cycle described presupposes that the lifting of table unit 20 and the parking machine 5 travel, as well as the positioning procedures, have been completed. After the cycle, the parking machine 5 is available for a new parking operation.
While the invention has been described and shown with particular reference to the preferred example, it will be apparent that variations might be possible that would fall within the scope of the present invention which is not intended to be limited, except as defined in the following claims. | An automatic high garage with a plurality of parking levels and parking spaces arranged in a circle. Within the enclosed circle are one or more automated car parking machines carrying out the parking operations. The parking spaces are constructed as pairs of outward-sloping tracks. The tracks transfer their total loads to triangularly-positioned vertical supports. A vertical column erected in the center of the high garage serves as central supporting element for the roof construction as well as for guiding the parking machines. The cars to be parked are conveyed manually and taken over by an automatic retrieval unit running under the cars. | 4 |
FIELD OF THE INVENTION
The present invention relates generally to diagnosis and study of migraine by observation of variations in the blood flow in the brain.
BACKGROUND OF THE INVENTION
It is known that many people suffer from headaches, and a significant portion suffer from migraine. A significant portion of migraine sufferers do not turn to neurology departments of medical institutions, but rather turn to their family doctor for prescription on an ad hoc basis.
Migraine is known to be diagnosed via clinical examinations and non-objective means. One objective finding known to be closely associated with migraine is variation, contraction or dilation, of blood vessels in the brain. In order to measure this, in many cases, patients are sent for MRI or CT examinations--examinations that are very costly and that often involve a long waiting time. This, of course, causes inconvenience to the patient, who also has to travel to the medical centers that have these devices, which, in many cases, are far from the patient's home.
Currently known methods involve injection of radioactive or contrast-enhancing substances into the bloodstream in order to observe and learn about variations in blood flow in the brain between migraine attacks and normal conditions. Examination is also possible by the invasive method of introducing probes (electrodes) directly into the brain.
Currently known measurement methods for measuring blood flow to and in the brain include Isotope Diagnosis (ID) and Transcranial Dopplerography (TCD). Isotope Diagnosis is invasive and can only be performed by intermittent sampling measurements, rather that continuous measurement in real-time.
Transcranial Dopplerography is noninvasive and does give real-time measurement, but it does not measure the volumetric velocity of the blood flow and does not give precise measurement of the contraction or dilation of blood vessels in the brain. It is therefore not useful for diagnosis of migraine. This imprecision results from the fact that TCD can only be used to observe a sector or large area in the brain, instead of a localized point. TCD uses ultrasound waves at a frequency of 2 MHz, which, for an estimated 15-40% of the population, do not actually reach the interior of the cranium, because of high attenuation of the ultrasound waves in the bone tissue of the cranium. In those cases, where there is a response from the skull or via "acoustic windows," such as the temporal bones (orbital regions or foramen occipital magna), the acoustic reflections detected are only from the magistrial and proximal blood vessels. In addition to these reflected signals, this method also detects reflections from the brain and from other, non-cranial, blood vessels. The result is a noisy signal which does not allow precise determination of the depth of the measurement point. This does not allow measurement of individual blood vessels or their blood flow with any precision. Use of ultrasound technology as a diagnostic tool is discussed, inter alia, in the book entitled "Textbook of Diagnostic Ultrasonography," 4 th edition, by Mosby, pages 682-686.
SUMMARY OF THE INVENTION
The present invention seeks to provide a method and device which facilitates observation in real-time of migraine activity. It is sought to accomplish this by detecting variations in cranial blood flow and observing the contraction or dilation of blood vessels in the brain. The technique used in the present invention is non-invasive and is based on objective measurement.
The present invention is based on ultrasound technology, with no injection of contrast-enhancing or any other substances into the bloodstream. The measurement results are displayed immediately, in real-time, on a computer display terminal, which allows immediate detection of changes in blood flow at a precisely defined location (i.e., position and depth) in blood vessels in the brain.
The time for the measurement with the present invention is negligible compared to the time required for the currently accepted methods of measurement. Measurement with the present invention is also less costly than currently accepted methods of measurement.
The present invention utilizes innovative application of ultrasound technology and the known reaction of different tissues to ultrasound waves for the diagnosis of changes in the system of blood vessels in the cranium (pathophysiology) in patients suffering from migraines. The present invention is based on analysis of reflected ultrasound pulses from the different structures in the intracranial space (i.e., brain, ventricles, vasales, and cysterns), their recording on magnetic media, and their immediate presentation, in real-time, on a computer display terminal.
There is thus provided, in accordance with a preferred embodiment of the invention, a method of real-time determination of variations in effective diameter of cranial blood vessels, thereby to provide an indication of migraine activity, which includes determining the blood flow rate to the brain of a subject; determining the intracranial blood flow rate in selected blood vessels; and comparing the intracranial blood flow rate with the determined blood flow rate to the brain thereby to determine a change in the intracranial blood flow rate relative to the blood flow rate to the brain, indicating a corresponding change in the effective diameter of the preselected blood vessel.
Additionally in accordance with a preferred embodiment of the invention, the method also includes the step, between the steps of determining the blood flow rate and determining the intracranial blood flow rate, of observing the pulsatile variations in the intracranial blood flow in selected blood vessels in real time, and further includes the step, between the steps of determining the intracranial blood flow rate and comparing, of analyzing the pulsatile variations in the intracranial blood flow in selected blood vessels thereby to determine changes in the effective diameter of the selected blood vessel.
Further in accordance with a preferred embodiment of the invention the steps of observing the pulsatile variations in the intracranial blood flow in selected blood vessels includes the sub-steps of exposing the head of the subject to pulses of ultrasound waves in a frequency waveband selected so as to not to be substantially attenuated by bone tissue, and such that the ultrasound energy is reflected; and detecting ultrasound waves reflected from the selected blood vessels;
and the step of determining intracranial blood flow rate further includes comparing reflected ultrasound waves with transmitted ultrasound waves in real-time, thereby to reveal pulsatile variations in the intracranial blood flow in selected blood vessels and to determine a rate of intracranial blood flow in the selected blood vessels.
Additionally in accordance with a preferred embodiment of the invention, the step of determining the blood flow rate to the brain includes detection of a reference pulse at a predetermined location upstream in the blood stream from the brain in synchronization with the step of observing pulsatile variations in the intracranial blood flow. Preferably, this is performed by employing ECG in synchronization with the step of determining the intracranial blood flow rate
Further in accordance with a preferred embodiment of the invention the step of exposing the head of the subject to pulses of ultrasound waves includes emitting ultrasound waves in the frequency range 0.5-3.0 MHz, but preferably in the range 0.8-1.2 MHz, and having a output intensity in the range 100-300 mW/cm 2 , but, in any case, not greater than 300 mW/cm 2 .
In accordance with a further embodiment of the invention, there is also provided a system for performing the above method.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be more fully understood and appreciated from the following detailed description, taken in conjunction with the drawings, in which:
FIG. 1 is a block diagram of a system for observing variations in the blood flow in the brain, constructed and operative in accordance with an embodiment of the present invention.
FIG. 2 is an illustration of a main unit of the system of the present invention, showing the primary components or modules of the system in their housing or cage.
FIGS. 3A, 3B and 3C combine to form a more detailed block diagram of the modules contained in the cage in FIG. 2.
FIGS. 3D, 3E and 3F combine to form a more detailed block diagram of the circuits performing the primary ultrasound signal processing functions, the Echo Encephalogram (ECHO-EG) and the Echo PulsoGram (EPG).
FIG. 4-A is a graphical data output display of the present embodiment of the system of the invention, obtained from a healthy subject.
FIGS. 4-B and 4-C are graphical data output displays of the present embodiment of the system of the invention, obtained from a subject suffering from migraine, for the right and left hemispheres of the brain, respectively.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, the present invention provides a system, referenced generally 100, for providing an indication of the status of cranial blood vessels, dilation or contraction, as part of the chain of causes of migraine. By measuring the rate of local blood flow in real-time at a selected location in the brain and comparing it both with a) the overall rate of blood flow to the brain, and b) the rate of local blood flow at other locations in the brain, the present invention allows determination of whether there are local increases or decreases in rate of blood flow in the brain. This indicates whether selected blood vessels in the brain are dilated or contracted, which is known to be associated with migraine activity. The determination is based on the measurement of changes in the blood vessels in the brain, which indicate deviations from known normal rate of blood flow to the brain.
The changes in the rate of blood flow in the brain are measured by transmitting ultrasound waves and detecting the reflected waves. As mentioned in the Background above, prior art attempts to use Ultrasound to observe blood flow in the brain do not provide the spatial and temporal resolution of the present invention and have the additional problems of signal attenuation and noise. These factors preclude the detailed study and precise diagnosis of migraine by means of prior art.
The present invention includes a number of factors to overcome these problems. These include using ultrasound waves transmitted in pulses at a preferred frequency of 1.0±0.2 MHz, which allows use of Ultrasound power preferably of 250±50 mW/cm 2 . The present invention includes the analysis and interpretation of the reflected pulses of ultrasound waves detected from those transmitted to the brain in a manner that provides both mean and real-time measurement of the rate of blood flow in the brain at selected locations.
Referring now to FIG. 1, it is seen that the system 100 of the present invention includes an Ultrasound probe 101, a computer 107 having an Analog to Digital (A/D) converter 106, and an Ultrasound Signal controller and processor, referenced generally 112, a Gating circuit 104, and a Electrocardiograph (ECG) 105, connected to the A/D converter 106. The system includes a suitable low-voltage power supply 109 to provide power to these circuits and a high-voltage power supply 108 to supply the Ultrasound Transmitter 113 which drives the probe 101. There are also provided a suitable display terminal 110 and printer 111, and appropriate software, as described below in conjunction with the description of computer 107. Probe 101 may be any suitable ultrasound probe for emission and detection of ultrasound waves of a frequency range of 0.5-3.0 MHz, but preferably 1.0±0.2 MHz, and having a output intensity in the range of 100-300 mW/cm2, but preferably 250±50 mW/cm2, and in any case no greater than 300 mW/cm2.
Computer 107 is provided for control of the measurement and analysis of the resulting data and may be based on any suitable microprocessor such as a 486 (or higher)-based PC. In the present embodiment of the invention, the computer 107 includes a program written to perform data collection, display, and analysis. In an alternative embodiment of the present invention, the data collection functions, which control the measurement process could be performed by a suitable dedicated microprocessor included in the Ultrasound Signal controller 112. The display and analysis program is built from two modules. A first program module displays the digital signals coming from the A/D Converter 106 which originate in the ECHO-EG 102, EPG 103, and ECG 105 circuits. A second program module allows analysis of the pulses at the specific measurement point by means of the signals from the EPG 103 and the Gating circuit 104.
These primary component circuits of the system 100 are now described in detail in conjunction with FIG. 1.
The Ultrasound Signal controller and processor 112 is responsible for generation of pulses of ultrasound waves with a frequency of 1.0±0.2 MHz, by probe 101, detection of the reflected waves or echoes, also by probe 101, and processing of the signals so detected. The reflected waves are received as one-dimensional Echo Encephalogram (ECHO-EG) 102 signals.
In the present embodiment of the invention, this Ultrasound Signal controller and processor 112 operates as follows:
The Ultrasound Transmitter 113, powered by the high-voltage power supply 108, receives a Start signal from the computer 107 via the A/D and the Gates 104. In response, it generates a series of Ultrasound pulses in the probe 101. The probe, which is typically placed at a location of interest on the head of the subject being examined, transmits the Ultrasound pulses into the head and brain of the subject and detects the Ultrasound energy reflected from various locations within the head and brain of the subject.
The reflected signal from the brain is passed by the probe 101 to the Echo Encephalogram (ECHO-EG) 102 block of the Ultrasound Signal controller and processor 112. The reflected Ultrasound pulses are received as one-dimensional digital Echo Encephalogram (ECHO-EG) 102 signals, which provides a representation of features in the head and brain of the subject along the straight line coming out of the probe 101. The ECHO-EG signal thus generated is passed to the Gating circuit and the Echo Pulsogram (EPG) block 103 of the Ultrasound Signal controller and processor 112 for further processing. The ECHO-EG signal is also passed to the A/D converter 106 in the computer 107. This is required to allow processing and presentation of the signal in digital form on the computer display 110 and for storing and recalling the data.
In the present embodiment of the invention, the Gating circuit 104 imposes a window gate on the Echo Encephalogram signal and thereby allows observation of the Ultrasound pulses reflected from a selected location in the brain in an amplified and integrated fashion. The part of the Ultrasound Signal controller and processor 112 that performs this signal processing is the Echo Pulsogram (EPG) 103 block. The EPG 103 produces a signal that represents the variation of the blood flow in the brain in real-time at the selected location. A typical resolution of the EPG circuit is 6 msec.
In the current embodiment of the invention, the Gating circuit 104, when connected to the circuits of the Ultrasound Signal controller and processor 112 and when controlled by the program in the computer 107, allows the system operator to select a location in the brain for observation and analysis.
The Electrocardiogram (ECG) 105 circuit records the pulsing of the heart muscle, in particular, the start of the pulsing, or the Systole. The present embodiment invention uses a standard ECG card, such as marketed by Aerotel™, which includes an integral power supply in the form of a nine-volt battery. In an alternative embodiment of the invention, the ECG circuit 105 receives its nine-volt supply voltage from the system power supply 109. In such a case, a protective opto-coupler (one-way electrical valve) would be included to protect the subject from this nine-volt DC voltage source.
The three analog signals produced by the present embodiment of the invention, namely, ECHO-EG, EPG, and ECG, are passed to the A/D converter 106 in the computer 107 (in the present embodiment of the invention) for transformation to digital signals for processing by the computer and for storing and recreating the signal data.
These circuits in the present embodiment of the current invention are shown in greater detail in FIGS. 3A-3F and are discussed in greater detail in relation to those figures below. The signals produced are shown as they are displayed on the display terminal 110 of the computer 107 are shown in FIGS. 4-A, 4-B, and 4-C and are discussed in relation to those figures below.
The present embodiment of the invention includes an electrical power supply 109 with an input voltage of 220 AC Volts and DC output voltages as required by the component circuits, namely, ±5 Volts and ±12 Volts and a projected embodiment of the invention includes an output of 9 Volts DC for the ECG 105. The high voltage DC power supply for the probe 101 must be a source of highly-filtered "square" DC power in the range 100-200 Volts DC.
FIG. 2 shows the housing or cage 200 for the primary component circuits for the present embodiment of the invention, namely the low-voltage power supply 109, the high-voltage power supply 108, the Ultrasound Signal controller and processor 112, the Gates 104, and the Electrocardiogram 105. Every slot in the cage 200 preferably has its own built-in noise-shielding circuit. On the rear panel of the cage are BNC connectors 202 for each circuit, which allow examination of the specific circuits functioning by means of an oscilloscope. This measurement allows matching up the digital signals with the analog signals.
The A/D Converter circuit 106 (FIG. 1) transforms the analog signals to digital signals. In the present embodiment of the invention, the circuit is located on a card in one of the slots of the computer 107. It could alternatively be housed in the cage 200 of the circuits described above.
Referring now to FIGS. 3A-3C, the major circuit blocks in FIG. 1 are seen in more detail.
With particular reference to FIG. 3C, the ECG or Electrocardiograph circuit block 105, which is included in the present embodiment of the invention, is built around an Aerotel™ model 400 Electrocardiograph circuit board 202 which is connected to the ECG electrodes 204 placed on the subject. This is supported by a voltage regulator circuit 206 to supply its required operating voltage. The ECG can be powered either by the DC power of the circuit cage 200 or by a battery. In an embodiment where the ECG power is supplied by the DC power of the circuit cage, a protective Optocoupler or one-way electrical valve circuit 208 can be included to protect the subject from the voltage source.
It is important to note the ECG signal in the present embodiment of the invention provides a reference event at a selected location upstream in the bloodstream. This establishes a reference starting time for blood flowing to the brain, which can be used to determine the rate of blood flow to the brain. The contraction of the heart muscle (Systola) detected by the ECG 105, which can be seen in the ECG signal in the example of the graphical data output display of the current system in FIG. 4-A, serves as this reference starting time. The present invention includes alternative embodiments which use any other suitably precise method of determining a reference starting time for measuring the rate of blood flow to the brain. For example, the pulse in the carotid artery, which supplies blood to the brain, could also be detected by either electrostatic (ECG) or acoustic means to serve as the required reference starting time.
The Ultrasound Signal processing circuit block 210 (FIG. 3B) is discussed in detail below with respect to FIGS. 3A-3C.
With particular reference to FIG. 3A, the Gates circuit block 104 uses methods of signal processing familiar to those versed in the art. It includes Frequency Generator circuits 212, Counter circuits 214, Timer circuits 216, and Trigger circuits 218. It chooses a segment of the actual ECHO-EG signal for integration in time to produce the EPG signal. It also includes the circuitry to display the gate on the displayed ECHO-EG signal, shown in FIG. 4-A, for example, so the operator can select a particular portion of the ECHO-EG display for EPG analysis.
FIG. 3C includes two Power Supply circuit blocks 108 and 109. The low voltage power supply 109 may be any suitable conventional power supply. The high voltage (100-200 Volts DC) supply 108 is preferably a source of highly-filtered "square" DC power, which is required for the reduction of noise in the system.
Referring now to FIGS. 3D-3F, the breakdown of the primary Ultrasound Signal processing functions, the Echo Encephalogram (ECHO-EG) 102 and the Echo Pulsogram (EPG) 103 is shown.
With particular reference to FIG. 3D, the probe 101 receives the driving ultrasound frequency (1.0±0.2 MHz) signal from the Transmitter circuit 113, which is controlled by a Start signal received from the computer 107 via the A/D Converter 106 (FIG. 1). The probe 101 also detects the reflected Ultrasound signal which is processed by the Discriminator 302, Preamplifier 304, Bandpass Filter 306, and Gain Regulator Amplifier circuits 308 in the ECHO-EG block, referenced 102, of the Ultrasound Signal Processor 112. The processed signal is modified by an Inverter 310 and a dual-diode Detector circuit 312 (FIG. 3E) and processed by a Filter circuit 314 (FIG. 3E) to produce the ECHO-EG signal for analysis and display.
With particular reference to FIG. 3D, the ECHO-EG signal is then amplified by an Amplifier circuit 316 and then the Gate 104 for the display (See description of FIG. 4-A below) is added by an Echo Gate Switch circuit 318, Echo Gate Integrator circuit 320, and Marker Signal Switch circuit 322. With particular reference to FIG. 3D, the unamplified ECHO-EG signal is also routed to the circuits of the EPG 103, which, based on the signal from the Gate circuit 104 process a portion of the ECHO-EG curve to produce the EPG curve. The EPG includes a Pulse Gate circuit 324, the Pulse Gate Integrator circuit 326, and a pair of Lowpass Filter circuits 328 and 330 which produce the EPG signal for analysis and display. They are preferably arranged as shown in FIG. 3F.
The significance of two signals, ECHO-EG and EPG, together with the Gate 104 are explained below with respect to FIG. 4-A, which is an example of a the graphical data output display produced by the present embodiment of the invention. These signals are digitized by an A/D Converter 106 circuit for storage, analysis, and display by the computer 107.
As was pointed out above, with respect to FIG. 2, the A/D Converter circuit 106, which transforms the analog signals to digital signals, is located, in the present embodiment of the invention, on a card in one of the slots of the computer 107. It could also be housed in the cage 200 of the special circuits described above.
FIGS. 4-A, 4-B, and 4-C are printouts of examples of graphical data output display obtained with the present embodiment of a system according to this invention as displayed on the display terminal of the computer 107. The displays each include three signals: the Echo Encephalogram (ECHO-EG) signal, the Echo Pulsogram (EPG) signal, and the Electrocardiograph (ECG) signal, which are described below. FIG. 4-A represents data obtained from a healthy subject. FIGS. 4-B and 4-C represent data obtained from a subject diagnosed independently to be suffering from migraine, for the right and left hemispheres of the brain, respectively.
The three signals graphically represented in each figure are used by the present invention to characterize the blood flow in the brain. The signals, as shown in FIG. 4-A, are as follows:
The Echo Encephalogram (ECHO-EG) signal 401 graphically shows modulation in the reflected ultrasound waves detected when ultrasound waves are transmitted through the cranium to blood vessels in the brain. The modulation is a function of time from the transmission of the signal and bears a one-to-one relationship with the depth of the point of reflection. This means the ECHO-EG signal 401 is a representation of features in the head and brain of the subject along the straight line coming out of the probe 101 (FIG. 1). The gate 418 superimposed on the ECHO-EG signal indicates the specific portion of the curve being observed in the Echo Pulsogram (EPG) signal, which corresponds to the location in the brain selected for observation.
The Echo Pulsogram (EPG) signal 402 graphically shows modulation of the total (integrated) detected ultrasound signal from the area selected by the gate on the ECHO-EG signal 401 as a function of time. This signal 402 provides a measure in real-time of the condition of the blood vessels (contraction or dilation) represented by the selected area in the ECHO-EG signal 401. The EPG signal 402 is displayed in the same units of amplitude as the ECHO-EG signal 401.
The Electrocardiograph (ECG) signal 403 presents graphically modulation of the signal from the heart muscle as a function of time. This signal shows the start (Systola) and other details of each heartbeat in real-time.
The time units of the horizontal axes are the same for the EPG signal 402 and ECG signal 403, but not for the ECHO-EG signal 401.
Descriptions of additional details shown on the data output display are as follows:
In FIG. 4-A, Point C1 on the graph of the ECG signal 403 is the starting time of the Systola of the heart. Point P1 on the graph of the EPG signal 402 is the starting time for the pulse in the selected blood vessel in the brain.
The time interval 413 between points C1 and P1 represents the time for blood to flow from the heart to the brain, which is also the delay between the ECG and Echo-PG signals. This interval is called tau (τ). In the example pictured in FIG. 4-A, the time τ is 211 msec.
The depth of the measurement point is displayed in the box 414 labeled "Gate Depth" in the upper right of the graph 414. This point corresponds to the point in the ECHO-EG signal graph selected by the gate 418. In this case, the Gate Depth is 72.93 mm. This point is labeled on the graph as point E1.
Looking at that part of the graph of the ECHO-EG signal 401 enclosed by the gate 418, there are two peaks A1 and A2 shown at the same point, referenced E1, in the signal graph. The peaks A1 and A2 represent a blood vessel in the brain in the respective states of Diastole and Systole. Looking now at the graph of the EPG signal 402, which is the reflected Ultrasound signal in the area enclosed by the gate 418 as a function of time, these two points are the respective minimum and maximum points, 426 and 427, of the EPG signal 402. The rise time and fall time of this signal represents the rise time and fall time of the pulse in the blood vessel in the brain. The shape of the EPG waveform 402 indicates the status of the blood vessel and can be used to deduce the presence of migraine activity. This representation is the usual one for this type of graph.
For the typical, healthy, population, the time for blood to flow from the heart to the brain is 211±6 msec.
Note also that the examination point on the skull is indicated on the pictographs 419 above the graph.
In FIG. 4-B, the data is for a subject suffering from migraine, right side of brain. The time interval 423 between points C1 and P1 is 240 msec at a depth of 65.25 mm. This reading indicates a contraction of the blood vessels in this part of the brain, since the time for blood to flow to the brain is longer than average.
In FIG. 4-C, the data is for a the same subject suffering from migraine, left side of brain. The time interval 433 between points C1 431 and P1 432 is 150 msec at a depth of 65.25. This reading indicates a dilation of the blood vessels in this part of the brain, since the time for blood to flow to the brain is shorter than average.
As indicated above, the normal time for blood to flow from the heart to the brain is 211±6 msec.
The significance of the data presented in the EPG signal graphs in FIGS. 4-B and 4-C is that there is an asymmetry in the speed of the blood flow to the two hemispheres of the brain. Very often the dilation of the blood vessels in one hemisphere of the brain is a result of compensation by that part of the brain in reaction to contraction of the blood vessels in the other hemisphere of the brain. This asymmetry is indicative of migraine.
It will be appreciated by persons skilled in the art, that the scope of the present invention is not limited by what has been specifically shown and described hereinabove, merely by way of example. Rather, the scope of the present invention is defined solely by the claims, which follow. | A method of real-time determination of variations in effective diameter of cranial blood vessels, thereby to provide an indication of migraine activity, which includes determining the blood flow rate to the brain of a subject; determining the intracranial blood flow rate in selected blood vessels; and comparing the intracranial blood flow rate with the determined blood flow rate to the brain thereby to determine a change in the intracranial blood flow rate relative to the blood flow rate to the brain, indicating a corresponding change in the effective diameter of the preselected blood vessel. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims the benefit under 35 USC 119(e) of U.S. provisional application No. 61/142,543, filed Jan. 5, 2009, the contents of which are herein incorporated by reference.
FIELD OF THE INVENTION
This invention relates to the field of microelectromechanical systems (MEMS), and in particular a method of making MEMS devices for biomedical applications (BIOMEMS).
BACKGROUND OF THE INVENTION
Biomems devices are used in the medical field for the analysis of fluids. For this purpose, there is a need to construct such devices containing micro-channels. Various prior art techniques for fabricating such channels are known.
Various Prior Art references related to the fabrication of micro-channels. Examples of such techniques are described in the following patents: U.S. Pat. No. 6,186,660 “ ” Microfluidic systems incorporating varied channel dimensions>>; U.S. Pat. No. 6,180,536 <<Suspended moving channels and channel actuators for . . . >>; U.S. Pat. No. 6,174,675 <<Electrical current for controlling fluid parameters in . . . >>; U.S. Pat. No. 6,172,353 <<System and method for measuring low power signals>>; U.S. Pat. No. 6,171,865 <<Simultaneous analyte determination and reference . . . >>; U.S. Pat. No. 6,171,850 <<Integrated devices and systems for performing . . . >>; U.S. Pat. No. 6,171,067 <<Micropump>>; U.S. Pat. No. 6,170,981 <<In situ micromachined mixer for microfluidic analytical . . . >>; U.S. Pat. No. 6,167,910 <<Multi-layer microfluidic devices>>; U.S. Pat. No. 6,159,739 <<Device and method for 3-dimensional alignment of . . . >>; U.S. Pat. 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The following published paper shows the Prior Art concerning a polydimethylsiloxane (PDMS) biochip capable of capacitance detection of biological entities (mouse cells): L. L. Sohn, O. A. Saleh, G. R. Facer, A. J. Beavis, R. S. Allan, and D. A. Notterman, ‘Capacitance cytometry: Measuring biological cells one by one’, Proceedings of the National Academy of Sciences (USA), Vol. 97, No. 20, Sep. 26, 2000, pp. 10687-10690
The above prior art USA patents show that passive micro-channel biochip devices are fabricated using fusion bonding of a combination of various substrates, such as: acrylonitrile-butadiene-styrene copolymer, polycarbonate, polydimethylsiloxane (PDMS), polyethylene, polymethylmethacrylate (PMMA), polymethylpentene, polypropylene, polystyrene, polysulfone, polytetrafluoroethylene (PTFE), polyurethane, polyvinylchloride (PVC), polyvinylidine fluoride (PVF). These Prior Art USA patents show that mechanical stamping or thermal forming techniques are used to define a network of micro-channels in a first substrate prior its fusion bonding to another such substrate, as to form microchannels between the two bonded substrates. The result is a simple passive micro-channel biochip device which can be patterned with conductive layers as to connect an external processor used to provoke fluid movement by electrophoresis or electroosmosis, analysis and data generation. An example of such passive micro-channel biochip devices obtained from the fusion of such polymeric substrates is disclosed in U.S. Pat. No. 6,167,910 <<Multi-layer microfluidic devices>>.
These Prior Art USA patents also indicate that passive micro-channel biochip devices can be fabricated from the combination of various micro-machined silica or quartz substrates. Again, assembly and fusion bonding is required. The result is again a simple passive biochip device which can be patterned with conductive layers as to connect an external processor used to provoke fluid movement by electrophoresis or electroosmosis, analysis and data generation. An example of such passive micro-channel biochip devices obtained from the fusion of such silica substrates is disclosed in U.S. Pat. No. 6,131,410 <<Vacuum fusion bonding of glass plates>>.
These Prior Art USA patents also indicate that passive micro-channel biochip devices can be fabricated from a passive micro-machined silicon substrate. In that case, the silicon substrate is used as a passive structural material. Again, assembly and fusion bonding of at least two sub-assemblies is required. The result is again a simple passive biochip to connect to an external processor used to provoke fluid movement, analysis and data generation. An example of such passive micro-channel biochip devices obtained from a passive micro-machined silicon substrate is disclosed in U.S. Pat. No. 5,705,018 <<Micromachined peristaltic pump>>.
These Prior Art USA patents also indicate that active micro-reservoir biochip devices can be fabricated from machining directly into an active silicon substrate. In that case, the control electronics integrated in the silicon substrate is used as an active on-chip fluid processor and communication device. The result is a sophisticated biochip device which can perform, into pre-defined reservoirs, various fluidics, analysis and (remote) data communication functions without the need of an external fluid processor in charge of fluid movement, analysis and data generation. An example of such active micro-reservoir biochip devices obtained from an active micro-machined silicon substrate is disclosed in U.S. Pat. No. 6,117,643 <<Bioluminescent bioreporter integrated circuit These Prior Art references also indicate that passive polydimethylsiloxane (PDMS) biochips have been developed for the detection of biological entities using gold coated capacitor electrodes. An example of such passive polydimethylsiloxane (PDMS) biochips with gold electrodes is disclosed in the paper by L. L. Sohn, O. A. Saleh, G. R. Facer, A. J. Beavis, R. S. Allan, and D. A. Notterman, ‘Capacitance cytometry: Measuring biological cells one by one’, Proceedings of the National Academy of Sciences (USA), Vol. 97, No. 20, Sep. 26, 2000, pp. 10687-10690).
These Prior Art references also indicate that wax has been used to fabricate such microchannels. This process requires the top covers of the microchannels to be first bonded to a carrier wafer using a low temperature wax. Then, a photosensitive benzocyclobutene, BCB, is spun-on, exposed and developed as to define the sidewalls of the microchannels. Then the photodefined BCB of the carrier wafer is properly aligned and bonded to a receiving wafer integrating the bottoms of the microchannels. Then the wax of the carrier wafer is heated above its melting point as to detach the BCB bonded sidewalls and covers of the carrier wafer onto the bottoms of the receiving wafer, thus creating microchannels. An example of such an approach in shown A. Jourdain, X. Rottenberg, G. Carchon and H. A. C. Tilmanstitled, ‘Optimization of 0-Level Packaging for RF-MEMS Devices’, Transducers 2003, The 12th International Conference on Solid State Sensors, Actuators and Microsystems, Boston, Jun. 8-12, 2003, pp. 1915-1918
These Prior Art references also indicate that parylene could be used to fabricate such microchannels. A carrier wafer could be first coated with 1.3 um of AZ1813 sacrificial photoresist over which a 0.38 um thick layer of parylene could be deposited and patterned to expose the underlying layer of parylene. Following local etch of the exposed parylene the underlying sacrificial photoresist could be dissolved in acetone to leave an array of free-standing parylene covers on the carrier wafer. The patterned receiving wafer integrating the sidewalls and bottoms of the microchannels could be coated with another layer of 0.38 um thick layer of parylene, could be aligned and could be pressed against the free standing pattern of parylene on the carrier wafer while heating at 230° C. under a vacuum of 1.5*10 −4 Torr. The two parylene layers could polymerize together and would result in bond strength of 3.6 MPa. An example of such an approach in shown in the paper by H. S. Kim and K. Najafi, ‘Wafer Bonding Using Parylene and Wafer-Level Transfer of Free-Standing Parylene Membranes’, Transducers 2003, The 12th International Conference on Solid State Sensors, Actuators and Microsystems, Boston, Jun. 8-12, 2003, pp. 790-793
U.S. patent application No. 60/894,930, Mar. 15, 2007 describes a BioMEMS fabrication process that uses a temporary adhesion layer made of silicon nitride exposed to anhydrous hydrofluoric acid as the temporary adhesion layer.
SUMMARY OF THE INVENTION
Accordingly the present invention provides a method of making a MEMS device comprising forming a self-aligned monolayer (SAM) on a carrier wafer; forming a first polymer layer on said self-assembled monolayer; patterning said first polymer layer to form a microchannel cover; bonding said microchannel cover to a patterned second polymer layer on a device wafer to form microchannels; and releasing said carrier wafer from the first polymer layer.
The present invention thus provides a novel, simple, inexpensive, high precision, gold-free, sodium-free and potassium-free process allowing the formation, at a temperature of less than 250° C., of hundreds if not thousands of microfluidics microchannels on a CMOS wafer integrating hundreds if not thousands of digital and/or analog CMOS control logic and/or high voltage CMOS drivers capable of performing sensing and/or microfluidics actuation functions. This novel BioMEMS fabrication process uses a hydrophobic self-aligned monolayer, SAM, (also known as a self-assembled monolayer) as a temporary adhesion layer between a carrier wafer and the hundreds if not thousands of photolithographically defined microfluidic microchannels to be transferred onto the Device Wafer integrating hundreds if not thousands of digital and/or analog CMOS control logic and/or high voltage CMOS drivers capable of performing sensing and/or microfluidics actuation functions.
The SAM monolayer provides a strong bond during manufacture of the MEMS device to permit the carrier and device wafers to be bonded together, while providing an easy release of the carrier wafer from the device wafer after the two components have been bonded together.
While the carrier wafer I one embodiment is a silicon carrier wafer, it could also be a glass carrier wafer, a compound semiconductor carrier wafer, a ceramic carrier wafer, or a metal carrier wafer.
The SAM coating may be (Tridecafluoro-1,1,2,2-tetrahydrooctyl)trichlorosilane, C 8 H 4 Cl 3 F 13 Si (FOTS), dimethyldichlorosilane (DDMS); coating is tridecafluoro-1; or heptadecafluoro-1,1,2,2-tetrahydrodecyltrichlorosilane (FDTS).
The first polymer layer may be a photopolymer, preferably a negative tone photopolymer, and more preferably an epoxy-like negative tone photopolymer such as one of the NANO SU-8 series from MicroChem Corporation, namely SU-8 2005; SU-8 2010; SU-8 2025; SU-8 2050; SU-8 2100.
Alternatively, the epoxy-like negative tone photopolymer may be one of the GM or GLM SU-8 series from Gerstel Ltd, such as GM1040; GM1060; GM1070, GLM2060, GLM3060.
The epoxy-like negative tone photopolymer can also be one of the XP KMPR-1000 SU8 series from Kayaku Microchem Corporation, such as XP KMPR-1005; XP KMPR-1010; XP KMPR-1025; XP KMPR-1050; XP KMPR-1100.
The device wafer may contain a combination of two sublayers of photopolymers, where the first and second photopolymers are also a negative tone photopolymer, and in particular an epoxy-like negative tone photopolymer of the type listed above.
The photopolymer on the carrier wafer is preferably about 20 um thick, although the thickness may range between 5 um and 500 um.
The first and second photopolymer sublayers on the device wafer are preferably about 10 um thick, although the thickness may range between 5 um and 500 um.
The photopolymer of course should be strong enough to provide a cover of microchannels.
The combination of two layers of photopolymer sublayers on the device wafer should be strong enough to become the sidewalls and bottoms of microchannels.
The photopolymer is typically exposed using a UV source, preferably a broadband UV source (g-line, h-line and l-line), where broadband UV source is highly collimated to achieve high aspect ratio features.
The device wafer may contain more than two sublayers of photopolymers to produce more than one level of micro-channels.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings, in which:
FIG. 1A is glazing angle αicture of the contact angle of water droplets on a virgin silicon wafer not covered with a SAM coating;
FIG. 1B is glazing angle picture of the contact angle of water droplets on a virgin silicon wafer covered with a SAM coating;
FIG. 2 shows the chemical structure of (Tridecafluoro-1,1,2,2-tetrahydrooctyl)trichlorosilane, C 8 H 4 Cl 3 F 13 Si;
FIG. 3 shows The self-alignment of (Tridecafluoro-1,1,2,2-tetrahydrooctyl)trichlorosilane, C 8 H 4 Cl 3 F 13 Si, onto a silicon wafer resulting from the ‘SAM treatment’ before ‘Post-SAM treatment’;
FIG. 4 shows the surface condition of a silicon wafer after being exposed to standard atmospheric conditions. Layers of water molecules are adsorbed onto the silicon surface due to hydrogen van der Waals bonds;
FIG. 5 shows the surface condition of a silicon wafer after being vacuum dehydrated at about 150° C. for about 60 minutes followed by an air exposure of less then about two hours prior to the SAM coating;
FIG. 6 shows the chemical reactions involved in the self-alignment of (Tridecafluoro-1,1,2,2-tetrahydrooctyl)trichlorosilane, C 8 H 4 Cl 3 F 13 Si, onto dehydrated and air exposed silicon wafers;
FIG. 7 shows the cross-linking chemical reactions involving the side hydrogen atoms present at the tip of the C 8 H 4 Cl 3 F 13 Si molecules;
FIGS. 8A to 8E show steps in the manufacture of a carrier wafer;
FIGS. 9A to 9E show steps in the manufacture of a device wafer; and
FIGS. 10A to 10C show the final assembly steps of the carrier and device wafers.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The glazing angle pictures shown in FIGS. 1A and 1B were taken by a Kruss G10/DSA10 Drop Shape Analysis System and the contact angle of water droplets onto a virgin silicon wafer not covered by the SAM coating ( FIG. 1A ) and of the contact angle of water droplets onto a virgin silicon wafer covered by the SAM coating ( FIG. 1 b ). The increased contact angle of about 108° clearly shows the hydrophobic nature of the SAM coating.
FIG. 2 shows the chemical structure of (Tridecafluoro-1,1,2,2-tetrahydrooctyl)trichlorosilane, C 8 H 4 Cl 3 F 13 Si and its surface organization when self-aligned onto a silicon wafer. FIG. 3 shows the self-alignment of (Tridecafluoro-1,1,2,2-tetrahydrooctyl)trichlorosilane, C 8 H 4 Cl 3 F 13 Si, onto a silicon wafer resulting from the SAM coating. FIG. 4 shows the surface condition of a silicon wafer after being exposed to standard atmospheric conditions. Layers of water molecules are adsorbed onto the silicon surface due to hydrogen van der Waals bonds. These layers need to be removed by a mild vacuum heat treatment prior to the application of the SAM coating. A typical processing condition is a vacuum dehydratation at about 150° C. for about 60 minutes followed by an air exposure of less than about two hours prior to the SAM coating.
FIG. 4 shows the surface condition of a silicon wafer after being vacuum dehydrated at about 150° C. for about 60 minutes followed by an air exposure of less than about two hours prior to the SAM coating.
Following the loading of the dehydrated and air exposed silicon wafers into the vacuum chamber used for the ‘SAM treatment’, a series of vacuum pump-downs and dry nitrogen back-fills allow the elimination of the residual oxygen and water vapour present in the atmospheric ambient around the wafers during the loading process. Following one of the pump-down, a bleeding valve is opened as to allow vapours of (Tridecafluoro-1,1,2,2-tetrahydrooctyl)trichlorosilane, C 8 H 4 Cl 3 F 13 Si, to enter the vacuum chamber at a temperature of about 40° C. Pump-down is again performed as to eliminate HCl by-products resulting from the ‘SAM treatment’. The bleeding valve is again opened as to perform another cycle, and so on. The number of cycles is load dependant and requires to be increased depending upon the surface area of silicon to be treated. A filan pump-down followed by a nitrogen purge is used to un-load the ‘SAM treated’ silicon wafers.
FIG. 6 shows the chemical reactions involved in the self-alignment of (Tridecafluoro-1,1,2,2-tetrahydrooctyl)trichlorosilane, C 8 H 4 Cl 3 F 13 Si, onto dehydrated and air exposed silicon wafers. Hydrogen chloride is produced from the chemical reaction of the chlorine atoms residing at the tip of the C 8 H 4 Cl 3 F 13 Si molecules and the hydrogen atoms present at the surface of the dehydrated and air exposed silicon wafers. The resulting surface is the one shown FIG. 3 .
Following the ‘SAM treatment’, wafers are loaded in the ‘Post-SAM treatment’ system shown to perform the cross-linking chemical reaction that result in a dense SAM coating with good adhesion to the silicon substrate. This process involves the elimination of molecular hydrogen gas and results in a dense hydrophobic SAM coating. FIG. 7 shows the cross-linking chemical reaction involving the side hydrogen atoms also present at the tip of the C 8 H 4 Cl 3 F 13 Si molecules and shows how each C 8 H 4 Cl 3 F 13 Si molecule is attached to each other with high energy double covalent ‘C═C’ bonds. These extremely strong ‘C═C’ covalent bonds coupled with the very strong ‘C—Si’ covalent bonds to the silicon substrate result in the observed excellent adhesion.
In order to produce a MEMS device in accordance with one embodiment of the invention, a SAM coating 12 is first deposited onto the carrier wafer 10 as shown in FIGS. 8A and 8B .
Next a 20 um thick layer 14 of photopolymer is applied by spinning directly onto the SAM coating ( FIG. 8C ). The thickness of this first layer is adjusted in such a way that it will be strong enough to be used as cover of the microchannel. Following proper dispensing, spinning and solidification by partial solvents evaporation, the dried photopolymer is subjected to a pre-exposure bake not exceeding 95° C. to drive-off more of its residual solvents in preparation for the exposure to ultra-violet light through a suitably designed mask.
FIG. 8D shows that this 20 um thick layer of photopolymer is exposed to ultraviolet light through the openings 16 of the mask 18 defining the shape of the cover of the microchannel. Being of negative tone, the photopolymer will reticulate in the regions exposed to the ultraviolet light and will locally become resistant to the chemical attack of the developer to be used later in the process. Following ultraviolet light exposure for an optimized dose, this first layer of a thick negative tone photopolymer is subjected to a post-exposure bake again not exceeding 95° C. to drive-off more of the residual solvents and the chemical by-products formed by the ultra-violet light exposure.
FIG. 8E shows that this 20 um thick layer of photopolymer is developed, thus defining the cover of the microchannel. The regions of the photopolymer that have being exposed to the ultraviolet light passing through the openings of the mask remain intact because resistant to the chemical attack of the developer. Following suitable development of the photopolymer, the resulting photopolymer patterns are subjected to a post-develop bake again not exceeding 95° C. to drive-off more of the residual solvents and the chemical by-products formed by the ultra-violet light exposure and by the developer. At this point, the developed and baked photopolymer patterns of the carrier wafer are ready to be flipped over and aligned to the device wafer.
FIG. 9A shows the silicon wafer 20 used as device wafer substrate.
A 10 um thick layer 22 of photopolymer is applied by spinning as shown in FIG. 9B . This layer 22 is to become the bottom of the microchannel. Following proper dispensing, spinning and solidification by partial solvents evaporation, the dried photopolymer is subjected to a high temperature bake to drive-off its residual solvents and to allow the photopolymer to be stabilized i.e. to become chemically stable when an upper layer of photopolymer will be spun-on and exposed in a further step.
A second layer 24 of a 10 um thick negative tone photopolymer is then applied by spinning onto the exposed first layer of a thick negative tone photopolymer as shown in FIG. 9C . This second layer 24 is to become the sidewall of the microchannel. The thickness of this second layer is adjusted in such a way that it will form tall enough microchannels confined between the already stabilized bottom layer of the device wafer and the top layer yet to be transferred from the carrier wafer. Following proper dispensing, spinning and solidification by partial solvents evaporation, the dried photopolymer is subjected to a pre-exposure bake not exceeding 95° C. to drive-off more of its residual solvents in preparation for the exposure to ultra-violet light through a suitably designed mask;
This second layer 24 of 10 um thick negative tone photopolymer is exposed to ultraviolet light through the openings of the mask as shown in FIG. 9D . Being of negative tone, the photopolymer will reticulate in the regions exposed to the ultraviolet light and will locally become resistant to the chemical attack of the developer to be used later in the process. Following ultraviolet light exposure for an optimized dose, this second layer of a thick negative tone photopolymer is subjected to a post-exposure bake again not exceeding 95° C. to drive-off more solvents and chemical by-products formed by the ultra-violet light exposure.
FIG. 9E shows that this second layer 22 of a suitably exposed 10 um thick negative tone photopolymer is developed into a proper developer, thus defining the shape of the microchannels. The regions of the photopolymer that have being exposed to the ultraviolet light passing through the openings of the mask remain intact because resistant to the chemical attack of the developer. Following suitable development of the photopolymer, the resulting photopolymer patterns are subjected to a post-develop bake again not exceeding 95° C. to drive-off more of the residual solvents and the chemical by-products formed by the ultra-violet light exposure and by the develop. At this point, the developed and baked photopolymer patterns of the Device Wafer are ready to be aligned and to receive the transferred top photopolymer layer of the carrier wafer
FIG. 10A shows that the carrier wafer supporting the developed and baked photopolymer patterns defining the cover of the microchannel is flipped-over and properly aligned to the Device Wafer integrating the sidewall and bottom of the microchannel. The precise alignment is such that the aligned wafers, not yet in physical contact, are kept in position using a special fixture in preparation for loading of the pair of wafers into a wafer bonding equipment.
FIG. 10B shows the pair of properly aligned wafers ready to be loaded into wafer bonding equipment that allows these to become in physical contact by pressing one against the other without losing alignment accuracy. The pair of wafers is then heated, under vacuum, to a temperature of about 120-150° C. while maintaining the two wafers under intimate contact, as to provoke the bonding of the photopolymer of the carrier wafer to the exposed photopolymer of the device wafer. Following proper baking at a temperature of about 120-150° C. while maintaining the two wafers under intimate contact, the pair of wafers is unloaded from the wafer bonding equipment and the two wafers are separated.
FIG. 10C shows that the MEMS device after separation of the two wafers. The separation is possible due to the hydrophobic nature of the SAM coating. This wafer separation can be performed using an EVG-850 DB wafer debonder.
The device now incorporating the microchannels 26 is heated under vacuum at more than 200° C. as to chemically stabilize the photopolymer and as to achieve a solid permanent microchannel.
Embodiments of the invention thus provide a novel, simple, inexpensive, high precision, gold-free, sodium-free and potassium-free process allowing the formation, at a temperature of less than 250° C., of hundreds if not thousands of microfluidics microchannels on a CMOS wafer integrating hundreds if not thousands of digital and/or analog CMOS control logic and/or high voltage CMOS drivers capable of performing sensing and/or microfluidics actuation functions. This new BioMEMS fabrication process uses an hydrophobic self-aligned monolayer, SAM, as temporary adhesion layer between a Carrier Wafer and the hundreds if not thousands of photolithographically defined microfluidics microchannels to be transferred onto the Device Wafer integrating hundreds if not thousands of digital and/or analog CMOS control logic and/or high voltage CMOS drivers capable of performing sensing and/or microfluidics actuation functions.
The silicon wafer used as the carrier wafer is preferably a SEMI standard 150 mm diameter silicon wafer but could also be a 100 mm diameter, a 200 mm diameter or a 300 mm diameter silicon wafer.
The preferred 20 um thick layer 14 of a negative tone photopolymer is applied by spinning onto the SAM coating. Such a preferred photopolymer is SU-8, a negative tone epoxy-like near-UV photoresist developed by IBM and disclosed in U.S. Pat. No. 4,882,245 entitled: ‘Photoresist Composition and Printed Circuit Boards and Packages Made Therewith’. This high performance photopolymer is available from three companies: MicroChem Corporation, a company previously named Microlithography Chemical Corporation, of Newton, Mass., USA. The photopolymer is sold under the name NANO SU-8 at different viscosities: SU-8 2005; SU-8 2010; SU-8 2025; SU-8 2050; SU-8 2100; Gerstel Ltd, a company previously named SOTEC Microsystems, of Pully, Switzerland. The photopolymer is sold under the name GM or GLM at different viscosities: GM1040; GM1060; GM1070, GLM2060, GLM3060; and Kayaku Microchem Corporation (KMCC), of Chiyoda-Ku, Tokyo, Japan. The photopolymer is sold under the name XP KMPR-1000 SU8 at different viscosities: XP KMPR-1005; XP KMPR-1010; XP KMPR-1025; XP KMPR-1050; XP KMPR-1100.
This high performance photopolymer may be spin coated using one of the two coat stations of an EV Group Hercules processor. About 3 ml of Microchem SU-8 2025 photopolymer solution is dispensed above the 150 mm wafer before spinning at about 1600 RPM as to dry the spin-on photopolymer by partial solvents evaporation and as to achieve a film thickness of preferably 20 um to be strong enough to become the protection capsule. The dried photopolymer is subjected to a pre-exposure bake not exceeding 95° C. and for about 8 to 10 minutes as to drive-off more of its residual solvents. This MicroChem SU-8 2025 negative tone photopolymer can alternately be replaced by the Gerstel GM 1060 or GLM2060 negative tone photopolymer or by the Kayaku Microchem XP KMPR 1025 negative tone photopolymer to achieve the same preferred thickness of 20 um. The viscosity of the photopolymer solution could be lower than the one of the Microchem SU-8 2025 photopolymer solution as to reduce the thickness of this first layer of negative tone photopolymer from 40 um down to about 5 um. In that case, the Microchem SU-8 2005 or SU-8 2010 negative tone photopolymer solution could be used, the Gerstel GM 1040 negative tone photopolymer solution could be used, or the Kayaku Microchem XP KMPR 1005 or XP KMPR-1010 negative tone photopolymer solution could be used. Alternately, the viscosity of the photopolymer solution could be higher than the one of the Microchem SU-8 2025 photopolymer solution as to increase the thickness of this first layer of negative tone photopolymer from 20 um up to about 500 um. In that case, the Microchem SU-8 2050 or SU-8 2100 negative tone photopolymer solution could be used, the Gerstel GM 1070 negative tone photopolymer solution could be used, or the Kayaku Microchem XP KMPR 1050 or XP KMPR-1100 negative tone photopolymer solution could be used. To thicker negative tone photopolymer layers should be associated a longer than 90 seconds pre-exposure bake but still not exceeding 95° C. and for about as to drive-off the residual solvents.
FIG. 8D shows that this preferably 20 um thick layer of negative tone photopolymer is exposed using the highly collimated broadband UV source (g-line, h-line and l-line) of the EV Group Hercules processor through the openings of the mask defining the shape of the protection capsule. Being of negative tone, the photopolymer will reticulate in the regions exposed to the ultraviolet light and will locally become resistant to the chemical attack of the developer to be used later in the process. Following ultraviolet light exposure for an optimized dose of about 180 mJ/cm 2 , this first layer of a thick negative tone photopolymer is subjected to a 5 minutes duration post-exposure bake again not exceeding 95° C. as to drive-off more of the residual solvents and the chemical by-products formed by the ultra-violet light exposure. At this point, the exposed photopolymer is not yet developed. Again, if this MicroChem SU-8 2025, Gerstel GM 1060 or GLM2060 or Kayaku Microchem XP KMPR 1025 negative tone photopolymer is replaced by a lower viscosity solution such as the Microchem SU-8 2005 or SU-8 2010, the Gerstel GM 1040 or the Kayaku Microchem XP KMPR 1005 or XP KMPR-1010 negative tone photopolymer solution, then the optimized dose would be lower than about 310 mJ/cm 2 , as to prevent over-exposure of this first layer of a negative tone photopolymer. Alternatively, if this MicroChem SU-8 2025, Gerstel GM 1060 or GM 2060 or Kayaku Microchem XP KMPR 1025 negative tone photopolymer is replaced by a higher viscosity solution such as the Microchem SU-8 2050 or SU-8 2100, the Gerstel GM 1070 or the Kayaku Microchem XP KMPR 1050 or XP KMPR-1100 negative tone photopolymer solution, then the optimized dose would be higher than about 310 mJ/cm 2 , as to prevent under-exposure of this first layer of a negative tone photopolymer. To thicker negative tone photopolymer layers should also be associated a longer than 90 seconds post-exposure bake but still not exceeding 95° C.
FIG. 8E shows that this preferably 20 um thick layer of MicroChem SU-8 2025 negative tone photopolymer is developed using one of the two develop stations of the EV Group Hercules processor to define an array of covers to be transferred onto the array of microchannels of another substrate. The regions of the photopolymer that have being exposed to the ultraviolet light passing through the openings of the mask remain intact because resistant to the chemical attack of the developer. This layer of negative tone photopolymers is capable of achieving complex structures and mechanical features having a height:width aspect ratio as high as 10:1.
FIG. 9A shows the silicon wafer used as Device Wafer substrate. This silicon wafer is preferably a SEMI standard 150 mm diameter silicon wafer but could also be a 100 mm diameter, a 200 mm diameter or a 300 mm diameter silicon wafer;
FIG. 9B shows that a first layer of a preferably 10 um thick layer negative tone photopolymer is applied by spinning. This first layer is to become an array of bottoms of the array of microchannels. This negative tone photopolymer is spin coated using one of the two coat stations of the EV Group Hercules processor. Again, about 3 ml of Microchem SU-8 2005 is dispensed above the 150 mm wafer before spinning at about 1600 RPM as to dry the spin-on photopolymer by partial solvents evaporation and as to achieve a film thickness of preferably 10 um. The dried photopolymer is subjected to a pre-exposure bake not exceeding 95° C. and for about 5 minutes as to drive-off more of its residual solvents. This MicroChem SU-8 2005 negative tone photopolymer can alternately be replaced by the MicroChem SU-8 2010, the Gerstel GM 1040 or the Kayaku Microchem XP KMPR 1005 or XP KMPR 1010 negative tone photopolymer to achieve the same preferred thickness of 10 um. The viscosity of the photopolymer solution could be higher than the one of the MicroChem SU-8 2005 photopolymer solution as to increase its thickness above 10 um. In that case, the Microchem SU-8 2025 or SU-8 2050 or SU-8 2100, the Gerstel GM 1060, GM 1070 or GM 2060 or the Kayaku Microchem XP KMPR 1025, XP KMPR 1050 or XP KMPR-1100 negative tone photopolymer solution could be used. Again, to thicker negative tone photopolymer layers should be associated a longer than 90 seconds pre-exposure bake at about 95° C. as to drive-off more of its residual solvents. A vacuum bake at a temperature of about 180° C. is performed for about 2 hours to stabilize this first 10 um thick layer and prevent its photochemical activity when exposed to ultra-violet light.
FIG. 9C shows that a second layer of a preferably 10 um thick negative tone photopolymer is applied by spinning onto the thermally stabilized 10 um thick negative tone photopolymer. Again, this high performance photopolymer is spin coated using one of the two coat stations of the EV Group Hercules processor. Again, about 3 ml of Microchem SU-8 2005 is dispensed above the 150 mm wafer before spinning at about 1600 RPM as to dry the spin-on photopolymer by partial solvents evaporation and as to achieve a 10 um thick film. The dried photopolymer is subjected to a pre-exposure bake not exceeding 95° C. and for about 5 minutes as to drive-off more of its residual solvents. This MicroChem SU-8 2005 negative tone photopolymer can alternately be replaced by the MicroChem SU-8 2010, the Gerstel GM 1040 or the Kayaku Microchem XP KMPR 1005 or XP KMPR 1010 negative tone photopolymer to achieve the same preferred thickness of 10 um. The viscosity of the photopolymer solution could be higher than the one of the MicroChem SU-8 2005 photopolymer solution as to increase its thickness above 10 um. In that case, the Microchem SU-8 2025 or SU-8 2050 or SU-8 2100, the Gerstel GM 1060, GM 1070 or GM 2060 or the Kayaku Microchem XP KMPR 1025, XP KMPR 1050 or XP KMPR-1100 negative tone photopolymer solution could be used. Again, to thicker negative tone photopolymer layers should be associated a longer than 90 seconds pre-exposure bake but still not exceeding 95° C. and for about as to drive-off more of its residual solvents in preparation for the exposure to ultra-violet light through a properly designed mask.
FIG. 9D shows that this second layer of a preferably 10 um thick MicroChem SU-8 2005 negative tone photopolymer is exposed using the highly collimated broadband UV source (g-line, h-line and l-line) of the EV Group Hercules processor through the openings of the mask defining the array of sidewalls of the array of microchannels. Being of negative tone, the photopolymer will reticulate in the regions exposed to the ultraviolet light and will locally become resistant to the chemical attack of the developer to be used later in the process. Following ultraviolet light exposure for an optimized dose of about 180 mJ/cm 2 , this first layer of a thick negative tone photopolymer is subjected to a 3 minutes duration post-exposure bake again not exceeding 95° C. as to drive-off more of the residual solvents and the chemical by-products formed by the ultra-violet light exposure. Again, if this MicroChem SU-8 2005 or SU-8 2010, this Gerstel GM 1040 or this Kayaku Microchem XP KMPR 1005 or XP KMPR 1010 negative tone photopolymer is replaced by a higher viscosity solution such as the Microchem SU-8 2025 or SU-8 2050 or SU-8 2100, the Gerstel GM 1060, GM 1070 or GM 2060 or the Kayaku Microchem XP KMPR 1025, XP KMPR 1050 or XP KMPR-1100 negative tone photopolymer solution, then the optimized dose would be higher than about 180 mJ/cm 2 , as to prevent under-exposure of this second layer of a negative tone photopolymer. To thicker negative tone photopolymer layers should also be associated a longer than 90 seconds post-exposure bake but still not exceeding 95° C.
FIG. 9E shows that this second layer of a preferably 10 um thick MicroChem SU-8 2005 negative tone photopolymer is developed using one of the two develop stations of the EV Group Hercules processor to define the defining the array of sidewalls of the array of microchannels. The regions of the photopolymer that have being exposed to the ultraviolet light passing through the openings of one or both of the masks remain intact because resistant to the chemical attack of the developer. These two layers of negative tone photopolymers are capable of achieving complex structures and mechanical features having a height:width aspect ratio as high as 10:1. Following suitable development of the photopolymer, the resulting photopolymer patterns are subjected to a post-develop bake at about 95° C. as to drive-off more of the residual solvents and the chemical by-products formed by the ultra-violet light exposure and by the develop. A vacuum bake at a temperature of about 180° C. is performed for about 2 hours to stabilize this exposed second 10 um thick layer. At this point, the developed and baked photopolymer patterns of the Device Wafer are ready to be aligned and to receive the transferred top photopolymer layer of the Carrier Wafer.
FIG. 10A shows that the Carrier Wafer supporting the developed and baked photopolymer patterns defining the array of covers of the array of microchannels is flipped-over and properly aligned to the Device Wafer integrating the array of sidewalls and the array of bottoms of the array of microchannels using the SmartView aligner of the EV Group Gemini processor. The alignment is precise within about 1 um. The aligned wafers, not yet in physical contact, are kept in position using a special fixture in preparation for loading of the pair of wafers into one of the four Universal bond chamber of the EV Group Gemini processor.
FIG. 10B shows that the pair of properly aligned wafers are loaded into one of the four Universal bond chamber of the EV Group Gemini processor. This Universal bond chamber allows the Carrier Wafer and the Device Wafer to become in physical contact by slowly pressing one against the other (without losing alignment accuracy) with a uniform force of 5 kN to 20 kN while heating the two wafers at a temperature of about 120-150° C. for about 20 minutes as to provoke the permanent bonding of the photopolymer of the CARRIER wafer to the exposed top bond material of the Device Wafer. Again, the precise alignment of about 1 um achieved with the SmartView is such that the thousands of protection capsules of the CARRIER wafer do not make a direct contact to the thousands of free-to-move mechanical devices of the Device Wafer during this bonding process. The bonded pair of wafers is unloaded from the Universal bond chamber, cooled-down to room temperature using a cool station and returned in a properly designed receiving cassette.
FIG. 10C shows that the two wafers are separated from each other. This is possible due to the hydrophobic nature of the SAM coating. This wafer separation can be performed using an EVG-850 DB wafer debonder.
FIG. 10D shows that the Device Wafer now incorporating the microchannel is heated under vacuum at more than 200° C. as to chemically stabilize the photopolymer and to achieve a solid permanent microchannel.
All references are herein incorporated by reference. | A MEMS device is manufactured by first forming a self-aligned monolayer (SAM) on a carrier wafer. Next, a first polymer layer is formed on the self-aligned monolayer. The first polymer layer is patterned form a microchannel cover, which is then bonded to a patterned second polymer layer on a device wafer to form microchannels. The carrier wafer is then released from the first polymer layer. | 6 |
FIELD OF THE INVENTION
[0001] The present invention relates to radio communication technologies, and in particular, to a technology for allocating downlink power.
BACKGROUND OF THE INVENTION
[0002] In communication systems, in order to raise the data transmission rate, a carrier aggregation (CA) technology was introduced. In original communication systems, each cell had only one waveband, while in current communication systems, multiple wavebands have been added, such as the following six wavebands: 450-470 MHz, 698-862 MHz, 790-862 MHz, 2.3-2.4 GHz, 3.4-4.2 GHz and 4.4-4.99 GHz. After the CA technology was introduced, a user equipment (UE) may use more than one waveband.
[0003] In addition to the introduced CA, in the communication systems, a Coordinated Multi-Point transmitting (CoMP) concept is also introduced. Under the current CoMP, because a non-CA case is relatively simple, a technical solution for allocating downlink power in the non-CA case has already existed. However, for a CA case, the CoMP becomes very complex, and the downlink power allocation also becomes complex. Therefore, the problem of power allocation based on the CA for multiple Evolved NodeBs (eNBs) has not been solved.
[0004] Therefore, in the current communication systems, no solution for allocating power exists in a case where the CA is introduced.
SUMMARY OF THE INVENTION
[0005] Embodiments of the present invention disclose a method and system for allocating downlink power, which can solve the problem of downlink power allocation.
[0006] The embodiments of the present invention adopt the following technical solutions:
[0007] An embodiment of the present invention provides a method for allocating downlink power. The method includes:
[0008] receiving measurement parameters which are of a reference signal and are reported by a UE and parameters which are of each aggregate waveband and are sent by a secondary eNB;
[0009] according to the received parameters, sending a transmit power of the secondary eNB on a waveband used by the UE to the secondary eNB; and
[0010] sending to the UE a first ratio of an energy of Orthogonal Frequency Division Multiplex (OFDM) technical symbols excluding the reference signal on each resource block on each downlink shared channel to an energy allocated to each resource block on the reference signal, and a second ratio of an energy of OFDM symbols including the reference signal on each resource block on each downlink shared channel to an energy of OFDM symbols excluding the reference signal on each resource block on each downlink shared channel.
[0011] An embodiment of the present invention provides another method for allocating downlink power. The method includes:
[0012] sending a parameter of each aggregate waveband to a donor eNB;
[0013] receiving a transmit power which is of a secondary eNB on a waveband used by the UE and is delivered, according to the parameter of the each aggregate waveband, by the donor eNB; and
[0014] sending downlink data to the UE according to the received transmit power.
[0015] An embodiment of the present invention provides a donor eNB, including:
[0016] a receiving unit, configured to receive measurement parameters which are of a reference signal and are reported by a UE and parameters which are of each aggregate waveband and are sent by a secondary eNB;
[0017] a first sending unit, configured to send, according to the received parameters, a transmit power of the secondary eNB on a waveband used by the UE to the secondary eNB; and
[0018] a second sending unit, configured to send to the UE a first ratio of an energy of OFDM symbols excluding the reference signal on each resource block on each downlink shared channel to an energy allocated to each resource block on the reference signal, and a second ratio of an energy of OFDM symbols including the reference signal on each resource block on each downlink shared channel to an energy of OFDM symbols excluding the reference signal on each resource block on each downlink shared channel.
[0019] An embodiment of the present invention also provides a secondary eNB, including:
[0020] a first sending unit, configured to send parameters of each aggregate waveband to a donor eNB;
[0021] a receiving unit, configured to receive a transmit power which is of the secondary eNB on a waveband used by the UE and is delivered by the donor eNB; and
[0022] a second sending unit, configured to send downlink data to the UE according to the received transmit power.
[0023] An embodiment of the present invention also provides a system for allocating downlink power, where the system includes the foregoing donor eNB and the secondary eNB. The system includes:
[0024] a donor eNB, configured to receive measurement parameters which are of a reference signal and are reported by a UE and parameters which are of each aggregate waveband and are sent by a secondary eNB; according to the received parameters, send a transmit power of the secondary eNB on a waveband used by the UE to the secondary eNB; and send to the UE a first ratio of an energy of OFDM symbols excluding the reference signal on each resource block on each downlink shared channel to an energy allocated to each resource block on the reference signal, and a second ratio of an energy of OFDM symbols including the reference signal on each resource block on each downlink shared channel to an energy of OFDM symbols excluding the reference signal on each resource block on each downlink shared channel; and
[0025] at least one secondary eNB, configured to send parameters of each aggregate waveband to the donor eNB; receive the transmit power which is of the secondary eNB on the waveband used by the UE and is delivered by the donor eNB; and according to the received transmit power, send downlink data to the UE.
[0026] In the method, apparatus and system for allocating downlink power according to the embodiments of the present invention, the UE sends measurement parameters of the reference signal to the donor eNB, and the secondary eNB sends parameters of each aggregate waveband to the donor eNB, so that the donor eNB sends, according to these parameters, the transmit power of the secondary eNB on the waveband used by the UE to the secondary eNB, and thus the secondary eNB can deliver data to the UE according to the transmit power; and the donor eNB also sends to the UE the information about the energy of OFDM symbols on each resource block on each downlink shared channel and the information about the energy allocated to each resource block on the reference signal, so that the UE can demodulate the received downlink data according to the information, and thus the downlink power allocation is completed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] To make the technical solutions of the embodiments of the present invention or the prior art clearer, accompanying drawings used in the description of the embodiments or the prior art are briefly described in the following. Evidently, the accompanying drawings illustrate only some exemplary embodiments of the present invention and those of ordinary skill in the art may obtain other drawings based on these drawings without creative efforts.
[0028] FIG. 1 is a flowchart of a method for allocating downlink power according to an embodiment of the present invention;
[0029] FIG. 2 is a flowchart of a method for allocating downlink power according to an embodiment of the present invention;
[0030] FIG. 3 is a flowchart of a method for allocating downlink power according to an embodiment of the present invention;
[0031] FIG. 4 is a schematic diagram of a system for allocating downlink power according to an embodiment of the present invention;
[0032] FIG. 5 is a comparative schematic diagram of normalized channel capacity based on two different algorithms;
[0033] FIG. 6 is a schematic diagram of a donor eNB according to an embodiment of the present invention;
[0034] FIG. 7 is a schematic diagram of a first sending unit according to an embodiment of the present invention;
[0035] FIG. 8 is a schematic diagram of a secondary eNB according to an embodiment of the present invention; and
[0036] FIG. 9 is a schematic diagram of a system for allocating downlink power according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0037] A method, an apparatus and a system for allocating downlink power according to the embodiments of the present invention are hereinafter described in detail with reference to the accompanying drawings.
[0038] It should be noted that the described embodiments are only some exemplary embodiments of the present invention, rather than all embodiments of the present invention. All other embodiments that those of ordinary skill in the art obtain without creative efforts based on the embodiments of the present invention also fall within the protection scope of the present invention.
[0039] As shown in FIG. 1 , an embodiment of the present invention provides a method for allocating downlink power. The method includes:
[0040] S 101 : Receive measurement parameters which are of a reference signal and are reported by a UE and parameters which are of each aggregate waveband and are sent by a secondary eNB.
[0041] S 102 : According to the received parameters, send a transmit power of each secondary eNB on a waveband used by the UE to the secondary eNB.
[0042] S 103 : Send to the UE a first ratio of an energy of OFDM symbols excluding the reference signal on each resource block on each downlink shared channel to an energy allocated to each resource block on the reference signal, and a second ratio of an energy of OFDM symbols including the reference signal on each resource block on each downlink shared channel to an energy of OFDM symbols excluding the reference signal on each resource block on each downlink shared channel.
[0043] As shown in FIG. 2 , an embodiment of the present invention also provides another method for allocating downlink power. The method includes:
[0044] S 201 : Send parameters of each aggregate waveband to a donor eNB.
[0045] The parameters of each aggregate waveband sent to the donor eNB include: the number of physical resources within a measured bandwidth corresponding to each aggregate waveband, and an energy allocated to each resource block on the reference signal corresponding to the aggregate wavebands.
[0046] S 202 : Receive a transmit power which is of the secondary eNB on a waveband used by the UE and is delivered by the donor eNB.
[0047] S 203 : Send downlink data to the UE according to the received transmit power.
[0048] In the method for allocating downlink power according to the embodiment of the present invention, the UE reports measurement parameters of the reference signal to the donor eNB, and each secondary eNB sends parameters of each aggregate waveband to the donor eNB, so that the donor eNB sends, according to these parameters, the transmit power of the secondary eNB on the waveband used by the UE to the secondary eNB, and thus the secondary eNB can deliver data to the UE according to the transmit power; and the donor eNB also sends to the UE the information about the energy of OFDM symbols including or excluding the reference signal on each resource block on each downlink shared channel and the information about the energy allocated to each resource block on the reference signal, so that the UE can demodulate the received downlink data according to the information, and thus the downlink power allocation is completed.
[0049] The implementation of the solution of the present invention is hereinafter described through a more specific embodiment.
[0050] Specifically, as shown in FIG. 3 , the embodiment may include the following steps:
[0051] S 301 : A donor eNB receives parameters reported by a UE.
[0052] As shown in FIG. 4 , this embodiment assumes that under a CoMP environment, there are three eNBs: eNB 1 , eNB 2 and eNB 3 , where eNB 1 is a donor eNB, while eNB 2 and eNB 3 are secondary eNBs. The UE uses three aggregate wavebands B 1 , B 2 and B 3 , and three carriers f 1 , f 2 and f 3 .
[0053] Thus, in this embodiment, the UE reports various measurement parameters to eNB 1 . These parameters include:
[0054] a reference signal received quality RSRQ i corresponding to each aggregate waveband, a reference signal received power RSRP i corresponding to each aggregate waveband and a reference signal transmit power P piloti corresponding to each aggregate waveband.
[0055] S 302 : Receive an X2 interface message sent by each secondary eNB, where the interface message includes: the number n i of physical resources within a measured bandwidth corresponding to each aggregate waveband, and the energy E rs allocated to each resource block on the reference signal corresponding to each aggregate waveband.
[0056] The X2 interface message may be an X2 Setup Request or an X2 Setup Response. Each secondary eNBi obtains, according to the definition of the measured bandwidth, the number n i of physical resources within the measured bandwidth corresponding to each aggregate waveband.
[0057] S 303 : According to the reported parameters, based on the channel gain, or also based on the interference received by the UE on the waveband used by the UE, calculate a transmit power of each secondary eNB on the waveband used by the UE.
[0058] First, it is required to calculate the interference N i received by the UE on the waveband i used by the UE. The calculation formula is as follows:
[0000]
N
i
=
n
i
·
RSRP
i
RSRQ
i
(
1
)
[0059] i is a positive integer. In this embodiment, because there are three eNBs, three aggregate wavebands are used, so the calculation formula is specifically as follows:
[0000]
N
1
=
n
1
·
RSRP
1
RSRQ
1
;
N
2
=
n
2
·
RSRP
2
RSRQ
2
;
N
3
=
n
3
·
RSRP
3
RSRQ
3
[0060] Then, the channel gain g ii of the secondary eNBi to the waveband i used by the UE,
[0000] g ii =10 (RSRP i −P piloti ) (2)
[0061] Where, the channel gain g 11 of the secondary eNB 1 to the waveband 1 used by the UE is:
[0000] g 11 =10 (RSRP 1 −P pilot1 ) ;
[0062] The channel gain g 22 of the secondary eNB 2 to the waveband 2 used by the UE is:
[0000] g 22 =10 (RSRP 2 −P pilot2 ) ;
[0063] The channel gain g 33 of the secondary eNB 3 to the waveband 3 used by the UE is:
[0000] g 33 =10 (RSRP 3 −P pilot3 )
[0064] In the following analysis, assume that the Maximal Ratio Combining method is acceptable to a terminal.
[0065] I. Based on the channel gain and the interference received by the UE on the waveband used by the UE, the transmit power of each secondary eNB on the waveband used by the UE is calculated as follows:
[0066] The formula for calculating the transmit power p ii of eNBi on the waveband i used by the UE is:
[0000]
{
p
11
+
p
22
+
…
p
ii
=
p
p
11
:
p
22
:
…
:
p
ii
=
(
g
11
/
N
1
)
:
(
g
22
/
N
2
)
:
…
(
g
ii
/
N
i
)
i
is
a
positive
integer
.
(
3
)
[0067] Where, p is a total power delivered to the UE under a CoMP environment;
[0068] p ii is a transmit power of eNBi on the waveband i used by the UE.
[0069] This embodiment is:
[0000]
{
p
11
+
p
22
+
p
33
=
p
p
11
:
p
22
:
p
33
=
(
g
11
/
N
1
)
:
(
g
22
/
N
2
)
:
(
g
33
/
N
3
)
[0070] The following result may be obtained:
[0000]
{
p
11
=
g
11
g
11
+
g
22
+
g
33
p
p
22
=
g
22
g
11
+
g
22
+
g
33
p
p
33
=
g
33
g
11
+
g
22
+
g
33
p
[0071] So the normalized channel capacity based on the channel gain and the interference received by the UE on the waveband used by the UE is:
[0000]
R
(
1
)
=
log
{
[
1
+
p
11
g
11
N
1
]
·
[
1
+
p
22
g
22
N
2
]
·
[
1
+
p
33
g
33
N
3
]
}
(
4
)
[0072] If there are more than three eNBs, the normalized channel capacity based on the channel gain and the interference received by the UE on the waveband used by the UE is:
[0000]
R
(
1
)
=
log
{
[
1
+
p
11
g
11
N
1
]
·
[
1
+
p
22
g
22
N
2
]
…
[
1
+
p
ii
g
ii
N
i
]
}
[0073] II. Based on the channel gain, the transmit power of each secondary eNB on the waveband used by the UE is calculated as follows:
[0074] The formula for calculating the transmit power p ii of eNBi on the waveband i used by the UE is:
[0000]
{
p
11
+
p
22
+
…
p
ii
=
p
p
11
:
p
22
:
…
:
p
ii
=
(
g
11
)
:
(
g
22
)
:
…
(
g
ii
)
i
is
a
positive
integer
.
{
p
11
+
p
22
+
p
33
=
p
p
11
:
p
22
:
p
33
=
(
g
11
)
:
(
g
22
)
:
(
g
33
)
(
5
)
[0075] The following result may be obtained:
[0000]
{
p
11
=
N
2
N
3
g
11
N
2
N
3
g
11
+
N
1
N
3
g
22
+
N
1
N
2
g
33
p
p
22
=
N
1
N
3
g
22
N
2
N
3
g
11
+
N
1
N
3
g
22
+
N
1
N
2
g
33
p
p
33
=
N
1
N
3
g
33
N
2
N
3
g
11
+
N
1
N
3
g
22
+
N
1
N
2
g
33
p
[0076] So the normalized channel capacity based on the channel gain is:
[0000]
R
(
2
)
=
log
{
[
1
+
p
11
g
11
N
1
]
·
[
1
+
p
22
g
22
N
2
]
·
[
1
+
p
33
g
33
N
3
]
}
(
6
)
[0077] If there are more than three eNBs, the normalized channel capacity based on the channel gain is:
[0000]
R
(
2
)
=
log
{
[
1
+
p
11
g
11
N
1
]
·
[
1
+
p
22
g
22
N
2
]
…
[
1
+
p
ii
g
ii
N
i
]
}
[0078] S 304 : Compare R( 1 ) and R( 2 ).
[0079] If R( 1 )>R( 2 ), the procedure proceeds to step S 305 a , and if R( 1 )<R( 2 ), the procedure proceeds to step S 305 b.
[0080] S 305 a : The donor eNB sends, through an X2 interface message, to each secondary eNBi the transmit power P ii that is calculated based on the channel gain and the interference received by the UE on the waveband used by the UE.
[0081] That is, for example, eNB 1 may send, through an eNB Configuration Update message, to eNB 2 the P 22 calculated based on the channel gain and the interference N i received by the UE on the waveband used by the UE, and to eNB 3 the P 33 calculated based on the channel gain and the interference N i received by the UE on the waveband used by the UE. If there are multiple secondary eNBs, a corresponding P ii is sent to different eNBi respectively.
[0082] S 305 b : The donor eNB sends, through an X2 Setup Request, the transmit power P ii that is calculated based on the channel gain to each secondary eNBi.
[0083] If R( 1 )>R( 2 ), it indicates that a larger channel capacity can be obtained based on the channel gain and the interference N i received by the UE on the waveband used by the UE, so each secondary eNB should adopt each secondary eNB' transmit power calculated by using this algorithm; and if R( 2 )>R( 1 ), it indicates that a larger channel capacity can be obtained based on the channel gain, so each secondary eNB should adopt each secondary eNB's transmit power of calculated by using this algorithm.
[0084] S 306 : The donor eNB sends, through a PDSCH-Configuration message, P A and P B , which correspond to the reference signal corresponding to each aggregate waveband, to each secondary eNBi.
[0085] Specifically, eNB 1 may send to the corresponding UE an RRC Connection Reconfiguration message carrying the P A and P B that are from eNB 1 , eNB 2 and eNB 3 .
[0086] Where
[0000]
P
A
=
E
A
E
rs
,
[0000] and E A represents the energy of OFDM symbols excluding the reference signal on each resource block on each downlink shared channel;
[0000]
P
B
=
E
B
E
A
,
[0000] and E B represents the energy of OFDM symbols including the reference signal on each resource block on each downlink shared channel.
[0087] After P A and P B are sent to the UE, the UE can demodulate a received downlink signal according to P A and
[0088] S 307 : Each secondary eNBi sends corresponding downlink data to the UE according to the received transmit power P ii .
[0089] That is, each secondary eNBi delivers data to the UE according to the received transmit power P ii sent by eNB 1 and carried in the PDSCH-Configuration message, for example, the transmit power of eNB 1 is P 11 , the transmit power of eNB 2 is P 22 , and the transmit power of eNBi is P ii .
[0090] S 308 : After receiving the downlink data, the UE demodulates the received data according to P A and P B .
[0091] In the method for allocating downlink power according to this embodiment, normalized channel capacities R( 2 ) and R( 1 ) are obtained respectively under two cases, that is, based on the channel gain, or also based on the interference received by the UE on the waveband used by the UE; each secondary eNB' transmit power calculated by the algorithm which results in a larger normalized channel capacity is notified to each secondary eNB through an X2 interface message, so that each secondary eNB send downlink data to the UE according to the calculated transmit power, and thus the power allocation under a CoMP environment can be completed and the downlink data throughput is raised; and P A and P B are sent to the UE, so that the UE can demodulate the received data according to P A and P B and thus can obtain downlink data information.
[0092] In a method for allocating downlink power according to another embodiment of the present invention, the transmit power p ii of eNBi on the waveband i used by the UE may be calculated based solely on the channel gain, that is, may be calculated by the foregoing formula (3):
[0000]
{
p
11
+
p
22
+
…
p
ii
=
p
p
11
:
p
22
:
…
:
p
ii
=
(
g
11
/
N
1
)
:
(
g
22
/
N
2
)
:
…
(
g
ii
/
N
i
)
i
is
a
positive
integer
.
(
3
)
[0093] and the calculated P ii is sent to the corresponding eNBi, and the eNBi sends downlink data to the UE according to the received P ii . Accordingly, P ii may be sent to eNBi in the manner described in the foregoing embodiment, and meanwhile, the foregoing P A and P B also need to be sent to the UE, thus a downlink power allocation is completed. This method can be adopted because in the majority of cases, the normalized channel capacity obtained based on the channel gain is larger than the normalized channel capacity obtained based on the channel gain and the interference received by the UE on the waveband used by the UE.
[0094] FIG. 5 is a schematic diagram of performance improvement in terms of normalized channel capacity based on the channel gain relative to normalized channel capacity based on the channel gain and the interference received by the UE on the waveband used by the UE under a specific scenario. Where, the horizontal axis is β, that is, a ratio of the channel gain to the sum of interference and noise, and the vertical axis represents a normalized channel capacity gain based on the channel gain relative to a normalized channel capacity gain based on the channel gain and the interference received by the UE on the waveband used by the UE, that is,
[0000]
R
(
1
)
-
R
(
2
)
R
(
2
)
×
100
%
.
[0000] G 1 , G 2 and G 3 are channel gains. As can be seen, relative to the calculation result based on the channel gain, the normalized channel capacity calculated based on the channel gain and the interference received by the UE on the waveband used by the UE is obviously larger.
[0095] In the majority of cases, a result similar to that in FIG. 5 can be obtained, so the calculation based on the channel gain and the interference received by the UE on the waveband used by the UE is a preferred algorithm. Thus, a power allocation method in which the P ii calculated based on the channel gain and the interference received by the UE on the waveband used by the UE is directly sent to eNBi may be adopted.
[0096] As shown in FIG. 6 , an embodiment of the present invention provides a donor eNB, including:
[0097] a receiving unit 61 , configured to receive measurement parameters which are of a reference signal and are reported by a UE and parameters which are of each aggregate waveband and are sent by a secondary eNB;
[0098] a first sending unit 62 , configured to send, according to the received parameters, a transmit power of the secondary eNB on a waveband used by the UE to the secondary eNB; and
a second sending unit 63 , configured to send to the UE a first ratio of an energy of OFDM symbols excluding the reference signal on each resource block on each downlink shared channel to an energy allocated to each resource block on the reference signal, and a second ratio of an energy of OFDM symbols including the reference signal on each resource block on each downlink shared channel to an energy of OFDM symbols excluding the reference signal on each resource block on each downlink shared channel.
[0100] On the basis of the foregoing scheme, as shown in FIG. 7 , the first sending unit 62 may further include:
[0101] a first processing module 621 , configured to calculate, based on the channel gain and the interference received by the UE on the waveband used by the UE, a first transmit power of each secondary eNB on the waveband used by the UE;
[0102] a second processing module 622 , configured to calculate, based on the channel gain, a second transmit power of each secondary eNB on the waveband used by the UE;
[0103] a judging module 623 , configured to judge, according to the first transmit power and the second transmit power obtained respectively by the first processing module 621 and the second processing module 622 , whether the normalized channel capacity calculated based on the channel gain and the interference received by the UE on the waveband used by the UE is larger than the noinialized channel capacity calculated based on the channel gain or not; and when the normalized channel capacity calculated based on the channel gain and the interference received by the UE on the waveband used by the UE is larger than the normalized channel capacity calculated based on the channel gain, instruct the sending module 624 to send the first transmit power, and otherwise, instruct the sending module 624 to send the second transmit power; and
[0104] a sending module 624 , configured to send the first transmit power or the second transmit power to the secondary eNBs.
[0105] As shown in FIG. 8 , an embodiment of the present invention also provides a secondary eNB, including:
[0106] a first sending unit 801 , configured to send parameters of each aggregate waveband to a donor eNB;
[0107] a receiving unit 802 , configured to receive a transmit power which is of the each secondary eNB on a waveband used by the UE and is delivered by the donor eNB; and
[0108] a second sending unit 803 , configured to send downlink data to the UE according to the received transmit power.
[0109] The parameters which are of each aggregate waveband and sent by the first sending unit 801 include: the number of physical resources within a measured bandwidth corresponding to the each aggregate waveband and an energy allocated to each resource block on the reference signal corresponding to the aggregate wavebands.
[0110] An embodiment of the present invention also provides a system for allocating downlink power, where the system includes the foregoing donor eNB and the secondary eNB. As shown in FIG. 9 , a donor eNB 901 and a secondary eNB 902 cooperate to form a system for allocating downlink power, which can realize a downlink power allocation.
[0111] In the system, the donor eNB 901 is configured to receive measurement parameters which are of a reference signal and are reported by a UE and parameters which are of each aggregate waveband and are sent by the secondary eNB 902 ; then send, according to the parameters reported by the UE and the secondary eNB 902 , a transmit power of the secondary eNB 902 on a waveband used by the UE to each secondary eNB 902 ; and send to the UE a first ratio of an energy of OFDM symbols excluding the reference signal on each resource block on each downlink shared channel to an energy allocated to each resource block on the reference signal, and a second ratio of an energy of OFDM symbols including the reference signal on each resource block on each downlink shared channel to an energy of OFDM symbols excluding the reference signal on each resource block on each downlink shared channel. Where, the donor eNB 901 may be implemented with reference to the scheme of FIG. 6 or FIG. 7 .
[0112] The secondary eNB 902 is configured to send parameters of each aggregate waveband to the donor eNB 901 ; then to receive the transmit power which is of each secondary eNB on the waveband used by the UE and is delivered by the donor eNB 901 ; and finally send downlink data to the UE according to the received transmit power. Where, the secondary eNB 902 may be implemented with reference to the scheme of FIG. 8 . There may be more than one secondary eNBs 902 .
[0113] According to the embodiments of the present invention, the donor eNB, the secondary eNB and the system that is formed by the donor eNB and the secondary eNB and is used for allocating downlink power may realize downlink power allocation with reference to the embodiments of the method for allocating downlink power, which is not repeatedly described herein.
[0114] In the donor eNB, the secondary eNB and the system for allocating downlink power according to the embodiment of the present invention, the UE reports measurement parameters of the reference signal to the donor eNB, and the secondary eNB sends parameters of each aggregate waveband to the donor eNB, so that the donor eNB sends, according to these parameters, the transmit power of the secondary eNB on the waveband used by the UE to the secondary eNB, and then the secondary eNB can deliver data to the UE according to the transmit power; and the donor eNB also sends to the UE the information about the energy of OFDM symbols including or excluding the reference signal on each resource block on each downlink shared channel and the information about the energy allocated to each resource block on the reference signal, so the UE can demodulate the received downlink data according to the information, and thus the downlink power allocation is completed.
[0115] Those of ordinary skill in the art may understand that all or part of processes in the methods of the foregoing embodiments may be implemented by a computer program instructing relevant hardware. The computer program may be stored in a computer readable storage medium, and when the computer program is executed, the processes in the methods of the foregoing embodiments may be included. The storage medium may be a magnetic disk, a Compact Disk-Read Only Memory (CD-ROM), a Read Only Memory (ROM), and a Random Access Memory (RAM).
[0116] Detailed above are only exemplary embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any modification or substitution readily derived by those skilled in the art within the technical scope of the disclosure of the present invention shall be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention is subject to the appended claims. | Embodiments of the present invention disclose a method, an apparatus and a system for allocating downlink power, which can solve the problem of downlink power allocation under a Coordinated Multi-Point transmitting (CoMP) environment and in a carrier aggregation (CA) technology. The method includes: calculating a power allocation according to measurement parameters which are of a reference signal and are reported by a terminal, and according to the number of physical resources within a measured bandwidth corresponding to each aggregate waveband, and an energy allocated to each resource block on the reference signal corresponding to the each aggregate waveband, where the number of physical resources and the energy are sent by a secondary evolved NodeB (eNB), sending the calculated power allocation to the secondary eNB, and sending to a user equipment (UE) energy information that corresponds to the reference signal corresponding to the each aggregate waveband of the secondary eNB. The present invention is applicable to downlink power allocation. | 7 |
BACKGROUND OF THE INVENTION
In laying concrete floors, ramps, pavement and like horizontal structures, it is customary in some instances to first provide a foundation or base slab, after which a top or finish layer is applied to the slab. Elongated boards or rods are mounted on the base slab to provide guide surfaces for the usual strike board or screed used in leveling or flattening the top surface of the finish layer. In order that the top surface be uniform over a fairly large area, it is important that the top surfaces of the guide boards or rods be disposed at a predetermined level from end to end thereof and relative to each other. This has heretofore been a problem, particularly when the top surface of a base slab is rough and uneven, requiring wedging of the guide boards or rods to bring the same, or at least portions thereof, to the required level.
SUMMARY OF THE INVENTION
The supporting stirrup of this invention enables a screed supporting guide member to be quickly and easily adjusted to a required level from end to end thereof and relative to the level of another guide member, as well as to be securely supported at the desired level. The supporting stirrup of this invention involves a base portion disposed to be embedded in a base slab, the base portion having a vertically extended threaded opening therein, a stud member screw threadedly received in the opening and extending upwardly from said base portion. A generally U-shaped stirrup element is mounted on the upper end of said stud for rotation on the axis of said stud, and means is provided for rotating the stud relative to said base portion, whereby to vertically move said stirrup element relative to said base portion.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a fragmentary view in top plan of a base or foundation slab of poured concrete, showing a pair of screed supporting members mounted on a plurality of the adjustable supports of this invention;
FIG. 2 is an enlarged fragmentary section taken on the line 2--2 of FIG. 1, and showing the top layer or slab of concrete disposed between the guide rods on the adjustable supports;
FIG. 3 is an exploded perspective view of the adjustable support of this invention; and
FIG. 4 is a view in perspective of a plug used to aid in mounting the adjustable support.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The adjustable support of this invention includes a base portion 11 that is commonly known as an expansion shield and which comprises an outer radially expansible sleeve 12 and an inner expander member 13 having a screw threaded axial opening 14 therethrough. An elongated stud 15 is screw threadedly received in the opening 14, and has a neck portion 16 at its upper end on which is journaled a generally U-shaped stirrup element 17. Just below the neck portion 16, the stud 15 is provided with a transverse opening 18 for reception of a pin or nail 19 by means of which the stud 15 may be rotated with respect to the expander 13. As shown, the stirrup 17 is adapted to receive and support the lower portion of an elongated screed guide 20 which may be of any suitable form but which, for the purpose of the present example, is shown as being in the nature of an elongated tube.
The above-described adjustable support is particularly adapted for use in the covering of a base slab of concrete or other suitable material with a top or finish slab. In the drawings, a base slab is indicated at 21, the top slab being shown in FIG. 2 and indicated at 22. When the base slab 21 is hardened or in a condition to support the top or finish slab 22, a hole is bored or otherwise produced in the base slab for each support. A pair of such holes is shown in FIG. 2 and indicated at 23. In the event that the base slab is made of poured concrete, the holes 23 may be produced with the use of plugs 24, one of which is shown in FIG. 4. These plugs may be inserted into the base slab while the same is in a fairly soft condition. As shown, each plug is formed with an enlarged diameter top flange 25 and a sharpened bottom end 26. The top flange 25 limits downward movement of the plug 24 into the base slab 21. When the base slab 21 is sufficiently hard to support the top slab 22, the plugs 24 are removed.
A base portion 11 of each adjustable support is inserted into each opening 23, and the outer sleeve 12 is expanded so that the base portion 11 is firmly held in its respective opening 23. Expansion of the sleeves 12 is achieved in the usual manner by a bolt, not shown, but screw threaded into the opening 14, and removed when the sleeve 12 is expanded sufficiently to firmly anchor the base portion 11 within its respective opening. A stirrup-equipped stud 15 is then screw threaded into each base portion 11 with the assistance of a pin or nail 19 and a screed guide rod or tube 20 is placed in two or more stirrups disposed in a row, as shown in FIG. 1. Each stirrup 17 is then adjusted to proper height by rotation of its stud 15, and the finish coat or slab 22 of concrete is poured into the area between the screed guides 20. The usual screed or striker bar, indicated at 27, is then used to produce a level top surface of the slab 22 between the screed guides 20, in the usual manner. After the top slab 22 has set sufficiently to be at least partially self-supporting, the screed guides 20 may be removed and the area filled in with cement.
The studs 15 and stirrups 17 may be made sufficiently inexpensive so as to permit the same to remain embedded in the top slab, if desired, otherwise, these may be removed from their base portions 11 and the area filled with cement.
While I have shown and described a commercial embodiment of my adjustable support for screed guides, it will be understood that the same is capable of modification without departure from the spirit and scope of the invention, as defined in the claims. | A stirrup for supporting elongated guide bars or rods for concrete screeds or strike bars used in leveling poured concrete floors, pavement and the like. The stirrup is vertically adjustably supported by a stud screw threaded in a base portion and extending upwardly from the base portion, the base portion being disposed to be embedded in a base slab. | 4 |
FIELD OF THE INVENTION
The present invention relates to electromechanical automatic transmissions and more particularly to an acceleration launch strategy for an electromechanical automatic transmission.
BACKGROUND OF THE INVENTION
Electromechanical dual clutch transmissions that include automated electromechanical shifting mechanisms and methods are known in the art. For example, U.S. Pat. Nos. 6,463,821, 6,044,719 and 6,012,561, disclose a dual clutch electromechanical automatic transmission.
The dual-clutch transmission does not include a torque converter. Therefore, launch and acceleration is created by closing one of the clutches. Under normal driving conditions, the clutch is not completely engaged. Rather, it is only closed far enough to transfer engine torque without transferring torque peaks. This so called “slip control” approach enables smooth shifting as well as fast disengagement of the clutch. However, issues arise when the vehicle is held stationary on an incline. While a motor vehicle can be held on an incline with a slipping clutch, after some period of time, typically based on incline slope, vehicle weight, and temperature, the slipping clutch will overheat. To prevent overheating, the clutch may be fully engaged or disengaged. If the clutch is disengaged, the vehicle would roll back unexpectedly. If the clutch is fully engaged, the vehicle would suddenly launch. There is a need for a launch acceleration strategy which avoids these issues.
SUMMARY OF THE INVENTION
Accordingly, a method for launching an automatic vehicle transmission utilizing dual clutches in place of a torque converter recognizes a vehicle transmission launch request, engages a first gear, monitors an activation condition of a vehicle brake, fully engaging a clutch associated with the first gear when the vehicle brake is released to enable the vehicle to accelerate to an idling speed, partially disengaging the clutch to a slip condition whenever the brake is activated and fully disengaging the clutch from the slip condition whenever clutch temperature exceeds a predetermined overheating threshold.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
FIG. 1 is a schematic illustration of a control system for a dual clutch electromechanical automatic transmission;
FIG. 2 is a flow chart illustrating the acceleration launch strategy for a dual clutch transmission according to the principles of the present invention; and
FIG. 3 is a graph illustrating the vehicle speed over time during the acceleration launch strategy of the present invention.
DETAILED DESCRIPTION
The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
The present invention pertains to a method for controlling a dual clutch automatic transmission. Although the present invention is applicable to virtually any dual clutch transmission, the method of the preferred embodiment is illustrated with the electromechanical automatic transmission disclosed in commonly assigned U.S. Pat. No. 6,012,561, which is hereby incorporated by reference in its entirety.
With reference to FIG. 1 , a powertrain controller 100 is provided for operating first and second clutch actuators 102 , 104 and first and second shift actuators 106 , 108 . The powertrain controller 100 provides signals to the respective driver motors 110 , 112 of the clutch actuators 102 , 104 as well as to the respective driver motors 114 , 116 of the shift actuators 106 , 108 . The powertrain controller 100 also monitors the position of the clutch actuators 102 , 104 as well as the shift actuators 106 , 108 via potentiometers 120 , 122 , 124 , 126 , respectively. Normal and uninterrupted power shifting between gears is accomplished by engaging the desired gear prior to a shift event. The transmission can be in two different gear ratios at once, preferably with only one clutch 102 , 104 being engaged for transmitting power during normal operation. In order to shift to a new gear ratio, the current driving clutch will be released during normal operation via the corresponding clutch actuator and the released clutch will be engaged via the corresponding clutch actuator. The two clutch actuators perform a quick and smooth shift as directed by the powertrain controller 100 which monitors the speed of the transmission input shafts 128 and 130 via speed sensors 132 and 134 , respectively, as well as the speed of the transmission output shaft 136 via a speed sensor 138 . Alternatively, the controller 100 determines the speed of the input shafts 128 and 130 based upon the known gear ratio and the speed of the driven shaft 136 as detected by sensor 138 . An engine speed sensor 140 is also provided and detects the speed of the flywheel 142 . Based upon the accelerator pedal position as detected by sensor 144 , the vehicle speed, and the current gear ratio, the powertrain controller 100 anticipates the next gear ratio of the next shift and drives the shift actuators 106 , 108 , accordingly, in order to engage the next gear ratio while the corresponding clutch actuator is in the disengaged position. As a gear is engaged, the corresponding input shaft which is disengaged from the engine output shaft becomes synchronized with the rotational speed of the transmission output shaft 136 . At this time, the clutch which is associated with the current driving input shaft is disengaged and the other clutch is engaged in order to drive the input shaft associated with the selected gear.
Referring to FIGS. 2 and 3 , the method of launching a dual clutch automatic transmission using the acceleration launch strategy 200 will now be described. With regard to the description in FIG. 2 , FIG. 3 graphically illustrates speed of the motor vehicle over time using the acceleration launch strategy 200 .
The method 200 begins at step 202 with the motor vehicle in a “launch state”. This “launch state” occurs when the motor vehicle is at rest (i.e., motor vehicle speed equals zero), corresponding to point “A” in FIG. 3 .
At the launch state, the controller 100 selects the first gear at step 204 . The controller 100 then determines if motor vehicle brakes are engaged at step 206 . If the brakes are engaged, there is no danger of the clutches overheating. If, however, the brakes are released, the controller 100 closes the first clutch at step 208 . As the clutch is closed, the motor vehicle will accelerate, indicated by the slope of the line indicated by reference “B” in FIG. 3 . If the first clutch is already hot, slip time is shorter, therefore there is less energy generated and the motor vehicle may accelerate faster, indicated by lines “D” in FIG. 3 .
The vehicle will accelerate to “idle” speed at step 210 , indicated by reference “C” in FIG. 19 . “Idle” speed is defined as the engine speed with no throttle when in first gear. By keeping the clutch fully engaged at step 208 , the clutch is prevented from overheating.
Idle speed continues until such time as the controller 100 determines that the brakes have been engaged, indicated at decision block 212 . The controller 100 then allows the clutch to slip at step 214 . As a result of the braking, the vehicle speed will decrease, shown by a line indicated by reference “E” in FIG. 19 .
If the clutch overheats during the slip event at decision block 216 , the controller 100 opens the clutch at step 218 . Since the brake is already engaged, there will be no unexpected rollback. The method 200 then repeats if another launch state is detected.
Area 302 of the graph of FIG. 3 indicates a high speed area that would occur if the transmission were equipped with a torque converter. Area 304 indicates roll-back speed that would occur with such a transmission system.
The invention has been described with reference to a preferred embodiment for the sake of example only. The scope of the invention is to be determined from an appropriate interpretation of the appended claims. | A method for launching an automatic vehicle transmission utilizing dual clutches in place of a torque converter avoids clutch overheating, sudden launch or roll-back by placing a clutch in a slip mode only after the vehicle's brakes have been actuated and fully disengaging the clutch upon over-heating detection. When launch is initiated, a first gear engaged and the brakes are released, the associated clutch is fully engaged to avoid overheating. | 5 |
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a key lock system for load binders to prevent the removal of the load binder after it has been tightened on the load.
SUMMARY OF THE INVENTION
The present invention includes an over dead center load binder having a rigid handle and chain engaging elements secured thereto. A keeper link forms a part of one of the chain engaging elements and a lock on the handle is adapted to engage therein to secure the handle to the link.
The primary object of the invention is to provide a lock for a load binder to prevent the removal of the binder after it has been tightened on a load.
Other objects and advantages will become apparent in the following specification when considered in light of the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation of the invention;
FIG. 2 is a front elevation of the invention;
FIG. 3 is a side elevation of the invention with the lock disengaged from the keeper;
FIG. 4 is an enlarged fragmentary vertical sectional view taken along the line 4--4 of FIG. 2 looking in the direction of the arrows;
FIG. 5 is a fragmentary front elevational view;
FIG. 6 is an enlarged fragementary vertical sectional view taken along the line 6--6 of FIG. 4 looking in the direction of the arrows with the locking balls in unlocked position; and
FIG. 7 is a view similar to FIG. 4 illustrating a slightly modified form of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings in detail wherein like reference characters indicate like parts throughout the several figures the reference numeral 10 indicates generally a locking load binder constructed in accordance with the invention.
The locking load binder 10 includes an elongate rigid handle 11 having a bifurcated end 12. A yoke 13 is secured in the bifurcated end 12 by means of a pivot pin 14 with the pivot pin 14 being spaced laterally from the center line of the handle. A bifurcated yoke 15 engages about the bifurcated end 12 of the handle 11 and is secured thereto by a pair of pivots 16, 17. The pivots 16, 17 are axially aligned and are spaced between the pivot 14 and the centerline of the handle 11.
A swivel link 18 is pivotally secured to the yoke 13 and has a link 19 secured thereto. A chain hook 20 is secured to the link 19 to be attached to a load chain 21 as can be seen in FIGS. 1 and 2.
A keeper link 22 is pivotally connected at one end to the bifurcated yoke 15 and at the opposite end to a chain hook 23. The chain hook 23 is adapted to engage the load chain 21 as can be best seen in FIGS. 1 and 2.
A cylinder lock 24 is secured to the handle 11 and is adapted to be actuated by a key 25. The handle 11 has a hollow conical boss 26 integrally formed thereon with a flat tongue 27 extending from the lock 24 centrally positioned therein. A pair of locking balls 28 are engaged in openings 29 in the conical boss 26 adjacent the outer end thereof with the openings 29 being shaped to permit the balls 28 to project partially outwardly of the conical balls 26 as can be seen in FIG. 4.
The keeper link 29 has a pair of plates 30, 31 secured together by rivets 32 with a keeper disk 33 secured therebetween. The keeper disk 33 has a conical opening 34 extending axially thereof to permit the boss 26 to engage therethrough. The balls 28 are adapted to engage the keeper disk 33 to prevent the handle 11 from being withdrawn from the keeper link 22 when the cylinder lock 24 has been turned to place the bar 27 in locked position engaging the balls 28. The keeper disk 33 has a thickness somewhat less than that of the keeper link 22 so that the boss 26 projects from the opposite side of the link 22 only slightly.
In the use and operation of the invention the chain 21 is applied to the load in a conventional manner and the hooks 20, 23 are engaged to opposite ends of the chain 21 with the handle 11 swung to a position closely adjacent the hook 20. From this position the handle is swung downwardly and toward the hook 23 thus tightening the chain 21 on the load with the handle 11 swinging over dead center to maintain the handle 11 in a binding position until it is moved bodily back to a position closely adjacent the hook 20. As the handle 11 is swung to its position closely adjacent the hook 23 the conical boss 26 is engaged in the conical bore 34 to the position illustrated in FIG. 4. The key 25 is then turned turning the lock and the lock bar 27 so that it forces the balls 28 outwardly in the openings 29 so as to engage behind the keeper disk 33 to prevent the conical boss 26 from being withdrawn from the conical bore 34 until the key is turned to permit the balls 28 to move inwardly of the conical boss 26.
A slightly modified form of the invention is illustrated in FIG. 7 wherein the handle 11a has a lock 24a with a conical boss 26a integrally formed with the handle 11a and extending outwardly therefrom. The conical boss 26a is somewhat longer than the conical boss 26 and extends completely through the keeper link 22a. A keeper disk 33a is mounted in the keeper link 22a and has a conical bore 34a extending therethrough to receive the conical boss 26a. The keeper disk 33a has the same thickness as the keeper link 22a and the conical boss 26a extends completely through the keeper disk 33a and the keeper link 22a as is seen in FIG. 7. The use and operation of the modified form of the invention as illustrated in FIG. 7 is identical to that of the preferred form of the invention illustrated in FIGS. 1 through 6.
Having thus described the preferred embodiments of the invention it should be understood that numerous structural modifications and adaptations may be resorted to without departing from the spirit of the invention. | A locking load binder having a conical lock tongue mounted on the handle and a keeper link secured to the yoke on one side of the handle and adapted to cooperate with the lock tongue to secure the handle thereto. The lock tongue includes cam driven locking balls which cooperate with the keeper link. | 8 |
This invention relates to desulfurization of hydrocarbon distillates from a crude oil distillation unit and light cycle oils from fluid catalytic cracking. In one aspect, it relates to a method of predicting useful catalyst life for different operating conditions and feeds in a hydrodesulfurization process. In another aspect, it relates to using a new computer program for simulating reaction kinetics and catalyst deactivation in predicting catalyst life for a hydrodesulfurization process.
BACKGROUND OF THE INVENTION
The removal of sulfur from distillate fractions by a catalytic reaction with hydrogen to form hydrogen sulfide is widely applied in petroleum refining. In commercial processes, active catalysts are typically employed in fixed bed reactors with continuous mass transfer through the reactor for removal of sulfur from distillate fractions and light cycle oil fractions, with the desulfurized product used for blending highway diesel fuels having a limited sulfur content. For example, it is known to desulfurize distillates and light cycle oils containing from about 0.2 to about 1.2 weight percent sulfur to a level of about 0.05 weight percent sulfur in the presence of catalyst which comprise alumina, cobalt and molybdenum.
It is also known in the art that the activity of such catalysts, used in desulfurization, will decline to an ineffective level after a period of time which is highly dependent on process conditions and on the sulfur species present in the oil being treated. The decline in activity is believed to be due to the formation of carbon on the catalyst, such that a higher reaction temperature is required to maintain a desired degree of desulfurization as the catalyst activity declines. Since desulfurization catalyst life is dependent essentially on process conditions and to a large extent on the boiling point distribution of sulfur species present in the oil, both of which can change during a typical commercial run, a reliable prediction of catalyst life has been extremely difficult. Accordingly, it has been necessary to periodically regenerate or replace catalyst to insure acceptable catalyst activity, and suspend production during the regeneration or replacement operation, even though useful levels of activity remained on the catalyst being replaced or regenerated.
Accordingly, it is a primary object of this invention to accurately predict life of a catalyst in a distillate or LCO hydrodesulfurization operation with the prediction based on a computer simulation.
It is a more specific object of this invention to predict the temperature-time profile of a catalyst HDS reaction for various process and feed conditions.
It is another object of this invention to provide substantial savings in a petroleum refining process operation by providing guidance for refiners in avoiding premature regeneration or replacement of catalyst in a distillate HDS process.
Another objective of this invention is to provide guidance for refiners in evaluating future feedstocks for economical HDS processing.
Still another object of this invention is to predict process conditions for deep desulfurization operations of existing units.
A further object of this invention is to provide data for designing, sizing and costing new units for deep desulfurization.
BRIEF SUMMARY OF THE INVENTION
In accordance with this invention, a computer based chemical kinetic model for a distillate HDS reaction, and a deactivation model for the catalyst are used together to simulate the HDS reaction by predicting a temperature-time profile of the HDS reaction, and to further predict the distribution of sulfur compounds in the desulfurized product. The catalyst deactivation model specifies the decline of activity with time and the current reaction temperature required to maintain the initial catalyst activity. The useful life of the catalyst is considered to be the time required for the catalyst activity in the simulated HDS reaction to decline sufficiently from its initial value that a predefined maximum reaction temperature is reached while maintaining the desired level of sulfur in the desulfurized product.
In a preferred embodiment, a rating case simulation forces agreement a simulated temperature-time profile and actual current temperature-time profile for an HDS reaction. This rating case simulation can be employed in conjunction with a prediction case simulation which anticipates the remaining catalyst life for assumed future process conditions, catalyst characteristics and sulfur distribution in the feed oil to be treated in the simulation.
Other objects and advantages of the invention will be apparent from the foregoing brief description of the invention and the claims, as well as a detailed description of the drawings, which are briefly described as follows:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified refinery flow diagram illustrating a distillate fraction for desulfurization.
FIG. 2 illustrates a typical sulfur boiling point distribution used to develop sulfur removal kinetics.
FIG. 3 illustrates relative reactivities of different sulfur species.
FIG. 4A illustrates a fixed catalyst bed reactor model divided into ten zones.
FIG. 4B illustrates a catalyst deactivation model divided into ten zones corresponding to the ten zones of the reactor model of FIG. 4A.
FIG. 5 is a graph showing reaction rate of dibenzothiophene.
FIG. 6 is a graph showing activation energy for dibenzothiophene.
FIG. 7 is a simplified computer program flow diagram which illustrates the overall simulation according to this invention.
FIG. 8 is a more detailed and flow diagram of a rating case illustration step 40 FIG. 7.
FIG. 9 is a more detailed flow diagram of a prediction case illustrated in step 44 of FIG. 7.
FIG. 10 a flow diagram illustrating the model calculation for the rating and prediction simulations.
FIG. 11 is a temperature-time profile for a rating case simulation
FIG. 12 is a temperature-time profile for a combined rating and prediction case simulation.
FIG. 13 is a FORTRAN display screen for the simulation showing results of a prediction case.
FIG. 14 is a 3-dimensional drawing showing simulated catalyst activity along the reactor.
FIG. 15 is a 3-dimensional drawing showing simulated H 2 pressure along the reactor.
DETAILED DESCRIPTION OF THE INVENTION
Hydrodesulfurization reactions are typically carried out in a fixed bed reactor. The oil feed is mixed with hydrogen-rich gas either before or after it is preheated to the proper reactor inlet temperature. Most hydrotreating reactions are carried out below 427° C. to minimize cracking and the feed is usually heated to between 260° and 427° C. The oil feed combined with the hydrogen-rich gas enter the top of the fixed bed reactor. In the presence of the catalyst, the hydrogen reacts with the oil to produce hydrogen sulfide, along with desulfurized products and other hydrogenated products. The reactor effluent is cooled before entering a separator which removes the hydrogen-rich gas from the desulfurized oil. The desulfurized oil is stripped of any remaining hydrogen sulfide and light ends in a stripper. The hydrogen gas may be treated to remove hydrogen sulfide and recycled to the reactor.
The hydrodesulfurization feedstock contemplated in the present invention is a distillate fraction boiling in a range of about 138°-393° C. which, for example, may be obtained in a refinery facility such as shown diagramatically in FIG. 1. Referring now to FIG. 1, a crude petroleum charge is supplied via conduit 2 to a crude unit 4. As is well known in the art, crude units may be operated to produce a variety of cuts including kerosene, light and heavy gas oils, etc. In the simplified embodiment shown in FIG. 1, the distillate fractions from the crude unit include a kerosene/diesel stream, hereinafter referred to as distillate. At conduit 6, the distillate stream is passed to the hydrotreater 8 for which catalyst life predictions are provided according to the present invention. Desulfurized product is withdrawn via conduit 18. Other illustrated fractions from the crude unit include a single light cycle oil stream which is withdrawn in conduit 19 from a fluid catalytic cracking unit 12, and for which catalyst life predictions for light cycle oil desulfurization may also be provided according to this invention. Naptha and lighter may be taken overhead via conduit 14 and topped crude or so called resid may be taken via conduit 16 for further processing.
DEVELOPMENT OF KINETIC MODEL
It is generally known that any suitable organic sulfur compound contained in a hydrocarbon feedstock can be hydrodesulfurized. Suitable organic sulfur compounds include sulfides, disulfides, mercaptans, thiophenes, benzothiophenes, dibenzothiophenes and mixtures thereof.
In accordance with one aspect of this invention, there is provided a mathematical model describing chemical kinetics for hydrodesulfurization of a hydrocarbon stream. The kinetic model illustrated, which assumes presence of 26 reactively different sulfur species in the hydrocarbon feed, is based on mass and energy balances for removal of individual sulfur compounds from a liquid hydrocarbon feed in a fixed bed reactor and includes effects of catalyst aging, temperature, hydrogen pressure, hydrogen sulfide inhibition and feed rate.
A chromatographic analysis showing boiling point distribution of sulfur compounds contained in a typical hydrocarbon feed is illustrated in FIG. 2. The sulfur compounds illustrated in FIG. 2 include benzothiophenes in section A and dibenzothiophenes in section B. The series of gas chromatograph traces in FIG. 3 illustrates the relative reactivities of the benzothiophene and dibenzothiophene sulfur species illustrated in FIG. 2, and the resistance of different sulfur compounds to desulfurization can be seen in the variation of individual compound reaction rates. In FIG. 3, the hydrocarbon feed of curve M contains 0.8 wt % total sulfur, curve N, 0.5% total sulfur, curve P, 0.4% total sulfur, curve Q, 0.3% total sulfur, curve R, 0.13% total sulfur and curve S, 0.05% total sulfur. The sulfur compounds with low boiling point temperatures disappear appreciably faster than the compounds with higher boiling temperatures , such that after desulfurization to less than 0.3 wt % total sulfur, only dibenzothiophene and its alkyl derivates remain in the product. Based on these results, a kinetic rate constant for each identified compound, which can be analyzed over the duration of an experiment, can be obtained. As previously indicated, the HDS reaction takes place in a fixed bed reactor, width reactant charged to the top of the reactor such that the charge of gaseous hydrogen and the liquid distillate flow downwardly through the catalyst. The chemical reaction occurs in the gas or liquid phase and forms a liquid product.
For accuracy in modeling, the reactor is considered as being divided into ten homogenous zones, as illustrated in FIG. 4A. Referring now to FIGS. 4A and 4B, the reactor model 20 and the catalyst deactivation model 22 are each divided into ten corresponding zones. The required model inputs are received via line 21 and deactivation model inputs are passed via line 24 from the reactor model. The deactivation model returns a value for catalyst activity via line 26. Sulfur conversion is then calculated for the first homogenous reactor lump based on a known distribution of sulfur components in the feed. The sulfur distribution for the product calculated in the first zone is passed to the second zone via line 28 and is used as the sulfur distribution for the feed to the second zone. Similarly, the reaction product composition of each upper zone is supplied as the feed to the next lower zone. At each zone, the current temperature and distribution of sulfur compounds of the treated fluid is recalculated according to a set of equations based on component continuity and energy balances, which are of the form:
Cs.sub.ip =Cs.sub.if exp(-K.sub.i *a.sub.c /Fr) (1)
K.sub.i =k.sub.oi exp(E.sub.i /RT)=K.sub.oi exp(-E.sub.i /RT)(2)
where: i=index for sulfur compounds, 1 to 26 for this illustration.
Cs if is the concentration of the sulfur component in the reactor feed, moles/L.
Cs ip is the concentration of the sulfur components in the desulfurized product, moles/L.
a c is the active catalyst volume.
K i is the reaction rate constant of the sulfur component.
Fr is feed rate of oil pumped to the reactor, in cm 3 /hour.
Fr/a c is the effective LHSV, hr -1
k oi is called the frequency factor and is unique to each sulfur compound being removed, hr -1 .
E i is the activation energy unique to each sulfur compound being removed in the reaction.
R is the ideal gas law constant and
T is the absolute temperature of the reaction mixture.
The constants E i and k oi must be determined experimentally by conducting experiments at different temperatures as will be more fully explained hereinafter. The feed rate liquid hourly space velocity (LHSV) and the sulfur components must be specified.
Active Catalyst volume a c is preferably determined in accordance with a separate model as will be described more fully hereinafter. Physical properties for the sulfur components of interest are generally available in the open literature.
DEVELOPMENT OF CATALYST DEACTIVATION MODEL
The catalyst deactivation model is a semi-empirical model partially based on observed process conditions. Seven test runs were completed using distillates having properties as shown in Table I over a cobalt and molybdenum loaded KF-742 catalyst. The catalyst was sulfided according to standard Catalyst Laboratory (CL) procedure so as to pass several times the amount of H 2 S required to completely sulfide the catalyst at 204° C. The catalyst was then conditioned by advancing the temperature to 371° C. and continuously maintaining 371° C. for about 48 hours, while passing additional H 2 S over the catalyst. Using 3/4 inch (1.9 cm) catalyst laboratory testing units, an activity baseline was established for seven distillate samples at the following process conditions: temperature 316° C., 2 LHSV, 4482 kPa and 56.6 m 3 /160 L H 2 . The data for six test samples are summarized in Table II. Table II also shows the standard deviation of catalyst testing in the 3/4 inch (1.9 cm) CL testing units. The reproducibility of these test runs was enhanced by plugging the top, bottom and interior furnace zones to reduce thermal gradients caused by air drafts, mixing 1/20 inch (0.13 cm) with 20/40 mesh alundum diluent in five equal lots and packing each lot separately in the reactor without a physical separator, such as a screen, so as to reduce catalyst/diluent segregation and improve wetting efficiency.
TABLE I______________________________________Properties of a Feedstock used in Life Tests______________________________________Sulfur, wt. % 0.56API gravity 13.4Hydrogen, Wt. % 8.95Nitrogen, ppm 955Aromatics, vol % 97Naphthalenes, vol % 52Simulated distillation; % off(converted to D86)°C.IBP 22310 25320 25830 26250 27270 28880 29790 310FBP 336______________________________________
TABLE II______________________________________(Amended)Baseline Activity Results ActivityTest Average Standard Relative toSample Product % S Deviation Average, °C.______________________________________1 .130 0.0036 -1.12 .129 0.0012 -0.73 .129 0.0022 -0.84 .135 0.0040 -3.15 .123 0.0068 +1.96 .123 0.0028 +1.7______________________________________
After the baseline activity was established (Table II), the six test samples were subjected to various aging conditions for a length of time which appeared to bring about sufficient deactivation as outlined below.
______________________________________Aging ConditionsTest Temp Press. LHSVSample °C. kPa hr.sup.-1 Hours______________________________________1 371 4482 3 9352 371 6895 1 18313 415 4482 1 6124 371 2758 1 14695 398 4482 3 8796 371 4482 1 1804______________________________________
These conditions were maintained throughout the aging period so that the sulfur content of the product was increased as the catalyst deactivated with age. These tests are designed to separate the deactivation kinetics from the sulfur reaction kinetics, so that the results may be applied to other distillate streams regardless of their sulfur reaction kinetics. After the aging time, the catalyst were each returned to the initial baseline conditions. Because of catalyst deactivation with age, the product sulfur was higher than originally observed.
Assuming that second order kinetics best fit the observed loss of catalyst activity, the temperature and pressure dependence of the catalyst activity was fit to an equation of the form:
1n(k.sub.c)=A+B(1000/T)+C(P) (3)
where
k c is the reaction rate constant for catalyst deactivation, ##EQU1## T is reactor temperature, °K. and P is reactor hydrogen pressure, psig
The constants A, B and C can be experimentally determined based on a light cycle oil having properties as shown in Table I or on another distillate fraction having other properties. Generally, the constants A, B and C for distillate fractions will include a range of values as follows:
A range 25 to 34
B range -21 to -29
C range -0.0005 to -0.0045
For the computer simulation, the catalyst activity is specified in terms of relative volumes of catalyst. For example, 50 cm 3 is considered twice as active as 25 cm 3 . Using the rate constant k c defined in equation (3) , an "active catalyst volume" is given in the following equation:
a.sub.3 =1/(k.sub.c * time+1/original catalyst volume) (4)
where the time and original catalyst volume are specified.
SULFUR REACTION RATE CONSTANTS DETERMINATION
The equations (1) and (2) that express the product sulfur distribution in terms of rate of reaction, catalyst activity and the sulfur distribution of the feed are called the kinetic model of the reaction. The pre-exponential factor k oi in equation (2) has the same units as a first order rate constant (hr -1 ) and is herein called a frequency factor. It is a function of absolute temperature expressed by the Arrhenius equation, where the activation energy and the frequency factor required in the Arrhenius equation must initially be determined experimentally.
EXAMPLES
This example describes determination of rate parameters for a sulfur compound and is relevant to the kinetics of hydrodesulfurization of a distillate stream.
A sample of light cycle oil having a sulfur distribution essentially the same as that shown in the chromatogram of FIG. 2 was hydrotreated at temperatures of 260°, 288° and 316° C. and at liquid hourly space velocities of 1, 2 and 4 cm 3 of feed per cm 3 of catalyst per hour using a 3/4 inch (1.9 cm) diameter catalyst laboratory test unit. The sulfur distribution of the feed and product was obtained using a series of gas chromatograms such as shown in FIG. 3. These chromatograms were analyzed by integrating the areas under the different peaks. It is noted, however, that not every peak in the chromatogram corresponds to one sulfur component only. In most cases, one peak is composed of several sulfur compounds which could have different individual reactivities.
In this example, the first peak occurring in the "B" group of peaks illustrated in FIG. 2 corresponds to dibenzothiophene. For determination of a rate constant as a function of temperature the natural log (1n) of the peak area for dibenzothiophene in the feed, divided by the peak area in the hydrotreated product is plotted versus 1/liquid hourly space velocity for experimental temperatures of 260°, 288° and 316° C. The slope of the line through the origin and the data points corresponding to a reaction temperature is taken to be the rate constant (K i ) for that temperature.
For the plots illustrated in FIG. 5, Curve A was obtained at a temperature of 260° C., curve B at 288° C. and curve C at 316° C. and the resulting rate constants are given in Table III below:
TABLE III______________________________________First Order Rate Constants for Removal of DibenzothiopheneTemp. (°C.) Rate (hr.sup.-1)______________________________________260 .45288 1.4316 5.8______________________________________
Next an Arrhenius plot for determining the activation energy of dibenzothiophene was drawn as shown in FIG. 6. The slope of the line formed by plotting the natural log of each rate constant versus the inverse of the absolute temperature is the activation energy for the removal of dibenzothiophene. The intercept of this plot is the natural log of the frequency factor (k oi ). For the slope of the straight line illustrated in FIG. 6, the activation energy is 28.6 KCal/mole, and the intercept, in 1n (k oi ), is 25.96.
COMPUTER SIMULATION
For simulating a chemical reaction on a suitable digital computer, it is only necessary to program the computer with a routine that describes what is happening in the reactor and to provide the computer with necessary data. A number of digital computer programs have been developed which facilitate data handling and graphic display capacity. One such program, which is well known, is called LOTUS 1-2-3. This program runs on many different computer systems and it is preferably used in this invention for input/output operations and as a graphic interface, with FORTRAN language used for numerical calculations. LOTUS 1-2-3 has capacity to execute many commands and is particularly effective in handling data base files and electronic spreadsheet functions where calculations involve a table of numbers arranged in rows and columns. Accordingly, the computer software utilized in the present invention alternates between LOTUS and FORTRAN to optimize execution time.
Referring now to FIG. 7, the simulation program is made operational at a start step 30 in response to an operator-entered command. The simulation routine first determines in a discrimination step 32 if a known sulfur distribution for the feed to be simulated is available. If available, the known distribution of sulfur compounds is entered into the simulation as Indicated in step 34. If a known distribution is unavailable, default values which may include concentrations of twenty-six of the most commonly encountered sulfur contaminants found in distillate fractions is entered as indicated in step 36. The simulation then proceeds to discrimination step 38 where a determination is made as to whether or not current plant operating data is available for use in the simulation. If current data is available, a rating case simulation is executed in step 40 to fit the simulated temperature-time profile to the current data. A graphic report showing a reaction temperature profile which compares recent actual temperatures and corresponding simulated temperatures, as shown in FIG. 11, is generated in step 42.
The simulation program then proceeds to step 44 and executes the prediction case based on projected operational data. The prediction case determines catalyst life based on the simulated reaction temperature reaching a pre-defined maximum temperature. A graphic report showing a temperature-time profile and a calculated life prediction at the end of run (EOR) as shown in FIG. 12, and a prediction case report display as shown in FIG. 13, are generated in step 46. Three dimensional displays showing, for example, percent catalyst activity and hydrogen partial pressure along the reactor, as shown in FIGS. 14 and 15, respectively, are generated in step 48.
Referring now to FIG. 8, a rating case simulation executed in step 40 of FIG. 7 is illustrated in somewhat greater detail. In step 50, input of data is via a LOTUS 1-2-3 spreadsheet. For example, an input spreadsheet might go from columns A through N and from row 1 through as many rows as required to accomodate the time span to be simulated. This input would include actual plant operating data as well as projected operating data. The contents of the columns A through M for a typical simulation are:
______________________________________COLUMN CONTENT______________________________________A Date beginning with the Start of Run (SOR)B Number of days since SOR.C Sulfur Content in feed.D Sulfur Content in Product.E Liquid Hourly Space VelocityF Reactor Inlet TemperatureG Reactor PressureH Reactor Pressure DropI Hydrogen Partial PressureJ Hydrogen FlowK Hydrogen PurityL Hydrogen ConsumptionM Reactor Delta TemperatureN Reactor Maximum Temperature______________________________________
In step 52, an ASCII file, which can be accessed by the simulation, is created by a LOTUS spreadsheet macro instruction, and model calculations are executed in step 54. The simulation then proceeds to step 56 where the simulated sulfur content in the product and the catalyst activity used in the simulation are adjusted to fit the simulated temperature-time profile to the actual profile.
Referring now to FIG. 9, a prediction case simulation executed in step 44 of FIG. 7 is illustrated in somewhat greater detail. In step 60, input data used in the prediction case is received via the output of the rating case, if any, plus input for projected data from a spreadsheet in a manner similar to the input from the spreadsheet illustrated in steps 50 and 52 in FIG. 8. In step 64, model calculations are executed.
Referring now to FIG. 10, the model calculations executed in steps 54 and 64 in FIGS. 8 and 9, respectively, are illustrated in somewhat greater detail. In step 70, K i values are calculated using equation (2) and the effective LHSV is calculated using the current active catalyst volume, i.e., (Fr/a c ). The program then proceeds to initialize data files as illustrated in step 72. Next, the simulation proceeds to step 74 to perform a series of calculations for each of ten model zones. Starting with the zone representing the top of the reactor and moving down the reactor, calculations for an assumed initial inlet temperature include: a product sulfur distribution according to equations (1) activity according to equation (3), and active catalyst volume according to equation (4). Recalculations are then made for K i values and effective LHSV until convergence for temperature is reached. Next, a determination is made as to whether or not the most recently calculated inlet temperature is greater than T max in step 76. If not, the calculations in step 74 are repeated until the maximum temperature is reached and the time involved is the catalyst life.
As previously stated, the maximum reaction temperature T max , which is illustrated in FIGS. 11 and 12, is predefined by the user and is entered with the spreadsheet data to produce an indication on the visual display as illustrted in FIGS. 11 and 12. This maximum reaction temperature can be altered as desired by the user to predict catalyst life for various temperatures.
In accordance with the statede objective to provide data for designing, sizing, and costing new units for deep desulfurization, the data base can be altered and the prediction mode simulation used to forecast the effect of changing various reaction conditions, and accordingly provide reliable design data for constructing new units.
While the invention has been described in terms of the presently preferred embodiment, reasonable variations and modifications such as simulating the removal of various combinations of sulfur species is possible by those skilled in the art and such variations and modifications are within the scope of the described invention and the appended claims. | Catalyst life in desulfurization of distillate hydrocarbon streams is predicted with the aid of a computer simulation which embodies an analytical kinetic model of a hydrodesulfurization reaction and a semi-empirical model for catalyst deactivation. The simulation specifies the decline of catalyst activity with time and a current reaction temperature required to maintain the initial catalyst activity. The useful life of the catalyst is considered to be the time required for catalyst activity in the simulated reaction to decline sufficiently from its initial level so that a predefined maximum reaction temperature is reached while maintaining a desired level of sulfur in the desulfurized product. The computer time needed to simulate the reaction is decreased by combining superior features of LOTUS 1-2-3 and FORTRAN language, such that input/output and graphic operations are implemented with LOTUS 1-2-3 and numerical calculations are executed in FORTRAN. | 2 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application is a non-provisional of, and claims the benefit of, co-pending, commonly-assigned U.S. Provisional Patent Application No. 60/561,089, entitled “AUDIT RECORDS FOR DIGITALLY SIGNED DOCUMENTS” (attorney docket no. 020967-003100), filed on Apr. 9, 2004, the entire disclosure of which is herein incorporated by reference for all purposes.
BACKGROUND OF THE INVENTION
[0002] The present invention relates generally to digitally-signed documents. More specifically, the present invention relates to systems and methods for creating, storing, archiving, and viewing audit information that pertains to the verification and validation of a digitally-signed document.
[0003] The process of securing network communication using public key encryption is well known. Public key encryption helps to ensure that data transmitted using networks remains in tact (i.e., unmodified in transit) and private between the sender and receiver (i.e., reduces eavesdropping). Further, public key encryption also allows a recipient to confirm a sender's identity. These functions are enabled in part through the use of a private key that is retained in secret by a first entity and a public key that the first entity freely distributes to others that wish to securely correspond with it. Public and private keys alone, however, do not fully solve the problem of identity verification as fraudulent public keys can be presented to a sender allowing an attacker to intercept a message. Successful identify verification requires that public keys are distributed by a trusted entity or through a chain of such entities. Certificate authorities (CAs) have been established as clearing houses for the trusted distribution of public keys.
[0004] When a recipient receives a document that was encrypted using a public key, the recipient views the content of the document by decrypting it with the corresponding private key. Conversely, a sender might encrypt using the private key, allowing anyone with the public key to decrypt using the freely-available public key. While this does not keep the message secret, if the message decodes correctly, it is probative of the sender's possession of the private key. The possession of the private key can be used as a form of attribution of the message to the sender, in effect “signing” the message.
[0005] When a recipient receives a document that was signed using a digital signature, the recipient verifies the digital signature by decrypting it with the public key and comparing the result to a one-way hash of the document. If the results are identical, the recipient is confident that the document was not modified in transit and that the private key used to create the digital signature corresponds to the public key of the sender. Further, the recipient confirms the identity of the sender by validating the certificate or chain of certificates that distributed the public key to the recipient from a CA. Only then is the recipient confident that the sender is the entity that the recipient believes him to be. A similar process is used to reverse the process.
[0006] For any number of reasons, the keys and certificates used to verify a signature and validate a sender's identity on a given day may not provide the same assurances in the future. For example, a valid private key at one time might be invalid at another time after a private key is changed. Thus, it may become impossible to recreate the process in the future and a user may forget that a particular document among many was verified and validated. For this reason, it may be important to retain audit records that document the verification and validation process.
[0007] Many computer systems that employ cryptographic operations also audit signature verifications and certificate validations. For example, many vendors offer systems implementing the Identrus™ Public Key Infrastructure System. These products record events such as signature verification and certificate validation using, for example, Online Certificate Status Protocol (OCSP) and/or Simple Certificate Validation Protocol (SCVP).
BRIEF SUMMARY OF THE INVENTION
[0008] Embodiments of the invention thus provide a computer-readable medium having stored thereon computer-executable instructions for implementing a method of verifying a digitally-signed document. The instructions include stored instruction for verifying a digital signature related to the document, stored instruction for validating at least one certificate associated with the signature, and stored instruction for storing audit information into a data structure movable as a unit. The audit information relates to verifying the digital signature and validating the at least one certificate, thereby retaining evidence that the document was verified. The instructions further include stored instruction for thereafter displaying the audit information.
[0009] In some embodiments, the stored instruction for storing audit information includes stored instruction for storing the audit information on a client computing device. The stored instruction for storing audit information may include stored instruction for storing the audit information on a server computing device. The instructions may include stored instruction for archiving the audit information to an archive server. The stored instruction for storing audit information may include stored instructions for storing the audit information in XML format. The stored instruction for storing audit information may include stored instruction for creating a combined verification report. The combined verification report may include a trusted timestamp that designates a date and time when verifying was performed, digital notarizations associated with at least one signature of the document, an encoded representation of a verified signature, a hash of the document, a transaction ID, a name of the document, document metadata, and/or the like. The encoded representation of a verified signature may include an encoded representation of a verified signature using Base-64 encoding. The hash of the document may include a hash of the document using Base-64 encoding. The stored instruction for storing audit information may include stored instruction for embedding the audit information in the document. The stored instruction for storing audit information may include stored instruction for storing the information in a common directory with the document. The stored instruction for storing audit information may include stored instruction for linking the information to the document using a unique identifier. The document may be in a variety of formats including Adobe Acrobat®, HTML file, XML file, ASCII text file, scanned digital image, or Microsoft® Word document. The digital signature may be in PKCS#7 format. The instructions may include stored instruction for digitally notarizing the audit information. The computer-executable instructions may include a standalone application, a software module, a plug-in, application feature, and/or the like.
[0010] In other embodiments, a method of verifying a digitally-signed document includes verifying a digital signature related to the document, validating at least one certificate associated with the signature, and storing audit information into a data structure movable as a unit. The audit information relates to verifying the digital signature and validating the at least one certificate, thereby retaining evidence that the document was verified. The method also includes thereafter displaying the audit information.
[0011] In some embodiments, storing audit information includes storing the audit information on a client computing device. Storing audit information may include storing the audit information on a server computing device. The method may include archiving the audit information to an archive server.
[0012] In still other embodiments, a user-viewable combined verification report relating to a digitally-signed document includes verification information relating to at least one digital signature of the document verification thereof and validation information relating to at least one digital certificate relating to the at least one digital signature. The combined verification report may include a trusted timestamp that indicates a verification date and verification time for the at least one digital signature. The combined verification report may include a trusted timestamp that indicates a validation date and time for the at least one digital certificate relating to the at least one digital signature. The combined verification report may include an encoded representation of a verified signature, a hash of the document, a transaction ID, a name of the document, document metadata, and/or the like. The encoded representation of a verified signature may include an encoded representation of a verified signature using Base-64 encoding. The hash of the document may include a hash of the document using Base-64 encoding. The combined verification report also may include, for a specific signer, the signer's name, the time a signer signed the document, an indication of an algorithm used to sign the document, a signer certificate, and/or the like. The combined verification report may include, for a specific certificate, an OCSP response relating to the validity of the certificate, an SCVP response relating to the validity of the certificate, a certificate status code, a certificate status message, a CRL used to validate the certificate, and/or the like.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] A further understanding of the nature and advantages of the present invention may be realized by reference to the remaining portions of the specification and the drawings wherein like reference numerals are used throughout the several drawings to refer to similar components. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.
[0014] FIG. 1 illustrates a client-side verification generator according to embodiments of the present invention.
[0015] FIG. 2 illustrates a server-side verification generator according to embodiments of the present invention.
[0016] FIG. 3 illustrates a combined verification report (CVR) according to embodiments of the invention.
[0017] FIG. 4 illustrates a verification and validation process according to embodiments of the invention.
[0018] FIG. 5 includes a screen shot of a user interface useful for viewing document verification results.
DETAILED DESCRIPTION OF THE INVENTION
[0019] It is desirable for encryption products to store signature verification and certificate validation results for a given document in a common data structure, possibly along with the document and digital signature. Such records would include a timestamp for each time the signatures are verified, the certificates are validated, and/or the document is accessed. It is also desirable for audit information to be stored locally so that a user would not have to access a server to view the information. It is also desirable to have a user interface that displays the audit information in an understandable format, even for complex documents having many signatures and certificates. Thus, systems and methods are needed that address these and other needs.
[0020] Embodiments of the present invention provide systems and methods for creating, storing, archiving, and viewing audit information relating to verification and validation of digitally-signed documents. Embodiments may also include combined verification reports that document the audit results. Embodiments may be implemented locally, for example on a user computer, or remotely, for example on a server computer. Here, “document,” when used as a noun, refers to text, code, a message, other sequence of bits, or the like, conveyed from a sender to a user.
[0021] Having described embodiments of the invention generally, attention is directed to FIG. 1 , which illustrates an exemplary “client-side” embodiment 100 of the invention. In this embodiment, the verification and validation process is accomplished by an application 102 residing on a user computing device 104 that us also used to provide documents to users. The application 102 may be any computer-executable instruction set for accomplishing the functions described herein. In some embodiments, the application comprises a software module, such as a plug-in, programmed to work with a primary application, such as a web browser or a word processor. In other embodiments, the application comprises a feature embedded into a primary application. In still other embodiments, the application comprises a standalone application. In some embodiments, the application works only on a limited number of file types. In still other embodiments, the application works on a wide variety of file types. Many other examples are possible. The user computing device 104 may comprise any of a number of well known devices, such as a laptop, a workstation, a PC, a desktop, a PDA, or the like.
[0022] Once an intended recipient receives an encrypted document from a sender 106 , usually by way of a network 107 , the application 102 verifies the signatures and validates the associated certificates. The application also produces a combined verification report (CVR) 108 that documents the process. The CVR 108 may include a number of entries as will be described in greater detail hereinafter with respect to FIG. 3 .
[0023] In this embodiment, the CVR 108 may be stored locally on the user computing device 104 in any of a number of well know data structures. For example, the CVR may comprise a record in a database, a text file, a formatted document file, a spreadsheet file, or the like. In a specific embodiment, the CVR is stored in XML format, one example of which is illustrated in Appendix A. In some embodiments, the CVR is stored as part of the document to which it pertains.
[0024] The CVR can be archived to an archive server 110 . In some embodiments, this comprises copying the CVR, usually via a network 112 , to the archive server using a secure transmission protocol such as SSL. The network 112 may be a part of the network 107 , such as the Internet, or may be, for example, an internal network, such as an intranet. At the archive server 110 , the CVR may be stored as a a record in a database, a text file, a formatted document file, a spreadsheet file, or the like. The CVR is stored in XML format in a specific embodiment.
[0025] Those skilled in the art will appreciate that client-side embodiment 100 is merely exemplary. Many other examples of client-side embodiments are possible and apparent to those skilled in the art in light of this disclosure.
[0026] Attention is directed to FIG. 2 , which illustrates an exemplary “server-side” embodiment 200 of the invention. As with the embodiment 100 of FIG. 1 , this embodiment is merely exemplary of a number of possible server-side embodiments. In the embodiment shown, a verification and validation application 202 resides on a server computer 203 through which a user computer 204 accesses external resources, such as a sender 206 via a network 207 . The user computer 204 may be any of the aforementioned computing devices. The server computer 203 may be any suitable computing device. As with the previous embodiment, the application 202 may be a standalone application, a module, an embedded feature, or the like.
[0027] The application 202 may be executed by a user using a client computer or may be configured to execute automatically upon receipt of a document from a sender. The application 202 creates a CVR 208 and stores it locally in one or more of the aforementioned formats. As with the previous embodiment, the CVR may be archived to an archive server 210 via a network 212 .
[0028] Having described two exemplary embodiments, attention is directed to FIG. 3 , which illustrates an embodiment of a CVR 300 according to the invention. A sample CVP in XML format is provided as Appendix A hereto. The CVR 300 shown includes information relating to the verification and validation of particular digitally-signed documents. In some embodiments, the CVR is updated each time the document to which it pertains is accessed, which may include merely opening the document, verifying and validating the digital signatures and associated certificates, and/or the like. In other embodiments, a new CVR is created each time a document is accessed.
[0029] As previously mentioned, the CVR may be stored at a client computer and/or a server computer. Further, the CVR may be loaded to an archive server. The CVR may be stored as a standalone file, a record in a database, an entry in a spreadsheet, and/or the like. The CVR may be stored in any of a number of well-known formats. In a specific embodiment, the CVR is stored in XML format. In other embodiments, the CVR may be an Acrobat® format file, a HTML file, an ASCII text file, a scanned digital image, a word processing document, or the like. In some embodiments, the CVR is stored as part of the document to which it relates. Many other examples are possible.
[0030] The CVR may include any or all of a number of entries. For example, the CVR may include a USERID that identifies the recipient of the document or someone who accesses the document, the user's name, the time the document was verified, the verification result, and the like. If the CVR is stored in a database along with CVRs for other documents, then each CVR may include an identifier of the document to which it pertains.
[0031] In some embodiments, the CVR includes the verification and validation status of the document. For each signature in the document, the CVR may include the signature that was verified, a trusted timestamp for the signature, and any digital notarizations associated with the signature. The CVR may include an encoded representation of the signature that was verified, which may use, for example, Base-64 encoding. The CVR may include a hash of the document that was verified, which also may use Base-64 encoding. In some embodiments, the CVR includes a transaction ID, a unique identifier that can be used to located the CVR at a later time, if, for example, the CVR is stored on an archive server while the transaction ID is stored in the document. The CVR also may include the name of the document that was verified and/or metadata about the document (e.g., the title of the document, author of the document, document summary, etc.).
[0032] Signatures may include multiple signers. The CVR may include, for each signer, the signer's information, the signing time, an indication of the algorithm used to sign, the message digest algorithm, the signer certificate, and the signer certificate chain. For each certificate in the chain for each signer, the CVR may include an OCSP or SCVP response relating to the validity of the certificate, including the certificate status code, the certificate status message, and binary and/or textual representation of the OCSP or SCVP response. The CVR also may include a binary and/or textual representation of the OCSP or SCVP request. In some embodiments, the CVR includes information identifying a certificate revocation list used to validate the certificate or any other information that proves that the certificate's validity was checked. Those skilled in the art can derive other embodiments upon review of this disclosure.
[0033] Attention is directed to FIG. 4 , which illustrates an embodiment of a method 400 of verifying digitally-signed documents according to the invention. Method 400 may be implemented in either of the aforementioned embodiment or other appropriate system. Those skilled in the art will appreciate that Method 400 is merely exemplary of a number of possible embodiments. Other embodiments may include more, fewer, or different steps than those described herein. Further, the steps described herein need not be traversed in the order shown here.
[0034] Method 400 begins at block 402 , when a digitally-signed document is received. In some embodiments, this event triggers subsequent verification of the document. In others, a user initiates the subsequent operations. The document may be in any of a variety of formats. For example, the document may be in Adobe Acrobat®, HTML, XML, ASCII, or other suitable format. The document may comprise, for example, a scanned digital image, a formatted text document, or the like. Examples of formatted text documents include Microsoft® Word documents including text and/or other document objects, such as images, boxes, data structures, and the like. Other examples include ANSI text, Unicode text, rich text format (RTF) documents, and the like.
[0035] At block 404 , one or more digital signatures on the document are verified. As is known, this may comprise decrypting the document, decrypting the signature, hashing the document, and/or comparing the hash to the decrypted signature. In a specific embodiment, the digital signature is in PKCS#7 [PUBLIC KEY CRYPTOGRAPHY STANDARDS No. 7: CRYPTOGRAPHIC MESSAGE SYNTAX STANDARD (RSA Laboratories, Version 1.5, Nov. 1, 1993)].
[0036] At block 406 , the digital certificates associated with each signature are validated. This may comprise validating each certificate in a certificate chain leading to a trusted root certificate. Validating certificates may comprise querying using OCSP (Online Certificate Status Protocol) or Simple Certificate Validation Protocol (SCVP) to obtain information relating to the validity of each certificate. In some embodiments, validating certificates comprises referencing a CRL (Certificate Revocation List). Other examples are possible and apparent to those skilled in the art.
[0037] At block 408 , a CVR is created. The CVR includes the information described previously with respect to FIG. 3 .
[0038] At block 410 , a portion or all of the CVR may be notarized and the results stored as part of the CVR. In some embodiments, the CVR or a hash of the CVR are sent to a third party notary service which signs the CVR or CVR hash. A new CVR is then created which contains the original CVR along with the new signature created by the notary service. The signature from the notary service may optionally include a timestamp representing the time of the notarization.
[0039] At block 412 , the CVR is stored. This may comprise storing the CVR on a user computer or a server computer. The CVR may be stored as a record in a database, an entry in a spreadsheet or other document, as a standalone file, or the like. The CVR may be stored as part of the document to which it relates. The CVR may be stored in any of a variety of formats, including, for example, XML.
[0040] At block 414 , the CVR is archived to an archive server. This may comprise securely transmitting the CVR to the archive server using SSL or other appropriate file transfer protocol.
[0041] At block 416 , the CVR is viewed by a user handling the verified document. The CVR may be viewed in any of a number of ways. A user may view the CVR on his computer monitor and/or may print the CVR. The user may access the CVR via a web browser, in some examples. Depending on the format of the CVR, the user may view it using an application, such as a word processor, spreadsheet program, or the like, or present it to another program for further processing. With respect to embodiments that store the CVR in XML format, an XML stylesheet may be used to render the CVR. Many other examples are apparent to those skilled in the art in light of this disclosure.
[0042] FIG. 5 includes a screen shot of a user interface 500 according to embodiments of the invention. Using the user interface 500 , a user may view information relating to the validation status of a signature and/or the validation status of any associated certificates. The user interface 500 may be displayed on a device such as the user computing device 104 of FIG. 1 .
[0043] The user interface 500 may include, for example, summary information 502 , such as whether a signature has been verified successfully and whether a certificate has been verified successfully. Additional details may be included relating to the certificate, such as the certificate issuer 504 and/or whether the certificate remains valid 506 . Other embodiments may include additional information.
[0044] Having described several embodiments, it will be recognized by those of skill in the art that various modifications, alternative constructions, and equivalents may be used without departing from the spirit of the invention. Additionally, a number of well known processes and elements have not been described in order to avoid unnecessarily obscuring the present invention. For example, those skilled in the art know how to arrange computing devices into a network and configure communication among them. Accordingly, the above description should not be taken as limiting the scope of the invention, which is defined in the following claims. | A computer-readable medium having stored thereon computer-executable instructions for implementing a method of verifying a digitally-signed document includes stored instruction for verifying a digital signature related to the document, stored instruction for validating at least one certificate associated with the signature, and stored instruction for storing audit information into a data structure movable as a unit. The audit information relates to verifying the digital signature and validating the at least one certificate, thereby retaining evidence that the document was verified. The instructions further include stored instruction for thereafter displaying the audit information. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of copending application Ser. No. 11/639,650 filed Dec. 15, 2006. The Ser. No. 11/639,650 application is incorporated by reference for all purposes.
BACKGROUND AND SUMMARY
Various embodiments relate to a roofing material and more particularly to a roofing underlayment including anti-slip properties.
In both residential and commercial roofing applications, a roof covering material is utilized to provide the main water protection barrier. Whether the primary roof covering material comprises composite shingles, metal panels or shingles, concrete or clay tiles, wood shakes, or slate, a primary roof covering material is used to protect the building interior from water ingress.
Roofing underlayment is sometimes described as Type I and Type II roofing underlayments as specified in Chapter 15 of the IBC (International Building Code), and defined in Chapter 9 of the IRC (International Residential Code); and is also specified as Type 15 and Type 30 underlayments in Chapter 15 of the UBC (Uniform Building Code).
In some circumstances, whether due to primary roofing material design, installation practices, or accidental breach of the primary roofing material, water can penetrate the primary roofing material. To protect the building interior in these circumstances, it is common to provide a secondary layer called a roofing underlayment, beneath the primary layer. The roofing underlayment acts as a water and moisture barrier.
A variety of roofing underlayment products is commonly used. The two major classes are mechanically attached and self-adhered underlayments. The latter are commonly referred to as “peel and stick”.
It is desirable that a roofing underlayment provide a surface which has a sufficiently high coefficient of friction (“COF”) to increase the safety for an applicator to walk upon. The coefficient of friction describes the ratio of the force of friction between two bodies and the force pressing them together. The coefficient of friction is an experimentally determined value. The phrase “high coefficient of friction” in this document means a sliding coefficient of friction of at least 0.5 when tested with dry leather and at least 0.7 when tested with dry rubber (per CAN/CGSB-75.1-M88).
Underlayments should be easily affixable to a roofing surface, for example by nailing or adhesion. They should ideally be impermeable to moisture. High tensile and tear strengths are also desirable to reduce tearing during application and exposure to high winds. Underlayments should be light in weight to facilitate ease of transport and application, and should be able to withstand prolonged exposure to sunlight, air and water.
A common mechanically attached roofing underlayment product used in the United States and Europe is bituminous asphalt-based felt, commonly referred to as “felt.” Typically, this felt comprises paper felt saturated with asphaltic resins to produce a continuous sheeting material which is processed into short rolls for application.
Such felts generally demonstrate good resistance to water ingress and good walkability in dry and wet roof conditions. Disadvantages include very low tensile and tear strengths, relatively high weight per unit surface area, a propensity to dry and crack over time, very low resistance to ultraviolet (“UV”) exposure, high likelihood of wind blow off, and a propensity to absorb water causing buckling and wrinkling, thus preventing the application of direct primary roofing materials such as composite shingles.
To overcome these shortcomings, several products have been marketed with high tensile and tear strengths. These materials are generally reinforced non-woven polymeric synthetic materials, rather than asphaltic felts. They are generally lightweight, thin, have higher tensile, tear and burst strengths as compared to felts, and are superior to felts in UV resistance and resistance to drying and cracking over time.
A major drawback of these polymer underlayments is their low COF on the walking surface in dry or wet conditions. This problem limits the commercial attractiveness of such products in high pitch roofs or in climates characterized by frequent and sporadic wet or humid conditions. Thus, a roofing underlayment made from a polymer material which also provides anti-skid properties would be ideal for use in a roofing membrane.
A roofing underlayment according to an embodiment comprises a reinforcing layer, which is extrusion coated on at least one side with an anti-slip coating layer. In an embodiment, the reinforcing layer comprises a woven polyethylene or polypropylene scrim. The anti-slip coating layer comprises a compound based on a styrene and ethylene/butylene-styrene, S-E/B-S, block copolymer, such as the compound sold under the trademark KRATON® MD6649. The anti-slip coating layer is low in cost and helps prevent water from penetrating the primary roofing material. In addition, the anti-slip coating layer provides an improved anti-skid surface upon which an individual may safely walk.
DETAILED DESCRIPTION
Various embodiments are directed toward a roofing underlayment which provides an improved anti-slip surface. The roofing underlayment comprises a reinforcing layer and one or more coating layers disposed on at least one surface of the reinforcing layer.
In one embodiment, the reinforcing layer is a woven fabric. In another embodiment, the fabric or scrim is made from polyolefin materials such as polyethylene, polypropylene, copolymers and other combinations thereof. In an exemplary embodiment, the scrim is made from polypropylene film material and comprises 11 tapes per inch of a 875 denier polypropylene tape in the warp direction and 5.8 tapes per inch of a 1250 denier polypropylene tape in the weft direction.
In an alternative embodiment, the reinforcing layer comprises a nonwoven fabric.
The scrim can be coated on one or both sides. At least one coating layer comprises an anti-slip coating layer. The anti-slip coating layer comprises a compound based on a styrene and ethylene/butylene, S-E/B-S, block copolymer. In one embodiment the anti-slip layer comprises a compound based on a styrene and ethylene/butylene, S-E/B-S block copolymer, comprising from about 30%-75% by weight styrene-ethylene/butylene-styrene block copolymer, from about 0%-50% by weight resin, and from about 0.1%-2% by weight antioxidant/stabilizer/dusting agent. One such suitable S-E/B-S based compound is KRATON® MD6649 compound manufactured by KRATON Polymers, referred to hereafter as “KRATON 6649”. The anti-slip coating layer may additionally comprise KRATON® G1730M compound, referred to hereafter as “KRATON 1730”. It has been found surprisingly, that the anti-slip coating layer provides anti-skid properties to the roofing underlayment and also maintains tack when water is applied to the surface of the underlayment.
The smooth coating allows water run-off to prevent water build-up under the feet of an individual walking on the surface of the underlayment.
In another embodiment, high melt flow, low modulus, thermoplastic olefin resins are also used for the coatings of various embodiments. Suitable polyolefins include, but are not limited to, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), and polypropylene (PP). Polyolefin coatings are selected to be compatible with the woven scrim to which they are applied. Suitable polyolefin resins include, but are not limited to, Adflex KS084P olefin resins manufactured by Basell Service Company B.V (“Basell”) and based on material produced from Basell's proprietary “Catalloy” process.
The coatings of the various embodiments are suitable for extrusion coating onto scrim. Extrusion coating of a layer of scrim may be accomplished by melting the coating in an extruder and extruding through a film die onto the scrim. The molten polymer and scrim are transported between a nip roll and a chill roll to cool the molten coatings. A chill roll temperature of 45° F. to 85° F. is commonly used.
The roofing underlayment of one embodiment comprises a scrim that is coated on both upper and lower surfaces. The upper surface coating has a thickness of approximately 0.5 mils to 4 mils. The lower surface coating has a thickness of approximately 0.5 to 4 mils. In an exemplary embodiment, the upper surface coating has a thickness of 1.5 mils and the lower surface coating has a thickness of 1.2 mils. In one embodiment the upper surface coating comprises two layers, a core layer and a skin layer. The core layer and skin layer are co-extruded onto the scrim. The skin layer comprises an S-E/B-S block copolymer such as Kraton MD6649, another polyolefin resin such as LDPE, or h-PP plus UV, a pigment (colour), and anti-block. The core layer comprises polyolefin resins such as LDPE and h-PP, plus UV, and a pigment (colour). The lower surface comprises only one layer of coating. The lower surface coating layer comprises polyolefin resins such as Adflex KS084P and LDPE, antiblock, UV, and pigment (colour). While the upper surface coating can be a single anti-slip coating layer, co-extrusion of the skin and core layers, as described, allows Kraton to be used only where necessary.
The coatings may comprise other additives including, for example, U.V. stabilizers (including Tinuvin® 328 and Chimassorb® 944, both are registered trademarks of, and supplied by Ciba-Geigy Corporation, NY, Ampacet Corporation UV100, based on Ciba Specialty Chemical's proprietary Shelfplus®), antiblock additives, colorants, and pigments, to the extent that such additives do not interfere with the anti-skid properties of the coatings.
When used, pigments and colorants may be added as part of a color masterbatch. The color masterbatch is formed by combining the pigments (colorant) with a polypropylene and/or polyethylene carrier compatible with the polyolefin coatings. In general, compatible carriers can be determined by creating extruded melt blends and testing for phase separation in the extrudate.
Table 1 provides the coefficient of friction values obtained after slip resistance testing in accordance with CAN/CGSB-75.1-M88 was conducted on the roofing underlayment of an embodiment. This test method is used to rate the performance of ceramic tiles but it has also been used to rate the slip performance of synthetic underlayments.
TABLE 1
Test Description
Test Result
Requirement
Pass/Fail
Leather Boot (dry)
Machine Direction
0.93
>0.50
Pass
Cross Direction
0.85
Leather Boot (wet)
Machine Direction
0.72
>0.60
Pass
Cross
0.76
Direction
Rubber Boot (dry)
Machine Direction
1.25
>0.70
Pass
Cross Direction
1.18
Rubber Boot (wet)
Machine Direction
1.56
>0.65
Pass
Cross Direction
1.53
Various embodiments are illustrated, but not limited, by the examples which follow.
It has also been determined that embossing a pattern on the anti-slip coating layer to impart an uneven surface thereto will give significant improved wet slip resistance by increasing the roughness of the surface of the anti-slip coating layer. There is also an improved physical grip of a shoe to the anti-slip coating layer. The embossed pattern will also break up any plane of water that may be formed between a shoe and the anti-slip coating layer, thus preventing or minimizing a significant reduction in grip of the anti-slip coating layer.
The anti-slip coating layer is embossed in a further additional processing step. One technique involves applying heat and pressure while running the roofing underlayment through a nip assembly, one roll of which has a positive of the pattern to be embossed on the anti-slip coating layer. Embossment may also be undertaken on a printing press just prior to printing the roofing underlayment. Embossment may also be carried out by extrusion coating onto a patterned chill roll or by direct embossment after cooling on a smooth chill roll.
The embossment pattern may be of any type as long as it increases the roughness of the anti-slip coating layer surface. For example and not as a limitation, in one embodiment an embossment pattern is a sand pattern or a diamond pattern. In another embodiment, the pattern is a small scale decorative pattern made up of interlocking diamond shapes.
EXAMPLES
Example 1
A roofing underlayment according to one embodiment comprises a woven polypropylene scrim. The scrim comprised upper and lower coating layers corresponding with upper and lower surfaces of the scrim. The polypropylene scrim used was a woven polypropylene with 11.0×5.8 tapes per inch. The upper surface of the scrim was coated first. The upper coating layer was comprised of a first upper layer, or core layer and a second upper layer, or skin layer. The core layer comprised 70% by weight of the upper coating layer. The skin layer comprised 30% by weight of the upper coating layer. The core layer comprised 2% UV100 (UV MasterBatch), 10% Beige 889822 (pigment), 4% AB150 (anti-block), 20% LDPE (low density polyethylene), and 64% h-PP (homo-polymer polypropylene). The skin layer comprised 2% UV100 (UV MasterBatch), 10% Beige 889822 (pigment), 8% AB1505 (anti-block), 15% LDPE (low density polyethylene), and 65% KRATON® MD6649 compound (S-E/B-S block copolymer). The melt temperature range of the upper coating layer was between 450° F. to 550° F. Minimum chill roll temperatures varied between 45° F. and 85° F.
The lower coating layer comprised 73.5% KS084P (thermoplastic olefin resin), 8.0% LDPE (low density polyethylene), 2% UV100 (UV MasterBatch), 10.5% White MB (70% TiO2 Pigment and 30% polyethylene), 6% AB 150 (anti-block). The melt temperature range of the lower coating layer was between 490° F. to 550° F. Chill roll temperatures varied between 45° F. and 85° F.
Example 2
A second roofing underlayment according to another embodiment comprises a woven polypropylene scrim. The scrim comprised upper and lower coating layers corresponding with upper and lower surfaces of the scrim. The polypropylene scrim used was a woven polypropylene with 11.0×5.8 tapes per inch. The upper surface of the scrim was coated first. Upper coating layer was comprised of a first upper layer, or core layer and a second upper layer, or skin layer. The core layer comprised 70% by weight of the upper coating layer. The skin layer comprised 30% by weight of the upper coating layer. The core layer comprised 1% UV100 (UV MasterBatch), 10% Beige 889822 (pigment), 8% LDPE (low density polyethylene), and 81% h-PP (homo-polymer polypropylene). The skin layer comprised 2% UV10 (UV MasterBatch), 10% Beige 889822 (pigment), 8% AB150 (anti-block), 10% h-PP (homo-polymer polypropylene), and 70% KRATON® MD6649 compound (S-E/B-S block copolymer). It should be noted that the amount of h-PP in the skin layer varies from about 5% to about 20% based on chill roll sticking, adhesion, and tack. The amount of KRATON®1 MD6649 compound can also be varied based on the amount of h-PP. Typically MD 6649 could range from 30% to 90%. The melt temperature range of the upper coating layer was between 450° F. to 550° F. Chill roll temperatures varied between 45° F. and 85° F.
Lower coating layer comprised 73.5% KS084P (thermoplastic olefin resin), 8.0% LDPE (low density polyethylene), 2% UV100 (UV MasterBatch), 10.5% White MB (70% TiO2 Pigment and 30% polyethylene), 6% AB 150 (anti-block). The trial was run using standard polypropylene conditions. The melt temperature range of the lower coating layer was between 490° F. to 550° F. Chill roll temperatures varied between 45° F. and 85° F.
Typical characteristics of the S-E/B-S block copolymer (KRATON®1 MD6649 compound) used in various embodiments are provided in Table 2.
TABLE 2
Specification
Property
Test Method
Range/Value
Antioxidant content
KM08
0.1-0.3%
mass
Melt Flow Rate (190° C./2.16
ISO 1133
13-19
g/10 min
kg)
Bulk Density
BAM 931
2-3
g/100 pellets
Hardness [a]
ASTM 2240
34-42
Shore A (30 s)
Specific gravity
ISO 2781
0.91
Mg/m 3
Participate matter index
BAM 903
A
Yellowness index
BAM 1015
<5
Typical characteristics of the thermoplastic olefin resin (Adflex KS084P) used in the various embodiments are provided Table 3.
TABLE 3
Specification
Property
Test Method
Range
Density
ASTM D 792
0.88
g/cm 3
Melt Flow Rate (230° C.)
ASTM D 1238
30
g/10 min
Tensile Strength @ Yield
ASTM D 638
6
MPa
Flexural Modulus
ASTM D 790
110
MPa
Tensile Elongation @ Yld
ASTM D 638
23%
Tensile Elongation @ Brk
ASTM D 638
670%
Notched izod impact (23° C.)
ASTM D 256
No Break
Durometer Hardness (Shore D)
ASTM D 2240
44
It will be understood by those skilled in the art that various embodiments may exist in other specific forms without departing from the scope of the invention disclosed and that the examples and embodiments described herein are in all respects illustrative and not restrictive. Those skilled in the art will recognize that other embodiments using the concepts described herein are also possible. Further, any reference to claim elements in the singular, for example, using the articles “a,” “an,” or “the” is not to be construed as limiting the element to the singular. Moreover, a reference to a specific time, time interval, and instantiation of scripts or code segments is in all respects illustrative and not limiting. | A roofing underlayment comprises a reinforcing layer, which is extrusion coated on at least one side with an anti-slip coating layer. The reinforcing layer comprises a woven polyethylene or polypropylene scrim. The anti-slip coating layer comprises a compound based on a styrene and ethylene/butylene-styrene, S-E/B-S, block copolymer, such as the compound sold under the trademark KRATON® MD6649. The anti-slip coating layer may also be embossed. The anti-slip coating layer is low in cost and helps prevent water from penetrating the primary roofing material. In addition, the anti-slip coating layer provides an improved anti-skid surface upon which an individual may safely walk. Embossment improves the wet slip resistance of the roofing underlayment. | 3 |
BACKGROUND
The present invention relates to self-contained breathing apparatus such as may be worn to sustain the respiration of its user in noxious or oxygen-depleted environments. Such apparatus conventionally includes a portable source of breathing gas (e.g. a compressed air cylinder) and breathing interface means (e.g. a full or partial facemask) through which the breathing gas is in use supplied from said source to the respiratory passages of the user at a regulated rate.
In the case of self-contained open-circuit compressed air breathing apparatus it is usual for the air cylinder(s) to be carried on the back of the user, being mounted for this purpose on a plate or frame attached to a body harness comprised of strong webbing which passes over the user's shoulders and around his waist. As an alternative to this form of harness, it is known to support the cylinder on the back of a jerkin-type garment. Breathing sets are also known where an air cylinder is slung by a strap across one shoulder to be worn at the hip, but this arrangement is only suitable for relatively small and light cylinders, consequently providing very short endurance. A back-carrying harness arrangement is generally preferred because the weight of the cylinder(s) is distributed symmetrically and at a position which impedes the movements of the user the least.
SUMMARY OF THE INVENTION
In one aspect, the present invention seeks to provide a self-contained breathing apparatus with means for its storage and transportation when not in use and which, by suitable conversion when the apparatus is to be donned for use, avoids the need for a separate supportive harness. The invention has been developed in particular for use with open-circuit compressed air breathing apparatus of the kind generally known as "inspection" or "escape" sets using a cylinder of typically 3 to 6 liters capacity which will provide a nominal endurance of, say, 15 to 30 minutes. However, the invention is by no means limited to such usage and in principle may be used in conjunction with any size or form of portable breathing gas source which is capable of being supported on the torso. In particular, in addition to open-circuit compressed air (or oxygen) breathing apparatus the invention may find application to the closed-circuit regenerative type of self-contained oxygen breathing apparatus.
Accordingly in one aspect the invention resides in self-contained breathing apparatus comprising a portable source of breathing gas and breathing interface means through which the breathing gas is in use supplied from said source to the respiratory passages of the user at a regulated rate, together with an assembly of flexible sheet material which can be folded and closed to form a case enclosing at least said gas source when not in use and which when opened and reversed is adapted to form a garment to be worn over the torso and to support the gas source for use, preferably on the back of the user.
In a preferred embodiment the case encloses a complete breathing circuit ready for use subject to opening the case, donning the garment and breathing interface means, and opening a valve to release breathing gas from the source thereof to the interface means. The garment which the flexible sheet material is adapted to form preferably is in the nature of a jerkin (vest) which is donned by passing the arms through respective holes and closing together two sides across the chest.
A preferred embodiment of the invention will now be more particularly described, by way of example, with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the case within which the remainder of the apparatus can be carried;
FIG. 2 is a plan view of the apparatus with the case opened and its side flaps unfolded;
FIG. 3 is a plan view of the apparatus following from the condition of FIG. 2, with two inner flaps unfolded;
FIG. 4 is a plan view of the apparatus turned over from the condition of FIG. 3;
FIG. 5 is a plan view of the apparatus following from the condition of FIG. 4, with the originally outer flaps folded inwards, and the garment now ready for donning;
FIG. 6 is a perspective view showing the garment during donning; and
FIGS. 7 and 8 are respective perspective views from the front and rear showing the breathing apparatus in use.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The following particular description indicates the sequence of operations which is performed to convert the illustrated breathing apparatus, which is of the open-circuit compressed air kind, from its stored mode into its operational mode.
Referring to FIG. 1, the illustrated case is formed from a single piece of synthetic fabric, such as the multilayer, flame resistant, plasticised PVC on polyester fabric known as CAFLEX FP600FR, (CAFLEX is a trade mark of Coating Applications (Textiles) Limited). In principle, however, any natural or synthetic fabric that will support the weight of the breathing apparatus and meet other relevant performance criteria may be used. This case has two folded-up side flaps 1 and 2 which are held together along the length of their upper (as viewed) edges by a zip fastener 3. More particularly, and as also indicated in FIG. 2 which shows the flaps 1 and 2 unfolded, the flap edges which are united in the FIG. 1 condition have respective generally straight lengths 4 at the rear (as viewed) of the case leading to second generally orthogonal straight lengths 5 at the top of the case and inclined lengths 6 at the front (as viewed) of the case. Loops of webbing 7 are sewn on to provide handles for hand-carrying the case. Alternatively, longer loops may be provided if it is preferred to carry the case over the shoulder.
FIG. 2 shows the apparatus after releasing the zip fastener 3 and unfolding the side flaps 1 and 2, their inner surfaces now being seen. It is assumed that the apparatus is laid out on a floor, table or other flat surface. Revealed inside the case are two inner flaps 8 and 9, folded one over the other and held together by respective perpendicular strips 10,11 of the synthetic fibre fastening material known as VELCRO, (VELCRO is a registered trade mark of Selectus Limited). The inner flaps 8 and 9 are made from respective pieces of the same material as forms the outer flaps 1 and 2 and are respectively attached to the outer piece at their top and lower-side edges, at the regions indicated by the stitched patches 12 and 13 in FIGS. 3 and 4. The regions between the patches 12 and 13 where the flaps 8 and 9 are not attached to the outer piece will form the arm holes 27 and 28 of FIG. 5 when the garment is ready for donning. Also seen in FIG. 2 is the top of the cylinder pouch 14 which is revealed in its entirety in FIG. 3.
FIG. 3 shows the apparatus after separating and folding back the inner flaps 8 and 9. A pouch 14 is sewn centrally to the outer piece of fabric, at a position which lies along the base of the case in FIG. 1. This pouch is open at its lower (as viewed) end to receive a compressed air cylinder which is hidden from view in FIG. 3 apart from its on/off valve fitting 15 and attached first-stage pressure reducer 16. Another pouch 17, closed by a central zip fastener 18, is sewn onto the now-revealed side of the inner flap 9, which houses a facemask fitted with a demand valve; (these items will be seen at 30 and 31 in FIG. 7). A low-pressure hose 19 leads up through the cylinder pouch 14 from the low-pressure side of the pressure reducer 16 and down through a fabric guide 20 to the facemask demand valve in pouch 17. A high-pressure hose 21 leads in parallel to the hose 19, but from the high-pressure side of the fitting 16, to a conventional cylinder contents (pressure) gauge and low-pressure warning whistle assembly 22. Also seen in FIG. 3 are the two parts of a waist clip fastener 23,24 which will be attached together when the apparatus is donned.
FIG. 4 shows the apparatus after turning it over bodily from its FIG. 3 condition. From this condition the two side flaps 1 and 2 of the case are folded in on themselves as shown in FIG. 5, with the respective carrying handles 7 trapped between. These flaps are held in the folded-in condition by respective pairs of VELCRO strips 25,26 seen in FIG. 4. With the flaps 1 and 2 folded in and their top edges tucked out through the arm holes 27,28 as shown in FIG. 5, the apparatus is ready for donning. The three fabric pieces 1/2, 8 and 9 collectively define a jerkin or vest, of which the back is provided by the folded piece 1/2, (which originally defined the case of FIG. 1), and the two sides are provided by respective "inner" flaps 8 and 9 (which are now, of course, on the outside). As previously indicated, the arm holes 27,28 seen in FIG. 5 are defined between the patches 12 and 13 where the respective flaps 8 and 9 are stitched to the flaps 1 and 2.
The jerkin is donned by the user passing his right and left arms respectively through the arm holes 27 and 28 so that the folded-in flaps 1,2 lie along his back on the inside of the garment, with the cylinder pouch 14 of course now being located on the outside. Flap 8 is folded across his chest from the right (as worn) and flap 9 is folded across the top of the flap 8 from the left. For ease of illustration FIG. 6 shows the jerkin donned and flap 9 partially folded over. The flaps 8 and 9 are held together across the chest by interengaging VELCRO strips 10 and 11, their perpendicular orientation permitting engagement over a wide range of different chest sizes. The fastening is completed by clipping together the two parts of the fastener 23,24 as shown in FIG. 7 adjusting if required by pulling through the length of webbing 29 by which the fastener part 23 is attached to the flap 1 (see also FIG. 3). The principal fastening of the flaps 8 and 9 around the body of the user is achieved by the VELCRO strips 10 and 11, however, the fastener 23,24 serving only as a safety device to prevent the accidental tearing open of the VELCRO connection.
With the jerkin thus donned, the facemask pouch 17 is now located on the chest of the user. The zip fastener 18 is released to permit removal and donning of the facemask 30 as shown in FIG. 7. It is shown in this Figure fitted with a positive-pressure demand valve 31 connected to the hose 19, an exhalation valve 32 and speech transmission diaphragm 33. The breathing circuit remains connected up while the apparatus is in its storage mode so all that is required to put it into operation is for the user to don the facemask and turn on the air supply from the cylinder by turning the handwheel of the valve 15 seen in FIG. 8. The air cylinder may be supported within the pouch 14 by any convenient means, such as by a ring around the neck of the (inverted) cylinder attached by dog clips to rings sewn into the open (lower) end of the pouch.
After use and any replacement or recharging of the air cylinder, the apparatus is returned to its storage mode within the bag of FIG. 1 by reversal of the procedure described above.
The guide 20 seen most clearly in FIG. 6-8 is formed from a loop of fabric and made large enough for the pressure reducer 16 and hoses 19,21 (or gauge/whistle 22 and hoses) to pass through it. The loop is then folded on itself and held together by VELCRO strips so that when in use the hoses are held firmly in position.
A particular advantage of the illustrated apparatus is that the whole breathing circuit is held in place by the design of the garment and no tools are required to remove it from the garment when cleaning or disinfection/decontamination is to be carried out. | A self contained breathing apparatus comprises a compressed air cylinder, facemask and hose which when not in use are stored and carried within a case formed from an assembly of flexible sheet material. The elements of the case are constructed such that when it is opened and reversed it is adapted to form a garment to be worn over the torso and support the air cylinder for use. | 8 |
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to paper production, and more particularly to a device for severing a moving web of paper with a tear strip, whereby the paper web is wound onto a drum and, upon severing with the tear strip, it is wound onto an empty drum. The tear strip is a tear strip made of paper.
Webs of paper, made in a paper mill system, are wound up onto cores. When the paper roll reaches a predetermined package diameter the paper web, which is moving at a speed of about 25 meters per second, must be severed. The following web can then be wound onto an empty coil. A tear strip is used for severing the web. The tear strip winds itself spirally on the empty core, and at the same time the web of paper is severed along a spiral line. To enable recycling of the tear strip together with the portions of the paper web that have been damaged in the severing operation, it is known to make the tear strip out of paper.
Such a tear strip, which must have high tensile strength and high rigidity, has been made heretofore from a number of paper strings located side by side and glued together. To accomplish the gluing operation, the paper strings are wetted with a water-soluble adhesive over their entire surface. Since they are then pressed together as they rest against one another, they stick to one another at the contacting surfaces. After the adhesive is dry, the thus-made tear strip is wound up onto a roll.
Prior art tear strips of this kind have a number of disadvantages:
When the strings are made they are wetted with adhesive over their entire circumference. The tear strip wound up onto a core can therefore stick under the influence of moisture. Also under the influence of moisture, the glued-together paper strings can come loose from one another, thus lessening the strength of the tear strip. Moreover, the separated individual strings may possibly cause problems when the tear strip is used.
Another disadvantage of the prior art tear strip is that the individual paper strings from which it is made must have a minimum diameter. The tear strip thus has a minimum thickness which, when the strip is used to sever paper webs and the weight of the paper is relatively low, can cause deleterious effects and the paper web is damaged. The need also exists for manufacturing such a tear strip with exact tolerances, to preclude attendant problems in its movement through a feed channel. This need can be met only with difficulty in the case of a tear strip made from a plurality of strings, however, since the strings cannot be made in exact sizes.
Moreover, when the tear strip is cut apart, the individual strings are severed at different points along the length of the tear strip, which can likewise cause functional problems. In addition, it is quite difficult to unravel tear strips made from twisted strings in the recycling process.
Finally, surface layers of adhesive, which are applied to the tear strips (for the purpose of securing the tear strip to the empty core and to enable initiating the paper web severing process at a later point), stick to a tear strip made of paper strings only along the jacket lines on the outside of the paper strings. This means that the layers of adhesive can come off the tear strip.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide a tear strip for severing a moving paper web, which overcomes the above-mentioned disadvantages of the heretofore-known devices and methods of this general type, and which overcomes the particular disadvantages associated with the tear strip made from individual strings.
With the foregoing and other objects in view there is provided, in accordance with the invention, a tear strip assembly for severing a moving paper web being wound onto a drum, for enabling the paper web to be wound onto an empty drum, comprising: a tear strip formed of a multiply folded paper strip, said paper strip defining a plurality of plies resting on one another, said plies being at least partially adhesively bonded to one another.
Several further embodiments of the general principle are disclosed and claimed. For instance, the paper strip has two lateral regions, and the lateral regions are folded over multiple times; or the two lateral regions are folded over onto one side; or the two lateral regions of the paper strip are folded over onto mutually different sides.
In accordance with an added feature of the invention, the paper strip has two side edges, and the two side edges of the paper strip are located approximately centrally in the tear strip; or the two lateral regions of the paper strip are folded over onto one side, overlapping one another; or the two side edges of the paper strip are located approximately at respective side edges of the tear strip.
In accordance with an additional feature of the invention, there is provided an inlay paper strip disposed between at least two of the plies, and the inlay paper strip is adhesively bonded to the paper strip. The inlay paper strip is a multi-ply paper strip or it is a folded paper strip. The inlay may be gummed on both flat sides thereof or it may be a backing-less adhesive strip.
In accordance with several further features of the invention, the paper strip is made of paper material having a primarily longitudinal fiber orientation parallel to a longitudinal extent of the tear strip; the adhesive is water-soluble; the tear strip is formed with longitudinally extending grooves; and/or the tear strip is corrugated in a transverse direction thereof. This makes the tear strip flexible in the crosswise direction and or in the longitudinal direction.
In other words, the objects of the invention are solved in that the tear strip is formed by at least one multiply folded paper strip, and the plies of the paper strip resting on one another are partially or fully adhesively bonded to one another.
The novel tear strip overcomes all the disadvantages of the prior art tear strip:
By the choice of paper thicknesses and the number of plies of paper, it can be made with any tensile strength and stiffness, thus enabling accurate adaptation to the thickness or quality of the paper of the paper web that is to be severed. Since there is no adhesive on the outside of the tear strip, no sticking together of the wound-up tear strip can occur. Since instead the adhesive is located only inside the tear strip, undoing of the adhesive bond by moisture, which lowers the tensile strength of the tear strip, is also averted.
A tear strip made from multi-ply paper strips glued together with a water-soluble adhesive are also more easily unraveled in the recycling process, and is therefore more readily recycled. In addition, such a tear strip when severed is severed along a virtually straight edge, so that no paper remnants that can cause functional problems in the feed channel are left behind. Since moreover such a tear strip has longitudinal edges which, while they extend in a straight line, are not sharp, an optimal course in the process of severing the paper web is thereby assured. Since furthermore such a tear strip has a virtually smooth surface, generally flat layers of adhesive adhere well enough to it that they cannot come loose. Finally, such a tear strip can be made in unlimited lengths.
In exemplary terms, a tear strip according to the invention is formed of a paper strip that is folded multiple times; the plies resting on one another are glued together with a water-soluble adhesive. The adhesive is located inside the tear strip, and the outsides of the tear strip are kept free of adhesive.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a tear strip for severing a moving paper web, 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 of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of the specific embodiment when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
FIGS. 1-9 are partial, perspective views of different embodiments of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the figures of the drawing in detail and first, particularly, to the first exemplary embodiment of FIG. 1, there is seen a tear strip formed of a paper strip 1 whose lateral regions 11 and 12 are folded over, above the middle region 10, onto one side such that their long edges rest tightly on one another. The plies resting on one another are glued together by means of a layer 13 of an adhesive. That tear strip, which has two plies, thus has long edges or longitudinal edges 14 and 15, formed by folds, with which the paper web is severed.
With reference to FIG. 2, a further exemplary tear strip is formed of a paper strip 2 whose lateral edges 21 and 22 are folded over one another above the middle region 20 and are glued to one another by means of adhesive layers 23. There is thus formed a three-ply tear strip, whose two side edges 24 and 25 form the severing edges. The tear strip of FIG. 2 has increased tensile strength as compared with the tear strip of FIG. 1, because it is a three-ply tear strip.
The tear strip shown in FIG. 3 differs from the tear strip shown in FIG. 2 in that the two lateral regions 31 and 32 of the paper strip 3 are folded over onto different sides of the middle region 30. This embodiment is an S-shape. Once again, the individual plies of the paper strip 3 are glued together by means of adhesive layers 33. The two side edges 34 and 35 form the severing edges.
In the tear strip of FIG. 4, the two lateral regions 41 and 42 of the paper strip 4 are bent over multiple times above the middle region 40; the individual plies of the tear strip, which is four-ply in form, are joined together by means of adhesive layers 43. As a result, even higher rigidity and tearing strength are attained. The tear edges are formed by the side edges 44 and 45.
With reference to FIG. 5, the exemplary tear strip of FIG. 1 may be improved (in terms of its strength) in that a reinforcing paper strip inlay 5 is provided in the paper strip 1 whose lateral regions 11 and 12 are folded toward one another. The tear strip is reinforced with the reinforcing paper strip 5, the width of which is virtually equal to the width of the tear strip and which is joined to the plies 10, 11, and 12 of the paper strip 1 by means of two adhesive layers 13. The inlay may also be formed by a backing strip of paper, which is coated on both sides with a water-soluble adhesive, i.e. by a two-sided gummed strip, or by a backing-less adhesive tape.
In FIG. 6, yet another tear strip is shown, which differs from the exemplary embodiment of FIG. 5 in that the paper strip 1 encloses three paper strips 51, 52, 53, located one above the other, which form a reinforcing inlay, and which are joined to the plies of the paper strip 1 by means of a plurality of adhesive layers 13.
In FIG. 7, a tear strip is shown which differs from the exemplary embodiment of FIG. 1 in that two paper strips 1 and 1a are glued together; the lateral regions 11a and 12a of the outer paper strip 1a are folded over on top of the folded paper strip 1 and are glued to the other plies by means of adhesive layers 13 located on the inside.
In FIG. 8, a tear strip is shown whose lateral regions 10, 11, 12 of FIG. 1 are so enclosed by a second paper strip 1b that the lateral regions 11, 12 and 11b, 12b of the two paper strips 1 and 1b are located on different sides of the tear strip.
To attain the requisite flexibility of such a tear strip, the tear strip may be embodied with profile features in the form of a corrugation in the crosswise direction. In FIG. 9, a tear strip 8 as in FIG. 8 is shown, which is corrugated in the crosswise direction and onto which a generally flat adhesive layer 9, which is needed for the severing operation, is applied. Since this adhesive layer 9 adapts to the corrugated nature of the tear strip, the disadvantages of the prior are nevertheless avoided.
A tear strip of this kind, made of paper, can be made in arbitrary lengths.
More specific information concerning the general field of this invention may be found in our copending application Ser. No. 08/544,072, which is herewith incorporated by reference. | A tear strip severs a moving paper web as it is being wound onto a drum, so as to enable the paper web to be wound onto an empty drum. The tear strip is made of paper. The tear strip is a multiply folded paper strip, and the plies of the paper strip resting on one another are at least partially adhesively bonded to one another. | 8 |
TECHNICAL FIELD
This invention relates to establishment of a telephone connection using Internet protocol (IP) to a station that is not currently connected to the Internet.
Problem
Data Network Protocol Telephony, such as Internet Telephony, (otherwise known as IP (Internet Protocol) Telephony) i.e., the routing of telephone calls through the Internet is now possible between two stations, both of which are connected on an active connection to the Internet. However, in the prior art, it is not possible to complete a call to a wireless powered-up station or a land-line station that at the time a call is originated, has no active connection to the Internet. With the increasing prevalence of both Internet service and cellular service, this is a serious limitation.
Solution
The above problems are solved, and an advance is made over the teachings of the prior art in accordance with the principles of this invention, wherein in response to a request to establish a data network protocol, such as an Internet Protocol (IP) telephone call to a wireless or wireline station that is not currently connected to the Internet, the station is notified and requested to initiate registration and connection to the Internet; after the station is so connected and registered, the IP telephone call can be completed.
In one specific implementation, if the called station is a wireless station, the wireless station is paged, and the paging message includes an indication that the page request is for an IP telephone call; in response to the paging request, the wireless station initiates a connection to a point of presence, hereinafter called a home agent, for terminating the incoming call within the Internet; the Internet then establishes a connection between the appearance of the incoming call at the input of the Internet, and this home agent. Advantageously, such an arrangement allows a suitably equipped cellular station to receive IP calls, even when the station, though powered-up, is not on an active connection to the Internet.
In accordance with one preferred embodiment of the invention, if the terminating cellular station moves, and attaches itself to a foreign agent, a connection is established within the Internet between the home agent and the foreign agent for communicating with the cellular station. Advantageously, the cellular station may move during the course of the conversation without losing the IP call.
If the called station is a wireline station not currently connected to a point of presence or home agent, the called station is alerted, without establishing a connection to a serving switch, with an indication that the called station should register on the Internet at a home agent for serving the called station. After the called station has registered and is connected to the home agent, the call is completed as in the prior art IP telephony procedures.
If the terminating wireline station has a Personal Computer (PC), there are a number of ways of alerting the PC without establishing a connection. A pre-programmed caller identification can be sent as a caller ID signal, and intercepted in the caller ID unit to generate an appropriate signal to the PC. Called number identification can be used to send either a special called number which can be interpreted by the called number identifier unit of the terminating subscriber as an indication to request a registration on the Internet, or an added number dedicated to this purpose can be used; in the latter case, this added number is stored in either the DDS or the ITHS, and is passed through the PSTN to the called number. A suppressed ringing connection can be used to access a telemetering interface unit, and this telemetering interface unit upon receipt of an appropriate data message can trigger the PC to request registration. If the terminating station is an ISDN, (Integrated Services Digital Network) station, the data message for causing the PC to request an Internet registration action can be passed as a control message over the D-channel. In all of these cases, no connection need actually be set-up in the PSTN; it is adequate if the Common Channel Signaling (CCS 7 ) network of the PSTN, transmits a message that the terminating switch understands and can act upon.
If the called station is a wireline station not currently connected to a point of presence or home agent, the called station is alerted, without establishing a connection to a serving switch, with an indication that the called station should register on the Internet at a home agent for serving the called station. After the called station has registered and is connected to the home agent, the call is completed as in the prior art IP telephony procedures.
In accordance with one preferred embodiment of the invention, the caller need not be a “dial-up” Internet station, but can be a wireless, or wireline connected to the Internet via the Public Switched Telephone Network, (wireless or wireline). Such a caller is connected in accordance with the principles of the prior art via an Internet Telephony Gateway, for performing the function of converting between circuit voice signals and IP packets. Other caller terminals may be directly connected via a data access network to a point of presence on the Internet.
BRIEF DESCRIPTION OF THE DRAWING(S)
FIG. 1 illustrates the configurations that can be served using Applicants' invention;
FIG. 2 illustrates the basic architecture of Applicants' invention; and
FIGS. 3-6 are flow diagrams, illustrating the process of Applicants' invention.
DETAILED DESCRIPTION
FIG. 1 illustrates the types of calls that can be served using the principles of Applicants' invention. The callers may be a wireless station 11 , connected to the Internet core network 1 through the wireless Public Switch Telephone Network (PSTN) 10 ; a wireline telephone station 13 , connected to the Internet via the wireline PSTN 12 ; a station 15 , comprising a PC (Personal Computer) 16 and an audio interface 17 , connected via a data-based wireline access network 14 ; and a wireless station 20 , comprising a wireless station 21 , a PC 22 , and an audio interface 23 , and connected via a data-based wireless access network to the Internet 1 . The Internet 1 is an Internet Protocol, (IP) based core network.
A receiving cellular wireless station 2 is connected to the Internet 1 , via a data-based wireless access network 6 . The receiving station 2 comprises a wireless station 5 , a PC 4 connected to the wireless station, and an audio interface 3 . In addition, another called customer station, wireline station 8 , comprising PC 28 connected to an audio interface 29 , is connected to the Internet through wireline PSTN 7 . Also, in addition, data-based wireline access network 25 can be used to access terminals, such as telephone station 35 or station 33 comprising PC 31 connected to an audio interface 32 . As is well known in the prior art, the data-based wireline access network 25 , and the wireline PSTN 7 , can be connected to terminals through cable systems which can deliver circuit signals, such as pulse code modulation (PCM), or data signals such as IP signals.
FIG. 2 is a diagram, illustrating the pertinent aspects of the architecture of Applicants' invention for a call to a cellular wireless station 2 , or to a wireline station 8 . Stations 11 and 13 are connected via a PSTN, (not shown), and an Internet Telephony Gateway 202 , and station 20 is directly connected to the Internet 1 , through software in or PC 22 of station 20 , for communicating with Internet Telephony Call Processing Proxy 201 in the Internet. Block 201 receives an identification of the called party. Consider first, the case of a wireless cellular station 2 . The identification is a telephone number, (an E.164 number as specified by the Standards). This number is received by an Internet Telephony Home Server (ITHS) 205 , which serves the same basic function as a Home Location Register (HLR) 203 in a wireless PSTN. The ITHS determines whether the called number is that of an IP telephony user, or a wireless or wireline PSTN user. If the received number is a wireless PSTN E.164 number, and not the number of an Internet telephony user, the ITHS 205 sends a query to HLR 203 , and the call is completed as in the prior art.
If the called number is that of an IP telephony user, the ITHS 205 translates the called number to a Network Access Identifier (NAI), and queries a Dynamic Directory Server (DDS) 209 , (using the NAI), to obtain the IP address of the called party. If the called party is already registered on the Internet, and the call is to a wireless station, the call is completed as in the prior art. If the DDS indicates that the called party is not already registered on the Internet, the ITHS communicates its information to Home Location Register (HLR) 203 , which responds with the identity of the Visitor Location Register 207 . If necessary, the HLR then queries VLR 207 in order to find the information necessary for paging the called party. A paging request is sent to the Mobile Switching Center, (not shown), which causes one or more base stations to page the called party in accordance with the principles of the prior art. The paging message contains an indication that the called party is being called on an IP telephone call. The message accompanying the paging is sent by receiving wireless station 5 , to PC 4 . In response to receiving this message, PC 4 activates software for processing this message. The receiving station 2 then transmits a request to register and establish a connect-ion to the Internet. A home agent 211 is assigned for the called party. (The home agent unit also serves 7 as a foreign agent if a hand-off requires the use of a new foreign agent for connect-ion to the wireless station). The called party is then connected to a Home Agent 211 , which communicates through the Internet with the calling party via IT Call Processing Proxy 201 , or Internet Telephony Gateway 202 .
Now, consider the case in which the called party is a wireline terminal such as terminal 8 . When the call arrives at the Internet Telephony Gateway 202 or the Internet Telephony Call Processing Proxy 201 , the ITHS is queried with E.164 telephone number. The ITHS translates this number to a network access identifier (NAI) and queries DDS 209 with that NAI. DDS 209 determines whether the specified NAI is already connected to the Internet, in which case the call proceeds as in the prior art, or whether the NAI is not at present connected to the Internet. In the latter case, the DDS reports the fact of non-connection to ITHS 205 . ITHS 205 then causes a signaling message to be sent from the switch serving the Internet Telephony Gateway 202 or the Internet Telephony Call Processing Proxy 201 via the channel signaling network of wireline PSTN 7 to the switch, (not shown), serving the called party 8 . The object of this message is not to establish a telephone communication, but to cause the serving switch to alert PC 28 of the called terminal 8 that the PC should initiate an Internet registration process in order to receive the call as an Internet Telephony call.
If the called station is a wireline station not currently connected to a point of presence or home agent, the called station is alerted, without establishing a connection to a serving switch, with an indication that the called station should register on the Internet at a home agent for serving the called station. After the called station has registered and is connected to the home agent, the call is completed as in the prior art IP telephony procedures.
In response to receipt of an indication that the terminating station should register on the Internet in order to receive an Internet Telephony call, the PC 28 initiates such a registration. Once the registration is completed, the DDS is informed of the registration of that NAI and the address in the Internet where that NAI can be found. The call is then completed from the Internet Telephony Gateway 202 , or the Internet Telephony Call Processing Proxy 201 through the Internet Network 1 to the PC of the called station.
FIGS. 3 and 4 are flow charts, illustrating the process of delivering an Internet Telephony call to a wireless cellular station, having Internet capabilities, but not registered on the Internet at this time. Calls to a station that is currently registered on the Internet are handled as in the prior art. One specific system for using Home Location Registers (HLRs) and Visitor Location Registers (VLRs) is illustrated; other systems can be readily adapted to the application of this invention.
A call is received at the Internet Telephony Gateway (FIG. 2, 202 ), from a non-IP station, such as station 11 or 13 , or is received at the IT Call Processing Proxy (FIG. 2, 201 ), from an IP station, such as station 15 or 20 of FIG. 2, (Action Block 301 ). The receiving entity finds the identity of the ITHS, (Block 205 , FIG. 2 ), that can serve this call based on the E.164 number of the called party, (Action Block 303 ). The receiving block then sends a request for routing information, including the E.164 number to the identified ITHS, (Action Block 305 ). The ITHS then obtains the Network Access Identifier, (NAI) of the called party and the identity of the serving Dynamic Directory Server, (Action Block 309 ), and sends a request to the identified DDS, including the NAI, (Action Block 311 ). If the identified subscriber is registered and connected to the Internet, then the IP address for that subscriber is obtained, returned to the ITHS, and the call is completed as in the prior art, (Action Block 313 ). If the IT subscriber is not connected, then a not-connected indication is sent back from the DDS to the ITHS, (Action Block 317 ). The ITHS has an indicator that the called party is wireless. The rest of FIG. 3, relates to completing calls to a wireless cellular station. The ITHS then sends a request to the HLR, (identified by the E.164 number of the called customer), requesting routing information, and specifying the E.164 number of the called customer, and an indication that this is for an Internet Telephony Call, (Action Block 319 ). The HLR retrieves the International Mobile Subscriber Identifier (IMSI), and the Visitor Location Register (VLR), of the called customer, (Action Block 321 ). The HLR then sends a message to the VLR to request a paging action, specifying the IMSI for the called party, and the fact that this is for an Internet Telephony Call, (Action Block 323 ). The VLR in response to this request, which includes an indication of an Internet Telephony call, identifies the mobile switching center (MSC), that is currently serving the called station, and requests that the identified MSC through the appropriate base station(s), page the mobile, including in the paging message an indication that this is an Internet Telephony Call, (Action Block 327 ). The base station(s) performed the page, (Action Block 329 ), and the called station in response to receiving the page, initiates a registration on the Internet, (Action Block 331 ).
FIG. 4 illustrates the process of registration of the terminating station, and address delivery to that station. The called terminal initiates a registration, specifying its network access identifier, (Action Block 401 ). The receiving network access server processes the log-in, assigns an IP address, checks to make sure that the subscriber has Internet Telephony services, and will act as the initial home agent for the call, (Action Block 403 ). The network access server then notifies the Dynamic Directory Server of the registration, identifying it by the called customer's NAI, and provides the IP address that has been assigned to the called customer station, (Action Block 405 ). The DDS stores the IP address for this NAI, and sends its identity to the Internet Telephone Home Server, (Block 203 , FIG. 2, Action Block 407 ). The DDS sends a message to the ITHS indicating the NAI, the IP address of the DDS, and the IP address of the called customer station, (Action Block 409 ). The ITHS responds with an acknowledgment, (Action Block 411 ), and transmits to the IT Gateway, or the IT Call Processing Proxy, whichever had initiated the request, the IP address of the called customer station, (Action Block 413 ). Now, the call can be completed as in the prior art, (Action Block 415 ).
FIGS. 5 and 6 illustrate the process of delivering calls to unconnected wireline subscribers who subscribe to Internet. An Internet Gateway or a Proxy for representing the originating terminal in the Internet, receives an IP telephony terminating call, (Action Block 501 ). The Gateway or Proxy finds the identifier of the ITHS associated with the called number based on the received E.164 number, (Action Block 503 ). The Gateway or Proxy sends a routing information request, including the E.164 number, to the identified ITHS, (Action Block 505 ). The ITHS translates between the E.164 number and the terminating subscriber network access identifier (NAI), and retrieves the identity of the Dynamic Directory Server for that subscriber, (Action Block 507 ). The ITHS sends a request for an IP address to the identified Dynamic Directory Server (DDS), using the identified NAI as the parameter for making the request, (Action Block 509 ). If the IT subscriber is already IP connected to the network, then the IP address is retrieved, and the call proceeds to completion as in the prior art. If the terminating DDS finds that the terminating number is that of a terminating IT subscriber who is not at this time IP connected, the DDS must respond back to the ITHS, (Action Block 513 ). In this case, the DDS responds with a message indicating that the identified NAI is not IP connected, (Action Block 515 ). The ITHS checks for the characteristics of this call, (Action Block 517 ). If this is not a wireless termination, then the ITHS saves the identity of the IT Gateway/Proxy IP address for this NAI, (Action Block 519 ). The ITHS sends a message back to the IT Gateway or Proxy, including the E.164 number, and an indication that the called customer is at present unconnected to the Internet, but has IP telephony service, (Action Block 521 ). The IT Gateway, or Proxy causes its serving switch to send a common channel signaling message to the terminating switch identified by the E.164 number, indicating that this is an IP call, (Action Block 523 ). In conformance with normal call processing, the terminating switch checks whether the terminating subscriber has this kind of service, (Test 525 ). If not, the terminating switch causes a call failure message to be sent to the IT Gateway or Proxy and the call fails, (Action Block 527 ). If so, then the terminating switch sends an IP call indication message to the terminating subscriber's telephone set, (Action Block 529 ). The terminating subscriber's telephone set forwards an Internet connection request to the terminal, (PC), of the called customer to initiate registration to the Internet, (Action Block 531 ).
FIG. 6 illustrates the process of registering the wireline station, (the called terminal), on the Internet, and completing the call once the called terminal has registered. The IT terminal dials to access its network access server, (NAS), (Action Block 601 ). The IT terminal then initiates registration providing its NAI to the NAS, (Action Block 603 ). The NAS processes the log-in request, which will involve a dialogue with the IT terminal, assigns an IP address, and checks whether the calling subscriber has IP telephone service, (Action Block 605 ). The NAS will act as a router for the call, and will also serve as the home agent/foreign agent, ( 211 , FIG. 2 ), for the call. The NAS sends an IP telephone registration, including the NAI of the terminating customer, and the IP address assigned to that customer to the Dynamic Directory Server, (Action Block 607 ). The DDS stores the IP address for the NAI, and sends its identity to the ITHS, (Action Block 609 ). The DDS then sends the NAT of the called terminal the IP address of the DDS, the IP address which has been assigned to the terminal, and the Gateway address, saved earlier, to the ITHS, (Action Block 611 ). The ITHS then associates the NAI with the IP address of the DDS, (Action Block 613 ). The ITHS then sends a location message response back to the DDS as an acknowledgment, (Action Block 615 ). The ITHS sends the routing information response requested in Action Block 521 (FIG. 5) to the IT Gateway or Proxy, (Action Block 617 ). This response consists of the IP address of the called terminal. The DDS sends the IP telephony registration response to the network access server, (Action Block 619 ). The NAS then sends a registration response to the called terminal, including the IP address that has been assigned to the terminal for the call, and also including the NAI for verification, (Action Block 621 ). Call set-up to a registered terminal can now proceed as in the prior art under the control of the Gateway or Proxy, (Action Block 623 ).
The above description is of one preferred embodiment of Applicants' invention. Many other embodiments will be apparent from this description to those of ordinary skill in the art without departing from the scope of the invention. The invention is only limited by the attached claims. | A method and apparatus for establishing a connection to a customer telecommunications station, having Internet service, but not currently connected to the Internet. In response to receipt by the Internet of a call to that station, the station is located for the purpose of notifying the station of the call. If the called station is a wireless station, the paging message includes an indication that the page is for an Internet Protocol, (IP) telephone call. For wireline stations, other alerting techniques are used to indicate that a station is being called on an Internet call. In response to receiving the notification, the called station automatically logs on to the Internet, and is assigned a temporary Internet Protocol address, (IPA). A connection is then established between the access point of the caller on the Internet, and the access point of the called customer. Advantageously, an Internet subscriber need not be presently connected to the Internet to receive IP telephone calls. | 7 |
RELATED APPLICATIONS
[0001] This application claims priority to U.S. provisional patent application Ser. No. 61/548,829, filed 19 Oct. 2011, the contents of which are incorporated herein by reference.
FIELD
[0002] The present technology relates to an ergonomic hand grip that provides shock absorption and reduces fatigue. More specifically, the present technology is a hand grip of varying thickness to permit support while also absorbing shock and vibration.
BACKGROUND
[0003] Many hand held devices have hand grips that provide some shock absorption. Similarly, sporting equipment, such as golf clubs and bicycles, has grips that reduce the force of impact and damp vibration.
[0004] For example, US Publication No. 20110219909 discloses a handlebar with dampers underneath the hand grips. The dampers are preferably constructed of an elastomeric or rubber-type material whereas the body of the handlebar assembly is formed of a more rigid material, such as a metal, like steel or aluminum based materials, and/or carbon fiber material. It is disclosed that the dampers are formed of a more pliable and resilient material having durometer values between about A25, a durometer value comparable to a rubber band, and about A55, a durometer value comparable to a door seal. Also disclosed are supplemental or optional grip assemblies that are configured to cooperate with handlebar assembly and dampers. The core of the grip assemblies includes a window or opening that extends in a longitudinal direction along a substantial portion of core. When the core is engaged with body of handlebar assembly, the opening overlies and exposes all or a substantial portion of the hand side of the dampers underneath. This allows the vibration or oscillation damping performance of handlebar assembly to be augmented by the vibration or oscillation damping performance attributable to grip assembly. The grip has an ear that extends in a radially outward direction from core near the outboard end of the core. This is for indexing the grip with respect to the core.
[0005] In US Publication No. 20090072455 a damper is disclosed for various applications, including sporting equipment. The damping portion comprises a first tube, a second tube and a layer of resilient material configured so that the first tube is disposed about the second tube, and the layer of resilient material is positioned between the first and second tubes.
[0006] US Publication No. 20040048701 discloses a vibration absorbing grip including a grip body formed by a multi-layer material. The material preferably includes a first elastomeric layer of vibration absorbing material which is substantially free of voids therein. A second elastomeric layer which includes an aramid material therein and is disposed on the first elastomeric layer. The aramid material distributes vibration to facilitate vibration damping. A third elastomeric layer is disposed on the second elastomeric layer and is adapted to be gripped by a user.
[0007] U.S. Pat. No. 6,959,469 discloses a pliable handle for a hand held device. As in the previous mentioned patents, there is provided a core member and an outer sheath, with gel being disposed between the core member and the outer sheath. The pliable handle is designed to deform and conform to the shape of the user's hand. The applied force causes movement of the gel, the pliable handle having a “memory effect” that causes the handle to temporarily deform for a period of time to the deformed shape before the handle returns to its original shape.
[0008] Some grips are designed to provide different amounts of damping in different parts of the hand grip, by using materials of differing durometer. For example, US Publication No. 20090271951 discloses a hand grip for hand tools and the like contains a plurality of elastomeric compositions to protect the users hand during use. As proposed a plurality of gel inserts are provided with varying degrees of hardness and density to provide an improved ergonomic design while insuring the integrity of the handle. Three layers are provided with the innermost layer being the hardest with a hardness of approximately 95 on the A Durometer scale, the middle layer having an intermediate hardness of approximately 55 on the A Durometer scale and the outermost layer being the softest with a hardness of approximately of 20 on the A Durometer scale.
[0009] The shape of the hand grip can also play a role in decreasing fatigue. For example, US Publication No. 20050039565 discloses an ergonomic hand grip. The first component is an outward protrusion of the rear portion of the grip, that is positioned towards the portion of the palm that lies under the fourth and fifth (ring and pinkie) fingers. This disperses pressure over Guyon's Canal (Ulnar Canal). The second component is an outward protrusion of the front portion of the grip, which may be positioned under the index, middle, ring and pinkie fingers. The protrusions of the front and rear portions increase the diameter of the grip itself, and improve the leverage of the handgrip. An inward curve of the grip under the thumb area may optionally be provided.
[0010] US Publication No. 20090114257 discloses the use of a damping compound that is resilient and is formed in part over the handle of a walking aid. The handle is ergonomically shaped.
[0011] As disclosed in WO/2010/069070, an ergonomic hand grip provides an ergonomic shaped handle having elastomeric inserts of various densities (durometers) on the grip surface area that complement the hand during usage of an assistive mobility device, such as a crutch or walking stick.
SUMMARY
[0012] A simplified hand grip that is ergonomically shaped and shock absorbing is provided. The simplified design allows for ease of manufacturing by reducing both the number of steps required and the range of materials used. At the same time, the hand grip provides superior support, vibration damping and impact absorption, thereby reducing fatigue for the user. Both ulna nerve irritation and wrist compression are reduced. The hand grip comprises an optional inner core, a structural layer made of a single elastomeric material, formed into a body and a fin and an outer covering made of a single material. The structural layer is harder than the outer layer. The fin provides support to the thenar eminence during the heel strike of a user's hand, while at the same time, also cushions the heel strike by flexing in response to the pressure exerted. The fin extends laterally and longitudinally from the body at the proximal and central regions and decreases in thickness distally. A concave region between the fin tip and the body accept a user's thumb. The body has a narrow proximal region, a narrow distal region and a thicker central region. The body has a generally cylindrical central bore for locating the grip on a tube, such as a bicycle handlebar or a handle of an assistive mobility device. The body has a distal end and a proximal end. The distal end has a locking member for locking the hand grip over the tube and the proximal end is sized to accept an end cap.
[0013] It is preferred that the fin has a lateral offset relative to a vertical axis of the hand grip and that offset be about 15 to about 30 degrees.
[0014] It is advantageous for the core to have a durometer rating of at least about 85 A, the structural layer to have a durometer rating of about 30 A to about 50 A and the outer layer to have a durometer rating of about 20 A to about 35 A.
[0015] Cushioning by the fin is promoted by having the flexibility of the fin increase toward the fin tip.
[0016] It is preferred that the fin has a longitudinal depression and is integral with the body as this allows the thenar eminence to fit comfortably on the fin and the hand to rest comfortably on the grip.
[0017] In order to allow for adjustments to be made, the hand grip preferably has a ciamp in the vicinity of the proximal end, for clamping the hand grip to the handle.
[0018] It is preferred, for ease of putting the grips on the handle and aligning the grips, that the core has slots and a retainer aperture in the vicinity of the proximal end.
[0019] In another embodiment, an assembly for use with an assistive mobility device is provided. The assembly comprises a handle and an ergonomic hand grip. The hand grip comprises a body, a fin, and a clamp. More specifically, the body comprises a proximal end, a distal end, and a core therebetween, the core defining a central bore along a longitudinal axis for accepting the handle, the core having slots and a retainer aperture in the vicinity of the proximal end. Both the body and fin comprise a structural layer of a single material of variable thickness, and an outer layer of a single material of essentially consistent thickness. The core has a durometer rating of at least about 85 A, the structural layer has a durometer rating of about 30 A to about 50 A and the outer layer has a durometer rating of about 20 A to about 35 A. The fin is shaped to flexibly support a user's thenar eminence, extends from the body laterally and longitudinally, terminates in a fin tip distally, has a lateral offset relative to a vertical axis of the hand grip of about 15 to about 30 degrees, has a lateral depression, increases in flexibility distally and is integral with the body. The clamp adjustably retains the hand grip to the handle.
[0020] In yet another embodiment, an ergonomic, force-absorbing hand grip for use on a bicycle handlebar is provided. The hand grip comprises:
a body, the body comprising: a structural layer of variable thickness; an optional core; a central bore for accepting the handlebar; an outer layer of essentially consistent thickness, the structural layer being harder than the outer layer; an inboard end; an outboard end, and a centrally located protrusion; a fin, the fin being integral with and extending laterally from the body, terminating in a distally disposed tip, terminating in a distally disposed tip, and having a fin return defining, with the body, a concave region, and comprising: the structural layer; and the outer layer, the structural layer of variable thickness and the outer layer of essentially consistent thickness; and a clamp, the clamp for releasably retaining the hand grip on the handlebar and for allowing for adjustment of the grip; a clamp, the clamp for releasably retaining the hand grip on the handlebar and sized to fit over the inboard zone of the core,
wherein differences in thickness in the structural layer provide differences in force-absorption in the hand grip.
[0026] For ease of construction, it is preferable that each of the core (if present), structural layer and the outer layer is composed of a single material. The material used for the core has a durometer rating of at least about 85 A, the material used for the structural layer has a durometer rating of about 30 A to about 50 A and the material used for the outer layer has a durometer rating of about 20 A to about 35 A.
[0027] It is preferable that the fin is shaped to flexibly support a user's thenar eminence and has a lateral offset relative to a vertical axis of the hand grip of about 15 to about 30 degrees.
[0028] To assist in locating a user's hand, the hand grip may have a flange in the vicinity of the inboard end.
[0029] For safety when traveling in traffic, the hand grip may have a light in the outboard end.
[0030] If the hand grip is to be used on a road bike, it is preferable that the body comprises an upper section and a lower section. In order to attach the upper section to the lower section, mating members may be disposed on a longitudinal margin thereof.
[0031] For ease of construction, it is preferable that the fin be integral with the lower section of the body.
[0032] For ease of assembly, it is preferred that the hand grip be provided with two clamps, the clamps being two piece clamps for fitting over the hand grip and handlebars.
FIGURES
[0033] FIG. 1 is a perspective view of an embodiment of the present technology, with the proximal end exploded.
[0034] FIG. 2 is a longitudinal section view of the embodiment of FIG. 1 .
[0035] FIG. 3 is a plan view of the fin of the embodiment of FIG. 1 .
[0036] FIG. 4 is a proximal end view of the fin on the body.
[0037] FIG. 5A is a distal end view of the fin on the body and FIG. 5B is a sectional view taken along line 5 B in FIG. 3 .
[0038] FIG. 6 is a perspective view of the embodiment of FIG. 1 , mounted on a handle.
[0039] FIG. 7 is a perspective view of an alternative embodiment of the present technology, mounted on a bicycle handlebar, with the outboard end exploded.
[0040] FIG. 8 is a perspective view of an alternative embodiment of the present technology.
[0041] FIG. 9 is a clamshell view of an alternative embodiment of the present technology.
DETAILED DESCRIPTION
Definitions
[0042] Distal refers to away from the body in relation to a crutch or assistive mobility device.
[0043] Proximal refers to toward the body in relation to a crutch or assistive mobility device.
[0044] Outboard in the context of a bicycle refers to the direction that is toward the end of the handlebar.
[0045] Inboard in the context of a bicycle refers to the direction that is toward the stem of the handlebar.
DESCRIPTION
[0046] A hand grip, generally referred to as 10 is shown in FIG. 1 . The hand grip has a body 12 and an integral fin 14 . The body has a central region 16 , a distal region 18 , a proximal region 20 , a distal end 22 and a proximal end 24 . The fin 14 extends distally from the proximal 20 and central region 16 . The central region 16 has a protuberance 26 . A split ring or C-type clamp 28 is located at the proximal end 24 and encircles the innermost layer or core 60 of the hand grip 10 . The clamp 28 has a fastener 30 that when tightened, compresses the clamp 28 and the core 60 . The fastener 30 extends through a clamp aperture 61 and a vertically disposed retainer aperture 62 to assist in aligning the hand grip 10 and clamp 28 . The distal end 22 terminates in a flange 32 .
[0047] As shown in FIG. 2 , the distal and proximal regions, generally shown as 18 and 20 , are thinner in cross sectional area than is the central region, generally referred to as 16 , with a gradual increase in cross sectional area in the distal region 18 and the proximal region 20 , leading to the protuberance 26 . The cross sectional area also increases around the distal end 22 in the flange 32 . A central bore 36 extends along a longitudinal axis 38 of the hand grip 10 between a distal aperture 40 and a proximal aperture 42 . The dimensions of the body are as follows:
the length is about 110 to about 150 mm long, preferably about 120 mm to about 140 mm, more preferably about 130 mm long; the width is about 25 to about 35 mm wide, preferably about 30 mm wide at the narrowest point, increasing to about 35 mm to about 45 mm wide, preferably about 38 mm wide, including at the flange 32 and the protuberance 26 ; and the diameter of the central bore 36 is about 20 to about 25 mm in diameter, preferably about 22 mm.
[0051] Also shown in FIG. 2 , the innermost layer of the hand grip 10 is a hard plastic core 60 , having a durometer rating of at least about 80, preferably about 85 and more preferably about 85 to about 90 on the A durometer scale. Alternatively, the core 60 is integral with the structural layer 70 and therefore has the same durometer rating as the structural layer 70 . To be clear, either the structural layer 70 or the core 60 form the inner layer 60 and the inner layer 60 defines the central bore 36 . The central bore 36 of the core 60 is sized to fit snugly over the tube 50 . As shown in FIG. 1 , the proximal zone 64 of the core 60 has at least one slot 66 extending into the core 60 . The slot allows the circumference of the core 60 to be reduced under the pressure of the clamp 28 , thereby retaining the hand grip 10 in place.
[0052] As shown in FIG. 2 , the middle layer of the hand grip 10 is a structural layer 70 . The structural layer 70 is composed of a single elastomeric thermoplastic, such as, but not limited to Ethylene Vinyl Acetate. The material can be foam or a soft plastic polymer or alternatively, a high-density polyethylene (HDPE), such as ThermoLyn™ RCH 500. It is formed into the body 12 , the protuberance 26 , the fin 14 and the flange 32 .
[0053] The material used in the structural layer has a durometer rating of about 30 to about 55, preferably about 35 to about 50 and more preferably about 40 to about 45 on the A durometer scale. Rather than using a number of materials of differing durometer ratings to provide differences in the degree of support and damping, the present technology uses differences in thickness to provide differences in the degree of support and damping. This simplifies construction of the hand grip and provides superior support, vibration damping and impact absorption, thereby reducing fatigue for the user.
[0054] With regard to the body 12 , the middle layer 70 is about 0.5 mm to about 2 mm thick, preferably about 1 to about 1.5 mm thick on the distal 18 and proximal regions 20 of body 12 , increasing gradually to about 1 mm to about 2.5 mm, preferably about 2 mm thick at the protuberance 26 . The distal end 22 terminates in a flange 32 of about 5 mm thick.
[0055] With regard to the fin 14 , the middle layer 70 is about 7 mm to about 12 mm, preferably about 8 mm to about 10 mm, more preferably 9 mm thick on the proximal base 110 (see FIG. 4 ), and is about 0 mm to about 0.5 mm preferably 0 mm thick on each of the distal base 118 and the fin tip 102 (see FIG. 5 ).
[0056] An outer layer 82 covers the structural layer 70 . It is a washable material and can be provided in a number of colours. The material is preferably a single elastomeric thermoplastic, such as, but not limited to Ethylene Vinyl Acetate (EVA). The preferred EVA product is Lunalastik™, a product used in making orthotics. It has a density of approximately. 0.23 g/mm 3 and a durometer rating of about 25 on the A scale. Other durometer ratings that are acceptable are about 20 to about 35 and preferably about 22 to about 30. The outer layer 82 is a uniform thickness in the range of about 0.5 to about 2 mm, preferably about 0.5 to about 1.5 mm and most preferably about 1 mm. If additional padding is required, different thicknesses can be used rather than using materials of different durometer ratings. This simplifies construction the hand grip and provides superior support, vibration damping and impact absorption, thereby reducing fatigue for the user.
[0057] When used with mobility devices, the smooth outer layer 82 is preferred, while sculpting may be preferred for bicycles. This can be in the form of ridges, dimples, waffles or any other surface contour, as would be known to one skilled in the art. In this case, the outer layer 82 is made of a rubberized or rubbery layer. The durometer ratings are about 20 to about 35 and preferably about 22 to about 30 on the A durometer scale.
[0058] The fin 14 flexes in response to force. An average person will cause the fin to deflect between about 3 mm to about 6 mm, more specifically about 4 mm to about 5 mm, with the deflection increasing distally. This damps the impact of the hand on the hand grip 10 , whether as a result of striking a cane, crutch or walking stick on the ground, or as a result of a bicycle traveling over rough terrain.
[0059] Details of the fin 14 are shown in FIGS. 3 , 4 , and 5 . As shown in FIG. 3 , which is a plan view, the fin, generally referred to as 14 has a ridge 100 , a tip 102 , a fin return 104 , and a concave region 106 . The dimensions are as follows:
the ridge 100 is about 70 mm to about 90 mm long (along the longitudinal axis 38 ), preferably about 75 mm to about 85 mm, most preferably 80 mm long; about 15 mm to about 35 mm high (normal to the longitudinal axis 38 ), preferably about 20 mm to about 30 mm, most preferably 25 mm high at the lowest point, increasing in a curvilinear manner to the tip 102 ; the tip 102 is about 35 mm to about 55 mm high (normal to the longitudinal axis 38 ), preferably about 40 mm to about 50 mm, most preferably about 45 mm high at the highest point; and the fin return 104 defines the concave region 106 between the fin 14 and the body, generally referred to as 12 , the concave region being about 15 mm to about 25 mm, preferably 20 mm wide between the underside of the fin 14 and the body 12 and about 10 mm to about 15 mm deep (along the longitudinal axis). The thumb of the user sits in the concave region 106 . The dimensions of the fin 14 and body 12 are such that the user is able to align the first joint of their thumb with the inner margin 108 of the concave region 106 and wrap their thumb at least partially around the body 12 .
[0063] As shown in FIG. 4 , which is a proximal end view, the fin, generally referred to as 14 , has a ridge 100 , a proximal base 110 and a lateral offset 112 . Notably, the fin 14 decreases in width laterally i.e. from the proximal base 110 to the ridge 100 . The dimensions are as follows:
the ridge 100 is about 4 mm to about 6 mm, more preferably about 5 mm; the proximal base 110 is about 7 mm to about 14 mm wide, preferably about 8 mm to about 12 mm, more preferably 10 mm wide; and the lateral offset 112 is about 15 to about 30 degrees, more preferably about 20 to about 25 degrees and most preferably at 23 degrees from a vertical axis 114 . The offset mimics the angle at which the user's thumb naturally extends from the remainder of the user's hand.
[0067] As shown in FIG. 5A , which is a distal end view, the fin 14 has a distal base 118 , a fin tip 102 , and a longitudinal depression 116 with each of the fin tip 102 and the inner margin 108 of the concave region 106 preferably lacking the structural layer 70 . As shown in FIG. 5B , the fin 14 decreases in width from the distal base 118 to the fin return 104 and the fin tip 102 . As can be seen by comparing the dimensions of the distal base 118 and the proximal base 110 , the fin decreases in width from the proximal base 110 to the distal base 118 . The dimensions are as follows:
the distal base 118 is about 0.5 mm to about 4 mm wide, preferably 1 mm to about 3 mm, more preferably 2 mm wide; the fin tip 102 is about 1 mm to about 2.5 mm wide, preferably 1.5 mm to about 2 mm wide, more preferably 2 mm wide; the fin return 104 is about 1 mm to about 2.5 mm wide, preferably 1.5 mm to about 2 mm wide, more preferably 2 mm wide; and the longitudinal depression 116 is formed to rest the user's thenar eminence and is about 10 mm deep decreasing proximally to nothing over about 30 mm.
[0072] FIG. 6 shows a hand grip 10 on a tube or bar 50 . This may be, for example, but not limited to a handle or a crutch hand support. The clamp 28 holds the hand grip 10 in place on the handle 50 . The flange 32 extends radially outward in the vicinity of the distal end 22 to assist in hand placement. An end cap 54 is located in the distal aperture 40 .
[0073] The hand grip 10 is ergonomically designed. The heel of a user's hand rests on the fin 14 , while the thumb fits around the hand grip 10 at the distal region 18 . The protuberance 26 fits into the palm of the hand, providing cushioned support. The fourth and fifth finger close around the hand grip 10 at the proximal region 20 . As there is a gradual increase in cross sectional area in the distal 18 and proximal 20 regions, differences in hand sizes can be accommodated by shifting the hand on the hand grip 10 until a comfortable fit is found. Additionally, placement of the hand grip 10 on the tube 50 can be optimized by rotating the grip 10 and by moving it longitudinally along the tube 50 . Once the hand grip 10 placement is optimized, the clamp 28 is tightened over the hand grip 10 and tube 50 , immobilizing the hand grip 10 .
[0074] As shown in FIG. 7 , when used on a bicycle handlebar 150 , the clamp 28 may be located on the inboard end, generally referred to as 122 or may be on the outboard end, generally referred to as 124 . The fin tip 102 extends towards the inboard end 122 . The core 60 has an inboard zone 164 that extends beyond the structural layer 70 and the outer layer 82 to allow for the clamp 28 to tighten around the core 60 , just as the clamp is tightened around the proximal zone 64 of the core 60 when used on the handle 50 of an assistive mobility device. The inboard zone 164 of the core 60 has at least one slot 66 extending into the core 60 . The slot allows the circumference of the core 60 to be reduced under the pressure of the clamp 28 , thereby retaining the hand grip 10 in place. The clamp 28 has a fastener 30 that when tightened, compresses the clamp 28 and the core 60 . The fastener 30 extends through a clamp aperture 61 and a vertically disposed retainer aperture 62 to assist in aligning the hand grip 10 and clamp 28 . A flange 132 is located in the vicinity of the inboard end 122 . The flange 132 extends radially outward to assist in hand placement. An end cap 54 is located in the outboard aperture 140 . The outboard end 124 may be retained with a clamp 56 and fastener 58 . As would be appreciated, there is a left and a right hand grip 10 , each being mirror images of the other.
[0075] As shown in FIG. 8 , the end cap 54 can be replaced with a light 220 and power source 222 . The power source may be integral with the light, or may be separate, for example, a separate battery. A switch 224 is provided for turning the light 220 on and off. The switch can be pressure activated or motion activated. It may be separate from the light, as shown, or integral to the light. The light provides a safety feature as it shines in the direction of travel if mounted on an assistive mobility device and at right angles to the direction of travel if mounted on a bicycle, allowing motorists to see a user crossing a road in front of them.
[0076] In an alternate embodiment, the body 12 of the hand grip 10 is split longitudinally into two sections, a body upper section 212 and a body lower section 213 , as shown in FIG. 9 . Each of the core 60 , structural layer 70 , and outer layer 82 are configured to allow the hand grip 10 to be fitted on the handlebars of road bikes, similarly to affixing aerobars. The core upper section 230 and the core lower section 232 have mating members 234 . The mating members are preferably releasable and are a tongue in groove type of mating members. The structural layer upper section 240 abuts the structural layer lower section 242 . Similarly, the outer layer 82 , or cover has an outer layer upper section 250 that abuts an outer layer lower section 252 . The fin 14 is preferably located on one of the sections and is not split. Two piece clamps 260 with fasteners 262 for tightening the clamps 260 fit over the inboard end 270 and the outboard end 272 of the core 60 , which extend beyond the structural layer 70 and outer layer 82 , to allow the hand grip 10 to be retained on the handlebar 50 close to the stem. As would be appreciated, there is a left and a right hand grip 10 , each being mirror images of the other.
[0077] The foregoing is a description of an embodiment of the present technology. As would be known to one skilled in the art, variations that do not alter the scope of the technology are contemplated. For example, the core may be formed from the structural layer, resulting in the hand grip being two layers—the structural layer and the outer layer. This would be a preferable design if injection molding is used. The split ring clamps may be replaced with two piece clamps or other clamps that function to retain the grips. The grips may be permanently affixed to the handles or bars, using for example, but not limited to, an adhesive. The slots in the core may be replaced with a series of slits or a more malleable material may be used to construct the core. The hand grip can be used on any device or apparatus where load bearing on the hands occurs, for example, but not limited to, exercise equipment, walking sticks, and walkers. | A hand grip for use on a handle of an assistive mobility device or a bicycle has a body and an integral fin. Both are designed to damp vibration and reduce the force experienced by a user's hand. This is accomplished by using different thicknesses of an elastomeric material in the structural layer of the hand grip and by designing the fin to flex. The grip is covered with a soft elastomeric outer layer that provides additional cushioning. | 1 |
FIELD OF THE INVENTION
The field of this invention is control systems for downhole valves and more particularly for subsurface safety valves where the system is tubing pressure insensitive.
BACKGROUND OF THE INVENTION
Subsurface safety valves are used in wells to close them off in the event of an uncontrolled condition to ensure the safety of surface personnel and prevent property damage and pollution. Typically these valves comprise a flapper, which is the closure element and is pivotally mounted to rotate 90 degrees between an open and a closed position. A hollow tube called a flow tube is actuated downwardly against the flapper to rotate it to a position behind the tube and off its seat. That is the open position. When the flow tube is retracted the flapper is urged by a spring mounted to its pivot rod to rotate to the closed position against a similarly shaped seat.
The flow tube is operated by a hydraulic control system that includes a control line from the surface to one side of a piston. Increasing pressure in the control line moves the piston in one direction and shifts the flow tube with it. This movement occurs against a closure spring that is generally sized to offset the hydrostatic pressure in the control line, friction losses on the piston seals and the weight of the components to be moved in an opposite direction to shift the flow tube up and away from the flapper so that the flapper can swing shut.
Normally, it is desirable to have the flapper go to a closed position in the event of failure modes in the hydraulic control system and during normal operation on loss or removal of control line pressure. The need to meet normal and failure mode requirements in a tubing pressure insensitive control system, particularly in a deep set safety valve application, has presented a challenge in the past. The results represent a variety of approaches that have added complexity to the design by including features to. insure the fail safe position is obtained regardless of which seals leak. Some of these systems have overlays of pilot pistons and several pressurized gas reservoirs while others require multiple control lines from the surface in part to offset the pressure from control line hydrostatic pressure. Some recent examples of these efforts can be seen in U.S. Pat. Nos. 6,427,778 and 6,109,351.
Despite these efforts a tubing pressure insensitive control system for deep set safety valves that had greater simplicity, enhanced reliability and lower production cost remained a goal to be accomplished. The present invention provides for a tubing pressure insensitive operating piston. It neutralizes the hydrostatic forces in the control line to a significant extent while running a single control line to the surface. It provides a low pressure compressed gas volume to allow the piston to move when such movement reduces the volume of a cavity between piston seals. These and other features of the present invention will become more apparent to those skilled in the art from a review of the description of the preferred embodiment and the associated drawing of the control system, while recognizing that the full scope of the invention is to be found in the claims.
SUMMARY OF THE INVENTION
A control system for a downhole tool, such as a subsurface safety valve, features an operating piston that is insensitive to tubing pressure in the valve. The hydrostatic forces from the single control line from the surface are significantly reduced with a branch line to a piston bottom that is slightly smaller than the piston top. A variable volume between piston seals is connected to a low pressure compressible fluid reservoir to permit piston movement. The piston can be modular to facilitate assembly or bore offsets in the valve body. Failsafe closure upon seal failures is contemplated.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic system diagram of the control system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention can be used as a control system for a subsurface safety valve (SSSV) or for that matter other types of downhole tools that are hydraulically operated from the surface, generally via a control line 10 . In a SSSV application the end component is a flapper 12 that is pushed open by a flow tube 14 that moves against the bias of a power spring 16 . Since the present invention has applications beyond SSSVs any reference to flow tube is intended to generically refer to a part of a tool that is actuated by a piston assembly 18 of a control system. Since those skilled in the art are well aware of common components of SSSVs, they are omitted from the drawing to allow greater clarity in understanding the operation of the control system. For example, it is well known that the flapper 12 in the position shown in FIG. 1 is in the closed position against a seat that surrounds a passage in a valve housing. That passage is exposed to internal tubing pressure while being isolated from pressure in the control line 10 . The flow tube 14 and parts of the piston assembly 18 are similarly exposed to tubing pressure in the passage. Only a portion of the valve housing adjacent the piston assembly 18 is shown for clarity.
With that as an introduction, it can be seen that an upper housing 20 is juxtaposed opposite a lower housing 22 . They may be in one piece or two pieces that are connected. There are opposed spaced bores 24 and 26 that accept the piston assembly 18 . Preferably, the bores 24 and 26 are aligned but some offset can be accommodated with a modular design of the piston assembly 18 . A connector 28 can be used to connect upper piston 30 to lower piston 32 . Due to the channels at the ends of connector 28 the upper piston 30 can be connected to the lower piston 32 with a centerline offset. Although a rod piston design is preferred, other piston shapes are contemplated.
Lower piston 32 has a seal 34 to define a third variable volume chamber 36 . Control line 10 has a branch 38 connected at connection 40 to chamber 36 and a branch 39 connected to connection 46 . They form a junction 41 in close proximity to upper housing 20 . Options exist as to how to route branch 38 . It can be routed so that connection 40 is exposed to tubing pressure that affects the flow tube 14 and the flapper 12 , for example. Optionally, branch 38 can be routed outside the valve housing in the surrounding annular space. Depending on what choice is made there will be different considerations regarding how the system responds if a component fails, as will be explained below. The preferred embodiment is to run branch 38 to connection 40 along a route that has exposure to either tubing pressure or annulus pressure with annulus pressure preferred to assure desired failure modes in the event of leakage.
Pressure applied to the control line 10 goes through branch 38 to chamber 36 where it will exert an uphole force on lower piston 32 . Upper piston 30 has a seal 42 that is a larger diameter than seal 34 . Upper piston 30 has another seal 44 that is preferably the same or very close to the same size as seal 34 . Since both seals 44 and 34 are on the piston assembly 18 and are exposed on one side to the same tubing pressure, the piston assembly 18 experiences no net force from exposure to tubing pressure and can be referred to as tubing pressure insensitive for that reason. However, seal 42 is made larger than seal 34 by design and both are exposed to pressure in control line 10 and its branch 38 . While there is but a single control line 10 that runs from the surface that terminates at connections 40 and 46 , it can be seen that hydrostatic pressure in control line 10 is substantially offset by this arrangement. There is a net force from hydrostatic pressure in control line 10 on the piston assembly 18 in a downhole direction equal to the pressure near the connections 40 and 46 , which should be identical, divided by the area difference of seal 34 subtracted from the area of seal 42 . Of course, on application of pressure to control line 10 the net downhole force on piston assembly 18 increases to overcome the power spring 16 to shift the piston assembly 18 until shoulder 48 on the lower piston 32 engages shoulder 50 on flow tube 14 to rotate the flapper 12 to the open position.
In between seals 42 and 44 is a first variable volume chamber 52 that gets smaller as the piston assembly 18 is displaced against spring 16 . In order to allow the piston assembly 18 to move in that direction without getting bound, connection 54 has a line 56 leading to a reservoir 58 which is preferably at least 4 times the volume of chamber 52 . Line 56 continues to a valve 60 that is normally closed and whose purpose will be later explained. Beyond valve 60 line 56 ties into control line 10 . Reservoir 58 is preferably at atmospheric pressure or slightly higher and contains a compressible fluid. In normal operation, movement of the piston assembly 18 against spring 16 slightly raises the pressure in reservoir 58 to a degree related to the volume ratios between chamber 52 and reservoir 58 but in no way measurably impeding the movement of piston assembly 18 .
If there is a seal failure of seal 34 high tubing pressure can get into chamber 36 and from there through connection 40 and branch 38 to connection 46 and into chamber 62 . Since the pressure is now the same in third chamber 36 and second chamber 62 (i.e. tubing pressure)there would be a net opening force on piston assembly 18 due to the diameter of seal 42 being larger than the diameter of seal 34 (that has now failed). Without valve 60 in the system, the flapper 12 could be held open upon failure of seal 34 or, for that matter, failure of connections 40 and 46 . Valve 60 senses a pressure buildup in line 56 that occurs due to failure of seal 34 and tubing pressure migrating that far through branch 38 . Valve 60 can be a rupture disc or a piston held by a pin that shears or any other equivalent device that goes open at a predetermined pressure. When valve 60 opens the pressure at connections 46 and 54 equalizes removing any influence of tubing pressure on the piston assembly 18 that occurred due to failure of seal 34 . At that point the spring 16 pushes the piston assembly 18 to the valve closed position shown in FIG. 1 . From that point the piston assembly 18 can no longer be operated from control line 10 and flapper 12 is in its fail safe closed position.
Those skilled in the art will appreciate that the present invention illustrates a downhole tool control system that can run off a single control line from the surface 10 and that is further configured to address opposing ends of a piston assembly in a way that minimizes the effect of control line hydrostatic pressure. This reduction of the net effect of hydrostatic pressure despite use of a single control line to the surface allows the use of a lower pressure to move the piston assembly 18 . Differing diameters of the opposed ends of the piston assembly allow a sufficient net opening force to be applied to move the piston assembly 18 against the spring 16 . The piston assembly is insensitive to tubing pressure which dramatically lowers the required opening pressure as compared to conventional subsurface safety valves. The movement of the piston assembly 18 reduces the volume of a chamber 52 but with the addition of a reservoir of fairly large volume the resistance to movement from the compression effect of volume reduction in chamber 52 is made insignificant by the presence of large reservoir 58 which operates at an initial pressure that is close to atmospheric. With very high tubing pressures in the order of 20,000 PSI or more seals 44 and 34 see fairly large pressure differentials to help them seal more effectively. Failure of seal 34 , connection 40 , or connection 46 opens valve 60 to equalize pressure across seal 42 to let the spring 16 urge the flapper 12 to the fail safe closed position. Piston bores 24 and 26 may have a misalignment that can be compensated for by making the piston assembly 18 modular using a connector 28 that tolerates offset between the upper piston 30 and the lower piston 32 .
The above description is illustrative of the preferred embodiment and various alternatives and is not intended to embody the broadest scope of the invention, which is determined from the claims appended below, and properly given their full scope literally and equivalently. | A control system for a downhole tool, such as a subsurface safety valve, features an operating piston that is insensitive to tubing pressure in the valve. The hydrostatic forces from the single control line from the surface are significantly reduced with a branch line to a piston bottom that is slightly smaller than the piston top. A variable volume between piston seals is connected to a low pressure compressible fluid reservoir to permit piston movement. The piston can be modular to facilitate assembly or bore offsets in the valve body. Failsafe closure upon seal failures is contemplated. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the priority of Korean Patent Application No.-2006-57630, filed on Jun. 26, 2006, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
Aspects of the present invention relate to a file management system for a portable device, and more particularly, to a method and apparatus to manage a file that automatically creates a playlist in a portable device such as an mp3 player, a mobile phone or a game console.
2. Description of the Related Art
Generally, users need to view a playlist in order to use media in portable devices, such as mp3 players, mobile phones, or game consoles. In most portable devices, media that a user desires to play is managed using folders. However, since a file management method in portable devices utilizes a multimedia transfer protocol (MTP), the existing function of using folders is removed from the portable devices. Therefore, the conventional portable devices adopting the MTP need to additionally incorporate a playlist.
FIG. 1 is a flowchart of a method of creating a playlist in the conventional portable device. Referring to FIG. 1 , the portable device is first connected to a personal computer (PC) (operation 110 ). Second, the Windows Media Player 10 program is opened in the PC (operation 120 ). Then, a playlist is created using the Windows Media Player 10 program (operation 130 ). FIG. 2A shows an example of creating a playlist using the Windows Media Player 10 program.
Next, the playlist created using the Windows Media Player 10 program is synchronized with media in the portable device (operation 140 ). FIG. 2B shows an example of synchronizing files in the playlist with the media in the portable device using the Windows Media Player 10 program. Finally the portable device is disconnected from the PC (operation 150 ).
As described above, when using the conventional portable device, users are inconvenienced in having to create a playlist using a specific program, such as the Windows Media Player 10 program.
SUMMARY OF THE INVENTION
Aspects of the present invention provide a method and apparatus to automatically create a playlist, folder-by-folder.
According to an aspect of the present invention, there is provided a method of managing files of a portable device, the method comprising: copying files to be played from a source server and storing the files in a file system on a folder-by-folder basis; determining the presence of files which have been changed in the portable device by checking the file system when the files are completely copied; and creating a playlist of the files, folder-by-folder, according to file path information of the file system when there are added files.
According to another aspect of the present invention, there is provided an apparatus to manage files of a portable device, the apparatus comprising: a memory unit to store file information and playlist information on a folder-by-folder basis; an interface port unit to interface with a source server; and a control unit to copy files to be played on a folder-by-folder basis from the source server connected by the interface port unit, to store the files in a file system of the memory unit, to determine whether files which have been changed in the portable device are present with reference to a section of the file system where the files are stored, to analyze path information of the changed files, and to register the path information in the memory unit as a playlist on a folder-by-folder basis.
Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
FIG. 1 is a flowchart of a method of creating files in the conventional portable device;
FIG. 2A shows an example of creating a playlist using the Windows Media Player 10 program;
FIG. 2B shows an example of synchronizing files in a playlist with the media in a portable device using the Windows Media Player 10 program;
FIG. 3 is a block diagram of a portable device adopting a file management method according to an embodiment of the present invention;
FIG. 4 is a block diagram of a control unit illustrated in FIG. 3 ;
FIG. 5 is a flowchart of a method of managing files of a portable device according to an embodiment of the present invention;
FIGS. 6A and 6B are Windows screens explaining the file management method illustrated in FIG. 5 ;
FIG. 6C illustrates directories after a user copies files folder-by-folder; and
FIGS. 6D and 6E illustrate a file table and a playlist table map, respectively.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Reference will now be made in detail to the present embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures.
FIG. 3 is a block diagram of a portable device 300 adopting a file management method according to an embodiment of the present invention. First, the portable device 300 is connected to a personal computer (PC) 370 , and is disconnected from the PC 370 when a playlist is created. A user creates and/or stores desired music files, folder-by-folder, in the PC 370 , and the PC 370 acts as a source server to provide the files to the portable device 300 .
Referring to FIG. 3 , the portable device 300 includes a control unit 310 , a memory unit 320 , a display unit 330 , a user input unit 340 , a universal serial bus (USB) port unit 350 , and a digital-analog converter (DAC) unit 360 .
The memory unit 320 stores programs to control general operations of the portable device 300 and a program to control the automatic creation of a playlist according to an embodiment of the present invention, and temporarily stores data produced in the course of executing the programs. Specifically, the memory unit 320 includes a file table to store information on files in a unit of a folder, which has been copied from the PC 370 , and a playlist table to store file list information.
The user input unit 340 includes keys to allow the user to input numeral and character information, and functional keys to set various functions. However, it is understood that according to other aspects, the user input unit 340 includes other devices and methods to receive inputs from the user, such as a rotatable dial and/or a touch screen.
The display unit 330 displays user interface information output from the control unit 310 .
The DAC unit 360 converts audio data, which has been decoded in the control unit 310 , into analog audio signals and outputs the analog audio signals to speakers, earphones, and/or an external device.
The USB port 350 complies with the interface standard to connect the portable device 300 to the PC 370 . It is understood that according to other aspects, connection devices and methods other than USB are used, such as a Bluetooth unit to connect to the PC via a Bluetooth connection or an infrared unit to connect to the PC via an infrared connection.
The control unit 310 controls general operations of the portable device and/or decodes audio and/or video data stored in the memory 320 . Specifically, the control unit 310 copies files that are to be played, folder-by-folder, while connected to the PC 370 through the USB port 350 , determines if there are added or deleted files by checking a file system through, for example, a file allocation table (FAT) when the files are completely copied, and creates a playlist of the files copied folder-by-folder according to a change in the file system.
FIG. 4 is a block diagram of the control unit 310 illustrated in FIG. 3 . Referring to FIG. 4 , the control unit 310 includes a folder configuration unit 410 , a file detecting unit 420 , and a list creating unit 430 .
The folder configuration unit 410 copies the files that are to be played from the PC 370 through the USB port 350 , folder-by-folder, and stores the files in the file system corresponding to the FAT. According to an aspect, information on the files copied in the file system includes an index number, a file path, a physical memory start address, a file size, and table new/old information.
The file detecting unit 420 determines whether there are added or deleted files by checking for changes in the file system.
When the file detecting unit 420 determines that there is an added file, the list creating unit 430 analyzes path information of the file, creates a playlist title, and stores information on the added or deleted file (such as an index number, a file name, and a playlist title) in a playlist table.
FIG. 5 is a flowchart of a method of managing files of a portable device 300 according to an embodiment of the present invention. First, the portable device 300 is connected to a PC 370 (operation 510 ). The portable device 300 sets a check flag to 0 in a file system (operation 520 ). Then, the portable device 300 transmits a unique ID value to the PC 370 according to the media transport protocol (MTP) standard (operation 530 ). For example, if ID values of files used in the portable device 300 are 1, 2, 3, and 4, an ID value transferred to the PC 370 is 5. This ID value becomes the standard to set the index number of a file inside the PC 370 . For instance, the PC 370 sets indices of files as 5, 6, 7, and so on.
At the same time, a “portable device/media” folder is created in a screen of the PC 370 connected to the portable device 300 . The user creates folders including files that he or she desires to be played using a searching program on the PC 370 . Next, the user searches folders in the portable device 300 using the searching program, such as the Windows searching program illustrated in FIG. 6A . Then, the user copies the playlist folder-by-folder from the PC 370 to a media folder of the portable device 300 , as illustrated in FIG. 6B .
Afterwards, the portable device 300 checks if the files are copied to the portable device 300 using a write enable signal (operation 540 ). Then, the check flag is set by checking the file system (operation 542 ).
When the files are input from the PC 370 to the portable device 300 on a folder-by-folder basis, the files are copied to a buffer memory of the portable device 300 (operation 544 ). Referring to FIG. 6B , in the Windows screen, an “up-to-date-song” folder is copied to the media folder of the portable device. The directories illustrated in FIG. 6B can be displayed as a tree-like structure including folders and dependent files.
Then, the files are copied from the buffer memory to a storage unit in the portable device (operation 546 ). The storage unit may be, for example, NAND flash memory, NOR flash memory, or a hard disk drive.
The portable device 300 then stores information on the copied files in, for example, a FAT on a record-by-record basis (operation 548 ). FIG. 6D shows an example of the FAT storing the file information according to an embodiment of the present invention. An index number, a file path, a physical memory start address, a file size, a file name, and table new/old information of each file in the “up to date song” folder is stored in the FAT. For example, referring to FIGS. 6C and 6D , in the case of “1.mp3”, an index number is “1”, a file path is “root/media/up-to-date-song”, a physical memory start address is “20”, a file size is 20 bytes, and table new/old information is “new”. The table new/old information indicates if the file is registered from the file table to the playlist table.
When all files to be copied are completely copied, the portable device 300 confirms if the disconnection from the PC 370 is complete (operation 550 ). When confirming the disconnection from the PC 370 , the portable device 300 detects if there are added files which must be registered in the playlist table by checking the file system (operation 560 ). For example, when the check flag of the file system is set to 1, the portable device 300 determines that added files are present.
With reference to the table new/old information in the FAT, the portable device 300 counts the number of added files (operation 562 ). For example, if the number of files which have not been registered from the file table to the playlist table is five (that is, the number of files that have a table new/old information entry of “new”), the number of the added files is five. Then, file information of a first file, stored on a record-by-record basis in the FAT corresponding to the file system, is read (operation 572 ).
File path information of the first file is analyzed, and the last file directory or folder in the file path information of each record-by-record based file is registered in the table as a playlist title (operation 574 ). For example, the file path of a file (1.mp3) corresponding to an index number 1 is “root/media/up-to-date-song.” Therefore, the playlist title is “up-to-date-song,” which corresponds to the last folder in the file path. Then, the index number, the file name, and the playlist title of the file are stored in the playlist table, and a playlist table registering of the next added file is performed in the same manner (operation 576 ).
The operations 572 through 576 are repeated until the file number count becomes “0” (that is, all of the added files are registered in the playlist table). Finally, in the playlist table, file information is stored as illustrated in FIG. 6E . That is, referring to FIG. 6E , the playlist table includes an index number, a file name, and a playlist title of each file.
Aspects of the present invention can be written as computer programs and can be implemented in general-use digital computers that execute the programs using a computer-readable recording media. Examples of the computer-readable recording media include magnetic storage media (e.g., ROM, floppy disks, hard disks, etc.), optical recording media (e.g., CD-ROMs, or DVDs), and storage media such as a computer data signal embodied in a carrier wave including a compression source code segment and an encryption source code segment (e.g., transmission through the Internet). The computer-readable recording medium can also be distributed over network-coupled computer systems so that the computer-readable code is stored and executed in a distributed fashion.
According to an aspect of the present invention, a portable device 300 (such as an mp3 player or a mobile phone) creates a playlist automatically on a folder-by-folder basis without a user having to additionally create a playlist, thereby enabling the user to manage files conveniently.
Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents. | A method and apparatus to manage files of a portable device such as an mp3 player, a mobile phone, or a game console, the method comprising copying files to be played from a source server and storing the files in a file system on a folder-by-folder basis; determining the presence of files which have been changed in the portable device by checking the file system when the files are completely copied; and creating a playlist of the files, folder-by-folder, according to file path information of the file system when there are the changed files. | 6 |
BACKGROUND
[0001] Fall arrest systems that protect workers in the event of a fall are used in work locations where a fall could cause injury or death. A typical fall arrest system includes a safety harness that is donned by the worker, a lifeline that is attached to the harness, and a support structure in which the lifeline is connected. In some situations, such as in the construction of a new building, a suitable support structure to connect the lifeline to can be a challenge to find.
[0002] For the reasons stated above and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for an efficient and effective means to provide a support structure for a lifeline in a risk area that is void of adequate support structures.
SUMMARY OF INVENTION
[0003] The above-mentioned problems of current systems are addressed by embodiments of the present invention and will be understood by reading and studying the following specification. The following summary is made by way of example and not by way of limitation. It is merely provided to aid the reader in understanding some of the aspects of the invention.
[0004] In one embodiment, a parapet anchor is provided. The parapet anchor includes a frame, at least one adjustment member and a davit mount. The frame is configured and arranged to fit around a portion of a parapet. The at least one adjustment member is movably coupled to the frame to selectively engage the parapet to secure the frame to the parapet. Moreover, the davit mount is coupled to the frame and is configured arraigned to support a davit. The davit in turn can be used as a support structure to which a lifeline can be coupled.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The present invention can be more easily understood and further advantages and uses thereof more readily apparent, when considered in view of the detailed description and the following figures in which:
[0006] FIG. 1 is a side perspective view of an assembled parapet anchor of one embodiment of the present invention;
[0007] FIG. 2 is a side exploded perspective view of the parapet anchor of FIG. 1 ;
[0008] FIGS. 3 and 4 are a side views of the parapet anchor of FIG. 1 being positioned to engage a parapet;
[0009] FIGS. 5A and 5B are side views of select portions of the parapet anchor of FIG. 1 ;
[0010] FIG. 6 is a side view of the parapet anchor of FIG. 1 attached to a parapet;
[0011] FIG. 7A is a side view of the parapet anchor of FIG. 1 with a davit arm attached;
[0012] FIG. 7B is a side perspective view of a davit mount of one embodiment of the present invention;
[0013] FIG. 8 is a side view of the parapet anchor of FIG. 1 being removed from a parapet; and
[0014] FIG. 9 is a back side perspective view of a portion of the parapet anchor of FIG. 1 being prepared for transport or storage.
[0015] In accordance with common practice, the various described features are not drawn to scale but are drawn to emphasize specific features relevant to the present invention. Reference characters denote like elements throughout Figures and text.
DETAILED DESCRIPTION
[0016] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the inventions may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the spirit and scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the claims and equivalents thereof.
[0017] Embodiments of the present invention include parapet anchors that can be attached to a parapet. Embodiments of the parapet anchor can then be used as a stable support structure for the attachment of lifelines and the like. Hence, the parapet anchor can provide a stable support structure in a location where stable supports are typically not found such as, but not limited to, a construction location. A parapet anchor 100 of an embodiment is illustrated in FIGS. 1 and 2 . The parapet anchor 100 includes a lower assembly 202 and an upper assembly 204 as illustrated in FIG. 2 . When the lower assembly 202 is coupled to the upper assembly 204 , a generally C-shaped frame 101 is formed as illustrated in FIG. 1 . The frame 101 is coupled around a parapet as further described below.
[0018] The lower assembly 202 of the parapet anchor 100 includes a first lower member 102 a and a second lower member 102 b that are spaced apart by first and second lower frame spacers 104 a and 104 b. In particular, the first lower member 102 a includes a first end 170 a and a second end 170 b. The second lower member 102 b includes a first end 172 a and second end 172 b. The first lower frame spacer 104 a is positioned between the first lower member 102 a and the second lower member 102 b proximate the first end 170 a of the first lower member and proximate the first end 172 a of the second lower member 102 b. The second lower frame spacer 104 b is positioned proximate the second end 170 b of the first lower member 102 a and proximate the second end 172 b of the second lower member 102 b such that the first lower member 102 a is spaced in a parallel fashion from the second lower member 102 b by the first and second frame spacers 104 a and 104 b. In the embodiment illustrated in FIGS. 1 and 2 , the first lower member 102 a and the second lower member 102 b are respectively made from tubular members that are square in shape.
[0019] Each lower member 102 a and 102 b of the lower assembly 202 has a pair of lower engaging members 106 coupled thereto. Each engaging member 106 includes a bolt 106 a having an external threaded portion 106 c as illustrated in FIG. 2 . Bolt 106 a further includes an internal threaded bore 106 b. A washer 106 d is received around the bolt 106 a to abut a head of bolt 106 a. An engaging head 106 e threadably engages an internal threaded bore 106 b of the bolt 106 a. Bolt 106 a is then received through apertures in the respective lower members 102 a and 102 b such as aperture 103 a and 103 b illustrated in the second lower member 102 b in FIG. 2 . Spacers 106 f are received in the respective first and second lower members 102 a and 102 b to provide a passage and support for respective bolts 106 a of the engaging members 106 . A second washer 106 g is then received around the external threads 106 c of the bolt 106 a to abut a surface of the respective first or second lower members 102 a and 102 b. A nut 106 h then engages the external threads 106 c of the bolt 106 a to secure the respective engaging member 106 to the respective first and second lower members 102 a and 102 b. As illustrated, the engaging head 106 e extends above nut 106 h of the fastener 106 on each engaging member 106 . In one embodiment an engaging head 106 e is an engaging screw. The engaging head 106 e of each engaging member 106 can be replaced if they become worn.
[0020] The lower assembly 202 also includes a pair of lower support members 108 a and 108 b. In particular, the first lower support member 108 a extends generally perpendicular from the first lower member 102 a proximate the second end 170 b of the first lower member 102 a . The second lower support member 108 b extends generally perpendicular from the second lower member 102 b proximate the second end 172 b of the second lower member 102 b. In one embodiment the first and second lower support members 108 a and 108 b are tubular in shape. The first lower support member 108 a includes a pair of spaced passages 109 a and 107 a that extend generally in a perpendicular fashion, with respect to each other, through the first lower support member 108 a. Passages 109 a and 107 a are located proximate a terminal end of the first lower support member 108 a. Similarly the second lower support member 108 b includes a pair of perpendicular spaced passages 109 b and 107 b that are located proximate a terminal end of the second lower support member 108 b.
[0021] The upper assembly 204 of the parapet anchor 100 includes a first upper support member 110 a and a second support member 110 b. In the embodiment illustrated in FIGS. 1 and 2 , the first upper support member 110 a and the second upper support member 110 b are tubular in shape. Each of the first and second upper support members 110 a and 110 b have a diameter that is slightly larger than the diameter of the respective first and second lower support members 108 a and 108 b. The first lower support member 108 a is selectively received in the first upper support member 110 a and the second lower support member 108 b is selectively received in the second upper support member 110 b. Passages 111 in respective first and second upper support members 110 a and 110 b are aligned with respective passage 107 a and the first lower support member 108 a and passage 107 b in the second lower support member 108 b. Detent pins 122 are positioned in passages 111 in the first and second upper support members 110 a and 110 b and in passages 107 a of the first lower support member 108 a and the second passage 107 b in the second lower support member 108 b to selectively couple the upper assembly 204 to the lower assembly 202 .
[0022] The upper assembly 204 further includes a pair of upper members 114 a and 114 b that extend from the first upper support member 110 a and the second upper support member 110 b respectively. In particular, the first upper member 114 a extends generally perpendicular from the first upper support 110 a and the second upper member 114 b extends generally perpendicular to the second upper support member 110 b such that the parapet anchor 100 has a frame 101 that is generally C-shaped. The first upper member 114 a includes a first end 174 a and a second end 174 b. In one embodiment the first upper support 110 a passes through an opening in the first upper member 114 a proximate the second side 174 b of the first upper member 114 a. In this embodiment, a portion of the upper support member 110 a that includes passage 111 extends above the first upper member 114 a. The second upper member 114 b includes a first end 176 a and a second end 176 b. The upper support member 110 b in one embodiment passages through an opening in the second upper member 114 b proximate the second end of the second upper member 114 b. Likewise, a portion of the second upper support member 110 b extends above the second upper member 114 b such that passage 111 in the second upper support member 110 b is above the second upper member 114 b. In one embodiment, the first upper member 114 a and the second upper member 115 have a square tubular shape as illustrated in FIGS. 1 and 2 . When the upper assembly 204 is coupled to the lower assembly 202 , the first upper member 114 a runs parallel to and is aligned with the first lower member 102 a and the second upper member 114 b runs parallel to and is aligned with the second lower member 102 b in an embodiment.
[0023] A pair of upper spacers 118 a and 118 b coupled between the first and second upper members 114 a and 114 b provide spacing and support for the first and second upper members 114 a and 114 b. Each of the first and second upper members 114 a and 114 b has a pair of passages 115 . Adjusting member spacers 116 f are received in the respective first and second upper members 114 a and 114 b to further define passages 115 through the respective first and second upper members 114 a and 114 b. Adjustment members 116 are received in the respective passages 115 in the first and second upper members 114 a and 114 b. In particular, each adjustment member 116 includes a threaded shaft 116 a that is threadably engaged within a respective passage 115 through a respective first or second upper member 114 a or 114 b. Each adjustment member 116 further includes an adjustment handle 116 b that is coupled to a first end of the threaded shaft 116 a. A second end of the threaded shaft 116 a has a threaded bore that is designed to receive an engaging head 116 e. Engaging head 116 e is a screw in one embodiment. Further in one embodiment than each adjustment member 116 includes a cap portion 116 c that is coupled about the first end of the treaded shaft 116 a in which the handle portion 116 b is coupled.
[0024] The parapet anchor 100 further includes a handle 120 . Handle 120 includes an elongated member 120 a (grasping rod) that is coupled between a first tubular section 120 b (first connection flange) and a second tubular section 120 c (second connection flange). The first connection flange 120 b and second connection flange 120 c each have a diameter that is slightly larger than the diameter of the respective first lower support member 108 a and the second lower support member 108 b. Each of the first and second connection flange 120 b and 120 c having a passage 120 d passing there though. The respective passages 120 d through the first connection flange 120 b aligns with passage 109 a of the first lower support member 108 a and passage 120 d of the second connection flange 120 c aligns with passage 109 b of the second lower support member 108 b when the handle 120 is connected to frame 101 . In particular, a detent pin 121 is passed through passages 120 of the first connection flange 120 b and passage 109 a of the first lower support member 108 a. Likewise another detent pin 121 is passed through passage 120 d of the second connection flange 120 c and the end passage 109 b of the second lower support member 108 b thereby coupling the handle to the frame 101 of the parapet anchor 100 .
[0025] A davit mount 140 is coupled to the frame 101 . An illustration of davit mount 140 is illustrated in FIG. 7B . Davit mount 140 includes a tubular member 724 . Warning labels 726 regarding the use of the parapet anchor 100 can be placed on the tubular member 124 . Coupled proximate opposite ends of the tubular member 724 are davit mounting plates 138 a and 138 b and respective davit braces 720 . Apertures 720 pass though the respective davit mounting plates 138 a and 138 b and davit braces 720 . Apertures 720 are used to mount the davit mount 140 to first and second mounting members 112 a and 112 b of frame 101 as illustrated in FIG. 2 . The first and second mounting members 112 a and 112 b are mounted across surfaces of the first and second upper support members 110 a and 110 b. In particular, fasteners 142 (bolts in this embodiment) pass through apertures 720 in respective davit brackets 138 a and 138 b and through respective passages in the first mounting member 112 a and the second mounting member 112 b . The fasteners 142 further pass through support plate 124 a and 124 b that are positioned to abut the respective first mounting member 112 a and the second mounting member 112 b. Washer 148 and 149 are received on the respective fasteners 142 , 146 and nuts 128 threadably engage the respective fasteners 142 , 146 to couple the davit mount 142 to the frame 101 of the parapet anchor 100 . In one embodiment, a connector 144 which includes a base and a looped portion is mounted to the second mounting member 112 b via fastener 146 . The connector 144 provides a first anchor point to the parapet anchor 100 . A fastener 146 passes through a passage in the second mounting member 112 b and is coupled with a second mounting member 112 b by washers 148 , 149 and a nut 128 . In one embodiment the first upper member 114 a and the second upper member 114 b includes warning labels 150 on an outer surface. One embodiment further includes levels such as a first level 160 a coupled to the first upper member 114 a and a second level 160 b coupled to an upper support member such as the second upper support member 112 b . The levels 160 a and 160 b help insure the parapet anchor 100 is properly positioned when attached to a parapet.
[0026] Referring to FIGS. 3 and 4 , the positioning of the parapet anchor 100 on a structure 304 (a parapet) is illustrated. In one embodiment, a cable 302 (or strap) coupled to a hoist (not illustrated) is used to position the parapet anchor 100 into position relative to the parapet 304 . In particular, the cable 302 in one embodiment is coupled across upper spacers 118 a and 118 b of the parapet anchor 100 . The parapet anchor 100 , in one embodiment has a center of gravity that allows the parapet anchor 100 to be properly orientated to be received around the parapet 100 when cable 302 is coupled to the upper spacers 118 a and 118 b. The parapet anchor 100 is hoisted to a position that is within easy reach of an installer. In particular, the parapet anchor 100 is positioned so that the parapet 304 fits between the upper engaging heads 116 e of the adjustment members 116 and the lower engaging heads 106 e of the lower engaging members 106 as illustrated in FIG. 3 . As further illustrated in FIG. 3 , detents pins 122 are removed from passages 111 . This allows handle 120 to be lowered such that the respective first connection flange 120 b and second connection flange 120 c rests on respective ends of the first upper support member 110 a and the second upper support member 110 b. This provides extra space between the upper members 114 a and 114 b and the lower members 102 a and 102 b to ease in positioning of the parapet anchor 100 about the parapet 304 . The installer grasps the upper spacer 118 a to manipulate the parapet anchor 100 towards the installer to properly position the parapet 304 between C-shaped frame 101 of the parapet anchor 100 as illustrated in FIG. 4 .
[0027] Once, the parapet anchor 100 is properly positioned about the parapet 304 , handle 120 is grasped by the installer and pulled up as illustrated in the partial side-view of FIG. 5A . This action decreases the distance between the upper members 114 a and 114 b and the lower members 102 a and 102 b. Handle 120 is pulled up until passages 111 in the upper supper member 110 a and 110 b are aligned with passages 107 a and 107 b in the respective first and second lower support members 108 a and 108 b. Detent pins 122 are then passed through the aligned passages to couple the upper members 114 a and 114 b in a static position in relation to the lower members 102 a and 102 b. This is illustrated in the partial side view of FIG. 5B .
[0028] The parapet anchor 100 is then secured to the parapet 304 , as illustrated in FIG. 6 . In particular, adjustment handles 116 b of the adjusting members 116 are rotated to cause the upper engaging heads 116 e of the adjusting members 116 to engage a top surface of the parapet 304 and the lower engaging heads 106 e of engaging members 106 to engage a bottom surface of the parapet 304 . Hence, the parapet becomes sandwiched between the adjusting members 116 and the engaging members 106 . Levels 160 a and 160 b can be read by the installer to adjust the adjustment members 116 so that the parapet anchor 100 is properly leveled on the parapet 304 . Once the parapet anchor 100 is attached to the parapet 304 , the hoisting cable 302 (if used) can be removed. Referring to FIG. 7A a davit arm 700 is then inserted into davit mount 140 . The davit arm 700 can then be used as a stable support for life lines, and the like, attached to a safety harness of a user.
[0029] In removing the parapet anchor 100 from the parapet 304 , the davit arm 700 is first removed from the davit mount 140 . A hoist cable 302 can then be reconnected to the upper spacers 118 a and 118 b. The handles 116 b of the adjusting members then are rotated in an opposite direction they were rotated to engage the parapet 304 until a gap between the parapet 304 and the engaging members 106 is achieved. The parapet anchor 100 is then pushed away from the parapet 304 . Using a hoist and the hoist cable 302 the parapet anchor 100 is moved to the desired location. The hoist cable 302 is then removed. Once the parapet anchor 100 has been removed and positioned in a safe location it can then be prepared for reuse or storage. Referring to FIG. 9 , a partial back side perspective view of the parapet anchor 100 is provided. This view illustrates the parapet anchor 100 in a storage position. In this position, detent pins 122 are initially removed from passages 111 and 107 a and 107 b. This allows the upper support members 110 a and 110 b of the upper support assembly 204 of the parapet anchor 100 to slide down along the lower support members 108 a and 108 b of the lower assembly 202 until ends of the upper support members 110 a and 110 b rest on the first and second lower members 102 a and 102 b. The detent pins 122 can then be reinserted in passages 107 a and 107 b of the lower support members 108 a and 108 b for storage. FIG. 9 further illustrates that in one embodiment, a connector 902 that provides an anchor point to the parapet anchor 100 is coupled to the davit mount 140 .
[0030] Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement, which is calculated to achieve the same purpose, may be substituted for the specific embodiment shown. This application is intended to cover any adaptations or variations of the present invention. Therefore, it is manifestly intended that this invention be limited only by the claims and the equivalents thereof. | A parapet anchor is provided. The parapet anchor includes a frame, at least one adjustment member and a davit mount. The frame is configured and arranged to fit around a portion of a parapet. The at least one adjustment member is movably coupled to the frame to selectively engage the parapet to secure the frame to the parapet. Moreover, the davit mount is coupled to the frame and is configured and arranged to support a davit. The davit in turn can be used as a support structure upon which a lifeline can be coupled. | 4 |
BACKGROUND OF THE INVENTION
The invention generally relates to hydrostatic supporting devices, hydrostatic buttons, and in particular to hydrostatic buttons for supporting the axial thrust movement of a rotating collared shaft.
Hydrostatic buttons in various forms are already known and disclosed in U.S. Patent to: Christ et al U.S. Pat. No. 4,073,549, Engel et al U.S. Pat. No. 3,635,126, Van Gaasbet et al U.S. Pat. No. 3,799,628 and Spillman et al U.S. Pat. No. 3,802,044.
Hydrostatic buttoms comprise a top cylindrical head portion, having a bearing face operationally in supportive contact with a collared shaft bearing face, and a bottom cylindrical skirt portion. The skirt portion is provided with a circumferential groove, on its outer cylindrical surface, for receiving an elastomeric o-ring seal. The button is centrally bored along its symmetric axis and provided with an orifice therein. The button top cylindrical head portion includes a central circular recess, oriented coaxial with the button central bore, which is in fluid communication with the button central bore. Individual buttons are supported from a cooperating foundation in a cylindrical pocket therein, which pocket is fed pressurized fluid through a connecting passage in fluid communication with a pressurized fluid source. Typically a plurality of buttons are arranged in a circular array about the axis of the collared shaft. The o-ring seal prevents pressurized fluid from leaking from the pocket along the outer cylindrical surface of the skirt, thus creating a servomotor. The o-ring also provides some radial support for the button.
In operation, fluid pressure in the servomotor urges the hydrostatic button in the direction of the bearing face of the collared shaft. Pressurized fluid is bled through the button's orificed central bore to the central circular recess. Thus a hydrostatic bearing is formed capable of resisting thrust loading from a collard shaft bearing face tending to move the hydrostatic button toward the foundation pocket.
Since the collared shaft bearing face is rotating, there is some hydrodynamic bearing effect along with the hydrostatic bearing formed by the flow of pressurized fluid over the bearing face of the hydrostatic button. Rotation of the collar shaft tends to increase the flow of the pressurized fluid passing over the trailing edge of the hydrostatic button bearing face and results in a slight tip or tilt of the button.
While some tilting of the hydrostatic button is tolerable, the button must be constructed in a manner to avoid significant non-parallelism between the button bearing face and the bearing face of the shaft collar if this particular type of thrust compensation is to be effectively employed. The consequence encountered if significant non-parallelism occurs is gouges or nicks in the collared shaft bearing surface and eventual bearing failure.
To avoid significant non-parallelism some artisans have attempted to force balance the design of the hydrostatic button bearing face to avoid the adverse hydrodynamic bearing effects causing the tilting of the button. This approach results in very tight machining tolerances and significant expense, but is necessary due to the ineffectiveness of the o-ring to provide adequate radial support.
Furthermore the o-ring also tends to extrude into the circumferential groove as the button reciprocates causing a high and unconstant resistance to the button's travel.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to make an improved hydrostatic supporting device.
Another object of the present invention is to provide a hydrostatic supporting device that is relatively inexpensive to manufacture.
Yet another object of the invention is to provide a hydrostatic supporting device that avoids significant non-parallelism between the device and the member it supports.
A still further object of the present invention is to provide a more effective and efficient hydrostatic supporting device that allows for quite operation.
It is also an object of the present invention to provide a hydrostatic supporting device which offers only minimal and constant resistance to the button's travel.
A more complete appreciation of the invention and many of the attendant features thereof will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an axial sectional view of the hydrostatic supporting device of the invention supporting the collar of a rotating shaft.
FIG. 2 is an axial sectional view of another embodiment of the hydrostatic supporting device of the invention supporting the collar of a rotating shaft.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings wherein like reference characters designate identical or corresponding parts throughout the several views. FIG. 1 shows collared shaft 10 rotating in the direction of rotational arrow and moving back and forth axially, along its axis of rotation 11, due to shaft thrust loading. Collared shaft 10 is provided with a bearing face 12 oriented normal to the collared shaft axis of rotation 11.
Hydrostatic button 20 comprises a top cylindrical head portion 21 with bearing face 28 and a bottom multidiametered cylindrical skirt portion which is generally hour-glass in shape; that is the skirt has a large diameter section on top, a smaller diameter section in the middle and a large diameter section on the bottom, 22, 23 and 24 respectively. The large diameter section 24 is provided with a counter bore to receive small diameter section 23, which will operate as a male coupling. The small diameter section 23 receives bearing means 30 such as an annular elastomeric laminated bearing, as will be discussed more fully hereinafter. Hydrostatic button 20 is provided with a central bore 25 which is provided with an orifice 26. The top cylindrical head portion 21 includes a central circular recess 27, oriented coaxial with and normal to central bore 25, which is in fluid communication with central bore 25.
Hydrostatic button 20 is supported from a cooperating foundation 50 in cylindrical pocket 51 therein. Fluid seal means 40, such as an annular bellows prevents pressurized fluid from a pressurized fluid source, via a connecting passage 52, from leaking into pocket 51, thus creating a servomotor 42.
The servomotor 42 operation is conventional as generally is the hydrostatic and hydrodynamic operating characteristics of the hydrostatic button 20. However, now the bearing means and fluid seal means functions are provided by separate members. Bearing means 30 provides the function of support so as to prevent substantial non-parallelism of the button 20. Fluid seal means 40 provides the function of pressurized fluid sealing so as to create a servomotor.
Bearing means 30 comprises a series of laminated coaxial cylindrical rings that are alternatively metal and elastomeric in composition. The rings of bearing means 30 are bonded to one another. The inner diameter of the inner most ring of bearing means 30 corresponds to the outer diameter of the skirt section 23. The outer diameter of the outer most ring of bearing means 30 corresponds to the inner diameter of pocket 51 of foundation 50. Ideally both the inner most and outer most rings of bearing means 30 should be elastomeric so as to avoid the translation of vibration to the foundation 50. It is readily seen that bearing means 30 moves with button 20 as the button 20 reciprocates under the effect of thrust loading.
Bearing means 30 provides a large magnitude of radial support to the button 20, while at the same time providing minimal resistance to axial moment of button 20. The radial support of bearing means 30 is substantially constant when button 20 is vertical as when button 20 is tilted, due to hydrodynamic effects, because there is no substantial extrusion of the bearing means 30 as with a conventional o-ring experiencing hydrodynamic effects. Thence resistance to axial movement of button 20 is minimal and more constant.
Bearing means 30 is slipped over small diameter section 23 of the button 20 by removal of large diameter section 24. The large diameter section 22 of the button 20 will restrain bearing means 30 on its top side and by inserting the counter bore of section 24 on the male coupling of section 23 the bearing means 30 will be restrained on its bottom side. Sections 23 and 24 can be affixed by a press fit or by fastening means, such as, for example cap screws, which are threaded into the bottom of small diameter section 23. The hydrostatic button 20 is retained in cylindrical pocket 51 by retaining means 53, such as a metal ring affixed to foundation 50.
Fluid seal means 40, such as, for example, an annular bellows 40 is utilized to create a servomotor 42 between the button 20 and the pressurized pressure source. Fluid seal means 40 is generally of, a fluid tight, cylindrical shape and allowed to operate over a wide range of axial movements of button 20 by its bellows make up. The top of the annular bellows 40 is sealedly attached to, and coaxial with, the bottom of section 24 of the button 20. The bottom of the annular bellows 40 is sealedly attached to, and coaxial with, the bottom of pocket 51 via suitable means such as, for example, centrally bored ring 41 provided with a flanged end having equispaced bores to receive cap screws, which are threaded into the bottom of pocket 51. Ring 41 has an annular groove on its bottom surface to receive an o-ring seal. The bellows could be of a metallic material, in which case attachment could be by weld, or the bellows could be plastic.
FIG. 2 shows hydrostatic button 20A which comprises a top cylindrical head portion 21A with bearing face 28A and a multidiametered bottom cylindrical skirt portion having a large diameter section on top and a small diameter section on the bottom, 22A and 23A respectively. The small diameter section 23A receives a bearing means 30 such as the annular elastomeric bearing, supra. Hydrostatic button 20A is provided with a central bore 25A which is provided with an orifice 26A. The top cylindrical head portion 21A includes a central circular recess 27A oriented coaxial with and normal to central bore 25A, which is in fluid communication with central bore 25A.
Hydrostatic button 20A is supported from a cooperating foundation 50 in a cylindrical pocket 51A therein. Pocket 51A is fed pressurized fluid through a connecting passage 52 in fluid communication with a pressurized fluid source. Fluid seal means 45-49 such as of the rolling annular u-cup seal type prevents pressurized fluid leakage from the pocket 51A along the outer surface of the bottom cylindrical skirt sections 22A and 23A of hydrostatic button 20A, thus creating a servomotor 42A.
Annular u-cup seal 45-49 comprises two coaxial metal rings 45 and 46 each fixedly attached, i.e. by weld, to the inner circumferential surface of cylindrical pocket 51 and outer circumferential and hydrostatic button 20A respectively. Ring 45 is provided with a circumferential groove on its outer cylindrical surface to accommodate a fluid seal means 48 such as an o-ring. Ring 46 is provided with a circumferential groove on its inner cylindrical surface to accommodate a fluid seal 49 such as an o-ring. The two rings 45 and 46 are fluid sealedly connected by an annular U-cup seal 47, such as formed laminated steel welded to the rings 45 and 46 at its two extremities. The formed laminated steel is of sufficient length to allow for the reciprocal movement of hydrostatic button 20A. The u-cup seal 47 will essentially roll up and unroll as it allows for the hydrostatic button's 20A movement. The u-cup seal 47 offers sufficient flexibility and fatigue resisitance for small axial motions of approximately 11/8 of an inch.
The embodiment in FIG. 2 provides separate bearing means functions and fluid sealing means functions as was explained for in FIG. 1. Annular elastomeric bearing 30 still provides sufficient support to prevent substantial non-parallelism of the button 20A with respect to collared shaft bearing face 12. Bearing means 30 is slipped over small diameter section 23A of the button 20A. The large diameter section 22A of the button 20A will restrain bearing means 30 on its top side and by fixedly attaching metal ring 46 beneath bearing means 30, bearing means 30 will be restrained on its bottom side. The hydrostatic button is retained in pocket 51A by retaining member 53.
The second embodiment continues to allow for minimal resistance to axial movement of the button 20A due to the lack of extrusion of the bearing 30, as was experienced with a conventional o-ring bearing experiencing hydrodynamic effects.
Obviously, other embodiments and modifications of the present invention will readily come to those of ordinary skill in the art having the benefit of the teachings presented in the foregoing description and the drawings. It is therefore, to be understood that this invention is not limited thereto and that said modifications and embodiments are intended to be included within the scope of the appended claims. | A hydrostatic apparatus for supporting a collared shaft bearing face whichxially translates creating thrust force on a button bearing face wherein the button bearing is radially supported and fluidly sealed by two separate means. This arrangement avoids sustantial non-parallelism between said shaft bearing face and said button bearing face. | 5 |
RELATED APPLICATIONS
[0001] This application is a continuation-in-part of application Ser. No. 10/980,977 filed Nov. 4, 2004 that claims priority to and the benefit of provisional applications, Ser. No. 60/517,028 filed Nov. 4, 2003, Ser. No. 60/571, 977 filed May 18, 2004 and Ser. No. 60/599,673 filed Aug. 5, 2004.
BACKGROUND OF THE INVENTION
[0002] 1. Field Of The Invention
[0003] The present invention relates to the replacement of Refrigerant R-12 (dichlorodifluoromethane) with a blend refrigerant that is less damaging to the ozone layer in systems designed to use Refrigerant R-12 (dichlorodifluoromethane). More particularly, the present invention relates to an improved refrigerant composition, method and apparatus for refrigeration wherein two non-R-12 refrigerants are mixed in a defined ratio to balance the objectives of providing a temperature-pressure relationship of the mix approximating that of Refrigerant R-12 (dichlorodifluoromethane), while at the same time being less flammable than other replacement refrigerants, for HVAC, refrigeration and automotive applications. The mixture is compatible with Refrigerant R-12 (dichlorodifluoromethane) so that it can supplement and replace Refrigerant R-12 (dichlorodifluoromethane). A further particularity of the instant invention relates to an improved method and apparatus for refrigeration wherein refrigerant mixture is mixed with a lubricating oil compatible with the lubricating oil(s) placed in the equipment during manufacture or assembly.
[0004] 2. General Background
[0005] R-12 refrigerant dichlorodifluoromethane (hereinafter sometimes called “Refrigerant R-12 (dichlorodifluoromethane)”) was once the major, if not sole refrigerant, used in residential air-conditioners, refrigerators, freezers and automobiles. Refrigerant R-12 (dichlorodifluoromethane) is also known as Freon 12 a trademark of E. I. du Pont de Nemours & Co. Inc. for dichlorodifluoromethane. Hereinafter, “Refrigerant R-12 (dichlorodifluoromethane)” is used in this specification to denote dichlorodifluoromethane, regardless of the source.
[0006] Refrigerant R-12 (dichlorodifluoromethane) came under attack both nationally and internationally as an ozone layer-damaging chemical with a high global warming factor. Both the national and international scientific communities linked Refrigerant R-12 (dichlorodifluoromethane) with damage to the earth's protective ozone layer. Air-conditioners, refrigerator/freezers and auto units containing R-12 are believed to be a global source of ozone-damaging material and a direct cause of global warming.
[0007] In response to scientific concern and a national and global outcry over the use of Refrigerant R-12 (dichlorodifluoromethane) in air-conditioning and refrigeration, the United States Congress acted to first reduce and then ban the use of Refrigerant R-12 (dichlorodifluoromethane) in units.
[0008] Prior to banning the sale of quantities of Refrigerant R-12 (dichlorodifluoromethane), owners of equipment with Refrigerant R-12 (dichlorodifluoromethane)-based air-conditioning units were able to purchase the level of refrigerant in their equipment with only the need of a refrigerants license as required by the Clean Air Act. Millions of units containing refrigerant R-12 (dichlorodifluoromethane) were sold in the United States prior to the start of mandatory phase out set forth by Congress and the international community.
[0009] Refrigerant R-12 (dichlorodifluoromethane) recharging typically involves 30 lb. cans or cylinders used in the HVAC/R and auto industry. The cylinders are fitted with a dispensing outlet compatible with a commercially available refrigeration manifold. In order to recharge an air-conditioning system, a customer need to only fit the can or cylinder to the manifold and discharge, or “add to” the refrigerant charge directly into the air conditioning system.
[0010] Following Congress's limitations on the sale of Refrigerant R-12 (dichlorodifluoromethane) millions of equipment owners with Refrigerant R-12 (dichlorodifluoromethane)-based air-conditioning units were left with no choice other than to reclaim or seek replacement refrigerants to service these units. Intentionally mixing of refrigerants is currently illegal by standards set forth by the Clean Air Act.
[0011] In response to Congress's ban on the use of Refrigerant R-12 (dichlorodifluoromethane) in air-conditioning, service dealers retrofitted existing Refrigerant R-12 (dichlorodifluoromethane)-based air-conditioning units with new, non-R-12 refrigerants.
[0012] Other refrigerants were developed to replace the prior, now banned R-12 refrigerant, or dichlorodifluoromethane. For example, Tamura et al. (U.S. Pat. No. 4,983,312) discloses a refrigerant consisting essentially of R134a (1,1,1,2-tetrafluoroethane) and R142b (chlorodifluoroethane). Tamura et al., however, makes no teaching or suggestion of a lubricant.
[0013] Wilczek (U.S. Pat. No. 5,384,057), Gorski (U.S. Pat. No. 4,971,712), and Anton of DuPont (U.S. Pat. No. 5,145,594) disclose other R-12 replacements in the form of a blend of certain synthetic lubricants in various R134a and R134a/R125 refrigerant systems. The DuPont patents discuss a gas known as R125 (pentafluoroethane). R125 is five fluorine atoms bonded to an ethane molecule. This is a very large molecule for a refrigerant. It is currently being produced for refrigeration only. Anton discloses the use of a lubricant comprising at least one cyanocarbon compound. Wilczek discloses a fluorosiloxane as a lubricant. Gorski discloses a polyakylene glycol as a lubricant.
[0014] Begeman, et al. (U.S. Pat. No. 3,092,981) disclose the use of a fluoro halo derivative of an aliphatic hydrocarbon as a refrigerant in combination with alkylbenzene of 1 to 50 carbons and a viscosity of 50 to 2000 SUS (Saybolt Universal Seconds) at 100° F. Olund (U.S. Pat. No. 3,642,634) discloses a lubricating oil for refrigeration equipment consisting essentially of a high viscosity alkylbenzene having a viscosity in the range of 3000 to 1,000,000 SUS at 100° F. and a refrigerant containing a halongenated alkyl working fluid and this high viscosity alkylbenzene. (U.S. Pat. No. 3,733,850 and U.S. Pat No. 4,046,533). Kaneko (U.S. Pat. No. 5,520,833) discloses the use of a lower viscosity (viscosity of 2 to 50 cst at 100° C.) alkylbenzene or alkylnapthelene with a substitute flon compound as a refrigerant. Generally, synthetic oils, such as alkylbenzene, and mineral oils have not been used in conjunction with R134a (1,1,1,2-tetrafluoroethane). As noted by Fukuda, et al (U.S. Pat. No. 5,417,872) R134a has unique properties due to its special chemical structure, so that it is not miscible in refrigerating machine oils used in the refrigeration systems of R-12 refrigerant, e.g. mineral oils (naphthenic oils, paraffinic oils) and synthetic oils such as alkylbenzene.
[0015] Systems that contain R-12 are still in use today. These older systems have common components: R-12, R-12 mineral oil lubricant, and water that is sequestered into the dryer. If R134a (1,1,1,2-tetrafluroethane) were added to the system, it would damage the system as follows: (1) if no lubricant is added to the R134a (as in U.S. Pat. No. 4,953,312 to Tamura et al.), then the R-12 system would be starved for lubricant, since the R134a gas is not miscible with the mineral oil lubricant; (2) if a synthetic lubricant is added to the R134a (as in Thomas et al., U.S. Pat. No. 5,254,280), then there is a different problem—that of moisture. Older systems can have water trapped in their dryers. Synthetic lubricants such as polyglycol or polysiloxane-based lubricants are hydrophilic. They are not only miscible with R-12 and R134a; they are also partially or completely miscible with water. Thus, if they are introduced into an R-12 system, they will pull this water out of the dryer into the refrigerant flow, possibly initiating corrosion and damage to pressure switches and the TX valve and possible other system components. This is why Elf Atochem and DuPont, to name a few publish elaborate flushing procedures and high efficiency dryer change-outs to prevent damage to the cooling system.
[0016] Weber (U.S. Pat. No. 5,492,643, U.S. Pat. No. 5,942,149, and U.S. Pat. No. 6,565,766) discloses yet another R-12 replacement consisting of a blend of R-142b (chlorodifluoroethane) in the amount of about 15% to about 40%, R-134a (tetrafluoroethane) in the amount of about 60% to about 85%, and a napthenic lubricating oil (Royco 783C, 783D). Weber generally teaches away from use of synthetic lubricants for the reasons mentioned above. Weber also teaches away from use of higher amounts of R-134a (tetrafluoroethane) noting that at higher temperature ranges, the pressure of R-134a in pure form is well above that of Freon 12 so that it would pose a hazard if used in equipment designed for using Freon 12. Further, Weber's replacement has the disadvantage of being relatively flammable because of its aerosoling tendency. In the Weber patents the preferred composition contains 79% R134a (tetrafluoroethane), 19% R142b (chlorodifluoroethane) and 2% (lubricant, Royco 783C or 783D) blend that is recognized by Refleak and Refprop (accepted industry computer modeling programs for fractionation analysis) to be flammable in the worst case formulation (WCF) temperature ranges of refrigeration uses as described in ASHRAE Standard 34 and accepted in industry. Proprietary computer modeling and bench top testing from DuPont and Honeywell also show flammability problems and concerns during worst-case fractionation (WCF) preventing acceptance in refrigeration applications. Thus, the American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. (ASHRAE) has been unwilling to grant a designation for Weber's refrigerant blend, in particular his preferred blend of 79%/19% and 2% lubricant. The focus of Weber's patents is directed to automobile applications, an industry that monitors less closely than the HVAC/R industry.
[0017] Thus, there exists a need for an R-12 refrigerant replacement having reduced flammability which meets ASHRAE's requirements for designation while at the same time providing lubrication.
SUMMARY OF THE PRESENT INVENTION
[0018] The present disclosure provides a method and apparatus that are environmentally sound alternatives to the use of Refrigerant R-12 (dichlorodifluoromethane) as a refrigerant. More particularly, the disclosure herein provides a mixture of at least two refrigerants that are miscible with each other, and compatible with Refrigerant R-12 (dichlorodifluoromethane) and its equipment while at the same time providing a good compromise between temperature-pressure profile with similar thermodynamic properties that approximates that of Refrigerant R-12 (dichlorodifluoromethane) over the operating range of ambient temperatures usually encountered by air conditioning and refrigeration units or other apparatus utilizing Refrigerant R-12 (dichlorodifluoromethane) as a refrigerant and while at the same time reducing the flammability of the mixture to levels acceptable to ASHRAE Standard 34 and UL2182 among others. In fact in August of 2003 an exemplary embodiment of the present disclosure received an ASHRAE designation of R420A rated A1 in its safety classification. The present disclosure also provides a lubricant, that is compatible with the mixture of the environmentally sound refrigerants described herein and with Refrigerant R-12 (dichlorodifluoromethane), so that mixtures of the refrigerant according to the invention and Refrigerant R-12 (dichlorodifluoromethane) may be utilized with this lubricant in the refrigeration systems without deleterious effect upon moving parts of the refrigerating apparatus that require lubrication from the refrigerant.
[0019] More particularly, the present disclosure provides a mixture of chlorodifluoroethane and tetrafluoroethane in specific proportions that provide the aforesaid compromise over the range of ambient temperature operating conditions in which Refrigerant R-12 (dichlorodifluoromethane) is a useful refrigerant. For example, the tetrafluoroethane can include either 1,1,1,2-tetafluoroethane (R-134a) or 1,1,2,2-tetrafluoroethane (R134) and the chlorodifluoroethane can include either 1-chloro-1,1-difluoroethane (R142b) or 2-chloro-1, 1-difluoroethane. In an exemplary embodiment, the refrigerant according to the invention comprises a ratio of from about 5% to about 40% weight percent chlorodifluoroethane and from about 60% to about 95% tetrafluoroethane, based upon the combined weight of tetrafluoroethane and chlorodifluoroethane. In another exemplary embodiment, the refrigerant according to the invention comprises a ratio of from less than 13% to above 10% weight percent chlorodifluoroethane and to above 87% to less than 90% tetrafluoroethane, based upon the combined weight of tetrafluoroethane and chlorodifluoroethane. In a further exemplary embodiment, the refrigerant includes 12.0%-11.0% by weight chlorodifluoroethane and 88.0%-89.0% by weight tetrafluoroethane. In yet a further exemplary embodiment, the refrigerant includes the ratio of about 12 weight percent chlorodifluoroethane to about 88 weight percent tetrafluoroethane.
[0020] In addition, the refrigerant includes a lubricating oil that is soluble in the mixture of the chlorodifluoroethane and tetrafluoroethane. In an exemplary embodiment, the percentage by weight of lubricant in the refrigerant mixture is from about 0.5 to about 20 weight percent (based on the combined weight of chlorodifluoroethane and tetrafluoroethane), more preferably 1-2%, even more preferably 1.25-2%, and most preferably 1.5-1.75% (based on the combined weight of chlorodifluoroethane and tetrafluoroethane). In another exemplary embodiment about 0.5% to about 2% by weight of the refrigerant is a hydrophobic naphthenic lubricating oil that is miscible with the cholordifluoroethane and tetrafluorethane.
[0021] Suitable lubricants are hydrophobic (immiscible with water) lubricants. Preferably no more than 5% by weight of the lubricant is hydrophilic lubricant (some aliphatic hydrocarbon solvents can absorb up to 5% by weight water and still maintain lubricating integrity). More preferably, no more than 2% by weight of the lubricant is hydrophilic lubricant. Most preferably, the refrigerant blend contains no hydrophilic lubricant.
[0022] In an exemplary embodiment, the lubricant is a man-made, synthetic alkyl aromatic lubricant. Suitable synthetic lubricants include alkylated benzene lubricants. The lubricant can be either alkylbenzene alone or a mixture of alkylbenzene and mineral oil or a mixture of alkylbenzene and polyol ester (POE).
[0023] In a further exemplary embodiment, the lubricant can be a naphthenic or a paraffinic based lubricating oil that is soluble in dichlorodifluoromethane, chlorodifluoroethane, and tetrafluoroethane, or mixtures thereof. For example, the lubricant can be selected from those lubricants sold by Anderol, Inc., East Hanover, N.J., an affiliate of Royal Lubricants Company, under the trademark ROYCO® 2302. It should be understood, however, that other lubricating oils might also be used, as long as they are compatible with chlorodifluoroethane, tetrafluoroethane, and Refrigerant R-12 (dichlorodifluoromethane) and hydrophobic.
[0024] ROYCO® 2302 is a naphthenic oil lubricant having the following composition:
[0025] 65-85% hydrotreated light naphthenic distillate,
[0026] 10-20% solvent refined light naphthenic distillate petroleum,
[0027] <0.5% butylated triphenyl phosphate, and
[0028] <2% minor additive.
[0029] The ROYCO® 2302 lacks the barium dinonylnapthalene sulfonate additive of Royco 783C and 783D.
[0030] Various additives can be included in the lubricant. Examples include a corrosion inhibitor, such as for anhydrous systems, and/or a surfactant or foaming agent. Phosphated additives add corrosion resistance in the presence of acids and salts and increase wear resistance. Calcium additives help the lubricant resist rust and the effects of corrosion; calcium salts reduce the corrosive effects of hydrochloric acid that is formed in the presence of water and the chlorinated gases present in the refrigerant systems of the present invention.
[0031] The ROYCO® 2302 lubricant mentioned above contains the corrosion inhibitors mentioned above and can also contain acrylic polymer. It is believed that the function of the acrylic polymer is to increase wear resistance under severe conditions. Acrylics can help film formation, and the ability of the lubricant to coat metal and soft parts and stay in place.
[0032] While it is intended that the substitute refrigerant according to the present disclosure may be utilized to replace or as a substitute for Refrigerant R-12 (dichlorodifluoromethane) that has escaped from apparatus, the substitute refrigerant of the invention may also be utilized to completely refill apparatus that have been designed for use with Refrigerant R-12 (dichlorodifluoromethane), since the refrigerant has a temperature-pressure profile close enough to that of Refrigerant R-12 (dichlorodifluoromethane), particularly for HVAC and refrigeration (HVAC/R) applications. Thus, when the refrigerant is used as a complete replacement for Refrigerant R-12 (dichlorodifluoromethane), it is no longer necessary that the lubricant be compatible with dichlorodifluoromethane but only that it should be compatible with tetrafluoroethane and chlorodifluoroethane and the lubricants typically used in R-12 systems. In another embodiment of the present disclosure, the refrigerant can be used as the original refrigerant in the apparatus.
[0033] In further specifics, the present disclosure provides a canister, such as an aerosol can, containing a mixture of tetrafluoroethane and chlorodifluoroethane with a synthetic lubricating oil that may be fitted with an outlet manifold that is compatible with a Refrigerant R-12 (dichlorodifluoromethane) recharging manifold that is typically used to recharge an apparatus with the latter refrigerant. Refrigerant may then be allowed to flow from the container through the manifold and into the apparatus to replace Refrigerant R-12 (dichlorodifluoromethane) refrigerant that has been lost from the refrigeration system. Significantly, there is no need to flush an existing system to use the refrigerant with the lubricant of the present disclosure.
[0034] When mixing the components of the refrigerant blend of the present disclosure, one should first mix the lubricant with the chlorodifluoroethane, then mix that mixture with the tetrafluoroethane in the proportions afore mentioned. Otherwise, the product may not mix properly. When adding the refrigerant blend of this disclosure to a refrigerant system, one should leave the greatest amount of lubricant in the system if one for some reason takes out the Refrigerant R-12.
[0035] The present disclosure is designed to be utilized as a R-12 replacement in refrigeration systems. It is designed as a replacement, in which little or no modifications including parts are used to adapt the system for the refrigerant of the present disclosure.
[0036] The lubricants of the present disclosure are miscible with the chlorodifluoroethane and tetrafluoroethane refrigerant blend and with R-12 refrigerant. This allows for mixing of residual R-12 refrigerant and the refrigerant of the present disclosure, without the release of residual water in the dryer and subsequent system damage (as will happen if the synthetic lubricants disclosed in Thomas et al. and the DuPont patents are used).
[0037] The present refrigerant mixture can be used as a replacement for R-12 refrigerant, typically deminimus without retrofitting the air conditioning system or flushing it out. It is recommended that a full vacuum be obtained before adding the refrigerant.
BRIEF DESCRIPTION OF THE FIGURES
[0038] The present refrigerant will hereinafter be described and more readily understood from a reading of the following description and by reference to the accompanying drawings.
[0039] FIG. 1 is a graph comparing the temperature-pressure profiles of various R-142/R-134a blends versus the profile for R-12.
[0040] FIG. 2 is a graph of a fractionation analysis on various R-142/R-134a blends.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0041] The present refrigerant is a mixture of non-Refrigerant R-12 refrigerants that are less damaging to the Earth's ozone layer with a lower global warming factor and that are recommended by the U.S. Environmental Protection Agency for use in HVAC/R and also by ASHRAE. The refrigerant mixture is compatible with Refrigerant R-12 (dichlorodifluoromethane) and can be used to replace existing Refrigerant R-12 (dichlorodifluoromethane) in existing R-12 based systems. The present refrigerant replaces Refrigerant R-12 (dichlorodifluoromethane) in Refrigerant R-12 (dichlorodifluoromethane) based air-cooling and refrigeration systems, without the need to retrofit existing Refrigerant R-12 (dichlorodifluoromethane) based systems for non-Refrigerant R-12 replacement refrigerants and without the need to flush the system.
[0042] Specifically, the present refrigerant includes a mixture of chlorodifluoroethane and tetrafluoroethane and a lubricant provided under pressure in a can or cylinder equipped with an outlet compatible with existing Refrigerant R-12 (dichlorodifluoromethane) recharging kit manifolds, so that the refrigerant and lubricant mixture can be added to existing Refrigerant R-12 (dichlorodifluoromethane) based coolant systems. Also, the present refrigerant provides the possibility of using new refrigerant systems, originally designed for “Refrigerant R-12 (dichlorodifluoromethane),” by supplying an EPA-approved refrigerant so that retrofitting to new equipment use is not required.
[0043] In an exemplary embodiment, a cylinder can like the standard 25 or 30 lb. can formerly used for containing Refrigerant R-12 (dichlorodifluoromethane) is provided, but containing from about 60% to about 95% by weight tetrafluorethane (R-134 refrigerant) and from about 5% to about 40% by weight chlorodifluoroethane (R-142 refrigerant). The can also contains a lubricant in solution with the refrigerant mixture at a percent by weight of in the range of about 0.5% up to about 20% by weight of the combined weight of the refrigerants.
[0044] In another exemplary embodiment, a cylinder can like the standard 25 or 30 lb. can formerly used for containing Refrigerant R-12 (dichlorodifluoromethane) is provided, but containing less than 90% to more than 87% by weight tetrafluorethane (R-134 refrigerant) and more than 10% to less than 13% by weight chlorodifluoroethane (R-142 refrigerant). The can also contains a lubricant in solution with the refrigerant mixture at a percent by weight of in the range of about 0.5% up to about 2% by weight of the combined weight of the refrigerants.
[0045] Such lubricants are preferably hydrophobic (immiscible with water) lubricants. Preferably no more than 5% by weight of the lubricant is hydrophilic lubricant (some aliphatic hydrocarbon solvents can absorb up to 5% by weight water and still maintain lubricating integrity). More preferably, no more than 2% by weight of the lubricant is hydrophilic lubricant. Most preferably, the refrigerant blend contains no hydrophilic lubricant.
[0046] One exemplary lubricant is the aforementioned Royco 2302 naphthenic lubricant. The lubricant can have a viscosity of 5-500 centistokes. In another embodiment the lubricant can has a viscosity of 5-10 centistokes.
[0047] Another exemplary lubricant is a synthetic alkylate hydrocarbon, such as a man-made, synthetic alkyl aromatic lubricant. One example of such a lubricant is a synthetic alkylbenzene sold under the product name Zerol 30 by Shrieve Chemical products. Zerol 30 is an extra low viscosity, high quality, synthetic alkylbenzene composition having a boiling point of greater than 240° C. at atmospheric pressure, a specific gravity at 15° C. of 0.86-0.88, a viscosity of 4-8 cSt at 40° C. (typically about 5.5 cSt), a pour point of −35° C. max (typically −40° C.), and a water content of 30 ppm in bulk. Such a synthetic alkylate hydrocarbon lubricant can also include a minor portion of either mineral oil or polyol ester (POE) mixed with the synthetic lubricant. By minor portion we mean less than 50% by weight of the total lubricant present.
[0048] The present disclosure provides lubricants that are compatible with the invention mixture of tetrafluoroethane and chlorodifluoroethane, and with “Refrigerant R-12 (dichlorodifluoromethane),” and that are suitable for lubricating refrigerant compressors and other air-conditioner component parts. While alkylbenzene alone is considered not miscible with tetrafluoroethane (in particular R134a), it is sufficiently soluble in the present tetrafluoroethane/chlorodifluoroethane mixture. This solubility allows the replacement refrigerant blend to lubricate the system, preventing damage to the compressor and component parts of the system.
EXAMPLE 1
[0049] 1,1,1,2-tetrafluoroethane and dichlorofluoroethane refrigerants are mixed with a suitable lubricant, such as either the Royco 2302 naphthenic lubricant or an alyklbenzene synthetic lubricant (such as L30 or L35 from Shrieve Chemical Company, The Woodlands, Texas, or Zerol 150 from Nu-Calgon Wholesale, Inc., St. Louis, Mo., or AB 150 from Virginia KMP Corporation, Dallas, Tex.) at set ratios such that the temperature-pressure profile of the mixture is compared to that of Refrigerant R-12 (dichlorodifluoromethane), over the normal operating range of air conditioning and refrigeration systems of from about −60° F. to 160° F. The set ratios range from 80% to 90% 1,1,1,2-tetrafluoroethane and 10% to 20% chlorodifluoroethane. A similar temperature-pressure profile was obtained for Refrigerant R-12 (dichlorodifluoromethane). The results were plotted and compared in FIG. 1 . FIG. 1 shows that as the amount of tetrafluoroethane increases in the blends, the temperature-pressure profile of the blends has a greater divergence from the temperature-pressure profile of R-12 at the higher temperatures.
[0050] A fractionation analysis was conducted for three of the blends found in FIG. 1 , namely blends having ratios of 86/14, 88/12 and 90/10 by weight percent of tetrafluoroethane to chlorodifluroethane. The results of this fractionation analysis are illustrated in FIG. 2 . The purpose of this test is to determine the effect on the refrigerant mixture should a leak occur in the refrigeration or air conditioning system. The lubricant used has no effect on this analysis. Since tetrafluoroethane evaporates at lower temperatures than chlorodifluroethane, when a leak occurs more tetrafluoroethane evaporates than chlorodifluoroethane. Thus, for example, for an 86/14 blend of tetrafluoroethane to chlorodifluoroethane when 95% of the initial mass of blend has leaked, the remaining liquid refrigerant comprises 52.91% R142b (chlorodifluroethane). A liquid refrigerant having that much R142b (chlorodifluroethane) is considered flammable. In general, the refrigerant mixture needs to have less than about 48% R142b in the liquid to be considered to have a reduced level of flammability acceptable to ASHRAE Standard 34 and to receive an ASHRAE designation rated A1 in its safety classification.
[0051] The most preferred ratio is about 12% by weight chlorodifluoroethane to about 88% by weight 1,1,1,2-tetrafluoroethane. This is the ratio of chlorodifluoroethane to 1,1,1,2-tetrafluoroethane with the lubricant where the mixture of the invention shows the best compromise between greatest similarity to “Refrigerant R-12 (dichlorodifluoromethane)” over most operating temperatures with no flame propagation. At this ratio, the fractionation study of FIG. 2 shows a residual concentration of R-142 (chlorodifluoroethane) at 95% mass leaked of 47.3%, just below the concentration of R-142 considered to be flammable.
[0052] In the most preferred embodiment of the composition, the most preferred ratios of 1,1,1,2-tetrafluoroethane and chlorodifluoroethane are mixed with a range of from 0.5% to 2% by weight of lubricant as aforementioned.
[0053] A pressure temperature comparison of 12% chlorodifluorethane to 88% tetrafluoroethane to R-12 and R-134a is provided below in Table 1.
TABLE 1 Choice-R420A ° F. Refrigerant R-12 HFC-134a −40 17.8* 11.0 14.8 −35 15.0* 8.4 12.5 −30 12.1* 5.5 9.8 −25 9.0* 2.3 6.9 −20 5.8* 0.6 3.7 −15 2.2* 2.4 0.0 −10 0.7 4.5 1.9 −5 2.7 6.7 4.1 0 4.9 9.2 6.5 5 7.3 11.8 9.1 10 9.9 14.6 12.0 15 12.8 17.7 15.0 20 15.8 21.0 18.4 25 19.2 24.6 22.1 30 22.8 28.5 26.1 35 26.6 32.6 30.4 40 30.8 37.0 35.0 45 35.4 41.7 40.0 50 40.2 46.7 45.3 55 45.5 52.0 51.0 60 51.0 57.7 56.4 65 57.0 63.8 63.7 70 63.4 70.2 70.7 75 70.2 77.0 78.5 80 77.4 84.2 86.4 85 85.1 91.8 95.3 90 93.3 99.8 104.2 95 102.0 108.3 114.1 100 111.1 117.2 124.3 105 120.8 126.6 135.4 110 131.1 136.4 146.8 115 141.9 146.8 159.2 120 153.2 157.7 171.9 125 165.2 169.1 185.7 130 177.7 181.0 199.8 135 190.9 193.5 215.0 140 204.7 206.6 230.5 145 219.2 220.3 247.3 150 234.3 234.6 264.4 (*= in.Hg vacuum)
EXAMPLE 2
[0054] A temperature glide example of a mixture of 12% chlorodifluoroethane and 88% afluoroethane refrigerants was conducted at a temperature of 80° F. The exemplary mixture had a temperature glide of 2.5° F. as compared to 4° F. for R-12. The resulting temperature glide chart is in Table 2 below.
TABLE 2 Temp P Bubble P Dew (° F.) (psia) (psia) −40 6.941 6.641 −39 7.165 6.855 −38 7.389 7.069 −37 7.613 7.283 −36 7.837 7.497 −35 8.061 7.711 −34 8.285 7.925 −33 8.509 8.139 −32 8.733 8.353 −31 8.957 8.567 −30 9.181 8.781 −29 9.460 9.048 −28 9.739 9.315 −27 10.018 9.582 −26 10.297 9.849 −25 10.576 10.116 −24 10.855 10.383 −23 11.134 10.650 −22 11.413 10.917 −21 11.692 11.184 −20 11.971 11.451 −19 12.314 11.779 −18 12.657 12.107 −17 13.000 12.435 −16 13.343 12.763 −15 13.686 13.091 −14 14.029 13.419 −13 14.372 13.747 −12 14.715 14.075 −11 15.058 14.403 −10 15.401 14.731 −09 15.817 15.130 −08 16.233 15.529 −07 16.643 15.928 −06 17.059 16.327 −05 17.475 16.726 −04 17.891 17.125 −03 18.307 17.524 −02 18.723 17.923 −01 19.139 18.322 0.0 19.555 18.721 1.0 20.056 19.201 7.0 23.062 22.081 8.0 23.563 22.561 9.0 24.064 23.041 10.0 24.565 23.521 11.0 25.161 24.093 12.0 25.757 24.665 13.0 26.353 25.237 14.0 26.949 25.809 15.0 27.545 26.381 16.0 28.141 26.953 17.0 28.737 27.525 18.0 29.333 28.097 19.0 29.929 28.669 20.0 30.525 29.241 21.0 31.229 29.916 22.0 31.933 30.591 23.0 32.637 31.266 24.0 33.341 31.941 25.0 34.045 32.616 26.0 34.749 33.291 27.0 35.453 33.966 28.0 36.157 34.641 29.0 36.861 35.316 30.0 37.565 35.991 31.0 38.389 36.782 32.0 39.213 37.573 33.0 40.037 38.364 34.0 40.861 39.155 35.0 41.685 39.946 36.0 42.509 40.737 37.0 43.333 41.528 38.0 44.157 42.319 39.0 44.981 43.110 40.0 45.805 43.901 41.0 46.762 44.822 42.0 47.719 45.743 43.0 48.676 46.664 44.0 49.633 47.585 45.0 50.590 48.506 46.0 51.547 49.427 47.0 52.504 50.348 48.0 53.461 51.269 54.0 59.791 57.367 55.0 60.895 58.431 56.0 61.999 59.495 57.0 63.103 60.559 58.0 64.207 61.623 59.0 65.311 62.087 60.0 66.415 63.751 61.0 67.680 64.972 62.0 68.945 66.193 63.0 70.210 67.414 64.0 71.475 68.635 65.0 72.740 69.856 66.0 74.005 71.077 67.0 75.270 72.298 68.0 76.535 73.519 69.0 77.800 74.740 70.0 79.065 75.961 71.0 80.506 77.354 72.0 81.947 78.747 73.0 83.388 80.140 74.0 84.829 81.533 75.0 86.270 82.926 76.0 87.711 84.319 77.0 89.152 85.712 78.0 90.593 87.105 79.0 92.034 88.498 80.0 93.475 89.891 81.0 95.108 91.472 82.0 96.741 93.053 83.0 98.374 94.634 84.0 100.007 96.215 85.0 101.640 97.796 86.0 103.273 99.377 87.0 104.906 100.958 88.0 106.539 102.539 89.0 108.172 104.120 90.0 109.805 105.701 91.0 111.645 107.487 92.0 113.485 109.273 93.0 115.325 111.059 94.0 117.165 112.845 95.0 119.005 114.631 2.0 20.557 19.681 3.0 21.058 20.161 4.0 21.559 20.641 5.0 22.060 21.121 6.0 22.561 21.601 101.0 130.269 125.568 102.0 132.333 127.575 103.0 134.397 129.582 104.0 136.461 131.589 105.0 138.525 133.596 106.0 140.589 135.603 107.0 142.653 137.610 108.0 144.717 139.617 109.0 146.781 141.624 110.0 148.845 143.631 111.0 151.150 145.878 112.0 153.455 148.125 113.0 155.760 150.372 114.0 158.065 152.619 115.0 160.370 154.866 116.0 162.675 157.133 117.0 164.980 159.360 118.0 167.285 161.607 119.0 169.590 163.854 120.0 171.895 166.101 121.0 174.458 168.606 122.0 177.021 171.111 123.0 179.584 173.616 124.0 182.147 176.121 125.0 184.710 178.626 126.0 187.273 181.131 127.0 189.836 183.636 128.0 192.399 186.141 129.0 194.962 188.646 130.0 197.525 191.151 131.0 200.364 193.933 132.0 203.203 196.715 133.0 206.042 199.497 49.0 54.418 52.190 50.0 55.375 53.111 51.0 56.479 54.175 52.0 57.583 55.239 53.0 58.687 56.303 134.0 208.881 202.279 135.0 211.720 205.061 136.0 214.559 207.843 137.0 217.398 210.625 138.0 220.237 213.407 139.0 223.076 216.189 140.0 225.915 218.971 141.0 229.048 222.051 142.0 232.181 225.131 143.0 235.314 228.211 144.0 238.447 231.291 145.0 241.580 234.371 146.0 244.713 237.451 147.0 247.846 240.531 148.0 250.979 243.611 149.0 254.112 246.691 150.0 257.245 249.771 151.0 260.690 253.170 152.0 264.135 256.569 153.0 267.580 259.968 154.0 271.025 263.367 155.0 274.470 266.766 156.0 277.915 270.165 157.0 281.360 273.564 158.0 284.805 276.963 159.0 288.250 280.362 160.0 291.695 283.761 161.0 295.470 287.501 162.0 299.245 291.241 163.0 303.020 294.981 164.0 306.795 298.721 165.0 310.570 302.461 166.0 314.345 306.201 96.0 120.845 116.417 97.0 122.685 118.203 98.0 124.525 119.989 99.0 126.365 121.775 100.0 128.205 123.561 167.0 318.120 309.941 168.0 321.895 313.681 169.0 325.670 317.421 170.0 329.445 321.161 171.0 333.569 325.267 172.0 337.693 329.373 173.0 341.817 333.429 174.0 345.941 337.585 175.0 350.065 341.691 176.0 354.189 345.797 177.0 358.313 349.903 178.0 362.437 354.009 179.0 366.561 358.115 180.0 370.685 362.221 181.0 375.176 366.658 182.0 379.667 371.095 183.0 384.158 375.532 184.0 388.649 379.969 185.0 393.140 384.406 186.0 397.631 388.843 187.0 402.122 393.280 188.0 406.613 397.717 189.0 411.104 402.154 190.0 415.595 406.591 191.0 420.468 411.510 192.0 425.341 416.429 193.0 430.214 421.348 194.0 435.087 426.267 195.0 439.960 431.186 196.0 444.833 436.105 197.0 449.706 441.024 198.0 454.579 445.943 199.0 459.452 450.862 200.0 464.325 455.781
[0055] The apparatus and method of the preferred embodiment encompass the use of a mixture of refrigerants tetrafluoroethane and chlorodifluoroethane at preferred ranges, as discussed above, with lubricant at preferred ranges, as discussed above (0.5-20% by weight) in the operation of an HVAC/R system, wherein the coolant-oil mixture replaces Refrigerant R-12 (dichlorodifluoromethane) in a Refrigerant R-12 (dichlorodifluoromethane)-based refrigeration system.
[0056] The method and apparatus in the preferred embodiment further entails providing the above described mix of chlorodifluoroethane/1,1,1,2-tetrafluoroethane and lubricant in 25 lb cylinders, where the cylinders are pressure sealed and fitted with an outlet compatible for existing Refrigerant 12-type refrigeration manifolds typically ¼ inch male flare.
[0057] Further, it was noted that the systems tested ran more smoothly and the compressor showed less vibration during the test period, as the mixture was added. It is theorized that the lubricating oil, being soluble in the refrigerant gasses, was better able to lubricate the compressor and reciprocating parts than the existing Refrigerant R-12 (dichlorodifluoromethane) lubricant used by itself. In some applications, depending on the charge, a reduction in power consumption maybe also noted. The optimum percentage charge for this invention is at a 92% charge of the called for charge of the R-12 system being retrofitted.
[0058] Pure refrigerant 1,1,1,2-tetrafluoroethane is not miscible with naphthenic oil or mineral oil (both of which could be used as the lubricants of the present disclosure). Chlorodifluoroethane is miscible with most naphthenic oils such as alkylbenzene and also mineral oils. The presence of the chlorodifluoroethane allows the use of naphthenic oil alone or mixed with mineral oils in the refrigerant blend and system of the present invention (a translucent, partially miscible blend is formed). Alkylbenzene, when added to mineral oil, is accepted to provide improved lubricating qualities to those of mineral oil alone. The lubricant can advantageously be partially polymerized into longer chain molecules to allow it to function at very low percentage levels. The lubricant can be hydrotreated or polymerized for stability and wear resistance.
[0059] The lubricant of the present disclosure is miscible with R-12, R-22, and the blend of the refrigerant gases described herein.
[0060] Although exemplary embodiments have been shown and described, it will be clear to those of ordinary skill in the art that variations and modifications may be made of the refrigerant taught herein, and that those are within the scope and spirit of the invention as taught above and claimed here below. | An apparatus and method wherein potential ozone layer-damaging dichlorodifluoromethane (Refrigerant R-12) is substituted with a mix of less environmentally damaging refrigerants Chlorodifluoroethane and Tetrafluoroethane in dichlorodifluoromethane-based air-cooling systems, in particular HVAC and refrigeration applications. While less environmentally damaging than dichlorodifluoromethane, the substitute refrigerant is less flammable than presently available refrigerants, yet still has a temperature-pressure relationship close enough to that of dichlorodifluoromethane, making the substitute refrigerant suitable for use with dichlorodifluoromethane-based air-cooling systems. In this event, it is mixed with a lubricating oil that is compatible with both the unit refrigerant and typical R-12 system design. | 2 |
This application is a divisional application of application Ser. No. 12/779,288, filed May 13, 2010; now U.S. Pat. No. 7,910,730 which is a divisional application of application Ser. No. 12/092,825, now U.S. Pat. No. 7,902,357 filed Sep. 7, 2008; which is a national phase application of International Application Number PCT/GB2006/004293, filed Nov. 17, 2006, which claims priority to Great Britain Application No. 0523435.6, filed Nov. 17, 2005, all of which are incorporated herein by reference in their entirety.
FIELD OF THE INVENTION
The present invention relates to a process for the production of delmopinol or a derivative thereof, as well as to intermediates useful in the production process.
BACKGROUND TO THE INVENTION
Delmopinol is the International Non-proprietary Name (INN) of 3-(4-propylheptyl)-4-morpholinethanol (CAS No. 79874-76-3). Delmopinol hydrochloride salt (CAS No 98092-92-3) is intended to be used in the treatment of gingivitis. The structure of delmopinol hydrochloride corresponds to formula:
Different processes for the production of delmopinol and its salts are known in the art. EP-A-038785 describes several processes to produce this compound. In particular, EP-A-038785 disclosed the preparation of delmopinol by alkylation of a 3-substituted morpholine, by dialkylation of a primary amine with a substituted bis(haloethyl)ether or a substituted diethyleneglycol disulfonate, by reduction of a diketomorpholine, or by transformation of the N-substituent of the morpholone into a hydroxyethyl group. EP-A-0426826 describes a process for the production of delmopinol which comprises a cycloaddition from a morpholine oxide to obtain a morpholine-iso-oxazolidine, a reductive ring opening, followed by transformation of functional groups present in the side chain, and finally alkylation of the nitrogen to yield delmopinol.
The known processes to produce delmopinol are long and require the use of some very toxic reagents, which make their industrial exploitation difficult and expensive. Therefore, the provision of a new process for producing delmopinol is highly desirable.
SUMMARY OF THE INVENTION
The current invention is based on the surprising realisation that delmopinol, and derivatives thereof, can be obtained by a short and convergent synthesis which takes place through a reaction between an oxazolidin[2,3-c]morpholine compound and a Grignard compound.
According to a first aspect of the present invention, a process for the production of a compound of formula (I) wherein R 1 is an alkyl or aryl moiety, or a pharmaceutically acceptable salt, or a solvate thereof, including a hydrate,
comprises reacting a compound of formula (II) with a grignard compound of formula (III) where X is an halogen selected from Cl, Br and I and R 1 is an alkyl or aryl moiety, and optionally converting the compound of formula (I) free base obtained into a pharmaceutically acceptable salt.
The inventors have also found an efficient production process of the new oxazolidin [2,3-c]morpholine (II), starting from commercially available diethanolamine which proceeds with high yields and purity. Therefore, a second aspect of the present invention is the provision of a process for the production of oxazolidin[2,3-c]morpholine, which involves the reaction of diethanolamine with a (C 1 -C 4 )-alkyl haloacetate yielding the known 4-(2-hydroxyethyl)-morpholin-3-one, followed by a reduction reaction, to yield the oxazolidin[2,3-c]morpholine. Both steps can also be joined in a one pot reaction, avoiding the isolation of the 4-(2-hydroxyethyl)-morpholin-3-one.
According to a third aspect of the present invention, the production of a specific grignard compound (IIIA) is carried out by treatment of a 1-halo-4-propylheptane with magnesium.
According to a fourth aspect of the present invention is provided compounds (II) and (IIIA). These are useful as intermediates for the production of a compound of formula (IA).
According to a fifth aspect of the invention, compounds (II) and (III) are used in the manufacture of a compound of formula (I).
The process of the present invention is an easy and efficient alternative to manufacture delmopinol, derivatives of delmopinol and/or pharmaceutically acceptable salts thereof, on an industrial scale. The process is advantageous because it is a short and convergent synthesis, it avoids the use of toxic and flammable reagents, it uses mild reaction conditions, and delmopinol is obtained with high yields and high purity.
DETAILED DESCRIPTION OF THE INVENTION
A compound of formula (I) is produced according to the present invention.
In the compound of formula (I), R 1 is an alkyl or aryl moiety. The alkyl or aryl moiety can be of any length, can be straight-chain or branched and can be substituted, i.e. can contain atoms other than carbon in the carbon backbone. As used herein, the terms “alkyl” and “aryl” are to be given their usual meanings on the art. Preferably, the alkyl or aryl moiety comprises between 1 and 30 carbon atoms, more preferably between 2 and 20 carbon atoms, for example 6, 7, 8, 9 or 10 carbon atoms. Compounds of formula (I) have been prepared where the R 1 group is a 1-Propyl, Benzyl, 1-Octyl, 1-Heptyl, 1-(2-ethyl)hexyl or 1-(2-propyl)hexyl group. The preparation of these compounds is described in Examples 6 to 11.
A preferred compound of formula (I) is delmopinol, which is represented below as formula (IA). In delmopinol, R 1 is a 4-propylheptyl chain.
According to the present invention, a compound of formula (I) is obtained by a reaction between the oxazolidin[2,3-c]morpholine (II) and the Grignard compound (III) where X is an halogen selected from Cl, Br and I, and R 1 is an alkyl or aryl moiety as defined above and most preferably a 4-propylheptyl chain. A preferred compound of formula (III), wherein R 1 is a 4-propylheptyl chain is depicted as formula (IIIA) below.
Most preferably, the compound of formula (III) is 4-propylheptylmagnesium bromide. As used herein, the term “Grignard Compound” is to be given its standard meaning, which is well known in the art, i.e. an organo-magnesium compound.
For the avoidance of doubt, a compound of formula (I) is prepared by reacting a compound of formula (II) with a Grignard compound of formula (III). A preferred embodiment of this general reaction comprises the production of delmopinol (formula (IIIA) by reacting a compound of formula (II) with the preferred Grignard compound of formula (IIIA).
The formation of the Grignard compound (ill) and its subsequent reaction with the oxazolidine (II) is carried out in a suitable solvent such as ethers (C 4 -C 12 ) and mixtures of said ethers with (C 5 -C 8 ) aliphatic or (C 6 -C 8 ) aromatic hydrocarbons. Preferably the solvent is selected from the group consisting of diethylether, tetrahydrofuran, methyltetrahydrofuran, dibutylether and the following mixtures: tetrahydrofuran-toluene, tetrahydrofuran-xylene, methyltetrahydrofuran-toluene, methyltetrahydrofuran-xylene, dibutylether-xylene, dibutylether-toluene.
A compound of formula (I), for example delmopinol, obtained by the process of the present invention may be converted into a pharmaceutical acceptable salt, preferably into the hydrochloride salt, and delmopinol salts may be converted into delmopinol, by known methods described in the art. By a way of example, delmopinol hydrochloride can be prepared from delmopinol by reaction with hydrochloric acid in any suitable solvent. Examples of suitable solvents are, for instance, toluene, xylene, methylisobutylketone, dibutylether, methyl-tert-butylether, ethyl acetate, and mixtures thereof.
The compound of formula (II) can be obtained by the process summarised in Scheme I, which can be carried out in two steps or as a one pot reaction. As used herein, the term “one pot reaction” is to be given its normal meaning in the art, i.e. the compound of formula (II) is produced in a single reaction vessel, such that at least a proportion of compounds (V) and (VI) are converted to compound (IV), and subsequently compound (II), without the isolation of intermediates.
The alternative to a one pot reaction is a two step reaction wherein formula (IV) is produced in a first step, and the second step of converting (IV) into (II) is carried out separately.
In formula (VI), X is an halogen selected from Cl, Br and I, and R 1 is a (C 1 -C 4 )-alkyl radical. Preferably the compound of formula (VI) is methyl chloroacetate.
The reaction between the diethanolamine (V) and the haloacetate of formula (VI) is preferably carried out in the presence of a suitable base and a suitable solvent. Examples of suitable bases are sodium hydride, sodium metoxide, potassium tert-butoxyde and sodium tert-butoxide. The best results are obtained with potassium tert-butoxide. Suitable solvents are for example tetrahydrofuran, xylene, toluene or dibutylether.
The reaction between the diethanolamine (V) and the haloacetate (VI) can be carried out at a temperature between room temperature and the reflux temperature of the solvent used. Preferably, the reaction is carried out at high temperatures (i.e. slightly less than the reflux temperature of the solvent, for example 50% of the reflux temperature or above, preferably 60%, 70%, 80% or 90% of the reflux temperature) to avoid thickness of the crude mixture by insolubility of diethanolamine alkoxyde at low temperatures. Compound (IV) can be isolated from the reaction medium with high yield as an oil, which can be used without purification in the next step. If required, it can be purified by distillation.
3-Morpholinone (IV) can also be prepared by a process described in the literature (Australian Journal of Chemistry, 1996, vol. 49, pp. 1235-1242). However, this process uses an excess of acylating reagent, it goes through an unstable intermediate and proceeds with low yields.
The reduction of 3-morpholinone (IV) to yield the oxazolidine (II) is carried out using a reducing agent. Examples of reducing agents are sodium bis(2-methoxyethoxy)aluminum hydride (Vitride), sodium borohydride, lithium aluminium hydride and sodium bisethoxyaluminum hydride. A preferred reducing agent is sodium bis(2-methoxyethoxy)aluminum hydride. The reduction reaction is carried out in a solvent selected from a (C 6 -C 8 ) aromatic hydrocarbon such as toluene or xilene and an ether (C 4 -C 12 ) such as diethylether, tetrahydrofuran, dibutylether, methyl tert-butylether, and diethyleneglycol dibutyl ether.
Preferably, when the process of producing the compound of formula II is carried out in one pot, the alcohols generated during the reaction between the diethanolamine and the compound of formula (VI) are distilled before adding the reducing agent.
The compound of formula (III) can be produced by reacting an alkyl or aryl halide with magnesium. Preferably, the halide is in the terminal or secondary position. In a preferred embodiment, as illustrated in Scheme II, the compound of formula (IIIA) is previously prepared by treating a compound of formula (VII) wherein X is an halogen selected from Cl, Br, and I, with magnesium. Any suitable solvent for Grignard reactions such as ethers (C 4 -C 12 ) and mixtures of such ethers with (C 5 -C 8 ) aliphatic or (C 6 -C 8 ) aromatic hydrocarbons can be used for the formation of Grignard compound. The Grignard compound of formula (III) is not isolated and is used in solution. Its formation is easily detectable by the disappearance of magnesium and the brownish colouration of the solution.
The compound of formula (VII) can be prepared from the corresponding hydroxy compound of formula (VIII) by an halogenation reaction.
Preferably in the compound of formula (VII), X is bromine and is preferably obtained by a brominating reaction of the compound (VIII) with aqueous hydrobromic acid. The compound of formula (VIII) can be prepared by the process described in Justus Liebigs Annalen Chemie, 1966, vol. 693, p. 90, the content of which is hereby incorporated by reference.
Throughout the description and claims the word “comprise” and variations of the word, such as “comprising”, are not intended to exclude other technical features, additives, components, or steps. Additional objects, advantages and features of the invention will become apparent to those skilled in the art upon examination of the description or may be learned by practice of the invention.
The following examples are provided by way of illustration, and are not intended to be limiting of the present invention.
EXAMPLES
Example 1
Production of 4-(2-hydroxyethyl)morpholin-3-one (IV)
Potassium tert-butoxyde (176 g, 1.1 eq.) was added to 1440 ml of toluene. The suspension was heated to 75° C. and maintained for 30 minutes until complete dissolution of the white solid. At this temperature diethanolamine (150 g, 1 eq.) was slowly added. The thick pale yellow suspension was maintained with strong stirring for 30 minutes and methyl chloroacetate (163 g, 1.05 eq.) was added slowly. The solution was maintained at the same temperature for two hours. To the warm mixture methanol (600 ml) was added and cooled at room temperature, salts were filtrated and the organic layer concentrated until dry. Compound (IV) was obtained as an orange oil (204 g, 98%) which was distilled under high vacuum to obtain it as a highly pure colorless oil (80%, bp5 180° C.). IR (film) (n cm-1): 3410, 2934, 2874, 1633, 1501, 1350, 1141. MS (EI), (m/z, %): 145 (M+, 12), 114 (M-CH2OH, 100), 86 (M-NC2H4OH, 65), 74 (M-71, 7), 56 (M-89, 41), 42 (M-103, 44).
Example 2
Production of oxazolidin[2,3-c]morpholine (II)
To a solution of 3-morpholinone (IV) (207 g, 1 eq.) in toluene (1450 ml), Vitride solution (412 g, 2 eq., 70% in toluene) was slowly added at room temperature. The reaction was maintained for 15 min at this temperature. 50% aqueous sodium hydroxide solution (360 g, 3.15 eq.) was slowly added keeping the mixture at room temperature. The mixture was warmed to 50-60° C. and the aqueous layer was separated and extracted at the same temperature with toluene (924 ml). Both organic layers were concentrated together until dry. Oxazolidine (II) was obtained (154.5 g, 84%) as a brownish oil, which was distilled to give a highly pure colorless oil (65 g, bp2 80° C.). IR (film), (n cm-1): 2865, 1676, 1457, 1297, 1113, 1046. MS (EI), (m/z, %): 129 (M+., 50), 99 (M-CH2O, 100), 98 (M-CH3O, 90), 84 (M-C2H5O, 10), 71 (M-C3H6O, 51), 56 (M-73, 37), 42 (M-87, 47), 41 (M-88, 65).
Example 3
Production of oxazolidin[2,3-c]morpholine (II) in a One-Pot Reaction Starting from Diethanolamine
Potassium tert-butoxyde (176 g, 1.1 eq.) was added to 1440 ml of toluene. The suspension was heated to 75° C. and maintained for 30 min. until complete dissolution of the white solid. At this temperature diethanolamine (150 g, 1 eq.) was added slowly. The thick pale yellow suspension was maintained with strong stirring for 30 min. and methyl chloroacetate (163 g, 1.05 eq.) was added slowly. The solution was maintained at the same temperature for two hours. Reaction mixture was cooled at 30° C. and Vitride solution (412 g, 2 eq., 70% in toluene) was added slowly at room temperature. The reaction was maintained for 30 min at this temperature. 50% aqueous sodium hydroxide solution (360 g, 3.15 eq.) was added slowly keeping the mixture at room temperature. The mixture was warmed to 50° C. and the aqueous layer was separated and extracted at the same temperature with toluene (924 ml). Both organic layers were concentrated together until dry. Oxazolidine (II) was obtained (147 g, 80%) as a brownish oil.
Example 4
Production of 4-(2-hydroxyethyl)-3-(4-propylheptyl)morpholine (IA)
To a suspension of 1.3 g of magnesium (1 eq.) in 24 ml of toluene and 18 ml of tetrahydrofuran a small crystal of iodine was added. The mixture was heated at 64° C. and 12 g of 1-bromo-4-propylheptane (VII) (1 eq.) was added slowly controlling exothermicity of the reaction. The mixture was maintained at the same temperature for 2 hours and cooled at room temperature, obtaining a solution of compound (III). A solution of 7 g of oxazolidine (II) (1 eq.) in 7 ml of toluene was added to the previously prepared Grignard compound (III) at room temperature in 30 min. 50 ml of toluene and 50 ml of saturated aqueous ammonium chloride solution were added and the resulting mixture was stirred at 40° C. until complete dissolution of salts, obtaining a biphasic mixture. The organic layer was separated at 40° C. The aqueous layer was extracted with 50 ml of toluene at 40° C. Organic layers were concentrated together till dry, obtaining 8.8 g of 4-(2-hydroxyethyl)-3-(4-propylheptyl)morpholine as an orange oil. IR (film), (n cm-1): 3446, 2951, 2925, 2859, 1628, 1458, 1128, 1048. MS (EI), (m/z, %): 271 (M+., 1), 270 (M-H, 1), 240 (M-CH2OH, 46), 130 (M-141, 100), 100 (M-171, 29).
Example 5
Production of 4-(2-hydroxyethyl)-3-(4-propylheptyl)morpholine Hydrochloride
To a solution of 7.4 g of crude 4-(2-hydroxyethyl)-3-(4-propylheptyl)morpholine in 22 ml of methyl iso-butyl ketone at room temperature concentrated hydrochloric acid (2.7 g, 1 eq.) was added. The solution was concentrated until dry at 60° C. The oil was dissolved again in 21 ml of methyl iso-butyl ketone the solution was seeded and stirred for 2 hours at 0° C. The white solid was filtered, washed with 20 ml of cold methyl iso-butyl ketone and dried to obtain 5.9 g of 4-(2-hydroxyethyl)-3-(4-propylheptyl) morpholine hydrochloride (delmopinol hydrochloride). 1H-NMR (CDCl 3 , 400 MHz), (d ppm): 0.88 (6H, m, H15), 1.2-1.4 (13H, m), 1.8-2.0 (2H, m), 2.8-3.4 (5H, m), 3.4-4.4 (6H, m). 13C-NMR (CDCl3, 400 MHz), (d ppm): 14.26 (C15), 19.47, 19.52 (C14), 22.87 (C10), 27.11 (C9), 33.25 (C11), 35.54, 35.62 (C13), 36.59 (C12), 49.25 (C5), 53.20 (C7), 55.93 (C3), 57.08, 59.89 (C8), 63.1, 63.2, 65.0 (C6), 67.7 (C2).
Example 6
Synthesis of 4-(2-Hydroxyethyl)-3-propylmorpholine (IB)
43 g of Oxazolidine(II) was dissolved in 215 ml of THF. At room temperature a solution of n-Propylmagnesiumchloride 20% in THF (172 g, 1 eq) was slowly added. The mixture was stirred for 15 minutes. Mixture was concentrated until dryness under vacuum and 100 ml of Toluene and 64 g of saturated aqueous Ammonium Chloride solution were added and the resulting mixture was stirred at room temperature until complete dissolution of salts obtaining a biphasic mixture. Organic layer was separated and aqueous layer was extracted with 265 ml of Toluene at room temperature. Organic layers were concentrated together until dryness, obtaining 33.4 g of 4-(2-Hydroxyethyl)-3-propylmorphoiine like a orange oil, which was further purified by column chromatography in silica gel eluting with a mixture of CH2Cl2/MeOH/NH3 (99/1/1), obtaining the mentioned product as a colorless oil. 1H-NMR (CDCl3, 300 MHz), (d ppm): 0.92 (3H, t, J=7.2 Hz, H11), 1.36 (4H, m, H9/H10), 2.36 (3H, m, H3/H7), 2.82 (1H, ddd, J1=12.3, J2=4.9, J3=3.0 Hz, H5), 2.94 (1H, ddd, J1=12.3, J2=7.8, J3=4.8 Hz, H5), 3.44 (1H, dd, J1=11.2, J2=6.9 Hz, H2), 3.88 (1H, dd, J1=11.2, J2=4.9 Hz, H2), 3.62 (1H, dd, J1=4.8, J2=7.8 Hz, H6), 3.67 (1H, dd, J1=7.8, J2=4.9 Hz, H6), 3.75 (2H, m, H8). 13C-NMR (CDCl3, 75 MHz), (d ppm): 14.3 (C11), 19.3 (C10), 29.2 (C9), 49.9 (C5), 54.6 (C7), 57.7 (C8), 59.5 (C3), 66.9 (C6), 70.4 (C2). IR (film), (n cm-1): 3444, 2958, 2863, 1456, 1366, 1129, 1052. MS (EI), (m/z, %): 173 (M+., 42), 142 (M-CH2OH, 100), 130 (M-C3H7, 100), 112 (M-C3H7-H2O, 14), 100 (M-73, 48), 84 (10), 71 (5), 56 (20), 42 (14).
Example 7
Of 4-(2-Hydroxyethyl)-3-(1-heptyl)morpholine (IC)
200 g of 1-Bromoheptane were slowly added at 65° C. to a suspension of 32.6 g of magnesium, 0.5 g of iodine and 2.4 ml of Dibromoetane in a mixture of 182 ml of THF and 400 ml of toluene. The reaction mixture was stirred at the same temperature for 3 h. When the formation of the corresponding Grignard compound was completed, the mixture was cooled down at room temperature and a solution of 158 g of Oxazolidine (II) in 500 ml of toluene was added in 1 hour. The mixture was stirred for 30 min. and then added to 795 ml solution of aqueous 5% HCl. The organic layer is decanted and concentrated until dryness. Compound (IC) was obtained as an orange oil (179 g). MS (EI), (m/z, %): 229 (M+., 1), 198 (M-CH2OH, 25). 130 (M-C7H15, 100), 112 (M-C7H15-H2O, 4), 100 (M-73, 30), 85 (5 56 (10), 41 (8).
Example 8
Synthesis of 4-(2-Hydroxyethyl)-3-benzylmorpholine (ID)
Following the same procedure described for (IC) and starting from 10 g of Benzyl chloride and 11 g of Oxazolidine (II), 7.9 g of compound (ID) was obtained as an light yellow oil. MS (EI), (m/z, %): 221 (M+., 1), 190 (M-CH2OH, 5), 130 (M-C7H7, 100), 91 (CH2C6H5, 8).
Example 9
Synthesis of 4-(2-Hydroxyethyl)-3-(1-octyl)morpholine (IE)
25 g of 1-Bromooctane were slowly added to a suspension of 3.5 g of magnesium and 7.5 mg of iodine in 41 ml of THF at 65° C. The reaction mixture was stirred at the same temperature for 2 h. When the corresponding Grignard compound was prepared, the mixture was cooled down at 5° C. and a solution of 16.7 g of Oxazolidine (II) in 40 ml of toluene was added in 1 hour. The mixture was stirred at 5° C. for 30 min. and the reaction was warmed up until room temperature. The mixture was added to an aqueous solution of 5% HCl and stirred for 30 min. The organic layer was decanted, dried and concentrated until dryness to obtain 19 g of the desired compound as a brown oil. MS (EI), (m/z, %): 243 (M+., 5), 242 (M-H, 5), 212 (M-CH2OH, 50), 198 (M-(CH2)2OH, 8), 130 (M-C8H17, 100), 112 (M-C8H17-H2O, 8), 100 (M-73, 30), 86 (8), 71 (8), 56(9), 41 (14).
Example 10
Synthesis of 4-(2-Hydroxyethyl)-3-(1-(2-ethylhexyl))morpholine (IF)
Following the same procedure described for (IE) and starting from 25.5 g g of 1-Bromo-2-ethylhexane bromide and 16.2 g of Oxazolidine (II), 19.8 g compound (IF) were obtained as an dark orange oil. MS (EI), (m/z, %): 243 (M+., 1), 214 (M-C2H5, 6), 212 (M-CH2OH, 11), 186 (M-C4H9, 4), 156 (8), 130 (M-C8H17, 100), 100 (46).
Example 11
Synthesis of 4-(2-Hydroxyethyl)-3-(1-(2-propylpentyl))morpholine (IG)
Following the same procedure described for (IE) and starting from 5.8 g g of 1-Bromo-2-propylpentane and 4 g of Oxazolidine (II), 3.3 g of compound (IF) were obtained as an dark yellow oil. MS (EI), (m/z, %): 243 (M+., 1), 212 (M-CH2OH, 8), 200 (M-C3H7, 6), 170 (10), 130 (M-C8H17, 100), 100 (50). | A process for the preparation of delmopinol (3-(4-propylheptyl)-4-morpholinethanol) or a derivative or a pharmaceutically acceptable salt, or a solvate thereof, including a hydrate, comprises reacting oxazolidin [2,3-c]morpholine and a Grignard reagent, and optionally converting the delmopinol (or derivative) free base into a pharmaceutically acceptable salt. The oxazolidin [2,3-c]morpholine and the Grignard reagent are useful as intermediates in the production process. | 2 |
FIELD OF INVENTION
The present invention is directed towards an apparatus and method of cleaning fabric, particularly fabric used in papermaking.
BRIEF DESCRIPTION OF THE PRIOR ART
In papermaking, endless belts, fabric, or screens are used to support the paper sheet while allowing water to be removed in the formation of paper. The dryer wires or screens used in papermaking through normal use become contaminated by impurities from interaction with the paper sheet. This reduces the screens permeability to air which results in a reduction of the screen's water and air handling capacity and possibly paper quality. Accordingly, to maintain a steady state operation it is necessary to keep the screen free from such impurities.
Historically, dryer screen cleaning has been done on a batch wash basis during machine shut downs using conventional showers. Such batch wash type of cleaning while the machine is producing paper is not possible since the excessive amount of water required would upset the drying process. Continuous dryer screen cleaning has been used by using showers that traverse the fabric with a single jet resulting in substantially reduced water usage as compared to a conventional shower. The nozzles employed are of standard design with an aperture on the order of 1 mm or slightly less which is similar to that used in conventional showers. The showers operate at conventional pressures on the order of 100-300 PSI. The effect of adding water to the process at this point can be further reduced by adding an air jet to remove the water from the fabric, heating the water, or locating the shower as far upstream in the fabric return loop as possible. In some cases, these techniques can not be used due to various restrictions but even with all of the above improvements, continuous cleaning of dryer screens is only feasible in grades that are less sensitive to streaking.
One suggested method of cleanings is set forth in U.S. Pat. No. 4,540,469. In this regard this patent suggests increasing the pressure of the water while maintaining the orifice size. It is stated that the increased velocity resulting from such a change, although resulting in a corresponding increase in water flow, will result in less water remaining in the fabric since more of the water passes through the drying wire. The nozzle size can be reduced in such a way that the total water flow is maintained at conventional levels with satisfactory results in a pressure range of 430 to 1300 PSI. The patent teaches that reducing the water flow further is disadvantageous because of the reduction in cleaning effect caused buy the narrower stream. The patent also teaches that the volume of water used at higher pressures is optimal if it increases with pressure since the higher amount of water used improves the cleaning but the water remaining in the fabric is maintained constant. This follows the conventional belief that cleaning is a function of water flow. Following this guideline, the water retained in the fabric can only be reduced by a factor which results from water carried through the fabric rather than deposited on it.
In the current cleaning of paper machine fabrics as aforesaid liquid jets or fans are sprayed onto the fabric. These jets rely on mechanical energy of the stream to dislodge contaminants, liquid flow to flood contaminants from the fabric, or chemical action to dislodge or loosen contaminants. This system has proved satisfactory in its general application in paper making. However, in the dryer section of the paper machine it can be problematic because the sheet is dry enough to be more sensitive to discontinuities of moisture in the fabric. If too much water is used to clean a dryer fabric, efficiency of the dryer is compromised. If only a single point of water is applied, the sheet can become streaked by the moisture streak left in the fabric by the shower. Typically, the single jet shower is used in conjunction with an air jet to drive the water from the fabric, but this approach is often inadequate.
Accordingly, it is desirable to improve upon the cleaning of screens, particularly dryer screens, which provides for efficient cleaning yet reduces or eliminates streaking.
SUMMARY OF THE INVENTION
It is therefore a principal object of the invention to provide for an improved means of cleaning fabric in a papermaking machine.
It is a further object to provide for such cleaning which precludes or reduces streaking or otherwise effects the quality of the paper. It is a further object to provide for such cleaning in dryer fabrics particularly, and fabrics generally. A yet further object is to provide for such cleaning by utilizing reduced water usage, and water retained in the fabric.
These and other objects are achieved by the present invention's use of ultra high pressure water jet(s) in the cleaning of paper maker's fabrics. In this regard, unlike conventional thinking which teaches that cleaning is dependent upon having both as large as possible nozzle size and as high a pressure as practical, cleaning and damage are related to the energy density of the stream applied to the fabric. A stream of fluid can be characterized in terms of the size of the hole producing the stream and the pressure of the fluid behind the hole. For needle jet type showers, these parameters can be directly translated to the fluid's mass flow rate and velocity. When such a stream impacts an object like a dryer screen, the force generated by the stream's impact is proportional to the product of the mass flow rate and velocity and the power generated is proportional to the mass flow rate times the velocity squared. If integrated over time, power becomes energy. Therefore adequate cleaning can be obtained using substantially reduced mass (water flow) provided that the velocity of the stream is increased proportionally. Damage to the fabric will not be increased provided that the total energy density (power times time divided by area) is not increased. Reducing the hole size of the nozzle will allow the flow rate to be reduced while increasing the pressure to achieve higher velocity. Cleaning and damage can thus be balanced by controlling energy application with greatly reduced water flow since the power increases with the square of velocity.
BRIEF DESCRIPTION OF THE DRAWING
Thus by the present invention its objects and advantages will be realized, the description of which should be taken in conjunction with the drawings wherein;
FIG. 1 is a perspective view of a high pressure pump and reduced nozzle for delivering the water to the nozzle for cleaning, incorporate the teachings of the present invention; and
FIG. 2 is a somewhat schematic view of the cleaning of a fabric using a high pressure stream, incorporating the teachings of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention provides for the effective cleaning of dryer fabrics or any other fabric while greatly reducing water streaks. It has been determined that the major effect of a water jet on a fabric where effect is measured as fabric damage or cleaning is proportional to the power applied to the fabric by the jet. Power is energy over time. Energy is 1/2 mv 2 , that is, one half of the mass of the water times the square of its velocity as it impinges the fabric. When water flows through an orifice, its velocity is proportional to the square root of the pressure behind the nozzle. Mass flow is proportional to velocity and the area of the orifice. For example, a conventional shower might use a 0.040 in. diameter nozzle operating at 300 psi and apply about 40 watts to the fabric with a volume flow of 0.515 gpm. The present invention can apply an equivalent energy using much higher pressure and a much smaller orifice. For example, 40 watts can be achieved through a 0.010 inch diameter nozzle with a pressure of about 1600 psi, resulting in a volume flow of 0.067 gpm. This greatly reduced flow will preclude streaks.
Turning now more particularly to the drawings, FIG. 1 is a schematic representation of the ultra high pressure (system 10) of the present invention. The system 10 may be implemented through appropriate modifications of the PROJET® shower currently available from AES Engineered Systems Inc., 436 Quaker Rd., P.O. Box 7010, Queensbury, N.Y. 12804. In general the PROJET® System provides for a shower for cleaning fabric particularly papermakers fabric. This comprises a jet or nozzle which traverses the fabric spraying water on the fabric. The typical nozzle speed is one nozzle diameter per revolution of the fabric. The PROJET® shower is modified to accept the present system in two ways: a high pressure hose 12 is substituted for the standard hose, and a small orifice sapphire nozzle 14 is used. A high pressure pump 16 pressurizes the water to the desired pressure, usually 1800 psi. This pressure 1800 psi provides a factor of reserve of 200 psi over the conventional 40 watts of cleaning power. A water inlet regulator 18 and filter 20 are coupled to pump 16 along with a pressure relief valve 22 between the pump 16 and nozzle 14. Also an air inlet regulator 24 is provided with air gauge 26 which is coupled to pump 16 to drive the same. Any pump of adequate volume and pressure capabilities can be used.
A fine filter 28 e.g. 60 microns is provided prior to the nozzle 14. The nozzle 14 is supported by a cart 30 which runs along a track 32 shown schematically in FIG. 2. An example of such a track arrangement is disclosed in U.S. Pat. No. 4,701,242, the disclosure of which is incorporated herein by reference.
At the aforesaid high pressure with the small diameter, it has been found that the effected area of cleaning of the high pressure nozzle 14 is at least three times its diameter. The nozzle can therefore be run at least three times the typical speed used in the PROJET® system, if desired.
In FIG. 2 there is shown a second embodiment. In this embodiment three nozzles are maintained on a manifold 34. These are coupled to a cart (not shown) which runs along the track 32 which traverses the fabric 36. The streams 38 of fluid impacting the fabric 36 are shown. Arrow 46 indicates the travel directions of the fabric. While one nozzle can provide sufficient cleaning, the three nozzles provide a factor of safety for cleaning and provide the opportunity to speed the shower traverse rate if fabric cleaning differentials across the fabric face become a problem. The manifold 32 is mounted such that it can be rotated about an axis more or less perpendicular to the fabric 36. Rotation of the manifold 32 causes the spacing between nozzle paths to change. Nozzle alignment on the fabric can thus be adjusted. Even with three nozzles, a substantial advantage in applied volume over conventional pressure showering is provided. This invention can further be utilized on conventional oscillated showers, such as that described in U.S. Pat. No. 4,598,238 where the nozzles would be modified to be very small and pressure made very high, as previously described herein.
Thus by the present invention its objects and advantages are realized and although preferred embodiments have been disclosed and described in detail herein its scope should not be limited thereby, rather its scope should be determined by that of the appended claims. | A method and apparatus for cleaning dryer fabrics and the like comprising an ultra high pressure water jet or jets at reduce water volume. | 3 |
PRIORITY STATEMENT
[0001] This non-provisional application is a continuation-in-part of, and claims priority under at least one of 35 U.S.C. Section 365(c) and 35 U.S.C. Section 120 of, prior International Application No. PCT/SE2006/000345 filed Mar. 17, 2006, which designated the United States of America and which claims priority on Swedish Patent Application number 0500616-8 filed Mar. 18, 2005, the entire contents of each of which is hereby incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates to a wake-up device for generating a control signal comprising a sensor for detecting an input signal, and an electrical circuitry for processing the detected input signal and generating said control signal. The present invention also relates to a method for generating a control signal from a wake-up device.
BACKGROUND OF THE INVENTION
[0003] Wireless systems are today used in a vast amount of applications. Such systems can be utilized for continuous transfer of data as well as intermittent data transfer. Standards, like e.g. Bluetooth™, have therefore been developed for enabling the implementation of such wireless systems.
[0004] Considering wireless systems in general, the overall power consumption can be derived from the actual transfer of data signals (e.g. an audio signal, a video signal or similar), and from the establishment of communication between the wireless system devices. In cases where the wireless system is used for intermittent data transfer, different solutions apply in order to reduce the power consumption due to establishment of communication between the devices. The devices may for instance comprise an internal clock and a computer program, allowing the communication to occur at different predetermined instants of time. If the internal clocks of the different wireless system devices are synchronized, one device will begin to “look” for data, and at the same time a corresponding device will begin to transmit data. In the time gap between the predetermined instants of time, the devices may be in a sleep-mode, thereby reducing the overall power consumption of the wireless system.
[0005] SE-0500616-8 discloses a method for unlocking a lock by a lock device enabled for short-range wireless data communication in compliance with a communication standard. The method further involves the introductory steps of detecting the presence of a user in a vicinity of said lock device and in response triggering performance of detecting a key device within operative range of the lock device. This allows the lock device to rest in a sleep mode with negligible power consumption during periods of inactivity. Only elements that handle the detection of the user's presence will need to be active during such a sleep mode. In turn, such optimum power preservation allows implementing the lock device as a stand-alone device that may operate autonomously for long periods of time, powered by its own power source such as batteries.
[0006] The presence of the user may be detected by receiving a detection signal from a proximity sensor positioned and adapted to monitor the vicinity of said lock device. The proximity sensor may be selected from the group consisting of: an IR (Infra-Red) sensor, an ultra-sound sensor, an optical sensor, an RF (Radio Frequency) sensor or a pressure sensor.
[0007] The above technique suffers from certain drawbacks. Firstly, such detection of the user's presence may induce several unintentional activations of the radio communication. Secondly, such proximity sensor requires an increased need of service and maintenance of the wireless system.
SUMMARY OF THE INVENTION
[0008] In view of the above, an objective of the invention is to solve or at least reduce the problems discussed above.
[0009] A specific objective of the present invention is to provide a wake-up device that detects knocks.
[0010] This is generally achieved by the attached independent patent claims.
[0011] A first aspect of the invention is a wake-up device for generating a control signal comprising a sensor for detecting an input signal, that comprises at least one knock, and an electrical circuitry for processing the detected input signal and generating said control signal. Thus, the wake-up device can be mounted inside existing housings, e.g. doors, and the number of unintentional activations is reduced.
[0012] The sensor may be selected from the group consisting of acoustic sensors and vibration sensors, and more particularly from the group consisting of microphones and accelerometers. This is advantageous in that equipment known per se can be used.
[0013] The electrical circuitry may be configured to detect at least one of the signal intensity, the number of knocks and the frequency distribution of the input signal, which is advantageous in that the knock may be distinguished from noise.
[0014] The electrical circuitry may comprise a filter for filtering the input signal, which is advantageous in that a knock may be even better distinguished from noise.
[0015] The filter may be a band pass filter, which is advantageous in that equipment known per se can be used.
[0016] The electrical circuitry may be configured to apply a predetermined criteria to the detected input signal for deciding whether or not the control signal should be generated. This is advantageous in that a complex or coded knock pattern may be used as input signal.
[0017] A second aspect of the present invention is a method for generating a control signal from a wake-up device. The method comprises the steps of detecting at least one knock as an input signal, processing the detected signal, and generating said control signal.
[0018] At least one of the signal intensity, the number of knocks and the frequency distribution of the input signal may be detected.
[0019] The detected input signal may further be filtered, preferably by means of a band pass filter.
[0020] A predetermined criteria to the detected input signal for deciding whether or not the control signal should be generated may be applied.
[0021] The advantages of the first aspect of the invention are also applicable for this second aspect of the invention.
[0022] Other objectives, features and advantages of the present invention will appear from the following detailed disclosure, from the attached dependent claims as well as from the drawings.
[0023] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to “a/an/the [element, device, component, means, step, etc]” are to be interpreted openly as referring to at least one instance of said element, device, component, means, step, etc., unless explicitly stated otherwise. All references to “a knock” are to be interpreted openly as referring to at least one impact on a surface. Such impact may be performed by a human finger, fist, foot or other body part, any tool or object operated by a human, etc. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The above, as well as additional objectives, features and advantages of the present invention, will be better understood through the following illustrative and non-limiting detailed description of embodiments of the present invention, with reference to the appended drawings, where the same reference numerals will be used for similar elements.
[0025] FIG. 1 is a schematic illustration of a telecommunication system, including a wireless key device implemented by a mobile terminal, an embodiment of a wireless lock device for a lock in a door, a wireless administrator device implemented by a mobile terminal, an administrator server, a mobile telecommunications network and a couple of other elements, as an example of an environment in which the present invention may be applied.
[0026] FIG. 2 is a schematic front view illustrating the wireless key device of FIG. 1 , and in particular some external components that are part of a user interface towards a user of the wireless key device.
[0027] FIG. 3 is a schematic block diagram illustrating internal components and modules, including one embodiment of the present invention, of the wireless lock device as shown in FIG. 1 .
[0028] FIG. 4 is a schematic view of one embodiment of the present invention.
DETAILED DESCRIPTION OF EMBODIMENTS
[0029] The present invention may advantageously be implemented in a mobile telecommunications system, one example of which is illustrated in FIG. 1 and further described in SE-0500616-8. Central elements in FIG. 1 are a wireless key device (KD) 100 and a wireless lock device (LD) 140 . The purpose of the lock device 140 is to control some sort of lock mechanism in a lock, which in the illustrated example is a door lock on a door 150 . In turn, the lock device 140 is operated by the key device when brought in the vicinity of the lock device. In more particular, both the key device 100 and the lock device 140 are enabled for short-range wireless data communication in compliance with a communication standard. In the preferred embodiment, this communication standard is Bluetooth™. Having been the de facto standard for short-range wireless data communication for mobile devices during several years already, Bluetooth™ is believed to be very well known to the skilled person, and no particulars about Bluetooth™ as such are consequently given herein.
[0030] As with most other contemporary mobile telecommunications systems, the system of FIG. 1 provides various telecommunications services such as voice calls, data calls, facsimile transmissions, music transmissions, still image transmissions, video transmissions, electronic message transmissions and electronic commerce for mobile terminals in the system, such as aforementioned mobile terminal 100 , another mobile terminal 106 , personal digital assistants (PDA) or portable computers. It is to be noticed that these various telecommunications services are not central to the invention, and for different embodiments, different ones of the telecommunications services may or may not be available.
[0031] In FIG. 1 , the key device 100 is implemented by any commercially available, Bluetooth™-enabled mobile terminal 100 , one embodiment 200 of which is shown in FIG. 2 . As seen in FIG. 2 , and as is well known in the art, the mobile terminal 200 comprises an apparatus housing 201 , a loudspeaker 202 , a display 203 , an input device 204 a - c , and a microphone 205 . In the disclosed embodiment, the input device 204 a - c includes a set of keys 204 a arranged in a keypad of common ITU-T type (alpha-numerical keypad), a pair of soft keys or function keys 204 b , and a biometrical data reader 204 c in the form of a fingerprint sensor. Hence, a graphical user interface 206 is provided, which may be used by a user of the mobile terminal 200 to control the terminal's functionality and get access to any of the telecommunications services referred to above, or to any other software application executing in the mobile terminal. The keypad 204 a may be used for entering a PIN code to be used for authenticating the key device 100 in the lock device 140 in order to decide whether or not to unlock the lock controlled by the lock device. The biometrical data reader 204 c may be used correspondingly to produce a digital fingerprint sample from the user, said fingerprint sample being used for authenticating the key device 100 in the lock device 140 by matching with prestored fingerprint templates.
[0032] In addition, but not shown in FIG. 2 , the mobile terminal 200 of course comprises various internal hardware and software components, such as a main controller (implemented e.g. by any commercially available Central Processing Unit (CPU), Digital Signal Processor (DSP) or any other electronic programmable logic device); associated memory, such as RAM memory, ROM memory, EEPROM memory, flash memory, hard disk, or any combination thereof; various software stored in the memory, such as a real-time operating system, a man-machine or user interface, device drivers, and one or more various software applications, such as a telephone call application, a contacts application, a messaging application, a calendar application, a control panel application, a camera application, a mediaplayer, a video game, a notepad application, etc; various I/O devices other than the ones shown in FIG. 2 , such as a vibrator, a ringtone generator, an LED indicator, volume controls, etc; an RF interface including an internal or external antenna as well as appropriate radio circuitry for establishing and maintaining an RF link to a base station; aforementioned Bluetooth™ interface including a Bluetooth™ transceiver; other wireless interfaces such as WLAN, HomeRF or IrDA; and a SIM card with an associated reader.
[0033] The mobile terminals 100 , 106 are connected to a mobile telecommunications network 110 through RF links 103 , 108 via base stations 104 , 109 . The mobile telecommunications network 110 may be in compliance with any commercially available mobile telecommunications standard, such as GSM, UMTS, D-AMPS or CDMA2000.
[0034] The mobile telecommunications network 110 is operatively connected to a wide area network 120 , which may be Internet or a part thereof. Various client computers and server computers, including a system server 122 , may be connected to the wide area network 120 .
[0035] A public switched telephone network (PSTN) 130 is connected to the mobile telecommunications network 110 in a familiar manner. Various telephone terminals, including a stationary telephone 132 , may be connected to the PSTN 130 .
[0036] The lock device 140 is a stand-alone, autonomously operating device which requires no wire-based installations, neither for communication nor for power supply. Instead, the lock device 140 is powered solely by a local battery power unit 303 and interacts with the key device, as already mentioned, by Bluetooth™-based activities. To this end, the lock device 140 has a Bluetooth™ radio module 309 with an antenna 310 .
[0037] The lock device 140 of the present embodiment further includes a real-time clock 304 capable of providing the CPU 313 which an accurate value of the current time. A detector 312 b may be positioned to detect that the door 150 is in a properly closed position, so that the CPU 313 may command locking of the lock 160 a certain time after a user has opened the door through the key device 100 and passed therethrough. The detector 312 b may be a conventional magnetic switch having a small magnet mounted to the door frame and a magnetic sensor mounted at a corresponding position on the door leaf.
[0038] The lock device 140 may have a simple user interface involving button(s) 305 , a buzzer 312 a and LED indicator(s) 312 c . In some embodiments, an authorized administrator (ADM) may configure the lock device 140 through this user interface. In other embodiments, though, configuration of the lock device 140 —including updating the contents of a local database (LD-DB) 142 stored in memory 311 and containing i.a. key device authentication data—occurs wirelessly either directly from a proximate mobile terminal 106 over a Bluetooth™ link 116 , or by supplying a key device, for instance key device 100 , with authentication data updating information from a system database 124 at the system server 122 over the mobile telecommunications network 110 .
[0039] Since the lock device 140 is a stand-alone, battery-powered installation which is intended to be operative for long time periods without maintenance, it is important to keep power consumption at a minimum. Therefore, the present system is designed to put itself in a sleep mode after a certain period of inactivity. In the sleep mode, the elements of the lock device 140 are inactive and consume negligible power. The way to exit the sleep mode and enter operational mode is by applying a wake-up control signal 326 on a particular control input on the CPU 313 . To this end, the lock device 140 is provided with a wake-up arrangement 320 according to one embodiment of the present invention.
[0040] In FIG. 4 , one embodiment of the present invention is shown. The wake-up arrangement 320 has a sensor such as an acoustic or vibration sensor 324 which may be adapted to detect knocks on a door leaf. Such a sensor may be provided in the form of a microphone which may be attached via a spacer to the door leaf. The spacer will then transfer vibrations caused by door knocks to the microphone. The circuitry 322 may be programmed or designed to apply predetermined wake-up criteria when decided whether or not to generate the wake-up control signal 326 . Such wake-up criteria may for instance be related to the intensity of the knock(s), the number of knocks, and/or the frequency distribution or rhythm of the knocks. Thus, the wake-up criteria may be the detection of more than one door knock within a certain time frame. This may prevent an accidental wake-up because of a spurious detection of a non-related sound from the environment. Even more advanced wake-up criteria may be used, such as a given sequence of short and long door knocks, much like a code of Morse signals.
[0041] In more detail, the electric circuitry 322 may comprise an amplifier 328 , a filter 330 , a comparator 334 for comparing the filtered signal with an intensity reference level 332 , and a processor 336 .
[0042] The signal detected by the sensor 324 is thus amplified by the amplifier 328 , and thereafter filtered by the filter 330 . The filter 330 may preferably be a band pass filter of any type known per se. The amplified and filtered signal is compared to the reference level 332 by a common comparator 334 , in order to reduce the number of unintentional wake-up operations. If the filtered signal exceeds the reference level 332 , the signal is further processed by the processor 336 .
[0043] The processing step may include several partial steps, depending on the level of processing. The processor 336 may be programmed to determine the intensity of the signal. It may further be programmed to determine the number of knocks in the signal, as well as it may be programmed to determine the frequency distribution of the signal. By determining such frequency distribution, the “rhythm” of a number of knocks may be determined.
[0044] Further, the processor 336 may be configured to apply a predetermined criteria to the detected input signal for deciding whether or not the control signal should be generated. Such criteria may be fulfilled if the signal intensity exceeds a certain pre-programmed value. Such criteria may also be fulfilled if the number of knocks equals a certain pre-programmed value of number of knocks. Further, such criteria may also be fulfilled if the frequency distribution or “rhythm” of the number of knocks in the input signal corresponds to a pre-programmed “rhythm”.
[0045] If the detected input signal fulfils the predetermined criteria, a control signal 326 may be generated. The control signal may be configured to turn an electronic system from sleep mode to operation mode.
[0046] Another system in which the present invention may be implemented will now be described. A wake-up device according to the present invention may be arranged in a door or a window on a house which is subject to surveillance by e.g. security officers. By knocking on the door or window, the wake-up device according to the present invention decides whether or not a control signal should be generated. If a control signal is generated, a radio communication is established between a key device carried by the security officer, and a stationary device positioned inside the building. Provided that the key device matches the stationary device, the radio communication will ensure that the presence of the security officer is logged.
[0047] The wake-up device according to the present invention may further comprise an internal memory circuit being connected to a locally stored database. The database may contain information about different knock patterns, and identification data corresponding to each knock pattern. The wake-up device may thereby, together with the control signal, also generate a signal comprising information about the detected pattern and hence user information corresponding to the detected pattern. For the surveillance system described above, each security officer may have a unique knock pattern. Even if the security officers share the same key device, the wake-up device according to the present information will send information about the user to the surveillance system.
[0048] The invention has mainly been described above with reference to a few presently preferred embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the invention, as defined by the appended patent claims. The invention may for instance just as well be used for controlling other kind of objects than described above, including but not limited to garage ports and various other equipment at homes, offices or public buildings. The present invention may be implemented in a medicine cabinet, as well as safety locks etc. | A wake-up device for generating a control signal is presented. The wake-up device comprises a sensor for detecting an input signal, that comprises at least one knock, and an electrical circuitry for processing the detected input signal and generating said control signal. Further, a method for generating a control signal from a wake-up device is also presented. | 4 |
BACKGROUND OF THE INVENTION
The present application claims priority to U.S. Provisional Patent Application Ser. No. 60/565,372, filed Apr. 26, 2004.
The present invention relates to an intercooler, and more particularly to a tube intensive intercooler assembly.
A multitude of systems for increasing the amount of air, and, concomitantly, fuel to an engine are well known. The concept of boosting charge, either with a turbocharger or supercharger, is well known. Moreover, the concept of using intercooling between a booster device, such as the turbocharger or supercharger, and the engine is also well known.
Intercooler or charge air cooler assemblies are relatively intricate systems which are typically manufactured from aluminum. Conventional intercooler assemblies utilize a multitude of flow passages which are cooled by air flowing over a multitude of fins which extend from external surfaces of the passages. Conventional intercoolers are “fin intensive” deigns in which a majority of the radiant cooling occurs through the metallic fins. Although effective, such conventional metallic intercooler assemblies are relatively heavy in weight and are also typically limited to rectilinear constructions.
Accordingly, it is desirable to provide a lightweight, thermally effective intercooler assembly which may be manufactured in a multitude of configurations.
SUMMARY OF THE INVENTION
A non-metallic intercooler assembly according to the present invention includes an intake header tank, an outlet header tank, and a multitude of non-metallic charge tubes which communicate airflow from the intake header tank to the outlet header tank. A multitude of non-metallic fins primarily provide structural support rather than thermal transfer as generally understood with a conventional aluminum radiator/intercooler system.
The intake header tank and the outlet header tank are manufactured from non-metallic or metallic materials. The multitude of non-metallic charge tubes and support side plates are manufactured of laser opaque material while the multitude of non-metallic fins are manufactured of laser transparent materials. The laser opaque and laser transparent materials are arranged and assembled to achieve an effective laser welding assembly process. The multitude of non-metallic charge tubes pass through the non-metallic fins and are laser welded thereto. As the multitude of non-metallic fins are laser transparent while the multitude of non-metallic charge tubes are laser opaque, the laser is readily directed to the desired location to assure a secure bond. Each of the non-metallic fins include an end section which is passed through a slot in the side plate and bent toward the side plate to provide a planar engagement surface to receive a laser weld. As the multitude of non-metallic fins are laser transparent while the side plates are laser opaque, the laser is readily directed from an external location to the planar engagement surface to assure a secure bond. The side plates are laser welded to an end cap which direct or collect the airflow to/from the multitude of non-metallic charge tubes and communicate airflow to/from the header tanks.
In another embodiment, the intercooler assembly is contoured to provide various shapes to facilitate installation in heretofore unavailable locations. In yet another embodiment, the multitude of non-metallic charge tubes are non-circular in cross-section to increase the packing density of the charge tubes and specifically tailor the size and shape of the intercooler assembly.
The present invention therefore provides a lightweight, thermally effective intercooler assembly which may be manufactured in a multitude of configurations.
BRIEF DESCRIPTION OF THE DRAWINGS
The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows:
FIG. 1 is a general schematic view of an exemplary boosted engine system embodiment for use with the present invention;
FIG. 2 is a perspective view of an air cooler assembly according to the present invention;
FIG. 3A is a block diagram of the air cooler assembly according to the present invention;
FIG. 3B is a block diagram of a PRIOR ART air cooler assembly utilizing thermal resistance values for comparison to the present invention utilized in FIG. 3A ;
FIG. 4 is an exploded view of an air cooler assembly according to the present invention;
FIG. 5 is an expanded view of a charge tube to fin laser interface according to the present invention;
FIG. 6 is an expanded view of a fin to side wall laser interface illustrating the fin planar engagement surface according to the present invention;
FIG. 7 is a front of an air cooler assembly according to the present invention;
FIG. 8 is an expanded view of a fin to end cap laser interface according to the present invention;
FIG. 9 is an expanded view of an end cap to header tank laser interface according to the present invention;
FIG. 10 is an expanded view of a conduit to header tank laser interface according to the present invention;
FIG. 11 is a front of another embodiment of an air cooler assembly according to the present invention;
FIG. 12 is a front of another embodiment of an air cooler assembly according to the present invention;
FIG. 13 is a top view of a charge tube packing arrangement as provided to a header tank;
FIG. 14 is a top view of a charge tube packing arrangement as provided to a header tank; and
FIG. 15 is a top view of another charge tube packing arrangement as provided to a header tank.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 illustrates a schematic view of a boosted engine system 10 . Generally, airflow from an intake 12 is communicated through an air cleaner 14 prior to communication to a compressor 16 of a booster such as a turbocharger 18 or supercharger. It should be understood that other systems may also be utilized to boost charge air. From the turbocharger 18 , compressed, heated, airflow (“charge airflow”) is communicated through an air-to-air intercooler assembly 20 to reduce the temperature thereof. From the intercooler assembly 20 , the cooler airflow is communicated to an engine 22 for combustion therein to provide a motive force. Exhaust from the engine 22 is communicated to a turbine 24 of the turbocharger 18 and exhausted through an exhaust system 26 .
It should be understood that although a particular component arrangement is disclosed in the illustrated embodiment, other components arrangements as well as various systems which will benefit from cooled air are also be usable with the present instant invention. The intercooler assembly 20 operates as an air-to-air heat exchanger to cool the charge air as generally understood. The cooled charge air decrease combustion temperature and increases the density of the charge air to increase the air packed into the combustion chambers. It should be further understood that systems which utilize an air-to-air heat exchanger other than motive source systems such as an air conditioning or thermal management system will also benefit from the present invention.
Referring to FIG. 2 , the intercooler assembly 20 includes an intake header tank 28 , an outlet header tank 30 and a multitude of non-metallic charge tubes 32 which communicate airflow from the intake header tank 28 to the outlet header tank 30 . Each of multitude of non-metallic charge 32 in one non-limiting embodiment may define an aspect ratio from 40:1 to 160:1. A multitude of non-metallic fins 34 extend transverse to the longitudinal axis of the multitude of non-metallic charge tubes 32 . The multitude of non-metallic charge tubes 32 pass through the fins 34 . Notably, relatively few fins 34 are utilized as the fins 34 primarily provide structural support rather than thermal transfer as generally understood with a conventional metal radiator/intercooler system. The fins 34 are mounted to non-metallic side plates 36 which interconnect the intake header tank 28 and the outlet header tank 30 to provide a relatively rigid structure.
Referring to FIGS. 3A , 3 B, the non-metallic intercooler assembly 20 designed according to the present invention is a “tube intensive” design. That is, the heat flow resistance on the greater volume provided by the tubes ( FIG. 3A ) is reduced as compared to the “fin intensive” deign of a conventional metallic intercooler/heat exchanger arrangement ( FIG. 3B ). The R values in FIGS. 3A and 3B are notional; however, the relative differences representationally distinguish between conventional intercooler designs ( FIG. 3B ) and the intercooler design according to the present invention ( FIG. 3A ). It should be understood that the tubes need not only be each individually larger than conventional designs, but will provide a larger volume of airflow due to a larger individual tube size, more numerous tubes, or a combination thereof as schematically illustrated. Most preferably, the multitude of non-metallic charge tubes 32 each provide a length to diameter aspect ratio of between 80:1 and 160:1. Furthermore, as the fins 34 are non-metallic, the fins provide almost no thermal dissipation properties, as non-metallic material are approximately one thousand times less useful than aluminum for thermal transfer properties.
The intake header tank 28 , an outlet header tank 30 may be manufactured from non-metallic or metallic materials. The multitude of non-metallic charge tubes 32 and the side plates 36 are preferably manufactured of laser opaque material while the multitude of non-metallic fins 34 are preferably manufactured of laser transparent materials. It should be understood that various combinations and arrangements of laser opaque and laser transparent materials may be utilized to achieve the desired laser welding assembly process disclosed herein. Laser welding is well known and the laser welder will only be schematically described as such laser welders themselves are commonly understood and form no part of the present invention.
Preferably, the non-metallic materials utilized in the present invention are thermal plastics. Most preferably, the non-metallic materials utilized herein are nylon 6, nylon 12, nylon 46, nylon 66, PPA, PPS, ABS, polycarbonate, PEEK, polypropylene, and PET. Laser opaque non-metallic materials are manufactured by injecting a carbon black dye into the non-metallic material, while the laser transparent material is manufactured by injecting an organic dye into the non-metallic material. The material may therefore be of generally the same appearance yet provide the necessary difference in laser welding properties. It should be understood that various textures may be utilize to identify the laser opaque from the laser transparent materials as well as provide various aesthetic effects
Referring to FIG. 4 , the intercooler assembly 20 is illustrated in an exploded view. The multitude of non-metallic fins 34 are located transverse to the longitudinal axis L of the multitude of non-metallic charge tubes 32 . The multitude of non-metallic charge tubes 32 pass through the non-metallic fins 34 and are laser welded thereto ( FIG. 5 ; only one tube shown). As the multitude of non-metallic fins 34 are preferably, laser transparent while the multitude of non-metallic charge tubes 32 are laser opaque, the laser is readily directed to the desired location to assure a secure bond.
Each of the non-metallic fins 34 include an end section 38 which is assembled through a slot 40 formed in the side plate 36 . The end section 38 is then bent toward the side plate 36 to provide a planar engagement surface to receive a laser weld ( FIG. 6 ; FIG. 7 ). As the multitude of non-metallic fins 34 are preferably, laser transparent while the side plates 36 are laser opaque, the laser is readily directed from an external location to the desired location to assure a secure bond.
The side plates 36 are laser welded to an end cap 42 , 44 . Each end cap 42 , 44 is essentially of a rectilinear trough shape to direct or collect the airflow to/from the multitude of non-metallic charge tubes 32 and communicate the airflow with the header tanks 28 , 30 . The end caps 42 , 44 include a U-shaped receipt portion 46 which receives the side plate 36 therein ( FIG. 8 ). Preferably, the end cap 42 , 44 is laser transparent and the side plates 36 are laser opaque. The laser is readily directed from an external location to the desired location to assure a secure bond.
The shape of the end cap 42 , 44 need not be rectilinear but may be of any shape to receive the multitude of non-metallic charge tubes 32 and provide an interface for the respective intake and outlet header tanks 28 , 30 ( FIG. 7 ; FIG. 9 ). That is, the end caps 42 , 44 are shaped to receive the respective intake and output header tanks 28 , 30 .
The intake and output header tanks 28 , 30 may be attached to the end caps 42 , 44 through fasteners F for intake and output header tanks 28 , 30 manufactured of a metallic material ( FIG. 9 ). Alternatively, the header tanks 28 , 30 may be manufactured of a non-metallic material and attached to the end caps 42 , 44 through laser welding ( FIG. 9 ).
Referring to FIG. 10 , a flexible laser transparent communication conduit 46 is laser welded directly to the laser opaque header tanks 28 , 30 . Laser opaque header tanks 28 , 30 provide laser welding to the laser transparent end caps 42 , 44 ( FIG. 9 ). By directly attaching the communication conduit 46 through laser welding, components such as hose clamps and tube barbs are eliminated which thereby increases reliability while minimizing expense, complexity and part count.
Referring to FIGS. 11 and 12 , additional embodiments of an intercooler assembly 20 ′ 20 ″ are illustrated. The intercooler assembly 20 ′, 20 ″ are contoured to provide various shapes by preferably adjusting the shape and/or length of the multitude of non-metallic charge tubes 32 ′, 32 ″. It should be further understood that the header tanks 28 ′, 28 ″, 30 ′, and 30 ″ although illustrated as generally rectilinear, may be shaped to further conform to a desired mounting location.
FIG. 11 illustrates curved non-metallic charge tubes 32 ′ which facilitate installation, for example, adjacent a wheel well. The intercooler assembly 20 ′ includes fins 34 ′ with a corrugated portion 35 such that the length of the fin is longitudinally variable in length during assembly. That is, the corrugated portions 35 permit the length of a single fin 34 ′ to be adjusted to fit various areas and provide some degree of flex to the intercooler assembly 20 ′ within a predetermined plane.
FIG. 12 illustrates a mechanically symmetrical intercooler assembly 20 ″ with header tanks offset for a predetermined installation such as in a raked front facia; chassis mounted; in front of engine cooling radiator; in front of air conditioning condenser; sandwiched between air conditioner and coolant radiator; under a headlight; under a bumper; and/or within a fog light opening. It should be understood that various installations will benefit from the present invention.
Referring to FIGS. 13-15 , the multitude of non-metallic charge tubes 32 may be packed in particular arrangements ( FIG. 13 ) and may alternatively or additionally be non-circular in cross-section. The multitude of non-metallic charge tubes 32 may be polygonal ( FIGS. 14 and 15 ) to increase the density of the tubes and may include various shape combinations so as to specifically tailor the size and shape of the intercooler assembly. Most preferably, the areas A between the non-metallic charge tubes 32 ( FIGS. 13 and 14 ) are filled to prevent airflow dead spaces within the header thanks 28 , 30 .
Although particular step sequences are shown, described, and claimed, it should be understood that steps may be performed in any order, separated or combined unless otherwise indicated and will still benefit from the present invention.
The foregoing description is exemplary rather than defined by the limitations within. Many modifications and variations of the present invention are possible in light of the above teachings. The preferred embodiments of this invention have been disclosed, however, one of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. For that reason the following claims should be studied to determine the true scope and content of this invention. | A non-metallic intercooler assembly includes an intake header tank, outlet header tank, and a multitude of non-metallic charge tubes which communicate airflow from the intake header tank to the outlet header tank. Several combinations of plastics parts are described. Tanks of intercoolers can be made from plastics today but with complicated clamping and sealing. Each tank in this description can be laser welded in place. Various combinations of laser opaque and laser transparent materials are utilized to achieve an effective laser welding assembly process. Intake systems for automotive use are widely made of plastic materials today and this description shows how those types of materials can be employed in an intercooler. Each non-metallic tube can be supported by a plastic fin feature whose primary function is to support the structure to promote airflow conditions favorable to heat transfer. | 1 |
FIELD OF INVENTION
[0001] The present invention relates to a method of identification and quantification of proteins, isoforms of angiotensin I converting enzyme (ACE), specifically ACE of 190-kDa, specially of 90 kDa (genetic marker of hypertension) and of 65 kDa in tissues, cells and biological fluids, specially in urine, a molecular marker based on said proteins, use of mentioned molecular marker, analytical method for diagnosis, risk stratification, therapeutical decision in carriers of arterial hypertension and primary or secondary renal lesion and kit for using in the diagnosis.
BACKGROUND OF THE INVENTION
[0002] The existence of two systems of vasoactive polypeptides, a hypertensor and a hypotensor, in mammal organism is quite new. The fundamental bases for understanding the hypertensor system, renin-angiotensin system were established through papers of Houssay and Fasciolo (1937), Houssay and Taquini (1938), Braun-Menendez, Fasciolo, Leloir and Muñoz (1939) and Kohlstaedt, Helmer and Page (1938). On the other hand, the hypotensor system, kallikrein-kinin system are based on Frey, Kraut and Werle papers, carried out in the 1930 decade (Frey, Kraut and Schultz, 1930; Kraut et al, 1930; Werle, 1936; Werle et al, 1937) as well as Rocha and Silva, Beraldo and Rosenfeld (1949) and Prado, Beraldo and Rocha e Silva (1950).
[0003] In the two systems the vasoactive peptide is released to its plasmatic protein precursor through limited proteolysis according to the following general scheme:
[0000]
[0004] Several papers on purification and characterization of proteases and substrates involved in these two systems allowed the clarification of several steps necessary for releasing the active peptide. However, the physiological role of the latter, as well as its catabolism is not totally clarified yet.
The Renin—Angiotensin System
[0005] Renin is an acid protease (E.C. 3.4.99.19), produced and stored by juxtaglomerular cells from afferent arteriole of the renal glomerulus (Kohlstaedt et al, 1938; Hartroft, 1963 and Tobian, 1960). The subtract under which this enzyme acts is a plasmatic α 2 -globulin, angiotensinogen, from which part of the N-terminal sequence is known (Braun-Menendez et al, 1939; Bumpus et al, 1958; Schwyzer and Turrian, 1960) which corresponds to: Asp 3 -Arg 2 -Val 3 -Tyr 4 -Ile 5 -His 6 -Pro 7 -Phe 8 -His 9 -Leu 10 -Leu 11 -Val 12 -Tyr 13 -Ser 14 .
[0006] When renin hydrolisates the Leu 10 -Leu 11 bond in the angiotensinogen molecule, decapeptide angiotensin I, which is as not very potent vasoconstrictor, is released. A second enzyme, described by Skeggs et al (1956), called converting enzyme, is the responsible by the hydrolysis of the Phe 8 -His 9 bond and by releasing octapeptide angiotensin II, which is pharmacologically active, being inactivated by angiotensinases.
The Kallikrein—Kinin System
[0007] The kallikrein-kinin system comprises kininogenases which hydrolisates an inactive precursor, the kininogen, and releases kinins, which are inactivated by kininases.
[0008] The expression kininogenase comprises proteases, such as: kallikreins, trypsin, pepsin, some bacterian proteases and snake poison (Prado, 1970; Rocha e Silva et al, 1949; Suzuki and Iwanaga, 1970). Among these enzymes, kallikreins are specifics for the system: these are serine-proteases that release kinins of the kininogen, by limited proteolysis (Neurath, 1975) and have low proteolitic activity on other proteins. Two types of kallikreins are found in mammals: glandular and plasmatic, which are different each other concerning to physical-chemical and immunological proprieties, reaction velocity with kininogen and synthetic subtracts, types of kinins released and responds to a great variety of synthetic and natural inhibitors.
[0009] On the other hand, kininogens are acid glycoproteins which contains a bradykinin molecule in the C-terminal or next to it (Pierce, 1968); they are hydrolisated by glandular kallikreins, releasing lysyl-bradykinin, as well as by plasmatic releasing bradykinin (Rocha e Silva, 1974). Lysyl-bradykinin is converted to bradykinin by the existing aminopeptidases contained in plasma (Erdös and Yang, 1970) as well in tissues (Hopsu et al, 1966 a, b; Borges et al, 1974; Prado et al, 1975).
[0010] Two kininogens functionally different have been described in plasma, namely, a high molecular weight kininogen, which is subtract for the two kallikrein (plasmatic and glandular), and a low molecular weight, which is a good subtract only for glandular kallikrein (Werle and Trautschold, 1963; Prado et al, 1971).
[0011] Bradykinin (BK=Arg 1 -Pro 2 -Pro 3 -Gly 4 -Phe 5 -Ser 6 -Pro 7 -Phe 8 -Arg 9 ), lysyl-bradykinin and methionyl-lysyl-bradykinin are strong physio-pharmaco-pathological agents, which produces hypotension and vasodilation, pain, contraction of the smooth muscle, increases vascular permeability and leukocyte migration (Erdös and Yang, 1970; Pisano, 1975).
Physiological Role of Kinins:
[0012] The action of kinins in the organism is not totally clarified, although some attributions have been indicated them as participating in several physiological functions, either at systemic or tissular levels.
[0013] It is proposed its mediation in different processes such as: peripheric vasodilatation and mediation in inflammatory phenomena; interaction with the synthesis system and prostaglandins release; mobility of spermatozoids; renal flux regulation; mediation in the sodium reabsorption by nephron (Wilhelm, 1973; Terragno et al, 1975; Baumgarten et al, 1970; Schill and Haberland, 1974; Levinsky, 1979).
[0014] In order to clarify the exact role carried out by kinins in this process, it is important to know not only the mechanism that leads to its release but also to its catabolism.
Catabolism of Kinins:
[0015] The responsible enzymes for inactivation of kinins are generically known as kininases. Under this acronym it is comprised a series of peptidases which are capable to hydrolysate the bonds in BK molecule or its derivatives, not being necessary or prove to be participant of the kinins catabolism.
[0016] Observations on the existence of such class of enzymes have been carried out since the initial researches of the kinins system and have been described in several organs, tissues and physiological liquids by many researchers groups.
Plasma
[0017] Two types of kininases have been characterized already in the human plasma: kininase I (arginine carboxypeptidase, E.C. 3.4.12.7) and kininase II (peptidyl-dipeptidase, E.C. 3.4.15.1).
[0018] Kininase I is a carboxypeptidase type enzyme, which was purified for the first time from Cohn fraction IV (Erdös e Sloane, 1962). This enzyme hydrolysates the Phe 8 -Arg 9 bonds of BK. It was originally called carboxypeptidase-N because of its proprieties, which make them different of pancreatic carboxypeptidase B. Although its official name, arginine carboxypeptidase, this enzyme catalyses better the lysine C-terminal hydrolysis than arginine, in many substrates (Oshima et al, 1975).
[0019] Among synthetic substrates used in the purification and specificity studies of such enzyme it can be cited the HLA (Oshima et al, 1975).
[0020] The second enzyme having kinin activity, described in plasma, is the kininase II, which inactivate BK by hydrolysis of the Pro 7 -Phe 8 bonds and releases Phe-Arg dipeptides (Yang and Erdös, 1967).
[0021] Later, it was observed that such enzyme is identical to the angiotensin I converting enzyme (AI) of the renin-angiotensin system (Yang et al, 1970 a and Yang et al, 1970 b), therefore, being, responsible by hydrolysis of the Phe 8 -His 9 bond of the AI molecule. One of the features of such enzyme is that it is inhibited by potentiator peptides of BK (BPP), described by Ferreira (1965), and Ferreira (1966).
[0022] It was also described in other animal species enzymes with similar specificity to those kininases I e II from human plasma (Erdös and Yang, 1970).
Lung
[0023] Great importance has been attributed to lung in which concerns BK elimination; many papers published by the literature describes the inactivation by this organ, regarding the high percentage of BK infused (Ferreira and Vane, 1967; Biron, 1968 and Dorer et al, 1974).
[0024] The kininase II has been already purified in hog lung (Dorer et al, 1972 and Nakajima et al, 1973) rabbit lung and rat lung (Soffer et al, 1974 and Lanzillo and Fanburg, 1974).
[0025] Studies of Ryan et al have contributed to clarify the mechanism of inactivation of this organ. BK would be inactivated, while AI would be converted into All during the circulation, by an enzyme kininase II type that was in the pynocitotic vesicles of the vascular endothelium. Ryan et al, also observed that BK is much more easily hydrolyzed than LBK-BK and MLBK. Their theory is that these bigger kinins have a more difficult access to the vesicles. According to Ryan et al statement the BK hydrolysis products which were found after the lung circulation would be consequence not only from the action of the first cited enzyme but also from the action of other enzymes contained in the cytoplasm of endothelial cells (Ryan et al, 1968 and Ryan et al, 1975).
Liver:
[0026] Erdos and Yang attributed almost exclusively to the plasmatic and pulmonary kininases the responsibility for the kinin catabolism “in vivo”. Researches carried out by Prado et al (1975) show, however, that other organs are able to inactivate kinins when they are perfused in weak rats, in which lung circulation was excluded from the perfusion circuit. In the referred paper when liver is perfused “in situ”, it was shown that the organ inactivates considerable quantity of BK.
[0027] Following these researches, Borges et al (1976) observed that BK inactivation by the perfused liver “in situ” is due to, at least, two enzymes: a peptidyl dipeptide hydrolase and a second one that hydrolyzes the Phe 5 -Ser 6 bond of BK. This enzyme could be a membrane peptidase, since it was removed from the perfused liver through the use of Triton X-100 in the perfusion liquid. According to the authors, the kinin activity obtained in this research is, very low when compared to those found in the supernatant of the total homogenate of the organ.
[0028] Mazzacoratti (1978) have worked with a preparation of this type, that is, homogenized liver from rats. It was purified two serine-proteases having different molecular weight which hydrolisates the Phe 5 -Ser 6 bond of BK.
Brain
[0029] It has been studied by many researchers the metabolism of kinins in brain extracts (Iwata et al, 1969; Camargo et al, 1969).
[0030] Kininases from homogenized rabbit brain have been systematically studied by Camargo et al (1973), Oliveira et al (1976). Two thiol-endopeptidases optimum pH 7.5 were purified from the supernatant fraction. The first enzyme, kininase A, hydrolyzes the Phe 5 -Ser 6 BK bond and has a molecular weight of 71 kDa; while the other, kininase B, hydrolysates Pro 7 -Phe 8 as kininase II, but it has a molecular weight of 6900. This enzyme would be different from the converting enzyme (kininase II), since preliminary studies did not show the conversion of AI into AII.
[0031] Wilk, Pierce and Orlowiski (1979) described two enzymes from brain tissue which differs from the referred above. One of the enzymes, which was extracted from the bovine pituitary, also hydrolysates the Phe 5 -Ser 6 Bk bond, however because of its molecular weight (higher than 100000) and because it is inhibited by Na + and K + it differs from kininase A. The second enzyme described, which was extracted from rabbit brain, is specifically for hydrolysis of those peptide bonds in which proline contributes with carboxyl group. This enzyme firstly hydrolyses the Pro 7 -Phe 8 BK bond and secondly, the Pro 3 -Gly 4 bond.
Kidney:
[0032] The kininase activity of kidney is higher than found in plasma or liver (Erdös and Yang, 1970).
[0033] Several enzymes have been purified, in this organ, with kininase activities. Researches of Erdos et al, have identified three different enzymes in the kidney: one, carboxypeptidase type, which releases arginine C-terminal of BK, which differs from some properties of plasmatic kininase I, this is why it was called kininase p (Erd ös and Yang, 1966); another enzyme, which hydrolisates the Pro 7 -Phe 8 bond (Erdös and Yang, 1967), and a third one, characterized as an imidopeptidase, which inactivates BK by hydrolysis of the Arg 1 -Pro 2 bond (Erdös e Yang, 1966).
[0034] Koida and Walter (1976) purified, from sheep kidney, an enzyme that hydrolysates Pro-x bonds type in the molecule of several peptides, among which the BK. It was observed that the x aminoacid cannot be proline and that its catalysis is faster if x is a lipophilic aminoacid.
[0035] The kinin catabolism by the kidney has been studied by methods aiming at to identify the inactivation sites of such peptides. These studies indicate that, besides the BK hydrolysis that occurs at vascular network level, the catabolism of kinins by enzymes located at renal cortical cells seems to have great importance (Erdös and Yang, 1967).
[0036] The kininase activity is very low in the glomerulus, but a type II kininase is found in great concentration in brush border of the proximal convoluted tubule (Holl et al, 1976, Casarini et al, 1997). In agreement with this discovery, Oparil et al (1976) observed that a high percentage of BK microinfused is inactivated in the proximal tubule. Considering that the kinin generation in kidneys should occur close to the distal tubule, where kallikrein is synthesized (Ørstavik et al, 1976), it seems to be logical to suppose that from this point, other kininases should be present and the nephron or in the intratubular fluid.
Urine
[0037] A carboxypeptidase was well characterized by Erdös et al (1978), in human urine; it releases BK C-terminal arginine and differs from the plasmatic one as to molecular weight, inhibitors action and immunological proprieties. However, kinetic and inhibition similarities to renal enzyme are shown.
[0038] Ryan et al described, in 1978, three enzymes contained in urine: one enzyme hydrolyzates the Pro 7 -Phe 8 BK bond and transform AI into AII; another enzyme, having 63 kDa molecular weight, which breaks the Phe 8 -Arg 9 BK bond, is not inhibited by BPP 9a .
[0039] Figueiredo et al (1978) also described, a kininase having molecular weight of 250 kDa, which is inhibited by chelate agents that would be similar to the third among those described by Ryan. This enzyme hydrolysates C-terminal arginine, although it does nor hydrolysates the HLA synthetic substrate.
[0040] With the exception of Erd ös et al, 1978, research that have purified and characterized a carboxypeptidase from urine, all researches, however, the described enzymes were only partially purified and/or characterized. Due to these contradictory data, the present invention aims at to characterize the different kininase activities that are the ACE in human urine.
[0041] One of the forms of low molecular weight (LMW) of the angiotensin I converting enzyme of 91 kDa was observed during the preparation of such enzyme from rat lung homogenate [Lanzillo et al, 1977]. This LMW form from ACE was also observed in human lung [Nishimura et al, 1978], hog kidney [Nagamatsu et al 1980] and human kidney [Takada et al, 1981]. Iwata et al (1983) and Yotsumoto at al (1983) have shown that ACE LMW of 86-90 kDa can be obtained from rabbit lung and human plasma, respectively, after treatment with bases. In the 90′ Lantz et al (1991), described three different ACE isoforms having molecular weights of 150 kDa, 80 kDa and 40 kDa characterized in the human cerebrospinal fluid. All the previously referred are similar to somatics. Casarini et al, 1991, 1995, 2001, described the 65 kDa and 90 kDa isoforms, both N-domain in hypertense patients urine and 65 kDa on normal persons. Deddish et al (1994) purified an ECA with 108 kDa molecular weight in ileal fluid, which is also an N-domain isoform of ACE.
[0042] It has been described the purification of several isoforms of ACE [Ryan et al, 1978; Kokubo et al, 1978; Skidgel at al, 1987; Casarini et al, 1983, 1987]. Kokubo at al (1978) found three different forms of ACE normal human urine. Two forms with high molecular weight of >400 kDa and 290 kDa and a third one, molecular weight of 140 kDa. Ryan et al (1978) described a kininase II human urine that was separated in two forms. The first co-cromatography with somatic ACE of 170 kDa, and the second was similar to a protein having molecular weight of 90 kDa. Casarini et al (1983, 1991, 1992, 1995, 2001) described he ACE in human urine of normal persons and hypertense patients with molecular weights of 190 kDa, 90 kDa and 65 kDa and also in rat urine (Casarini et al 1987). Alves et al, 1992 also described isoforms of 170 kDa, 90 kDa and 65 kDa in urine of normal persons and hypertense patients. Costa et al, 1993, 2000 described in normal persons urine, ACE with different molecular weights of 170 kDa, 65 kDa and 59 kDa, and in the hypertense patients, renovasculares enzymes with molecular mass of 55 kDa, 57 kDa e 94 kDa. The ACE activity in urine is not from the plasma but from the renal tubule (Casarini et al, 1997) and can be used as a reference for the renal tubular damage, since there is a considerable level increasing in renal and infections of upper urinary treat diseases [Baggio et al, 1981; Kato et al, 1982].
[0043] It was also recently described, two ACE isoforms in intracellular and extracellular medium of mesangial cells in culture, having molecular weight of 130 kDa and 65 kDa (Andrade et al, 1998). It was still observed the presence of 190 kDa and 65 kDa isoforms in children urine but in premature children only 65 kDa isoforms ACE, being the latter similar to the N-domain portion of the same. In premature children, it was found, in a period of 1 to 30 days after they were born, that these 190 kDa isoform would appear only in the thirtieth day (Hattori et al, 2000).
BRIEF DESCRIPTION OF DRAWINGS
[0044] FIG. 1 (A, B, C): Shows a gel Chromatography filtration in Ac A-34 column of human urine.
[0045] FIG. 1A : Normotensive children/normotensive parents (At 280 nm-ACE Activity on the HHL substrate).
[0046] FIG. 1B : Normotensive children/hypertensive parents (At 280 nm-ACE Activity on the HHL substrate).
[0047] FIG. 1C : Hypertensive children/hypertensive parents (At 280 nm-ACE Activity on the HHL substrate).
[0048] Urine of normotensive persons with hypertensive parents has presented the three ACE isoforms having 190 kDa, 90 kDa e 65 kDa molecular weights, showing that the 90 kDa premature isoform appears. Thus, showing to be a prognostic that these persons (individuals) could get hypertension, being, therefore, a genetic marker for hypertension.
[0049] FIGS. 2A and 2B : Presentation of N-terminal and C-terminal sequence of 90 kDa and 65 kDa angiotensin I isoforms converting enzymes. The 65 kDa enzyme ends at the number 481 aminoacid. The 90 kDa enzyme ends at number 632 aminoacid.
[0050] FIG. 3 : Fresh human urine Western Blotting—Line 1: normal person urine, Line 2: wild ACE recombinant, Line 3: ACE recombinant secreted, Line 4: hypertensive patient urine.
[0051] FIG. 4 : Scheme of dosage by mass spectrometer—the scheme presents 5 (five) steps which starts by raw urine that in the second step is centrifuged for 10 minutes at 3000 rpm speed and at 4° C. temperature. In the third step, urine is concentrated 4× (four times) in a Ultrafree (Millipore) tube and is centrifuged during 5 (five) minutes at 3000 rpm and 4° C., then going to a forth step where concentrated urine pass through a dialysis in centricon Tris/HCL 1 mM buffer, pH 8.0 centrifuged during 5 (five) minutes at 3000 rpm and 4° C., resulting in a concentrated urine and dialyzed and finally, the fifth step which results the HPLC-MS.
DESCRIPTION OF THE INVENTION
[0052] In order to carry out the method of identification and quantification of proteins, isoforms of the angiotensin I converting enzyme, specifically 190-kDa ACEs, specially 90 kDa and 65 kDa in tissues, cells and biological fluids, specially in urine, according to the present invention, it starts with collecting fluids, such as urine, tissues or cells from living organisms, submit them to a chromatographic separation (AcA44 and/or AcA 34 resin; reverse phase column C-18, in mass spectrometer) and by Western Blotting (using a specific antibody against somatic ACE and N-domain ACE [90 kDa, genetic marker for hypertension and 65 kDa] of 190 kDa, 90 kDa and 65 kDa isoforms. Normal individuals have the 190 kDa and 65 kDa isoforms while the 90 kDa isoform (hypertension genetic marker) will characterize those individual predisposed to develop hypertension and lesion in characteristic target organs (heart, nervous system, vascular system and kidney).
[0053] The method of the present invention considers that an aliquot of fluid (for example, fresh or concentrated urine), cells and tissues are processed and analyzed by high performance liquid chromatography and detection by mass spectrometry (HPLC-MS) or directly in the mass detector, where the sample is analyzed and compared with the previously established standards for 190 kDa, 90 kDa (hypertension genetic marker) and 65 kDa ACE isoforms. An aliquot of fluid (for example, fresh or concentrated urine), cells and tissue are processed and analyzed by Western Blotting or another immunoprecipitation method) using specific antibodies against 190 kDa and N-domain ACE (90 kDa hypertension genetic marker and 65 kDa), using as a control analysis the ACE isoforms prepared as standards as well as the ECA recombinant enzyme.
[0054] In order to reach the results proposed by the present invention, the researches on ACE, started in 1983, when essential (light and/or mild forms) arterial hypertensive patients were analyzed after using captopril (50 to 150 mg) orally administered in one-day dose. Three days study, each day, each six hours collect duration; samples of blood and urine were collected at the final basal period (1 hour), after they reach the supine position, as well as at the end of the study (after 6 hours). The results show a 50% inhibition on the enzyme activity, in a period between 1 and 2 hours after captopril administration, returning to the basal levels at the end of the studies. The enzymatic activity using Hipuril-His-Leu substrate was measured by Friedland and Silverstein method (1976). Through ion exchange chromatography analysis, the collected urine (collected after 6 hour) two protein peaks were eluted with angiotensin I converting activity and inactivated for bradykinin, in conductivity of 0.7 mS (90 kDa) and 1.25 mS (65 kDa), differing from the profile found in 190 kDa e 65 kDa ACE in normotensive individuals. Based on this, studies have been developed with a higher number of light hypertensive patients, where it was found the presence of two protein peaks with angiotensin I converting activity, as cited above (Casarini et al, 1991).
[0055] Following the studies as referred above (project support by FAPESP, No 95/9168-1) the following study groups were organized: normal parents/normal children; normal parents/hypertensive children; hypertensive parents/hypertensive children and hypertensive parents/normal children. It was found that the group (normal parents/hypertensive children) hypertensive parents/hypertensive children, the children urine was presented two 90 e 65 kDa forms; in the normal parents/normal children group, the children urine presented the 190 and 65 kDa forms; and, finally, in the hypertensive parents/normal children, the children urine presented the 190, 90 and 65 kDa forms, being these two last forms, N-domain fragments.
[0056] From these results, it was concluded that 90 kDa would possibly be a hypertension marker. In order to prove if this findings was a genetic factor or another fact related or not to pressure increasing (physical), data were validated in the same project in the experimental model for rats. For this purpose, it was studied Wistar Brown Norway, Lyon, SHR, 1R1C and DOCA-salt rats urine. As a result, the Wistar, DOCA-salt, 1R1C and Brown Norway rats presented 170 and 65 kDa forms; only SHR and SHR-SP rats presented the 90 and 65 kDa forms. These results confirm those obtained for humans, thus, being, the 90 kDa ACE isoform a hypertensive genetic marker (Fapesp 97/00198-0, Marques 1999).
[0057] In 1997, researchers of the present invention described that the mesangial cells in a culture that expresses the ACE RNAm (Casarini et al, 1997). This enzyme is detected in the intracellular (136 kDa and 65 kDa) and secreted (136 kDa e 65 kDa), indicating a potential effect of the local production of angiotensin II in the function of these cells (Fapesp 95/9168-1; Andrade et al, 1998).
[0058] It was observed latter that the intracellular and the culture means of the SHR mesangial cells presented the same profile of (90 and 65 kDa) ACE isoforms, which were found in urine of such rats (Fapesp 99/01531-1); therefore, this confirms the results of the previous researches. From these results, it was observed by the authors of the present invention, that these isoforms are expressed in the lung, adrenal, heart, aorta and liver of Wistar rats (136 kDa and 69 kDa) and SHR (96 kDa and 69 kDa) and are not restricted to kidney (Ronchi, 2002); emphasizing that the 80/90/96 kDa hypertension genetic marker is expressed in the various tissues and, therefore, bringing to conclude that these isoforms can contribute for a regulation of the specific organ (it should be stressed that when de 80 or 96 or 90 kDa enzymes are referred, it should be understood, the same enzymes with small alteration in the glycolization process).
[0059] The present invention starts with fluid collect as for example urine, tissue or living organisms cells, that are submitted to a chromatographic separation (resin AcA44 and/or AcA 34; phase reverse column C-18, mass spectrometer) and by Western Blotting (using a specific antibody against ACE somatic and against ACE N-domain [90 kDa, hypertension genetic marker and 65 kDa] of 190 kDa, 90 kDa and 65 kDa isoforms. The 190 kDa and 65 kDa isoforms will be present normal individuals (normal rats, cells and/or tissue from normal rats); while the 90 kDa (hypertension genetic marker) isoform will characterize those (individuals or animals, etc) predisposed to develop hypertension and lesions in characteristics target organs (heart, nervous system, vascular system and kidney). A aliquot of fluid (for example, fresh or concentrated urine), cells and tissue are processed and analyzed by high performance liquid chromatography method and detection by using mass spectrometry (HPLC-MS) or directly in the mass detector, where the sample is compared with the standards established for ACE of isoforms 190 kDa, 90 kDa (hypertension genetic markers) and 65 kDa. An aliquot of fluid (for example, fresh or concentrated urine), cells and tissue are processed and analyzed by Western Blotting using specific antibodies against 190 kDa ACE and N-domain ACEs (90 kDa), hypertension genetic marker and 65 kDa), using as analysis control the ACE isoforms prepared as standards and the recombinant ACE enzyme.
ACE Isoform as Hypertension Marker
[0060] Isoform of Angiotensin I Converting Enzyme (90 kDa, N-Domain) as a Hypertension Genetic Marker Produced by Human Urine:
[0061] Based on the previous studies, the researchers of the present invention found in normotensive individuals urine and using ion exchange chromatography, two peaks of angiotensin I converting activity with molecular mass of 190 kDa and 65 kDa. When hypertension patients urine is processed, it was obtained a profile where two peaks were eluted with angiostensin I converting activity in the 90 kDa and of 65 kDa molecular weight, not being detected the 190 kDa form (Hypertension 26:1145-1148, 1995).
[0062] One of the objectives of the present invention consists in confirming the potential of the de 90 kDa isoform as a hypertension genetic marker and as a hypertension prognostic.
[0063] The following study groups were established for this purpose:
normotensive individuals with normotensive parents, normotensive with hypertensive parents, hypertensive with normotensive parents, and hypertensive with hypertensive parents.
[0068] The collected urines were concentrated separately and dialyzed with Tris-HCl 50 mM buffer, pH 8.0 and then submitted gel filtration in AcA-34 column equilibrated with Tris-HCl 50 mM buffer, containing NaCl 150 mM, pH 8.0. The collected fraction (2 mL) have been monitored by reading the absorbance in 280 nm and by the angiotensin I converting activity, using Hipuril-L-His-L-Leu- and Z-Phe-His-Leu as substrates. The following results was obtained: normotensive individuals with normotensive parents presented two isoforms with ACE activity (190 kDa and 65 kDa) (n=21); normotensive individuals with hypertensive parents presented three (190 kDa, 90 kDa and 65 kDa) (n=13) isoforms and hypertensive individuals with hypertensive parents presented two isoforms (90 kDa and 65 kDa) (n=13). As expected, it was not found anybody that would constitute the hypertensive group with normotensive parents.
[0069] Two individuals that presented 190 kDa, 90 kDa and 65 kDa isoforms, normal pressure, and that were in contact with the research group, were monitored for 4 years. In the forth year after detection of isoforms in the urine, they became hypertensive; this proves, therefore, that the 90 kDa isoform is really a hypertensive genetic marker.
CONCLUSION
[0070] Considering that the urine of normotensive individuals with hypertensive parents presented the three ACE isoforms with molecular weight of 190 kDa, 90 kDa and 65 kDa, shows that the 90 kDa isoform which early appears, is a prognostic that these individuals could be a hypertensive person, thus, being, a hypertensive genetic marker.
Quantification and Identification of the ACE Isoform, Hypertension Genetic Marker by Mass Espectrometry and Western Blotting
Western Blotting of the Human Fresh Urine:
[0071] Urine was collected from a single time in the presence of a “pool” (several inhibitors) of proteases, then, it was concentrated and 100 ug was submitted to a 7.5% polyacrylamide gel electrophoresis, followed by Western Blotting with PVDF membrane, then it was incubated with the polyclonal antibody Y1 against human ACE. Line 1: urine of normal individual, Line 2: ACE wild recombinant, Line 3: ACE recombinant secreted, Line 4: hypertensive individual urine.
Dosage for Mass Espectrometer:
[0072] Raw urine was centrifuged for 10 minutes, at 3000 rpm, 4° C., followed by 4× concentration in Ultrafree (Millipore) tube, then centrifuged for 5 minutes at 3000 rpm, 4° C., dialyzed with centricon Tris/HCl 1 mM buffer, pH 8.0. Then, it is centrifuged for 5 minutes, at 3000 rpm, 4° C. Concentrated and dialyzed urine was, then, obtained and therefore, the prepared sample was analyzed in HPLC-MS.
[0073] The solvents used in the HPLC system were: solvent A, which consists of 0.1% trifluoroacetic acid (TFA, Merck, Germany). The urines were separated in a Nova Pak C 18 (Waters) reverse phase column, for 15 minutes with a 1.5 mL/min flux. The conditions are still been standardized in order to improve the method resolution.
[0000] Isoform of Angiotensin I Converting Enzyme (90 kDa) as a Hypertensive Genetic Marker Secreted in Rats Urine. Protocol Design to Prove the Findings (Affirmation of Genetic Marker for the 90 kDa Protein) with Human Urine.
[0074] ECA isoforms presented in isogenic normotensive rats (WKY and Brown Norway) urine have been identified as well as in normotensive, isogenic hypertensive (SHR, SHR-SP, Lyon), isogenic normotensive, experimentally hypertensive (1K1C and DOCA-Salt) and isogenic hypertensive rats, which were treated with antihypertensives drugs (SHR+enalapril), aiming at to compare the obtained chromatography profiles, and with the objective to characterize the 90 kDa form as an arterial hypertensive genetic marker.
[0075] From WKY rats urine, two peaks of AI converting activity have been separated by gel filtration in AcA-44 resin: the first, WK-1, corresponds to a high molecular enzyme (190 kDa) and the second one, WK-2, corresponds to a low molecular weight (65 kDa); these data were confirmed by Western Blotting. In the SRH group, the chromatographic profile have presented different results from the previous group (WK), being identified an ACE called S-1, with molecular weight 80 kDa, and a second one, S-2, molecular weight of 65 kDa, similar to those found in hypertensive patients urine that was not 90 kDa and 65 kDa treated (Casarini et al., 1991). The molecular mass differences between the 80 kDa enzyme from rat and the 90 kDa enzyme of human urine occur due to the glycolization process (data not shown).
[0076] In the third group (1K1C), a renovascular induced hypertension model, the chromatography profile was similar to the one found in rats used as control (WKY). In this group two peaks of AI converting activity were obtained: the first, C-1, corresponds to a 190 kDa enzyme and the second one, C-2, to 65 kDa.
[0077] Two peaks of AI converting activity were separated by gel filtration in AcA-44 resin, from SHR-SP rats urine: the first one, called SP-1, corresponds to a 80 kDa enzyme and a second one, called SP-2, which corresponds to the 65 kDa enzyme, similar to that found in SHR rats urine and also found in not-treated hypertensive patients urine (Casarini et al, 1991, 1995).
[0078] On the other hand, the SHR rats, which were treated with enalapril, show that although having their pressure under control, they carry the 80 kDa isoform; this fact shows that the isoform profile is linked to genetic factors.
[0079] In the group of rats used as control, the DOCA-Salt model, in which it was not administered the hypertensive treatment, the chromatographic profile was similar to that found for normotensive WK rats. Two peaks with AI converting activity were obtained: the first, CD-1, corresponds to a 190 kDa enzyme, and the second, CD-2, corresponds to the 65 kDa.
[0080] The DOCA-Salt model, with reduced hypertension induced by DOCA and saline administration, presented a chromatographic profile similar to that found in DOCA-Salt and WK control rats. Two peaks of AI converting activity were obtained: the first one, D-1, corresponds to 190 kDa ECA, and the second one, D-2, to 65 kDa ECA. This result shows that the 80 kDa presence is linked to a genetic factor not being consequence of the increasing of pressure.
[0081] The result of the gel filtration in Brown Norway normotensive rats urine was similar to the profiles found in normotensive rats urine. Two peaks with ACE activity have been obtained: BN-1, which corresponds to the 190 kDa enzyme, and the second one, BN-2, which corresponds to the kDa enzyme, showing that different strain of normotensive presents the same chromatographic profile.
[0082] Comparing the chromatographic profiles of WK rats (normal control) urine, 1K1C (experimental hypertensive-Goldblatt), DOCA-Salt (control), DOCA-Salt (experimental hypertensive) and normotensive Brown Norway with the urine of SHR rats, Lyon and SHR-SP (genetically hypertensive), it can be affirmed that the basic difference is the presence de 80 kDa isoforms in the genetically hypertensive rats urine. The fact that the 80 kDa isoform do nor appear in the 1K1C and DOCA-Salt rats, whose hypertension is induced (physical factor), reinforces the hypothesis that the same is linked to a genetic factor.
CONCLUSION
[0083] The results found suggest that rats, genetically predisposed to hypertension, the 80 kDa form would be detected instead of 190 kDa; this would be used to, as a consequence, as an early genetic marker for hypertension.
[0000] Segregation of the Isoform of Angiotensin I Converting Enzyme (90 kDa, N-Domain), Hypertension Genetic Marker in Rat Urine. Protocol Design to Show the Presence (Segregation of the Hypertension Genetic Marker (Protein of 90 kDa) in Rats Urine. Rats Crossing Expontaneously Hypertenses (SHR) and Brown Norway (BN).
[0084] In a previous project it was characterized the different isoforms of low molecular weight in rats urine in different experimental models (Wistar-Kyoto, SHR, 1R1C, DOCA-salt control, DOCA-salt, SHR-SP and Brown Norway). It was observed that the 90 kDa form only appears in SHR and SHR-SP rats, showing a genetic factor for the presence of such a form. In this project, it is studied the isoforms gene transmission of 190 kDa, 80 kDa and 65 kDa of the angiotensin I converting enzyme, genotype and phenotype analysis in rats urine generated from the crossings and backcrossings among SHR and Brown Norway races.
Drawing of the Crossing
[0085] Crossings were carried out between Brown Norway and SHR (BN×SHR), rats generating a group of heterozygotes rats called F1SB01 to F1SB04; from this group two animals were chosen (F1SB01 e F1SB03), males in order to carry out the backcrossing with the SHR rat (female). For phenotyping, the urine of the animals was collected and concentrated, then, it was submitted to a AcA-34 gel filtration column chromatography, together with Tris/HCl 0.05M buffer, pH 8.0, containing NaCl 0.15M. Fractions of 2.0 ml have been eluted under a 20 ml/h flux, being monitored by absorbance measured in A280 nm and by the ACE enzymatic activity using Z-Phe-His-Leu (ZPheHL) as a substrate.
Results
[0086] Parents: two peaks with ACE activity were eluted from BN rats urine and submitted to AcA-44, BN-1 e BN-2 column chromatography, with molecular weight estimated of 190 kDa and 65 kDa, respectively. On the other hand, in SHR rats urine it was found two peaks with converting activity, however, with molecular weight estimated of 90 kDa and 65 kDa, respectively.
[0087] In F1, 39 animals were generated, from which 100% were phenotyped as heterozygotes for the three, 190, 90 and 65 kDa enzyme forms. From the backcrossing animals were generated from which 85% present the three enzyme isoforms (NH group) and 15% presented the 90 and 65 kDa forms (H group).
CONCLUSION
[0088] Through the obtained results, it is suggested that the kDa isoforms (arterial hypertension genetic marker) continue to be present in the generations originated by the crossings and backcrossings.
[0000] Expression of the Hypertension Genetic Marker, 90 kDa Isoforms in Tissues (Aorta, Adrenal, Heart, Liver, Lung, Kidney, Pancreas) of Rats Expontaneously Hypertensives Compared with to the Wistar and Isogenic Wistar.
[0089] It as been identified in previous studies 190 and 65 kDa in Wistar, whose profile, similar to those described for normotensive individuals. 80 and 65 kDa isoforms have been identified in SHR rats urine while N-terminal ECA fragments repeats the profile, which was found for light hypertensive individuals.
[0090] The homogenates were submitted to a gel filtration chromatography and two peaks have been detected, having activity on the HHL substrate in different W and W1 rats tissue, whose molecular weights of 137 and 69 kDa are similar to those referred for W rats (Table I). The SHR rats tissues also presents two peaks of activity whose estimate molecular weights are 96 e 69 kDa, and this profile corresponded to the one found for the enzymes contained in the urine of said rats. The protein expression of the 137 and 69 kDa isoforms was observed in all tissues, which have been studied, obtained from Wistar and isogenic Wistar rats through the Western Blotting technique. By using the same technique, 96 and 69 kDa isoforms expression of all tissues of the SHR rats have been confirmed (Table I). The obtained results show the expression of the 69 kDa isoforms (besides the 137 kDa isoforms) in the W and WI tissues, as the 96 and 69 kDa isoforms in SHR rats tissues, bringing to the conclusion that the expression of N-domain isoforms, more specifically the 96 kDa isoform (hypertensive genetic marker) is not restricted only to urine and/or kidney, but are also present, locally, in the studied tissues.
[0000]
TABLE I
Sumary of the study as to elution fractions and
estimated molecular masses, showing the 80 kDa ECA as
hypertension genetic marker.
Estimated
Elution
Molecular Weight
Strains
Enzymes
Fraction (N o )
(kDa)
WKY
WK-1
32
190
WK-2
54
65
SHR
S-1
50
80
S-2
55
65
1K1C
C-1
32
140
C-2
54
65
DOCA-Salt
D-1
34
190
D-2
52
65
DOCA-Salt
CD-1
34
190
Control
CD-2
52
65
SHR-SP
SP-1
50
90
SP-2
55
65
BN
BN-1
32
190
BN-2
54
65
SHR
S-1
50
80
enalapril
S-2
55
65
Lyon
L-1
50
80
L-2
55
65
Expression of the Hypertension Genetic Marker, 90 kDa Isoforms in the Mesangial Cells in Rats Culture, Expontaneously Hypertensesives Compared to the Wistar Rats
[0091] The glomerulus has been isolated from Wistar or SHR rats, according to Greenspon and Krakomer method (1950). The rats were put under sulfuric ether atmosphere and submitted to a bilateral nefrectomy. Kidneys were decapsulated and cortical macrodissecation was carried out. The cortex was separated from the medula and then, fragments were passed through series of sieves which differ in size according to the meshes openings (60, 100 and 200 mesh). The glomerulus were collected from the surface of the third sieve and forced to pass through a (25×7) needle (aiming at to decapsulate the glomerulus. The decapsulated glomerulus were counted by using Newbauer chamber and divided (density of −300 glomerulus/cm 2 ) in 25 cm 2 bottles, using RPMI 1640 supplemented with 20% of bovine fetal serum, penicillin (50 U/mL), HEPES (2.6 g) and glutamin 2 mM. The culture bottles were maintained into CO 2 (5%), at 37° C. Each 36 h the medium was changed. After 3 weeks approximately the primary culture of the mesangial cells were submitted to trypsin. The subcultures grew in the same medium. This procedure was repeated up to the third subcultured, when cells were prepared for the experiments: Mesangial cells (MC) (3° subcultured) were incubated for 20 hours with RPMI, without bovine fetal serum; further, the MC and the medium was collected separately.
[0092] The collected mean in the 3° subcultured was concentrated in an Amicon concentrator. The concentrated medium (2.0 mL) was submitted to a gel filtration in AcA-44 (1.5×100.8 cm column; volume 178.0 mL), equilibrated with Tris-HCl 50 mM buffer, pH 8.0, containing NaCl 150 mM. Fractions of 2.0 mL under flux of 20 mL/h were collected. Elution was carried out under a 20 mL flux by one hour. Fractions of 2 mL were collected, and monitored by absorbance measurements in 280 nm and the enzymatic activity was quantified, by using Hippuryl-His-Leu (HHL).
[0093] The CM collected were lysed with 4 mL Tris-HCl 50 mM buffer, pH 8.0, containing Triton X-114 1% and PMFS 0.5 mM, through mechanical agitation, by one hour, at 4° C. After this period, the lysed cells were centrifuged and the supernatant was collected and concentrated an Amicon concentrator, under nitrogen pressure, at 3 kgf/cm 2 . Further, 2 mL was submitted to a gel filtration chromatography.
[0094] The results obtained for MC in Wistar and SHR rats culture presented the same chromatographic profile obtained for human urine of normal individuals and moderated hypertension patients as well as for urine of Wistar and SHR rats, thus, confirming that in kidneys, more specifically in the glomerulus, the different isoforms, already mentioned, are produced (Table II).
[0000]
TABLE II
Summary of the study groups as to determinate
molecular masses.
Wistar
Tissues
Wistar
Isogenic
SHR
Adrenal
137
137
96
69
69
69
Aorta
137
137
96
69
69
69
Heart
137
137
96
69
69
69
Liver
137
137
96
69
69
69
Lung
137
137
96
69
69
69
Kidney
137
137
96
69
69
69
Testicle
137
137
96
69
69
69
FINAL CONCLUSION
[0095] Based on the fact that 90 kDa ACE only appears in hypertensive patients/MC of SHR/urine of SHR rats, it is suggested that it could have an important and specific role as a hypertension genetic marker.
[0096] Based on the studies obtained with the parents and children there was observed that 190, 90 e 65 kDa isoforms are present in normal individuals from hypertensive parents showing that a segregation of this isoform, thus, it could be characterized as a hypertensive predictor. These data were confirmed in crossing and backcrossing of Brown Norway and SHR rats (Table III).
[0000]
TABLE III
ECA isoforms detected in the extracellular and
lysed cells mesangial cells in Wistar and SHR rats culture.
Rats
Extracelular
Intracelular
Wistar
130 kDa
135 kDa
60 kDa
68 kDa
SHR
80 kDa
80 kDa
60 kDa
68 kDa
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[0000]
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BACKGROUND OF THE INVENTION
The present invention relates to nuclear reactors and, more particularly, to tools for removing and installing control rod drives for commercial power nuclear reactors.
A boiling-water nuclear reactor employs a plurality of fuel rods containing a nuclear fuel within a reactor vessel. The reactor vessel is filled with water to a level at least sufficient to cover the fuel rods. Fission in the fuel rods releases heat that boils the water surrounding them. This steam is used, either directly, or through an intermediate heat exchanger, to perform a useful function such as, for example, driving an electric turbine-generator.
The intensity of the nuclear reaction in a nuclear reactor is controlled, in part, by moving control rods between fuel rods. The control rods absorb neutrons, thereby controlling the intensity of the nuclear reaction, and the rate at which steam is produced.
The control rods are controlled by control rod drives inserted through the bottom of the reactor vessel. Control rod drives occasionally require maintenance or replacement. This has presented a problem because of the structure of the control rod drives and the working environment in which they must be handled.
A typical control rod drive is about 16 feet long and weighs about 450 pounds. It is thus an awkward device that requires substantial mechanical handling assistance to install and remove. In addition, the sub-pile room below the reactor vessel typically has a headroom between the floor and the bottom of the reactor vessel of about 18 feet. This leaves little maneuvering room for lowering the control rod drive, rotating it into a horizontal position, and moving it out of the sub-pile room. Also, numerous fragile instrumentation cables hang down from the bottom of the reactor vessel. Such instrumentation cables can be damaged by contact with a control rod drive. If an instrumentation cable is damaged, the rules governing operation of a nuclear reactor require that work must stop until the damaged instrumentation cable is repaired.
A further problem arises because the sub-pile room below a nuclear reactor is a high-radiation area. It is thus desirable to limit the amount of time that workers spend in that area.
The following publications relate to devices which are used to lower and rotate a control rod drive in the sub-pile room. All of these publications are in Japanese, and full translations are not available. A translation of claim 1 is available and is provided for the use of the Patent and Trademark Office:
Japanese Patent Publication No. 60-48715
Japanese Patent Publication No. SHO-60-49277
Japanese Patent Publication No. SHO-61-31839
Japanese Patent Publication No. 58-32359
Japanese Patent Publication No. SHO-61-36636
Japanese Patent Publication No. 61-42838
Japanese Patent Publication No. SHO-61-42839
Japanese Patent Publication No. SHO-61-36635
Japanese Patent Publication No. SHO-61-33158
Japanese Patent Publication No. SHO-61-25116
Japanese Patent Publication No. SHO-61-13198
Japanese Patent Publication No. SHO-57-39398
Japanese Patent Publication No. 57-49833
Japanese Patent Publication No. SHO-58-27880
Japanese Patent Publication No. 59-31034
Japanese Patent Publication No. SHO-60-35035
Japanese Patent Publication No. SHO-60-35036
Japanese Patent Publication No. 60-37439
Japanese Patent Publication No. SHO-60-46676
The length of the above list is regretted. However, the spirit of full disclosure requires the inclusion of each reference of which the applicants are aware.
Also, as the seal between a control rod drive and the reactor vessel is broken during removal, a small amount of residual water spills from in the reactor vessel. Usually, the spilling water, which is contaminated with radioactivity, falls upon a worker in the process of removing the control rod drive. Although workers wear protective clothing and breathing apparatus in this area, it is considered undesirable to permit residual water to fall upon them. Japanese Utility Model Application Publication No. 57-49834, and Japanese Patent Publication Nos. SHO-58-15759 and SHO-53-18676 disclose water drain apparatus for use with control rod drives.
Bolts securing a control rod drive are highly torqued during installation. Due to the cramped conditions in the sub-pile room, it is difficult to maneuver suitable tools into place to detorque these bolts to enable their removal. Japanese Patent Publication Nos. SHO-61-22274 and SHO-61-22275 disclose tools designed to remove such bolts.
OBJECTS AND SUMMARY OF THE INVENTION
It is an object of the invention to provide tools for handling control rod drives that overcome the drawbacks of the prior art.
It is a further object of the invention to provide a handling tool for a control rod drive that permits positive control of the control rod during all stages of the removal process.
It is a still further object of the invention to provide a handling tool for a control rod drive that reduces the likelihood of damaging instrumentation cables below a reactor vessel.
It is a still further object of the invention to provide a handling tool for a control rod drive that reduces the time required for removing and installing a control rod drive.
Briefly stated, the present invention provides a low-headroom tower that is pivotably mounted to a trunnion cart. The trunnion cart runs on rails in a slot in a work platform located in the sub-pile room of a reactor containment. An elevator in the tower raises an extension piece into contact with the bottom of a control rod drive. A detorquing guide is rotationally positioned to coincide with bolts holding the control rod drive in place. The elevator places an upward force on the control rod drive during detorquing of the bolts. This provides reaction torque to aid in bolt loosening and prevents leakage of contaminated effluent past the seal. A detorquing tool is fitted into the detorquing guide and is spring loaded to engage a selected bolt securing the control rod drive. An indexing device provides alignment for the detorquing tool with each succeeding bolt. The elevator is lowered until the bottom end of the control rod drive enters the tower. The load is transferred from the extension piece directly to the elevator. Lowering continues until the top end of the control rod drive emerges from the reactor vessel. A winch pivots the tower to the horizontal position about the trunnion cart, and rear wheels are engaged with the rails to permit rolling horizontal movement of the tower. An effluent container clamps around the control rod drive to channel away contaminated water that passes through the broken seal as the control rod drive experiences its first movement. A two-piece radiation shield pig is preset onto guide rods to clamp quickly onto the top end of the control rod drive.
According to an embodiment of the invention, there is provided apparatus for handling a control rod drive for a nuclear reactor, comprising: a tower positionable below the nuclear reactor, means for lowering and raising the control rod drive a substantial distance within the tower, and means for rotating the tower, containing the control rod drive, between a horizontal and a vertical position, whereby transfer of the control rod drive is enabled.
According to a feature of the invention, there is provided a method for handling a control rod drive for a nuclear reactor, comprising: positioning a tower below the nuclear reactor, lowering and raising the control rod drive a substantial distance within the tower, and rotating the tower, between a horizontal and a vertical position, whereby transfer of the control rod drive is enabled.
According to a further feature of the invention, there is provided a method for removing a control rod drive from a nuclear reactor, comprising: positioning a tower below the control rod drive, engaging an upper end of an extension piece with the control rod drive, lowering the extension piece and the control rod drive a first portion of a distance required to clear the control rod drive from the nuclear reactor, removing the extension piece, continuing lowering the control rod drive a remainder of the distance until the control rod drive is clear of the nuclear reactor, and rotating the tower, with the control rod drive therein, to a horizontal position, whereby horizontal displacement of the control rod drive is enabled.
According to a still further feature of the invention, there is provided a method for installing a control rod drive in a nuclear reactor, comprising: rolling a horizontal tower, containing the control rod drive, into position below the nuclear reactor, rotating the tower, and the control rod drive, into a substantially vertical position wherein a top end of the control rod drive is generally aligned with a predetermined point on a bottom of the nuclear reactor, raising the control rod drive a first portion of a distance required to install it in the nuclear reactor, transferring a load of the control rod drive to an extension piece, and continuing raising the control rod drive a remainder of a distance required to install it in the nuclear reactor.
According to another feature of the invention, there is provided apparatus for removing a control rod drive from a nuclear reactor, comprising: a tower, means for positioning the tower below the control rod drive, an extension piece, means for engaging an upper end of the extension piece with the control rod drive, means for lowering the extension piece and the control rod drive a first portion of a distance required to clear the control rod drive from the nuclear reactor, means for removing the extension piece, means for continuing to lower the control rod drive a remainder of the distance until the control rod drive is clear of the nuclear reactor, and means for rotating the tower, with the control rod drive therein, to a horizontal position, whereby horizontal displacement of the control rod drive is enabled.
According to still another feature of the invention, there is provided a torque breaker for breaking torque of a plurality of bolts securing a control rod drive of a nuclear reactor, the bolts being disposed in a first pattern, comprising: an extension piece, means for engaging the extension piece with a bottom of the control rod drive, a torque breaker tool, engagement means at a first end of the torque breaker tool, the engagement means being effective for rotationally engaging one of the plurality of bolts, an indexing guide affixed to the extension piece, support means at a second end of the torque breaker tool, pivoting means at a second end of the torque breaker tool, means in the indexing guide for pivotably engaging the pivoting means, the indexing guide including means for indexing to a plurality of predetermined positions about a circle, the plurality of predetermined positions being of the same number as the plurality of bolts, means for permitting rotation of the indexing guide to an angular position providing vertical alignment of one of the plurality of positions with one of the plurality of bolts, means for maintaining a fixed relationship between the indexing guide relative to the plurality of bolts, and means for permitting engagement of the engagement means with successive ones of the plurality of bolts, whereby torque of the plurality of bolts is broken.
According to a still further feature of the invention, there is provided a torque breaker for breaking a torque of a plurality of bolts in a control rod drive, the bolts being disposed in a predetermined pattern, comprising: an extension piece, means for engaging the extension piece with a bottom of the control rod drive, a torque breaker tool, an indexing guide affixed to the extension piece, the indexing guide defining a plurality of positions corresponding to the predetermined pattern, means for aligning the indexing guide in an aligned position wherein one of the plurality of positions is aligned with one of the bolts, whereby all of the plurality of positions are aligned with corresponding bolt positions, means for locking the indexing guide in the aligned position, the indexing guide including means for retaining a bottom end of the torque breaker tool at any selectable one of the plurality of positions, an engaging portion at a top end of the torque breaker tool, the engaging portion including means for engaging an aligned one of the bolts, means for exerting torque on the torque breaker tool, whereby the one of the bolts is loosened, and means for indexing the torque breaker tool to a next one of the plurality of positions, whereby a next one of the bolts may be loosened.
According to a still further feature of the invention, there is provided an effluent container for catching a burst of effluent from a nuclear reactor when a control rod drive is removed therefrom: a rod, means for moving the rod into forcible contact with a bottom of the control rod drive, the forcible contact being effective for avoiding substantial leakage of the effluent from the control rod drive, first and second halves of a water container, each of the first and second halves including a semi-cylindrical sidewall and a semi-circular bottom, each of the bottoms including a semi-circular cutout, the semi-circular cutouts being fitted together to form a circular hole generally conforming to a peripheral surface of the rod, means for conducting a liquid from the liquid container, the liquid container being fittable over a bottom of the control rod drive including a location from which effluent leakage is expected, a clamp cylinder fittable over the liquid container, the clamp cylinder being effective for holding the first and second halves of the liquid container together, and means on the clamp cylinder for permitting retention of the clamp cylinder while the liquid container is slid downward therethrough.
According to a still further feature of the invention, there is provided a radiation shield pig assembly for shielding a filter end of a control rod drive as it exits a nuclear reactor, comprising: first and second guide rods affixed below the nuclear reactor adjacent opposed sides of the control rod drive, a first hanger assembly, first means for temporarily affixing the first hanger assembly on the first guide rod, a second hanger assembly, second means for temporarily affixing the second hanger assembly on the second guide rod, a first semi-cylindrical half shield, first quick-release means for affixing the first semi-cylindrical half shield to the first hanger assembly, a second semi-cylindrical half shield, second quick-release means for affixing the second semi-cylindrical half shield to the second hanger assembly, means for clamping abutting edges of the first and second semi-cylindrical half shields to form a cylindrical radiation shield, means for clamping the cylindrical radiation shield to the control rod drive, and means for releasing the first and second semi-cylindrical half shields from the first and second hanger assemblies, whereby the cylindrical radiation shield may remain on the control rod drive during movement thereof.
According to a still further feature of the invention, there is provided a method for shielding an end of a control rod drive of a nuclear reactor, comprising: affixing first and second guide rods below the nuclear reactor adjacent opposed sides of the control rod drive, temporarily affixing a first hanger assembly on the first guide rod, temporarily affixing a second hanger assembly on the second guide rod, affixing a first semi-cylindrical half shield to the first hanger assembly, affixing a second semi-cylindrical half shield to the second hanger assembly, clamping together abutting edges of the first and second semi-cylindrical half shields to form a cylindrical radiation shield, clamping the cylindrical radiation shield to the control rod drive, and releasing the first and second semi-cylindrical half shields from the first and second hanger assemblies, whereby the cylindrical radiation shield may remain on the control rod drive during movement thereof.
The above, and other objects, features and advantages of the present invention will become apparent from the following description read in conjunction with the accompanying drawings, in which like reference numerals designate the same elements.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified cross section of a portion of a containment and a reactor vessel.
FIGS. 2-5 are steps in the conventional manner used for removing a control rod drive from a nuclear reactor.
FIG. 6 is a top view of a control rod drive handling system according to an embodiment of the invention.
FIG. 7 is a side view of the control rod drive handling system of FIG. 6.
FIG. 8 is a front view of the control rod drive handling system of FIG. 6.
FIG. 9 is a front view of the control rod drive handling system showing an early stage in the removal of a control rod drive.
FIG. 10 is a front view of the control rod drive handling system showing a later stage in the removal of a control rod drive.
FIG. 11 is a top view of a detent collar.
FIG. 11A is a top view of a detorque yoke.
FIG. 12 is a close-up front view of a portion of the control rod handling system showing a torque breaker installed for loosening holding bolts.
FIG. 13 is a close-up side view of the bottom of the control rod drive showing the installation of guide rods and safety blocks.
FIG. 14 is a top view of a safety block
FIG. 15 is a front view of the control rod drive handling system showing a later stage in the removal of a control rod drive.
FIG. 16 is a front view of the control rod drive handling system showing the next stage of lowering a control rod drive for removal.
FIG. 17 is a front view of the control rod drive handling system showing the final stage of lowering a control rod drive for removal.
FIG. 18 is a side view of the control rod handling system wherein the tower is rotated into the horizontal position.
FIG. 19 is a partially disassembled view of an effluent container according to an embodiment of the invention.
FIG. 20 is a cross section taken along XX--XX in FIG. 19.
FIG. 21 is a cross section taken along XXI--XXI in FIG. 19.
FIG. 22 is a perspective view of a radiation shield pig according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1, there is shown, generally at 10, a nuclear reactor having a containment 12 with a reactor vessel 14 therein. It will be recognized by one skilled in the art that different nuclear reactors 10may have numbers and dimensions which may vary from the illustrative example used in the preceding. The apparatus and methods of the present invention are equally adaptable to such other systems.
A control rod drive 16, which may be one of, for example, 180 such items, is affixed in reactor vessel 14 using a flange 18 affixed to a bottom 20 of reactor vessel 14 that mates with a flange 22 affixed to control rod drive 16. Flanges 18 and 22 are urged together by a ring of bolts 24. A criss-cross pattern of heavy steel plates 26 form eggcrate compartments below bottom 20 to surround external parts of control rod drive 16, to catch control rod drives 16 in case of an accident, and for protection of instrumentation (not shown) affixed below bottom 20. An inverted jungle ofrelatively fragile instrumentation cables 28 is suspended below bottom 20 (only one instrumentation cable 28 is represented in the figure to reduce clutter).
A sub-pile room 30 in containment 12 below reactor vessel 14 is divided by a rotatable work platform 32 into an upper portion 34 and a lower portion 36. A floor 38 is located at the bottom of lower portion 36. A door 40 in containment 12 permits entry and exit of personnel and equipment.
In a typical nuclear reactor 10, sub-pile room 30 measures about 18 feet from floor 38 to bottom 20. A typical control rod drive 16 is about 16 feet long. There is thus a minimum of maneuvering room for lowering control rod drive 16 and upending it for passage through door 40. Work platform 32 is positioned so that its work surface 42 is about five to seven feet below a bottom 44 of steel plates 26. This permits workers on work surface 42 to reach items mounted on bottom 20, but it also provides a relatively cramped workspace.
Referring now to FIG. 2, there is shown an early step in the removal of a control rod drive 16. Elements not necessary to the following description are omitted.
Bolts 24 are removed and a cable 46 of a hoist 48 is attached to control rod drive 16. Referring now to FIG. 3, control rod drive 16 is lowered until the balance point of control rod drive 16 has emerged from flange 18. It will be noted that, at this time, the bottom of control rod drive 16 is below work platform 32. A slot in work platform 32 provides for this.
Referring now to FIG. 4, cable 46 is re-rigged at the balance point of control rod drive 16.
Referring now to FIG. 5, lowering continues until the top of control rod drive 16 clears flange 18, as shown in solid line. Then control rod drive 16 is rotated about its balance point to the horizontal condition, as shown in dashed line. Once in the horizontal position, it may be removed from sub-pile room 30 using, for example, a trolley cart (not shown).
It should be evident that the rigging, rerigging, lowering and rotating steps in the prior art technique provide less than optimum control of control rod drive 16 during the process. The poor control of control rod drive 16 presents a substantial danger of damage to instrumentation cables(not shown in FIGS. 2-5). Also, the manual method consumes substantial time. It is estimated that a crew of four workers is capable of removing or installing about two control rod drives 16 in an eight-hour shift. Thislow level of productivity is worsened if an instrumentation cable is damaged and has to be repaired before proceeding.
Referring now to FIG. 6, there is shown, generally at 50, a handling systemaccording to the present invention. A slot 52 in work surface 42 includes opposed support rails 54 and 56. A trunnion cart 58 includes a plurality of wheels 60 rolling on rails 54 and 56. Trunnion cart 58 supports a tower62. A winch 64 is affixed to work platform 32 at one end of slot 52. A cable 65 is paid out from winch 64 for attachment to the bottom of tower 62, as will be explained. A lead cart 66, whose structure and function will be described later, is rollably supported on rails 54 and 56 by a plurality of wheels 68.
Referring now to FIG. 7, tower 62 includes first and second facing side rails 70 and 72 (side rail 72 is hidden by side rail 70 in FIG. 7). Side rails 70 and 72 are tied together by a plurality of cross braces 74. Cable65 is affixed near the bottom of side rail 70 by any convenient means such as, for example, a safety hook 76 on cable 65 engaging an eye 78 on side rail 70. An hoist motor 80 is affixed at the bottom end of side rail 70. An extension piece 82, used at various stages of removal and installation of a control rod drive, is shown alongside tower 62. A torque breaker 84 and a load transfer plate 86 are also shown.
Referring now to the front view of tower 62 in FIG. 8, an elevator platform88 is driveable upward and downward between side rails 70 and 72 by actuation of hoist motor 80. Any convenient means for transferring motion from hoist motor 80 to elevator platform 88 may be employed. In one embodiment of the invention, a cross shaft 90 is driven through a roller chain 92 from hoist motor 80. An endless roller chain (not shown) inside side rail 70, and a further endless roller chain (not shown) inside side rail 72, are driven by cross shaft 90. The ends of elevator platform 88 are connected to the two roller chains whereby, as cross shaft 90 rotates,elevator platform 88 is moved upward or downward. Other techniques for driving elevator platform 88 would be evident to one skilled in the art, and thus do not require further elaboration.
A retractable wheel 94 is affixed near the lower end of side rail 70. Similarly, a retractable wheel 96 is affixed near the lower end of side rail 72. In the retracted position shown, the maximum transverse dimensionthrough retractable wheels 94 and 96 is less than the spacing between rails56, whereby retractable wheels 94 and 96 can pass therethrough. Later in the operation of the system, tower 62 is rotated until retractable wheels 94 and 96 are above rails 56. Then retractable wheels 94 and 96 are moved into their unretracted positions. The end of tower 62 may then be lowered until retractable wheels 94 and 96 contact the upper surfaces of rails 56 to support tower 62.
It is to be noted that the transverse dimension of hoist motor 80 is less than the space between rails 56. This permits rotation of tower 62 to movehoist motor 80 upward between rails 56 during a stage of operation of the system.
A journal shaft 100, extending from side rail 70, is rotatably engaged in atrunnion bearing 98 on one trunnion cart 58. Similarly, a journal shaft 102, extending from side rail 72, is rotatably engaged in a trunnion bearing 104 on the other trunnion cart 58.
Referring now to FIG. 9, the apparatus of the invention is shown in an early stage of use. Extension piece 82 includes a shaft 106 having a support 108 at its lower end for engaging elevator platform 88. A cylindrical bearing 110 supports an upward-pointing locating pin 112. Locating pin 112 is sized to enter an axial hole 114 in the bottom of control rod drive 16. An indexing guide 116 is disposed about an intermediate point on shaft 106. A detorque yoke 118 is installed above indexing guide 116.
Referring now to FIG. 10, in the next stage in removal of control rod drive16, elevator platform 88 is raised until locating pin 112 enters axial hole114 (neither of which are seen in FIG. 10). Cylindrical bearing 110 permitsa limited rotation of locating pin 112 to facilitate its entry into, and alignment with axial hole 114. Initially, elevator platform 88 is positioned so that no upward force is applied to the bottom of control roddrive 16. This permits extension piece 82 to be rotated, as desired.
Referring momentarily to FIG. 11, indexing guide 116 is formed of first andsecond semi-circular halves 117 and 119, permanently installed on shaft 106using, for example, bolts 121. A plurality of radial slots 120, equal in number to bolts 24 securing control rod drive 16 are formed in an upper surface. Radial slots 120 give indexing guide 116 an appearance similar toa castellated nut.
Referring now to FIG. 11A, detorque yoke 118 includes a wishbone-shaped member 122 having first and second legs 124 and 126 enclosing a gap 128. Aclosing bar 129 is secured in place closing gap 128 using, for example, a nut 131. A boss 133, on the underside of detorque yoke 118, engages a selected one of radial slots 120, as will be explained hereinafter. A hole137 is sized to permit the entry thereinto of a lower end of torque breaker
Returning now to FIG. 10, torque breaker 84 includes a shaft 130 having a socket-engaging portion 132 at one end thereof, and a guide rod 134 at theother. A coil spring 136 covers at least part of guide rod 134. A handle 138 is fitted in torque breaker 84 above coil spring 136. Guide rod 134 issized to fit into hole 137. The length of shaft 130 is such that, guide rod134 may be pressed downward into a hole 137, thereby compressing coil spring 136 to permit socket-engaging portion 132 to be moved into alignment with a bolt 24. When downward force on torque breaker 84 is removed, coil spring 136 urges socket-engaging portion 132 upward into full engagement with a bolt 24, while guide rod 134 remains within hole 137.
The engaged position of torque breaker 84 is shown in FIG. 12.
In an initial adjustment, while extension piece 82 is held in the unforced position shown in FIG. 10, extension piece 82 is rotated until radial slots 120 in indexing guide 118 are aligned below respective ones of bolts24. Selection of this alignement may be aided by installing detorque tool 84 in hole 137 and in one of bolts 24. When substantial rotational alignment is attained, elevator platform 88 is urged upward by hoist motor80 until a substantial upward force is exerted on the bottom of control roddrive 16 by extension piece 82. This force is sufficient to hold extension piece 82 in the selected rotational position and to provide reaction torque to permit adequate torque to be applied to bolt 24 by manual actuation of handle 138. In one embodiment of the invention, the full upward drive capability of hoist motor 80 is applied and maintained duringthe detorquing of bolts 24. The applied upward force of about 1000 pounds was adequate to permit detorquing of bolts 24 which are installed with a torque of 800 foot-pounds.
Once one of bolts 24 is loosened, boss 133 is disengaged from a radial slot120, and detorque yoke 118 is rotated until hole 137 is aligned below a next selected bolt 24. Since radial slots 120 are generally aligned with bolts 24, the new position of detorque yoke 118 is certain to align hole 137 vertically with the selected bolt 24.
Numerous conventional mechanisms could be substituted for the apparatus described above for providing the indexing function. A detailed discussionof such conventional mechanisms is considered unnecessary to satisfy the disclosure requirements of the present application.
It is found most productive to use torque breaker 84 only to break the initial torque. Once all of bolts 24 are loosened slightly, torque breaker84 is removed, and all bolts 24 can be removed rapidly with a low-powered electric or pneumatic drive.
Referring now to FIGS. 12 and 13, as a preferable next step in the removal of control rod drive 16 one pair of diametrically opposite bolts 24 are removed and a pair of guide rods 140 are screwed, hand tight, in their place. Each guide rod 140 includes a tapered tip 142 at its end, and a narrow diameter portion 144 in an intermediate location. A safety block 146 is installed on the narrow diameter portion 144 of each guide rod 140.
Each safety block 146 includes a slot 148 having a width permitting it to fit onto narrow diameter portion 144, and to prevent it from being forced axially along guide rod 140. Thus, in the event that control rod drive 16 is released accidentally, safety blocks 146 stop downward motion of control rod drive 16 after only a small amount of motion has taken place.
When a maintenance operation requires removal of a control rod drive 16 andits reinstallation or replacement, guide rods 140 are permitted to remain in place after removal, or are installed in preparation for reinstallation. The presence of guide rods 140 simplifies attaining correct linear and rotational alignment of flange 22 with flange 18.
Referring now to FIG. 15, elevator platform 88 is lowered until the bottom of control rod drive 16 enters the top of tower 62. Conventional guiding elements at the top of tower 62, which may be employed to stabilize extension piece 82 during the process of reaching the condition shown, areomitted to reduce clutter in the figure. At this point, extension piece 82 must be removed so that control rod drive 16 can be further lowered into tower 62.
Referring now to FIG. 16, a load transfer plate 150 is slid into place in tower 62 to bear the load of control rod drive 16 while elevator platform 88 is lowered further to disengage extension piece 82 from the bottom of control rod drive 16. Extension piece 82 is then removed, supported by an integral hanger, and swung aside in preparation for the next step in removal. With extension piece 82 removed, elevator platform 88 is moved upward to assume support of control rod drive 16. Load transfer plate 150 is removed.
Referring now to FIG. 17, elevator platform 88 is lowered until a top end 152 of control rod drive 16 is clear of flange 18.
Referring now to FIG. 18, winch 64 is actuated to raise the lower end of tower 62 until retractable wheels 94 and 96 are above rails 56. In this raising operation and by referring to FIGS. 7, 8, 17 and 18, it is seen that the entire tower structure is pivoted or rotated to effect this raising. As FIG. 8 shows, an upper end of the tower has support on trunnion cart 58 via the two journal shafts 100, 102 and their companion trunnion bearings 98, 104. The journal shafts 100, 102 serve as pivot points so that when cable 65 is taken up, the lower tower end is lifted and the whole tower structure pivots about these said pivot points to bring the tower lower end slightly above horizontal. The short length of tower 62 seen extending above rail 54 in FIG. 8 will of course also pivot,but downwardly slightly as part of the shifting of tower orientation from vertical to generally horizontal. Then, retractable wheels 94 and 96 are moved into their outward unretracted positions, and cable 65 is paid out slightly until retractable wheels 94 and 96 rest on rails 56 to support the end of tower 62. Safety hook 76 is disengaged from eye 78 so that tower 62 is converted to a rollable cart which can be rolled out through door 40 (FIG. 1). Tower 62 can similarly be used to move control rod drive16 inward through door 40 in preparation for installation.
In some installations, the bottom of door 40 is raised a substantial distance above work surface 42. Generally a ramp (not shown) is provided so that materials can be rolled up and down between the two levels. Such aramp could contact top end 152 of control rod drive 16 during the transition from work surface 42 to the ramp, possibly causing damage.
Referring again to FIG. 6, lead cart 66 solves the problem of maneuvering control rod drive 16 in tower 62 onto a ramp without damaging top end 152 of control rod drive 16. When tower 62 is brought to the horizontal position, the protruding end of control rod drive 16 is clamped into clamps 154 and 156 in lead cart 66. Thus, as tower 62 and control rod drive 16 are moved onto a ramp, lead cart 66 rolls up the ramp to raise top end 152. It may be desirable to block rotation of control rod drive 16with respect to tower 62. In this event, when lead cart 66 rolls up a ramp,trunnion cart 58 may be raised off rails 56, thereby leaving control rod drive 16 and tower 62 supported by lead cart 66 and retractable wheels 94 and 96.
Two additional problems are solved by the present invention. When the seal between flanges 18 and 22 is first cracked during removal, an initial burst of contaminated water pours out through the gap between them. In themost common situation, this water pours down over the workers below. Although the workers wear protective clothing and breathing gear, it is considered undesirable to permit such contaminated water to fall on them. One Japanese Utility Model Application Publication NO. 57-49834, employs asump that can be affixed to the control rod drive to catch and channel awaywater as the seal between flanges 18 and 22 is cracked.
Top end 152 of control rod drive 16 is located closest to the nuclear reaction in reactor vessel 14, and a filter therein tends to collect radioactive contaminants. Thus this area is much more radioactive than is the remainder of control rod drive 16. In the prior art, a cylindrical lead radiation shield pig is placed over top end 152 to shield against theradiation in this area. A lead cylinder of the required size and thickness is relatively heavy and difficult to handle quickly. Thus, more radiation exposure occurs than is desirable. The present invention addresses this problem with a radiation shield pig that permits faster and more positive installation of shielding upon top end 152.
Referring to FIGS. 19-21, an effluent container 158 is shown with its elements partially installed to catch and channel effluent water that willescape between flanges 18 and 22 when the seal between them is broken.
Four sway braces 160 are conventionally disposed, 90 degrees apart, in contact with each flange 18. A water container 161 consists of two halves 162 and 164 having half-cylindrical sidewall 166 and 168 with half-circular bottoms 170 and 172, respectively. Bottoms 170 and 172 include semi-circular cutouts 174 and 176, respectively which, when halves162 and 164 are fitted together, form a close fit to the outer peripheral surface of extension piece 82. Four notches 178, 180, 182 and 184 are positioned and sized to slip over the four sway braces 160. A hole 186 in bottom 170 is connected to a drainage nipple 188 outside water container 161. A flexible hose 190 carries off water that falls into water container161.
A clamp cylinder 192 consists of a right circular cylinder having a single vertical split 194 therein. The material of clamp cylinder 192 is resilient enough to permit deformation to expand split 194 sufficiently topass over extension piece 82. Four L-shaped slots 196, 198, 200 and 202 (L-shaped slot 202 is hidden in the figure), are disposed in the upper edge of clamp cylinder 192. The L-shaped slots fit upon sway braces 160 and, when clamp cylinder 192 is rotated slighty, hook over the top thereofto retain clamp cylinder 192 in the installed position. In this position, clamp cylinder 192 holds the two halves of water container 161 together.
In use, bolts 24 are removed while a strong upward force is exerted on control rod drive 16 through extension piece 82. This prevents any substantial leakage during the initial stages. Halves 162 and 164 are assembled upon extension piece 82 with notches 178, 180, 182 and 184 engaging their respective sway braces 160. Split 194 is opened to permit slipping clamp cylinder 192 over extension piece 82. Clamp cylinder 192 isslid upward over the outside of water container 161 and L-shaped slots 196,198, 200 and 202 are latched over their respective sway braces 160.
Extension piece 82 is then lowered slightly to break the seal between flanges 18 and 22. This permits liquid effluent to drain into water container 161 and thence through 190 to a location where it can be controlled. Control rod drive 16 may be lowered still further as desired. At some point, water container 161 begins sliding downward within clamp cylinder 192, which stays in place.
The fit between mating edges of halves 162 and 164 is close enough to limitleakage therepast to a very small amount. Similarly, the fit of semi-circular cutouts 174 and 176 is close enough to limit leakage. Although gasketing could be used on these mating surfaces to reduce even further the leakage, such an addition may not be needed since the principal goal of eliminating the shower of contaminated water has been substantially attained.
Water container 161 and clamp cylinder 192 may be made of any convenient material. We have discovered that a plastic resin, and especially a polycarbonate plastic resin, has suitable properties of lightness, strength and resilience for these parts. Typical polycarbonate resins are transparent. This provides the important benefit of permitting a worker tosee the flow of water inside, and thus to monitor proper drainage, and to determine when substantially all of the water flow is completed.
Referring now to FIG. 22, there is shown, generally at 204, a radiation shield pig according to an embodiment of the invention. A hanger assembly 206 includes a top bar 208 and a bottom bar 210 rigidly tied together in parallel spaced-apart relationship by a connecting pin 212. Top bar 208 includes a hole 214 therein fittable over guide rod 140. Similarly, bottombar 210 includes a hole 216, axially aligned with hole 214 and also fittable over guide rod 140. A spring-loaded latch 218 snaps into a latching position in narrow diameter portion 144 when hanger assembly 206 is slipped upward onto guide rod 140. First and second swing arms 220 and 222 are pivoted to connecting pin 212.
A half shiedl 224, of semi-cylindrical shape, includes a connecting loop 226 on an outer surface thereof. Each of swing arms 220 and 222 includes ahole 228 (hole 228 in swing arm 222 is not visible in the figure) to receive a connecting pin 230, which also passes through connecting loop 226 to pivotably affix half shield 224 to guide rod 140.
A clamp hanger 232, affixed to half shield 224 at its upper end, is pivotably attached at its lower end to a friction clamp half 234. First and second hooks 236 and 238 are disposed adjacent an edge of half shield 224. A second half shield 240 inlcudes elements thereon that correspond tothose on half shield 224. First and second luggage latches 242 and 244 are positioned where they can be engaged with hooks 236 and 238, respectively on half shield 224. A further pair of luggage latch components is hidden adjacent the rear mating surfaces of radiation shield pig 204. In a further embodiment, only one latch is used at each side of radiation shield pig 204.
In use, while top end 152 of control rod drive 16 is still well above flange 18, the two half shields 224 and 240 of shield pig 204 are installed on guide rods 140 in the unengaged position shown. Then, when the highly radioactive top end 152 emerges from flange 18, luggage latches242 and 244 are latched to form a complete cylinder about top end 152, and the two friction clamp halves 234 are clamped together about control rod drive 16, whereby shield pig 204 is firmly secured to control rod drive 16. Then the two connecting pins 230 (one hidden in the figure) are pulled. This releases radiation shield pig 204 for movement with control rod drive 16.
This required actions following emergence of top end 152 are accomplished rapidly and positively, whereby a minimum of radiation exposure occurs.
Having described preferred embodiments of the invention with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims. | A low-headroom tower is pivotably mounted to a trunnion cart that runs on rails in a slot in a work platform located in the sub-pile room of a reactor containment. An elevator in the tower raises an extension piece into contact with the bottom of a control rod drive. A detorquing guide is rotationally positioned to coincide with bolts holding the control rod drive in place. The elevator places an upward force on the control rod drive during detorquing of the bolts. This provides reaction torque to aid in bolt loosening and prevents leakage of contaminated effluent past the seal. A detorquing tool is fitted into the detorquing guide and is spring loaded to engage a selected bolt securing the control rod drive. An indexing device provides alignment for the detorquing tool with each succeeding bolt. The elevator is lowered until the bottom end of the control rod drive enters the tower. The load is transferred from the extension piece directly to the elevator. Lowering continues until the top end of the control rod drive emerges from the reactor vessel. Normally retracted rear wheels are attached to the tower. A winch rotates the tower to the horizontal position, and the rear wheels are extended to engage with the rails to permit rolling horizontal movement of the tower. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates a wireless communications terminal apparatus which is able to determine its present position, using radio frequency signals, and, more particularly, to such apparatus capable of accurate calculation of its position even when it is in the vicinity of a repeater.
[0003] 2. Description of Related Art
[0004] Techniques for determining the position of a wireless communications terminal apparatus (mobile station), using signals transmitted from base stations in a mobile communications system have so far been proposed. For example, such a technique was proposed in JP-A No. 181242/1995 that the position of a mobile terminal is determined by using the positions of base stations and difference of propagation delay time of signals transmitted from the base stations to the terminal in a code division multiple access (CDMA) system.
[0005] Referring to FIG. 2, the above technique is explained. A mobile station MS receives signals from three base stations existing in its periphery performs correlation processing of the received signals, and determines timing of each signal reception. From the determined timing of each signal reception, delay time difference of signal reception timing from the base stations (in proportion to difference in distance of the mobile station from the base stations) is calculated. Using the thus calculated delay time difference, by evaluating the equations given in FIG. 2, the position of the mobile station can be obtained.
[0006] In a conventional mobile communications system in which the above-explained technique is applied, a repeater (RP) that receives signals from a particular base station BS 1 and retransmits the signals is installed in addition to the base stations as is shown in FIG. 3. Such repeater is capable of extending the area within which cellular communications can be implemented with less cost. Thus, repeaters are widely used, especially for extending indoor service areas. However, the repeater RP receives signals transmitted by the particular base station BS 1 and transmits the signals as is. Therefore, the repeater RP transmits the same signals as those that the base station BS 1 transmits. The time of receiving a signal transmitted by the repeater is later than the time of receiving the signal directly transmitted from the base station BS 1 due to signal processing on the repeater. A chart presented at the top of the page of FIG. 3 shows a delay profile of measured time of signal reception from the repeater in a wireless communications system in practical use. PN 0 is a signal from the base station nearest to the mobile station and a correlation value representing intensive power of the signal is obtained. PN 1 is a signal from the base station BS 1 ; the signal being repeated by the repeater RP connected to the BS 1 . Timing when the mobile station MS would receive the signal directly from BS 1 on the supposition that the signal is not repeated is marked with a dotted line in the chart.
[0007] When the mobile station comes near the repeater, it receives a signal of large delay repeated by the repeater. From the chart of the PN 1 signal, it is seen that the mobile station receives the signal repeated by the repeater with delay equivalent to 12 km longer than the distance between the BS 1 and the mobile station MS which would otherwise be calculated from the assumed time of reception of the signal directly transmitted from the BS 1 . Position calculation of the mobile station using the repeated signal results in a mobile station position with quite a large error.
[0008] Briefly, problems of the conventional method in which a wireless communications terminal (mobile station) determines its position are that we have had:
[0009] (1) No method of detecting a repeater; and
[0010] (2) No method of mitigating the influence of the repeater on the terminal position determination even if the repeater was detected by some means or other.
SUMMARY OF THE INVENTION
[0011] The object of the present invention is to provide a wireless communications terminal apparatus that calculates its accurate position, mitigating the influence of a repeater on the calculation without using complicated processing.
[0012] In order to solve the above-noted problems, the present invention in one aspect provides a wireless communications terminal apparatus which receives signals transmitted from a plurality of radio stations and calculates its position, using the received signals. This terminal apparatus comprises repeater detection means for detecting a signal from a repeater which transmits signals that are generated on the basis of signals transmitted from one of the radio stations and indistinguishable from the signals transmitted from that radio station from among the received signals and position calculation means for calculating its position. When the repeater detection means has detected a signal from a repeater, the position calculation means ignores the detected signal from the repeater and calculates the terminal position, using the received signals from other radio stations.
[0013] In another aspect, the invention provides a wireless communications terminal apparatus which receives signals transmitted from a plurality of radio stations and calculates its position by using the received signals, comprising repeater detection means for detecting a signal from a repeater which transmits signals that are generated on the basis of signals transmitted from one of the radio stations and indistinguishable from the signals transmitted from that radio station from among the received signals and position calculation means for calculating its position, wherein, when the repeater detection means has detected a signal from a repeater, the position calculation means determines the location of the repeater transmitting the detected signal as the position of the terminal apparatus.
[0014] In yet another aspect, the invention provides a system for determining terminal position, comprising the following: radio stations which transmit signals to a wireless communications terminal apparatus; a repeater which transmits signals that are generated on the basis of signals transmitted from one of the radio stations and indistinguishable from the signals transmitted from that radio station; a wireless communications terminal apparatus which receives signals from a plurality of radio stations for calculating its position, using the received signals; repeater detection means for detecting a signal from the repeater from among the received signals; and position calculation means for calculating the position of the terminal apparatus, wherein, when the repeater detection means has detected a signal from a repeater, the position calculation means ignores the detected signal from the repeater and calculates the position of the terminal apparatus, using the received signals from other radio stations.
[0015] In yet another aspect, the invention provides a system for determining terminal position, comprising the following: radio stations which transmit signals to a wireless communications terminal apparatus; a repeater which transmits signals that are generated on the basis of signals transmitted from one of the radio stations and indistinguishable from the signals transmitted from that radio station; a wireless communications terminal apparatus which receives signals from a plurality of radio stations for calculating its position, using the received signals; repeater detection means for detecting a signal from the repeater from among the received signals; and position calculation means for calculating the position of the terminal apparatus, wherein, when the repeater detection means has detected a signal from a repeater, the position calculation means determines the location of the repeater transmitting the detected signal as the position of the terminal apparatus.
[0016] In a further aspect, the invention provides a position calculation method by which a wireless communications terminal apparatus receives signals transmitted from a plurality of radio stations and calculates its position, using the received signals. The position calculation method comprises a repeater detection step for detecting a signal from a repeater which transmits signals that are generated on the basis of signals transmitted from one of the radio stations and indistinguishable from the signals transmitted from that radio station from among the received signals and a position calculation step for calculating the position of the terminal apparatus, wherein, when a signal from a repeater has been detected by the repeater detection step, the detected signal from the repeater is ignored and the position of the terminal apparatus is calculated by using the received signals from other radio stations in the position calculation step.
[0017] In a still further aspect, the invention provides a position calculation method by which a wireless communications terminal apparatus receives signals transmitted from a plurality of radio stations and calculates its position, using the received signals, the position calculation method comprising a repeater detection step for detecting a signal from a repeater which transmits signals that are generated on the basis of signals transmitted from one of the radio stations and indistinguishable from the signals transmitted from that radio station from among the received signals and a position calculation step for calculating the position of the terminal apparatus, wherein, when a signal from a repeater has been detected by the repeater detection step, the location of the repeater transmitting the detected signal is determined as the position of the terminal apparatus in the position calculation step.
[0018] In a further aspect, the invention provides a server apparatus which is used in the above system for determining terminal position to calculate the position of a wireless communications terminal apparatus which received signals from a plurality of radio stations. The server apparatus comprises position calculation means for calculating the position of the terminal apparatus, based on timing when the wireless communications terminal apparatus received the signals, and repeater detection means for detecting a signal from a repeater which transmits signals that are generated on the basis of signals transmitted from one of the radio stations and indistinguishable from the signals transmitted from that radio station from among the received signals, wherein, when the repeater detection means has detected a signal from a repeater, the position calculation means ignores the detected signal from the repeater and calculates the position of the terminal apparatus, using the received signals from other radio stations.
[0019] In a still further aspect, the invention provides a server apparatus which calculates the position of a wireless communications terminal apparatus which received signals from a plurality of radio stations, the server apparatus comprising position calculation means for calculating the position of the terminal apparatus, based on timing when the wireless communications terminal apparatus received the signals, and repeater detection means for detecting a signal from a repeater which transmits signals that are generated on the basis of signals transmitted from one of the radio stations and indistinguishable from the signals transmitted from that radio station from among the received signals, wherein, when the repeater detection means has detected a signal from a repeater, the position calculation means determines the location of the repeater transmitting the detected signal as the position of the terminal apparatus.
[0020] In a further aspect, the invention provides an apparatus fabricated with semiconductor integrated circuits, which is used as the above wireless communications terminal apparatus, having a memory into which a program can be stored and a CPU, wherein a computer-executable program is stored into the memory and the CPU executes the program stored and retained in the memory. The program comprises a repeater detection step for detecting a signal from a repeater which transmits signals that are based on signals transmitted from one of the radio stations and indistinguishable from the signals transmitted from that radio station from among the received signals and a position calculation step for calculating the position of the terminal apparatus, wherein, when a signal from a repeater has been detected by the repeater detection step, the detected signal from the repeater is ignored and the position of the terminal apparatus is calculated by using the received signals from other radio stations in the position calculation step.
[0021] In a still further aspect, the invention provides an apparatus fabricated with semiconductor integrated circuits having a memory into which a program can be stored and a CPU, wherein a computer-executable program is stored into the memory and the CPU executes the program stored and retained in the memory. The program comprises a repeater detection step for detecting a signal from a repeater which transmits signals that are generated on the basis of signals transmitted from one of the radio stations and indistinguishable from the signals transmitted from that radio station from among the received signals and a position calculation step for calculating the position of the terminal apparatus, wherein, when a signal from a repeater has been detected by the repeater detection step, the location of the repeater transmitting the detected signal is determined as the position of the terminal apparatus in the position calculation step.
[0022] In order to solve the above-noted problems and in accordance with one implementation of the invention, a wireless communications terminal apparatus which receives signals transmitted from a plurality of radio stations and calculates its position by using the received signals comprises repeater detection means for detecting a signal from a repeater which transmits signals that are generated on the basis of signals transmitted from one of the radio stations and indistinguishable from the signals transmitted from that radio station from among the received signals and position calculation means for calculating its position, wherein, when the repeater detection means has detected a signal from a repeater, the position calculation means determines the location of the repeater transmitting the detected signal as the position of the terminal apparatus. Thus, accurate terminal position determination can be carried out even in a wireless cellular communications system in which repeaters exist, and only slight change is required for implementing that.
[0023] According to another implementation of the invention, a wireless communications terminal apparatus which receives signals transmitted from a plurality of radio stations and calculates its position by using the received signals comprises repeater detection means for detecting a signal from a repeater which transmits signals that are generated on the basis of signals transmitted from one of the radio stations and indistinguishable from the signals transmitted from that radio station from among the received signals and position calculation means for calculating its position, wherein, when the repeater detection means has detected a signal from a repeater, the position calculation means determines the location of the repeater transmitting the detected signal as the position of the terminal apparatus. Because repeaters are intended to cover a small area such as indoor space, they are characterized in that their transmitting power is generally lower than the transmitting power of other base stations. When the terminal receives the most powerful signals from a possible repeater in comparison with the signals from other base stations, it is reasonable to consider that the terminal is very near to the repeater. Thus, accurate terminal position determination can be carried out even in a wireless cellular communications system in which repeaters exist.
[0024] The above-mentioned repeater detection means compares timing of receiving a signal from one radio station and timing of receiving a signal from another radio station and determines that one radio station is a repeater, based on the result of the comparison (for example, when the timing of receiving the signal from one radio station is later than the timing of receiving the signal from another radio station by a predetermine time and longer) . Thus, repeater detection can be carried out without using a complicated method.
[0025] When the terminal apparatus can observe signals only in a predetermined number of sectors from one of the radio stations, the above-mentioned repeater detection means determines that the one of the radio stations is a repeater. Normally, a cellular base station transmits signals in multiple sectors. When the terminal is very near to a base station, it observers signals in a plurality of sectors transmitted from the base station. However, a repeater repeats only one of the plurality of sectors transmitted from a base station. When the terminal is very near to a repeater, in most cases, it observes signals in one of the plurality of sectors. Thus, repeater detection can be carried out without using a complicated method.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The invention will be more particularly described with reference to the accompanying drawings, in which:
[0027] [0027]FIG. 1 is a block diagram showing the configuration of a wireless communications terminal apparatus according to a preferred embodiment of the present invention;
[0028] [0028]FIG. 2 is a schematic drawing that explains the principle of locating the wireless communications terminal apparatus according to a preferred embodiment of the present invention;
[0029] [0029]FIG. 3 shows delay profiles of measured signals received from a plurality of stations when the terminal (mobile station) is near a repeater;
[0030] [0030]FIG. 4 is a flowchart illustrating a position calculation method of Embodiment 1;
[0031] [0031]FIG. 5 is a flowchart illustrating a repeater detection method of Embodiment 1;
[0032] [0032]FIG. 6 is a flowchart illustrating another position calculation method of Embodiment 2;
[0033] [0033]FIG. 7 is a flowchart illustrating another repeater detection method of Embodiment 2;
[0034] [0034]FIG. 8 is a graph of delay profiles of measured pilot signals from base stations and a repeater in the vicinity of the terminal when the terminal is very near to the repeater;
[0035] [0035]FIG. 9 is a flowchart illustrating a sync channel detection method of Embodiment 2; and
[0036] [0036]FIG. 10 is a block diagram showing the configuration of a system for determining wireless terminal position according to a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] The present invention now is described fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown.
[0038] [0038]FIG. 1 is a block diagram showing the configuration of a wireless communications terminal apparatus according to a preferred embodiment of the present invention.
[0039] The wireless communications terminal apparatus according to this embodiment of the invention is essentially comprised of an antenna 1 , RF unit 2 , baseband unit 3 , storage 7 , and CPU 8 . The baseband unit 3 comprises a despreader 4 , detection block 5 , and correlator 6 . Signals from base stations are received by the antenna 1 and transferred to the RF unit 2 . The RF unit 2 consists of a receiving portion and a transmitting portion. The RF unit 2 performs receive processing such as amplification at high and intermediate frequencies and frequency conversion for the signals from the base stations, received by the antenna 1 , and converts them to baseband signals.
[0040] The procedure in which the wireless communications terminal apparatus of this embodiment carries out its position calculation will be explained below. Assume that the terminal is communicating with base stations in a TIA/EIA/IS-95 system which is a cellular system using CDMA. In the TIA/EIA/IS-95 system, the base stations transmit pilot signals of a fixed pattern. Each base station transmits a pilot signal at timing based on PN offset predetermined for each base station, behind the system clock. The terminal first determines what base station is the nearest to it. To do this, the correlator 6 for pilot channels operates for seeking timing when the highest correlation peak occurs as the phase of pilot signals supplied to the correlator changes sequentially. The thus detected peak position is timing in synchronization with signal reception from the base station regarded as the nearest to the terminal.
[0041] The baseband unit 3 includes the despreader 4 for control channels. The despreader 4 performs despread processing at the detected timing of signal reception from the base station nearest to the terminal and control channel signals are picked out. The picked out control channel signals are detected by the detection block 5 and demodulated into significant information. The CPU 8 extracts the ID of the base station from which the terminal is receiving the signals from the thus picked up signals. The CPU 8 looks through an information table for base stations in the periphery of the terminal, which has been stored into the memory 7 beforehand, and gets the PN offsets of the base stations in the vicinity of the terminal. With regard to timing based on the PN offsets of the base station nearest to the terminal and other base stations in the vicinity of the terminal, a delay profile is created, using the correlator 6 for pilot signals. The thus created delay profile is stored into the storage 7 . The CPU 8 analyzes the delay profile stored in the storage 7 and picks up timing when a direct wave propagation path from each base station in the vicinity of the terminal has been detected. The picked up timings for each base station correspond to propagation time T1, T2, and T3 of direct waves from each base station in the terminal (mobile station), which are shown in FIG. 2. Furthermore, the CPU 8 evaluates the equations given in FIG. 2, using the method of least squares, thus calculating the position of the terminal (mobile station). For this position calculation, the IDs, PN offsets, and positions of the base stations are necessary, which must be stored into the memory of the terminal beforehand.
[0042] [0042]FIG. 2 is a schematic drawing that explains the principle of locating the wireless communications terminal apparatus according to the preferred embodiment of the invention.
[0043] The terminal (mobile station) MS receives signals from three base stations BS 1 , BS 2 , and BS 3 in the vicinity of the MS. Each base station has time in synchronization with a GPS or network and all base stations that belong to the radio communications system have a synchronized precise clock. Each base station transmits signals of a fixed pattern controlled in synchronization with the clock. The terminal (mobile station) MS knows beforehand the signal pattern to be transmitted from each station and the correlator performs correlation processing between the pattern and the received signals and detects timing of signal reception from each base station. From the detected timing, the timings of signal reception from the base stations BS 1 , BS 2 , and BS 3 are determined as T1, T2, and T3. Time difference by signal reception delay from each base station, that is, T1 minus T2 and T3 minus T2 are calculated. Because this delay time difference is proportional to difference in distance of the terminal from the base stations, by evaluating the equations given in FIG. 2 by using the method of least squares, the terminal position (x, y) can be obtained.
[0044] Particularly in the CDMA cellular system, because three base stations transmit signals, using the same frequency band, the terminal (mobile station) MS can receive signals from the three base stations simultaneously by observing only one frequency and changing the signal pattern to watch.
[0045] [0045]FIG. 3 shows delay profiles of measured signals received from a plurality of stations when the MS is near a repeater.
[0046] As described in the “Description of Related Art” part of this specification, a delayed signal from the repeater RP is received as the signal of more intensive power than the signal directly transmitted from the base station BS 1 . If the signal from the repeater is used as is for position calculation, this considerably delayed signal causes a large error of the terminal position obtained as the solution of the equations for position calculation (FIG. 2), that is, the obtained position is largely off the true position of the terminal.
[0047] [0047]FIG. 4 is a flowchart illustrating a position calculation method (Embodiment 1) that is implemented by the wireless communications terminal apparatus of embodiment of the invention. This flowchart illustrates the above method that is applied to, particularly, such terminal apparatus including means for detecting a repeater.
[0048] Prior to position calculation, the terminal determines whether a repeater or a base station from which it received the signals ( 101 ) If a repeater is detected, the terminal removes distance measurement obtained as the result of measuring delay time of the signals from the repeater ( 102 ). Then, the terminal calculates its position ( 103 ). Unless a repeater is detected, the terminal calculates its position, using distance measurements obtained as the result of measuring delay time of the signals from all base stations in its vicinity ( 103 ). The calculated terminal position is output ( 104 ).
[0049] The algorithm for detecting a repeater and removing the distance measurement of the repeater is very simple and its addition does not severely increase the position calculation load on the terminal. Therefore, the influence of a repeater on position calculation can be removed by simple decision.
[0050] A repeater detection method will then be explained.
[0051] [0051]FIG. 5 is a flowchart illustrating the repeater detection method applicable to Embodiment 1 of the invention.
[0052] Information as to whether a repeater exists that is connected to a base station is stored in the storage 7 of the terminal. By looking through this information table stored, the terminal determines whether a repeater exists that is connected to a base station located in the vicinity of the terminal ( 111 ). If a repeater connected to a transmitting base station exists, there is a possibility that the terminal receives signals from the repeater. The terminal compares the delay (delay time) of signals from the possible repeater and the delay of signals from another base station ( 112 ). If propagation distance obtained by multiplying the delay by light velocity for the signals from both is significantly longer than the distance between both base stations, it is determined that the terminal receives signals from the repeater ( 113 ). Determining whether the propagation distance is significantly longer than the distance between base stations depends on what intervals at which base stations are installed in the wireless communications system in which the terminal is used. Base stations are normally installed at intervals of several kilometers. Moreover, from the delay measurements in the wireless communications system in practical use (see FIG. 3), it is found that repeater delay occurs as delay equivalent to 12 km that is difference between the distance of the terminal from the repeater obtained from the measured delay time of signals from the repeater and the distance of the terminal from the base station that uses the repeater for transmitting the signals from it. In view hereof, a threshold for determination should be set at, for example, double the average interval between base stations. By comparing the delay with the threshold, if the delay is less than the threshold, it is determined that the possible repeater is not a repeater ( 114 ). This embodiment of the repeater detection method may be modified to determine whether a repeater or a base station from which the terminal receives signals by time difference of signal arrival before multiplying the delay by light velocity, not based on distance difference between a base station and its repeater.
[0053] In the above-described repeater detection method (FIG. 5), repeater detection is conditioned in the step 111 in which the terminal looks through the information table and determines whether a repeater exists that is connected to a base station in the vicinity of the terminal when determining whether a repeater or a base station from which it receives signals. However, even if such conditioning is excluded, this repeater detection method is effective. That is, even if determination is not made as to possibility of a repeater existing near the terminal, when the delay of signals from a transmitting station is significantly longer than the delay of signals from other base stations, it is obvious that the transmitting station is a repeater. Thus, even if determination in the step 111 is omitted, the repeater detection method illustrated in FIG. 5 remains effective. However, when the terminal is at high place such as the top of a mountain where it can receive radio waves from a far transmitter or when base stations are installed densely and recurrent PN offset signals are transmitted over a short distance, the terminal may receive signals of long delay from a far base station, which may cause an error of positional calculation. When the step 111 is executed and the terminal determines that a possible repeater exists near the terminal, the terminal removes inconsistent measurement and this is also effective for preventing the error that may occur in the above situation.
[0054] Another embodiment of the invention will now be described. In the above-described Embodiment 1 (FIG. 4), terminal position calculation is executed without using the measurement of distance of the terminal from the possible repeater. However, when the terminal is very near to a repeater, the terminal receives signals of highly intensive power from the repeater as described above. At this time, automatic gain control (AGC) is activated in the RF unit 2 of the terminal to suppress signals from other base stations and consequently it may be difficult to observe the signals from other base stations. Especially, in closed space such as indoor environment, transmission loss occurs when the signals from other base stations pass through walls, which makes reception of those signals more difficult, greatly affecting the result of observation of the signals from base stations. In this case, it is effective to use a position calculation method in which the terminal position is regarded as the repeater location if the terminal is very near to the repeater.
[0055] [0055]FIG. 6 a flowchart illustrating another position calculation method (Embodiment 2) that is implemented by the wireless communications terminal apparatus of embodiment of the invention.
[0056] Based on the measurements of propagation delay time of signals from the base stations in the vicinity of the terminal, the terminal first determines whether signals from a repeater are observed ( 201 ). Determining whether the terminal receives signals from a repeater is done by the above-described method illustrated in FIG. 5. If a repeater is detected, the terminal determines whether the repeater is a base station from which it received a sync channel, in other words, whether the base station outputting the most powerful signals received by the terminal is the repeater ( 202 ).
[0057] If it is determined that the base station transmitting the sync channel is the repeater, the terminal determines the repeater location as its position because the repeater is located very near to the terminal (reception point) ( 203 ). If it is determined that the base station transmitting the sync channel is not the repeater, the terminal removes distance measurement obtained as the result of measuring delay time of the signals from the repeater ( 204 ) and calculates its position ( 205 ). Finally, the terminal position determined through the step 203 or step 205 is output ( 206 ).
[0058] If no repeater is detected in the step 201 , the terminal calculates its position, using distance measurements obtained as the result of measuring delay time of the signals from all base stations in its vicinity ( 205 ) While, in Embodiment 2 described above, the terminal determines whether a repeater exists in its vicinity by the above-described method illustrated in FIG. 5, it can make this determination, using another method, when the repeater is the station transmitting the sync channel.
[0059] [0059]FIG. 7 is a flowchart illustrating another repeater detection method applicable to Embodiment 2 of the invention.
[0060] By looking through a list of repeaters stored in the storage 7 of the terminal, the terminal first determines whether a repeater exists that is connected to a base station located in the vicinity of the terminal ( 211 ). If there is no possibility of a repeater existing near the terminal, the terminal determines that the transmitting station is not a repeater.
[0061] If there is a possibility of a repeater existing near the terminal, the terminal determines whether the base station transmitting PN offset signals is the one from which it received the sync channel, in other words, whether it is the one transmitting the highest power signals ( 212 ). A method of determining whether the station is transmitting the sync channel will be described later, using FIG. 9. If the base station transmitting PN offset signals is the one from which the terminal received the sync channel, the terminal determines whether it can detect other sector signals ( 213 ).
[0062] If the terminal can observe only the sector of sync channel, it determines that the transmitting station is a repeater ( 214 ). If the terminal can observe other sectors, it determines that the transmitting station is not a repeater ( 216 ).
[0063] If it is determined that the base station transmitting PN offset signals is not the one from which the terminal received the sync channel in the step 212 , the terminal cannot determine whether the transmitting station is a repeater by this method ( 215 ). In this case where decision is impossible, the method illustrated in FIG. 5 can be used to supplement such decision, and using the described methods in combination is embraced in the range of the invention.
[0064] The principle of determining whether a repeater or a base station from which the terminal receives signals by observing the number of sectors it receives will now be described, using FIG. 8.
[0065] In order to increase frequency use efficiency, a cellular base station normally transmits signals in sectors of a frequency band, using a directional antenna. Because the FB fractions provided by the antenna are about 20 dB, when the terminal is very near to a base station, it observes a plurality of sectors (for example, 3 sectors), not only one sector. On the other hand, a repeater simply repeats signals in one of the sectors from a base station. When the terminal is very near to a repeater, in most cases, it observes signals in one sector, not in plurality of sectors.
[0066] This is also due to AGC (Automatic Gain Control) on the terminal. The terminal is provided with the AGC function that adjusts the input end amplifier to gain constant average power of signals received. When the terminal is very near to a base station or repeater, it receives powerful signals from the station. Consequently, the AGC is activated to reduce the gain of the amplifier, which makes an adjustment of signal power to prevent signal power saturation. Adversely, the receiver sensitivity decreases, and the terminal becomes unable to receive signals of low power. Thus, the terminal becomes unable to receive signals from far base stations. When the terminal is very near to a base station, it receives signals in other sectors satisfactorily because these signals are also sufficiently powerful even if the terminal receiver sensitivity decreases. On the other hand, when the terminal is very near to a repeater, it receives dominant signals in one sector because the repeater repeats signals in only one sector, which causes the AGC to operate. Signals in other sectors from a far station become hard to be received by the terminal in the condition that the receiver sensitivity decreases.
[0067] Taking advantage of the above receiving characteristics of the terminal, the terminal detects a repeater in the step 213 in FIG. 7 by determining whether it can detect signals in other sectors from the transmitting station.
[0068] [0068]FIG. 8 is a graph of delay profiles of measured pilot signals from base stations and a repeater in the vicinity of the terminal when the terminal is very near to the repeater. In this chart, delay time increases along the abscissa, that is, a signal plotted nearer to the right end is of longer delay. The power intensity of a signal received at the delay time is plotted along the ordinate. In the vicinity of the terminal location of measurement, there are four base stations: base station 0 transmitting signals in sectors PN 01 , PN 02 , and PN 03 ; base station 1 transmitting signals in sectors PN 11 , PN 22 , and PN 13 , base station 2 transmitting signals in sectors PN 21 ; PN 22 , and PN 23 , and base stations 4 transmitting signals in sectors PN 31 ; PN 32 , and PN 33 . At the point of observation, the terminal receives pilot signals from these base stations, the pilot signals being offset in accordance with the pilot PN offset predetermined for each base station.
[0069] In the chart, apparent peaks of six sector signals PN 01 , PN 11 , PN 12 , PN 21 , PN 31 , and PN 33 can be observed. A base station outputting the highest signal power is the one transmitting PN 01 , PN 02 , and PN 03 sector signals. However, only the PN 01 signal can be observed and the remaining PN 02 and PN 03 signals cannot be observed. This phenomenon is characteristic of reception of signals from a repeater as described above. Thus, it can be determined that the base station 0 from which the terminal receives only the PN 01 sector signal is a repeater.
[0070] [0070]FIG. 9 is a flowchart illustrating a sync channel detection method which is applied to the repeater detection method (FIG. 7) of embodiment of the invention.
[0071] As described above, a feature of the sync channel is the highest power signal received. Thus, the terminal first compares the signal power received from the station and the signal level received from other stations and determines whether the most powerful signal is received from the station ( 221 ). The terminal determines that the station is transmitting the sync channel if the most powerful signal is received from the station ( 222 ). If not, the terminal determines that the station is not transmitting the sync channel ( 223 ).
[0072] [0072]FIG. 10 is a block diagram showing the configuration of a system for determining wireless terminal position.
[0073] While, in the above-described embodiment, the information table used for the terminal to determine whether a repeater exists that is connected to a base station is stored in the storage 7 of the terminal, a system can be configured so that the terminal can use such information stored into a database outside the terminal.
[0074] In the system for determining wireless terminal position shown in FIG. 10, the list of base stations and associated repeaters is stored on a server apparatus connected to the wireless communications network. The terminal sends a base station ID received from a base station nearest to it to the server via a base station BS 3 . The server searches out the base station ID that the terminal received, retrieves the IDs of its neighboring base stations, their PN offsets, and locations from the information table, and sends back them to the terminal. Using the information provided by the server, the terminal observes the base stations and the PN offset signals transmitted from them. Using the distance measurements obtained from the observed signals, the terminal carries out the repeater detection method of the above-described embodiment.
[0075] In this case, the terminal may calculate its position. Instead, it is also preferable to send the distance measurements of the terminal and the base stations in its vicinity, calculated from the delay profiles to the server via the wireless communications network so that the server will calculate the terminal position.
[0076] According to other aspects of the invention than claimed, typical embodiments of the invention are enumerated below.
[0077] (1) A wireless communications terminal apparatus in which the storage means stores the identifiers of base stations with an indicator per base station indicating whether a repeater is connected to the base station as base stations information.
[0078] (2) A system for determining terminal position in which repeater detection means compares timing of receiving a signal from a radio station and timing of receiving a signal from another radio station and determines that the radio station is a repeater, based on the result of the comparison (for example, when the timing of receiving the signal from the radio station is later than the timing of receiving the signal from another radio station by a predetermined time and longer).
[0079] (3) A system for determining terminal position in which, when the terminal can observe signals only in a predetermined number of sectors from one of the radio stations, the repeater detection means determines that the one of the radio stations is a repeater.
[0080] (4) A system for determining terminal position in which the repeater detection means determines whether a signal having the maximum power or amplitude among the received signals was received from a repeater.
[0081] (5) A system for determining terminal position including storage means for storing information as to whether a repeater exists that is connected to a radio station, wherein the repeater detection means determines whether there is a possibility of receiving signals from a repeater, using repeater-related information stored in the storage means, and detects a repeater if there is a possibility of receiving signals from a repeater.
[0082] (6) A position calculation method including the repeater detection step which comprises the step of determining whether a signal having the maximum power or amplitude among the received signals was received from a repeater.
[0083] (7) A position calculation method including the repeater detection step which comprises the steps of determining whether there is a possibility of receiving signals from a repeater, using information as to whether a repeater exists that is connected to a radio station, which was stored in the storage means, and detecting a repeater if there is a possibility of receiving signals from a repeater.
[0084] (8) A position calculation method including the repeater detection step which comprises the steps of obtaining repeater-related information stored in storage facilities connected to a wireless communications network from the storage facilities, determining whether there is a possibility of receiving signals from a repeater, using the thus obtained information, and detecting a repeater if there is a possibility of receiving signals from a repeater.
[0085] (9) A position calculation method including a reception timing measuring step for receiving a signal transmitted from a radio station and measuring its reception timing and a reception timing sending step for sending the measured reception timing to a server apparatus connected to the wireless communications network via a wireless communication line and the repeater detection step which comprises the step of determining whether a repeater exists that is connected to the radio station that transmitted the signal received, based on its reception timing which was sent to the server.
[0086] (10) A server apparatus in which the repeater detection means compares timing of receiving a signal from a radio station and timing of receiving a signal from another radio station and determines that the radio station is a repeater, based on the result of the comparison (for example, when the timing of receiving the signal from the radio station is later than the timing of receiving the signal from another radio station by a predetermined time and longer).
[0087] (11) A server apparatus in which, when the terminal can observe signals only in a predetermined number of sectors from one of the radio stations, the repeater detection means determines that the one of the radio stations is a repeater.
[0088] (12) A server apparatus in which the repeater detection means determines whether a signal having the maximum power or amplitude among the received signals was received from a repeater.
[0089] (13) A server apparatus including storage means for storing information as to whether a repeater exists that is connected to a radio station, wherein the repeater detection means determines whether there is a possibility of receiving signals from a repeater, using repeater-related information stored in the storage means, and detects a repeater if there is a possibility of receiving signals from a repeater.
[0090] (14) A server apparatus in which the storage means stores the identifiers of base stations with an indicator per base station indicating whether a repeater is connected to the base station as base stations information.
[0091] (15) An apparatus fabricated with semiconductor integrated circuits on which the repeater detection step is executed, the repeater detection step comprising the steps of comparing timing of receiving a signal from a radio station and timing of receiving a signal from another radio station and determining that the radio station is a repeater, based on the result of the comparison (for example, when the timing of receiving the signal from the radio station is later than the timing of receiving the signal from another radio station by a predetermined time and longer).
[0092] (16) An apparatus fabricated with semiconductor integrated circuits on which the repeater detection step is executed, wherein, when the terminal can observe signals only in a predetermined number of sectors from one of the radio stations, the repeater detection step determines that the one of the radio stations is a repeater.
[0093] (17) An apparatus fabricated with semiconductor integrated circuits on which the repeater detection step is executed to determine whether a signal having the maximum power or amplitude among the received signals was received from a repeater.
[0094] (18) An apparatus fabricated with semiconductor integrated circuits on which the repeater detection step is executed to determine whether there is a possibility of receiving signals from a repeater, using information as to whether a repeater exists that is connected to a radio station, stored in the storage means, and detect a repeater if there is a possibility of receiving signals from a repeater.
[0095] (19) An apparatus fabricated with semiconductor integrated circuits on which the repeater detection step is executed, the repeater detection step comprising the steps of obtaining repeater-related information stored in storage facilities connected to a wireless communications network from the storage facilities, determining whether there is a possibility of receiving signals from a repeater, using the thus obtained information, and detecting a repeater if there is a possibility of receiving signals from a repeater.
[0096] (20) An apparatus fabricated with semiconductor integrated circuits on which a reception timing measuring step for receiving a signal transmitted from a radio station and measuring its reception timing and a reception timing sending step for sending the measured reception timing to a server apparatus connected to the wireless communications network via a wireless communication line are executed together with the repeater detection step which comprises the step of determining whether a repeater exists that is connected to the radio station that transmitted the signal, based on its reception timing which was sent to the server. | The disclosed invention provides a wireless communications terminal apparatus that calculates its accurate position, eliminating the influence of a repeater on the calculation without using complicated processing. The terminal apparatus receives signals transmitted from a plurality of radio stations and calculates its position, using the received signals. The terminal apparatus comprises repeater detection means for detecting a signal from a repeater which transmits signals that are generated on the basis of signals transmitted from one of the radio stations and indistinguishable from the signals transmitted from that radio station from among the received signals and position calculation means for calculating its position. When the repeater detection means has detected a signal from a repeater, the position calculation means ignores the detected signal from the repeater and calculates the terminal position, using the received signals from other radio stations. | 6 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to electrostatic dissipative polymers and blends, including thermoplastic urethanes (TPU) containing compositions.
[0002] The formation and retention of charges of static electricity on the surface of most plastics is well known. Plastic materials have a significant tendency to accumulate static electrical charges due to low electrical conductivity. This type of formation and retention of charges of static electricity can be problematic. The presence of static electrical charges on sheets of thermoplastic film, for example, can cause the sheets to adhere to one another thus making their separation for further processing more difficult. Moreover, the presence of static electrical charges causes dust to adhere to items packaged in a plastic bag, for example, which may negate any sales appeal.
[0003] The increasing complexity and sensitivity of microelectronic devices makes the control of static discharge of particular concern to the electronics industry. Even a low voltage discharge can cause severe damage to sensitive devices. The need to control static charge buildup and dissipation often requires the entire assembly environment for these devices to be constructed of partially conductive materials. It also may require that electrostatic protective packages, tote boxes, casings, and covers be made from conductive polymeric materials to store, ship, protect, or support electrical devices and equipment.
[0004] The prevention of the buildup of static electrical charges which accumulate on plastics during manufacture or use has been accomplished by the use of various electrostatic dissipative (ESD) materials. These materials can be applied as a coating which may be sprayed or dip coated on the article after manufacture, although this method usually results in a temporary solution. Alternatively, these materials can be incorporated into a polymer used to make the article during processing, thereby providing a greater measure of permanence.
[0005] However, the incorporation of these lower molecular weight electrostatic dissipative materials (antistatic agents) into the various matrix or base polymers has its own limitations. For example, the high temperatures required for conventional processing of most polymers may damage or destroy the antistatic agents, thereby rendering them useless with respect to their ESD properties. Moreover, many of the higher molecular weight ESD agents are not miscible with the matrix or base polymers employed. In addition, the use of antistatic agents may only provide short term ESD properties to the compositions in which they are used. Their performance and effectiveness is also often impacted by humidity. There is a need to provide good ESD properties without these drawbacks and limitations.
[0006] Furthermore, a large number of antistatic agents are also either cationic or anionic in nature. These agents tend to cause the degradation of plastics, particularly PVC, and result in discoloration or loss of physical properties. Other antistatic agents have significantly lower molecular weights than the base polymers themselves. Often these lower molecular weight antistatic agents possess undesirable lubricating properties and are difficult to incorporate into the base polymer. Incorporation of the lower molecular weight antistatic agents into the base polymers often will reduce the moldability of the base polymer because the antistatic agents can move to the surface of the plastic during processing and frequently deposit a coating on the surface of the molds, possibly destroying the surface finish on the articles of manufacture. In severe cases, the surface of the article of manufacture becomes quite oily and marbleized. Additional problems which can occur with lower molecular weight ESD agents are loss of their electrostatic dissipative capability due to evaporation, the development of undesirable odors, or promotion of stress cracking or crazing on the surface of an article in contact with the article of manufacture.
[0007] One of the known lower molecular weight antistatic agents is a homopolymer or copolymer oligomer of ethylene oxide. Generally, use of the lower molecular weight polymers of ethylene oxide or polyethers as antistatic agents are limited by the above-mentioned problems relative to lubricity, surface problems, or less effective ESD properties. Further, these low molecular weight polymers can be easily extracted or abraded from the base polymer thereby relinquishing any electrostatic dissipative properties, and in some instances can also produce undesirably large amounts of unwanted extractable anions, and in particular chloride, nitrate, phosphate, and sulfate anions.
[0008] There are several examples of high molecular weight electrostatic dissipative agents in the prior art. In general, these additives have been high molecular weight polymers of ethylene oxide or similar materials such as propylene oxide, epichlorohydrin, glycidyl ethers, and the like. It has been a requirement that these additives be high molecular weight materials to overcome the problems mentioned above. However, these prior art ESD additives do not have a desired balance between electrical conductivity and acceptable low levels of extractable anions and/or cations, in particular, chloride, fluoride, bromide, nitrate, phosphate, sulfate and ammonium, which in turn can cause any manufactured articles containing such ESD additives to have unacceptable properties for some end uses.
[0009] For example, U.S. Pat. No. 6,140,405 provides polymers for use with electronic devices, and specifically polymers containing a halogen-containing salt for electrostatic dissipation. These polymers balance the electrical conductivity and acceptable low levels of extractable anions and/or cations, however, they do this by using a halogen-containing ESD additive.
[0010] There is also continued pressure to reduce the presence of halogens in general, both in articles and generally in the environment. As many ESD additives contain halogens, the drive to reduce and/or eliminate halogen content creates difficulties when trying to maintain the ESD properties needed in many applications. The present invention provides a halogen-free ESD additive that provides good ESD performance while allowing for the reduction and/or elimination of halogen content in ESD materials. The present invention also overcomes one or more of the other problems associated with conventional ESD additives discussed above.
[0011] The present invention solves the problem of obtaining electrostatic dissipative polymers or additives which exhibit relatively low surface and volume resistivities without unacceptably high levels of extractable anions, in particular, chloride, nitrate, phosphate, and sulfate anions. These electrostatic dissipative polymers in turn can be incorporated in base polymer compositions useful in the electronics industry without producing other undesirable properties in a finished article of manufacture.
SUMMARY OF THE INVENTION
[0012] The present invention provides a composition comprising: (a) an inherently dissipative polymer and (b) a halogen-free lithium-containing salt. In some embodiments, the halogen-free lithium-containing salt comprises a salt with the formula:
[0000]
[0013] wherein each —X 1 —, —X 2 —, —X 3 — and —X 4 — is independently —C(O)—, —C(R 1 R 2 )—, —C(O)—C(R 1 R2)— or —C(R 1 R2)—C(R 1 R 2 )— where each R 1 and R 2 is independently hydrogen or a hydrocarbyl group and wherein the R 1 and R 2 of a given X group may be linked to form a ring.
[0014] The halogen-free lithium-containing salt may also comprise a salt with the formula:
[0000]
[0000] wherein each —X 1 —, —X 2 —, —X 3 — and —X 4 — is independently —C(O)R 1 , —C(R 1 R 2 R 3 ), —C(O)— —C(R 1 R 2 R 3 ) or —C(R 1 R2)— —C(R 1 R 2 R 3 ) where each R 1 and R 2 and R 3 is independently hydrogen or a hydrocarbyl group and wherein the R 1 , R 2 and/or R 3 of a given X group may be linked to form a ring. In still further embodiments, the salt may be partially closed, that is groups X 1 and X 2 may be linked as they are in formula (I), having the definitions presented under formula (I), while groups X 3 and X 4 are not linked, as they are in formula (II), and having the definitions presented under formula (II).
[0015] In some embodiments, the inherently dissipative polymer comprises a thermoplastic elastomer and may also be a blend of at least two polymers. The thermoplastic elastomer may be a thermoplastic urethane, a copolyamide, copolyester ethers, polyolefin polyether copolymers, or combinations thereof.
[0016] The invention also provides a shaped polymeric article comprising the inherently dissipative polymer compositions described herein.
[0017] The invention also provides a process of making the inherently dissipative polymer compositions described herein. The process includes the step of mixing a halogen-free lithium-containing salt into an inherently dissipative polymer.
[0018] The compositions of the invention may have a surface resistivity of from about 1.0'10 6 ohm/square to about 1.0×10 12 or about 1.0×10 10 ohm/square as measured by ASTM D-257, and further the compositions may have less than about 8,000 parts per billion total extractable anions measured from the group of all four of chloride anions, nitrate anions, phosphate anions, and sulfate anions, and less than about 1,000 parts per billion of said chloride anions, less than about 100 parts per billion of said nitrate anions, less than about 6,000 parts per billion of said phosphate anions, and less than about 1,000 parts per billion of said sulfate anions.
DETAILED DESCRIPTION OF THE INVENTION
[0019] Various features and embodiments of the invention will be described below by way of non-limiting illustration.
The Inherently Dissipative Polymer
[0020] The compositions of the present invention include an inherently dissipative polymer. That is a polymer that has electrostatic dissipative (ESD) properties. In some embodiments, the polymer comprises a thermoplastic elastomer. Such materials may be generally described as polymers having in their backbone structures hard and/or crystalline segments and/or blocks in combination with soft and/or rubbery segments and/or blocks.
[0021] In some embodiments, the inherently dissipative polymer includes a thermoplastic polyurethane (TPU), a polyolefin polyether copolymer, a thermoplastic polyester elastomer (COPE), a polyether block amide elastomer (COPA or PEBA), or a combination thereof. Examples of suitable copolymers include polyolefin-polyether copolymers.
[0022] In some embodiments, the thermoplastic polyurethane is made by reacting at least one polyol intermediate with at least one diisocyanate and at least one chain extender. The polyol intermediate may be a polyether polyol and may be derived from at least one dialkylene glycol and at least one dicarboxylic acid, or an ester or anhydride thereof. The polyol intermediate may be a polyalkylene glycol and/or a poly(dialkylene glycol ester). Suitable polyalkylene glycols include polyethylene glycol, polypropylene glycol, polyethyleneglycol-polypropylene glycol copolymers, and combinations thereof. The polyol intermediate may also be a mixture of two or more different types of polyols. In some embodiments, the polyol intermediate includes a polyester polyol and a polyether polyol.
[0023] The polymer component may also be a blend of two or more polymers. Suitable polymers for use in such blends include any of the polymers described above. Suitable polymers also include a polyester-based TPU, a polyether-based TPU, a TPU containing both polyester and polyether groups, a polycarbonate, a polyolefin, a styrenic polymer, an acrylic polymer, a polyoxymethylene polymer, a polyamide, a polyphenylene oxide, a polyphenylene sulfide, a polyvinylchloride, a chlorinated polyvinylchloride or combinations thereof.
[0024] Suitable polymers for use in the blends described herein include homopolymers and copolymers. Suitable examples include:
[0025] (i) a polyolefin (PO), such as polyethylene (PE), polypropylene (PP), polybutene, ethylene propylene rubber (EPR), polyoxyethylene (POE), cyclic olefin copolymer (COC), or combinations thereof;
[0026] (ii) a styrenic, such as polystyrene (PS), acrylonitrile butadiene styrene (ABS), styrene acrylonitrile (SAN), styrene butadiene rubber (SBR or HIPS), polyalphamethylstyrene, styrene maleic anhydride (SMA), styrene-butadiene copolymer (SBC) (such as styrene-butadiene-styrene copolymer (SBS) and styrene-ethylene/butadiene-styrene copolymer (SEBS)), styrene-ethylene/propylene-styrene copolymer (SEPS), styrene butadiene latex (SBL), SAN modified with ethylene propylene diene monomer (EPDM) and/or acrylic elastomers (for example, PS-SBR copolymers), or combinations thereof;
[0027] (iii) a thermoplastic polyurethane (TPU);
[0028] (iv) a polyamide, such as Nylon™, including polyamide 6,6 (PA66), polyamide 11 (PA11), polyamide 12 (PA12), a copolyamide (COPA), or combinations thereof;
[0029] (v) an acrylic polymer, such as polymethyl acrylate, polymethylmethacrylate, a methyl methacrylate styrene (MS) copolymer, or combinations thereof;
[0030] (vi) a polyvinylchloride (PVC), a chlorinated polyvinylchloride (CPVC), or combinations thereof;
[0031] (vii) a polyoxyemethylene, such as polyacetal;
[0032] (viii) a polyester, such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), copolyesters and/or polyester elastomers (COPE) including polyether-ester block copolymers such as glycol modified polyethylene terephthalate (PETG) polylactic acid (PLA), or combinations thereof;
[0033] (ix) a polycarbonate (PC), a polyphenylene sulfide (PPS), a polyphenylene oxide (PPO), or combinations thereof;
[0034] or combinations thereof.
[0035] Polyvinyl chloride (PVC), vinyl polymer, or vinyl polymer material, as used herein, refers to homopolymers and copolymers of vinyl halides and vinylidene halides and includes post halogenated polyvinyl halides such as CPVC. Examples of these vinyl halides and vinylidene halides are vinyl chloride, vinyl bromide, vinylidene chloride and the like. The vinyl halides and vinylidene halides may be copolymerized with each other or each with one or more polymerizable olefinic monomers having at least one terminal CH 2 =C<grouping. As examples of such olefinic monomers there may be mentioned the alpha,beta-olefinically unsaturated carboxylic acids, such as acrylic acid, methacrylic acid, ethyl acrylic acid, alpha-cyano acrylic acid, and the like; esters of acrylic acid, such as methyl acrylate, ethyl acrylate, butyl acrylate, octyl acrylate, ethyl-cyano acrylate, hydroxyethyl acrylate, and the like; esters of methacrylic acid, such as methyl methacrylate, butyl methacrylate, hydroxyethyl methacrylate, and the like; nitriles, such as acrylonitrile, methacrylonitrile, and the like; acrylamides, such as methyl acrylamide, N-methylol acrylamide, N-butoxy methylacrylamide, and the like; vinyl ethers, such as ethyl vinyl ether, chloro ethyl vinyl ether, and the like; the vinyl ketones; styrene and styrene derivatives, such as alpha-methyl styrene, vinyl toluene, chlorostyrene, and the like; vinyl naphthalene, allyl and vinyl chloroacetate, vinyl acetate, vinyl pyridine, methyl vinyl ketone; the diolefins, including butadiene, isoprene, chloroprene, and the like; and other polymerizable olefinic monomers of the types known to those skilled in the art. In one embodiment, the polymer component includes polyvinyl chloride (PVC) and/or polyethylene terephthalate (PET).
[0036] Polymers suitable for use in the compositions of the present invention may also be described as polymers derived from low molecular weight polyether oligomers, wherein the polymers display relatively low surface and volume resistivities, yet generally are free of excessive levels of extractable anions.
[0037] The low molecular weight polyether oligomer useful in the present invention can comprise a homopolymer of ethylene oxide having a number average molecular weight of from about 200 to about 5000. The low molecular weight polyether oligomer can also comprise a copolymer of two or more copolymerizable monomers wherein one of the monomers is ethylene oxide and has a number average molecular weight from about 200 to about 20,000.
[0038] Exemplary of the comonomers which can be copolymerized with ethylene oxide are: 1,2-epoxypropane(propylene oxide); 1,2-epoxybutane; 2,3-epoxybutane(cis & trans); 1,2-epoxypentane; 2,3-epoxypentane(cis & trans); 1,2-epoxyhexane; 2,3-epoxyhexane(cis & trans); 3,4-epoxyhexane(cis & trans); 1,2-epoxy heptane; 1,2-epoxydecane; 1,2-epoxydodecane; 1,2-epoxyoctadecane; 7-ethyl-2-methyl-1,2-epoxyundecane; 2,6,8-trimethyl-1,2-epoxynonane; styrene oxide.
[0039] Other comonomers which can be used as comonomers with the ethylene oxide are: cyclohexene oxide; 6-oxabicyclo [3,1,0]-hexane; 7-oxabicyclo[4,1,0]heptane; 3-chloro-1,2-epoxybutane; 3-chloro-2,3-epxybutane; 3,3-dichloro-1,2-epoxypropane; 3,3,3-trichloro-1,2-epoxypropane; 3-bromo-1-2-epoxybutane, 3-fluoro-1 ,2-epoxybutane; 3-iodo-1 ,2-epoxybutane; 1,1-dichloro-1-fluoro-2,3-epoxypropane; 1-chloro-1,1-dichloro-2,3-epoxypropane; and 1,1,1,2-pentachloro-3 ,4-epoxybutane.
[0040] Typical comonomers with at least one ether linkage useful as co-monomers are exemplified by: ethyl glycidyl ether; n-butyl glycidyl ether; isobutyl glycidyl ether; t-butyl glycidyl ether; n-hexyl glycidyl ether; 2-ethylhexyl glycidyl ether; heptafluoroisopropyl glycidyl ether, phenyl glycidyl ether; 4-methyl phenyl glycidyl ether; benzyl glycidyl ether; 2-phenylethyl glycidyl ether; 1,2-dihydropentafluoroisopropyl glycidyl ether; 1,2-trihydrotetrafluoroisopropyl glycidyl ether; 1,1-dihydrotetrafluoropropyl glycidyl ether; 1,1-dihydranonafluoropentyl glycidyl ether; 1,1-dihydropentadecafluorooctyl glycidyl ether; 1,1-dihydropentadecafluorooctyl-alpha-methyl glycidyl ether; 1,1-dihydropentadecafluorooctyl-beta-methyl glycidyl ether; 1,1-dihydropentadecafluorooctyl-alpha-ethyl glycidyl ether; 2,2,2-trifluoro ethyl glycidyl ether.
[0041] Other comonomers with at least one ester linkage which are useful as comonomers to copolymerize with ethylene oxide are: glycidyl acetate; glycidyl chloroacetate; glycidyl butyrate; and glycidyl stearate; to name a few.
[0042] Typical unsaturated comonomers which can be polymerized with ethylene oxide are: allyl glycidyl ether; 4-vinylcyclohexyl glycidyl ether; alpha-terpinyl glycidyl ether; cyclohexenylmethyl glycidyl ether; p-vinylbenzyl glycidyl ether; allyphenyl glycidyl ether; vinyl glycidyl ether; 3,4-epoxy-1-pentene; 4,5-epoxy-2-pentene; 1,2-epoxy-5,9-cyclododecadiene; 3,4-epoxy-1-vinylchlohexene; 1,2-epoxy-5-cyclooctene; glycidyl acrylate; glycidyl methacrylate; glycidyl crotonate; glycidyl 4-hexenoate.
[0043] Other cyclic monomers suitable to copolymerize with ethylene oxide are cyclic ethers with four or more member-ring containing up to 25 carbon atoms except tetrahydropyran and its derivatives. Exemplary cyclic ethers with four or more member-ring are oxetane (1,3-epoxide), tetrahydrofuran (1,5-epoxide), and oxepane (1,6-epoxide) and their derivatives.
[0044] Other suitable cyclic monomers are cyclic acetals containing up to 25 carbon atoms. Exemplary cyclic acetals are trioxane, dioxolane, 1,3,6,9-tetraoxacycloundecane, trioxepane, troxocane, dioxepane and their derivatives.
[0045] Other suitable cyclic monomers are cyclic esters containing up to 25 carbon atoms. Exemplary cyclic esters are beta-valerolactone, epsilon-caprolactone, zeta-enantholactone, eta-capryllactone, butyrolactone and their derivatives. The low molecular weight polyether oligomer prepared by the method detailed immediately above then can be reacted with a variety of chain extenders and modified with a selected salt to form the electrostatic dissipative polymer additive or antistatic agent of the present invention.
[0046] A preferred embodiment of the polyester-ether block copolymer comprises the reaction product of ethylene glycol, terephthalic acid or dimethyl terephthalate and polyethylene glycol. These and other examples of other polyester-ether copolymers which can be utilized are set forth in the Encyclopedia of Polymer Science and Engineering, Vol. 12, John Wiley & Sons, Inc., NY, N.Y., 1988, pages 49-52, which is hereby fully incorporated by reference as well as U.S. Pat. Nos. 2,623,031; 3,651,014; 3,763,109; and 3,896,078.
[0047] Alternatively, the low molecular weight polyether oligomer can be reacted to form an electrostatic dissipative agent comprising one or more polyamide blocks as well as one or more low molecular weight polyether oligomer blocks. Alternatively, the low molecular weight polyether oligomer may be reacted with the polyamide in the presence of a diacid to form a polyether ester amide. Further information on this type of polymer can be found in U.S. Pat. No. 4,332,920.
[0048] Referring first to the polyester intermediate, a hydroxyl terminated, saturated polyester polymer is synthesized by reacting excess equivalents of diethylene glycol with considerably lesser equivalents of an aliphatic, preferably an alkyl, dicarboxylic acid having four to ten carbon atoms where the most preferred is adipic acid.
[0049] The hydroxyl terminated polyester oligomer intermediate is further reacted with considerably excess equivalents of non-hindered diisocyanate along with extender glycol in a so-called one-shot or simultaneous co-reaction of oligomer, diisocyanate, and extender glycol to produce the very high molecular weight linear polyurethane having an average molecular weight broadly from about 60,000 to about 500,000, preferably from about 80,000 to about 180,000, and most preferably from about 100,000 to about 180,000.
[0050] Alternatively, an ethylene ether oligomer glycol intermediate comprising a polyethylene glycol can be co-reacted with non-hindered diisocyanate and extender glycol to produce the high molecular weight, polyurethane polymer. Useful polyethylene glycols are linear polymers of the general formula H—(OCH 2 CH 2 ) n —OH where n is the number of repeating ethylene ether units and n is at least 11 and between 11 and about 115. On a molecular weight basis, the useful range of polyethylene glycols have an average molecular weight from about 500 to about 5000 and preferably from about 700 to about 2500. Commercially available polyethylene glycols useful in this invention are typically designated as polyethylene glycol 600, polyethylene glycol 1500, and polyethylene glycol 4000.
[0051] In accordance with this invention, high molecular weight thermoplastic polyurethanes are produced by reacting together preferably in a one-shot process the ethylene ether oligomer glycol intermediate, an aromatic or aliphatic non-hindered diisocyanate, and an extender glycol. On a mole basis, the amount of extender glycol for each mole of oligomer glycol intermediate is from about 0.1 to about 3.0 moles, desirably from about 0.2 to about 2.1 moles, and preferably from about 0.5 to about 1.5 moles. On a mole basis, the high molecular weight polyurethane polymer comprises from about 0.97 to about 1.02 moles, and preferably about 1.0 moles of non-hindered diisocyanate for every 1.0 total moles of both the extender glycol and the oligomer glycol (i.e., extender glycol+oligomer glycol-1.0).
[0052] Useful non-hindered diisocyanates comprise aromatic non-hindered diisocyanates and include, for example, 1,4-diisocyanatobenzene (PPDI), 4,4′-methylene-bis(phenyl isocyanate) MDI), 1,5-naphthalene diisocyanate (NDI), m-xylene diisocyanate (XDI), as well as non-hindered, cyclic aliphatic diisocyanates such as 1,4-cyclohexyl diisocyanate (CHDI), and H 12 MDI. The most preferred diisocyanate is MDI. Suitable extender glycols (i.e., chain extenders) are aliphatic short chain glycols having two to six carbon atoms and containing only primary alcohol groups. Preferred glycols include diethylene glycol, 1,3-propane diol, 1,4-butane diol, 1,5-pentane diol, 1,4-cyclohexane-dimethanol, hydroquinone di(hydroxyethyl)ether, and 1,6-hexane diol with the most preferred glycol being 1,4-butane diol.
[0053] In accordance with the present invention, the hydroxyl terminated ethylene ether oligomer intermediate, the non-hindered diisocyanate, and the aliphatic extender glycol are co-reacted simultaneously in a one-shot polymerization process at a temperature above about 100° C. and usually about 120° C., whereupon the reaction is exothermic and the reaction temperature is increased to about 200° C. to above 250° C.
The Halogen-Free Lithium-Containing Salt
[0054] The compositions of the present invention include halogen-free lithium-containing salt. In some embodiments, the salt is represented by the formula:
[0000]
[0000] wherein each —X 1 —, —X 2 —, —X 3 — and —X 4 — is independently —C(O)—, —C(R 1 R 2 )—, —C(O)—C(R 1 R 2 )— or —C(R 1 R 2 )—C(R 1 R 2 )— where each R 1 and R 2 is independently hydrogen or a hydrocarbyl group and wherein the R 1 and R 2 of a given X group may be linked to form a ring. In some embodiments the salt may be represented by formula (II) shown above, or any of the other embodiments described above.
[0055] In some embodiments, the salt is represent by Formula I wherein —X 1 —, —X 2 —, —X 3 — and —X 4 — are —C(O)—.
[0056] Suitable salts also include the open, -ate structures of such salts, including Lithium bis(oxalate)borate.
[0057] In some embodiments, the halogen-free lithium-containing salt comprises lithium bis(oxalato)borate, lithium bis(glycolato)borate, lithium bis(lactato)borate, lithium bis(malonato)borate, lithium bis(salicylate)borate, lithium (glycolato,oxalato) borate, or combinations thereof.
[0058] While the exact mechanism of attachment and/or attraction of the salt to the polymer reaction product is not completely understood, the salt can unexpectedly improve the surface and volume resistivities of the resulting polymer, and may accomplish this without the presence of unacceptably high levels of extractable anions. Moreover, the static decay times remain in an acceptable range, that is, the times are not too fast or too slow.
[0059] The compositions of the present invention may also contain one or more additional salts that are effective as an ESD additive. In some embodiments, these additional salts include metal-containing salts that contain a metal other than lithium. These additional salts may also include halogen-containing salts. Such salts include metal-containing salts, salt complexes, or salt compounds formed by the union of metal ion with a non-metallic ion or molecule. The amount of salt present may be an amount effective to provide improved ESD properties to the overall composition. The optional salt component may be added during the one-shot polymerization process.
[0060] Examples of additional salts useful in the present invention include: LiClO 4 , LiN(CF 3 SO 2 ) 2 , LiPF 6 , LiAsF 6 , LiI, LiCl, LiBr, LiSCN, LiSO 3 CF 3 , LiNO 3 , LiC(SO 2 CF 3 ) 3 , Li 2 S, and LiMR 4 , where M is Al or B, and R is a halogen, hydrocarbyl, alkyl or aryl group. In one embodiment, the salt is Li N(CF 3 SO 2 ) 2 , which is commonly referred to as lithium trifluoromethane sulfonamide, or the lithium salt of trifluoromethane sulfonic acid. The effective amount of the selected salt added to the one-shot polymerization may be at least about 0.10, 0.25, or even 0.75 parts by weight based on 100 parts by weight of the polymer.
[0061] In some embodiments, the compositions of the present invention further comprises a sulfonate-type anionic antistatic agent. Suitable examples include metal alkylsulfonates and metal alkyl-aromatic sulfonates. The metal alkylsulfonates can include alkali metal or alkaline earth metal aliphatic sulfonates in which the alkyl group has 1 to 35 or 8 to 22 carbon atoms. The alkali metals may include sodium and potassium and the alkaline earth metals may include calcium, barium and magnesium. Specific examples of metal alkylsulfonates include sodium n-hexylsulfonate, sodium n-heptylsulfonate, sodium n-octylsulfonate, sodium n-nonylsulfonate, sodium n-decylsulfonate, sodium n-dodecylsulfonate, sodium n-tetradecylsulfonate, sodium n-hexadecylsulfonate, sodium n-heptadecylsulfonate and sodium n-octadecylsulfonate. Specific examples of metal alkyl-aromatic sulfonates include alkali metal or alkaline earth metal salts of sulfonic acids comprising 1 to 3 aromatic nuclei substituted with an alkyl group having 1 to 35 or 8 to 22, carbon atoms. The aromatic sulfonic acids include, for example, benzenesulfonic, naphthalene-1-sulfonic, naphthalene-2,6-disulfonic, diphenyl-4-sulfonic and diphenyl ether 4-sulfonic acids. Metal alkyl-aromatic sulfonates include, for example, sodium hexylbenzenesulfonate, sodium nonylbenzenesulfonate and sodium dodecylbenzenesulfonate. In other embodiments, the compositions of the present invention are substantially free to free of sulfonate-type anionic antistatic agents.
[0062] The compositions of the present invention may also include an non-metal containing anti-stat additives, such as ionic liquids. Suitable liquids include tri-n-butylmethylammonium bis-(trifluoroethanesulfonyl)imide (available as FC-4400 from 3M™), one or more the Basionics™ line of ionic liquids (available from BASF™), and similar materials.
[0063] In some embodiments, the present invention allows for the use of co-solvent with the metal containing salt. The use of a co-solvent, may in some embodiments, allow a lower charge of salt to provide the same benefit in ESD properties. Suitable co-solvents include ethylene carbonate, propylene carbonate, dimethyl sulfoxide, tetramethylene sulfone, tri- and tetra ethylene glycol dimethyl ether, gamma butyrolactone, and N-methyl-2-pyrrolidone. When present, the co-solvent may be used at least about 0.10, 0.50 or even 1.0 parts by weight based on 100 parts by weight of the polymer. In some embodiments, the compositions of the present invention are substantially free to free of any or all of the co-solvents described herein.
[0064] In other embodiments, the compositions of the present invention are substantially free to free of any or all of the metal containing salts described herein and/or substantially free to free of any ESD additives except for the non-halogen lithium-containing salts described above.
[0065] The effective amount of the selected salt in the overall composition may be at least about 0.10 parts based on 100 parts of the polymer, and in some embodiments at least about 0.25 parts or even at least about 0.75 parts. In some embodiments, these amounts are with respect to each individual salt present in the composition. In other embodiments, the amounts apply to the total amount of all salts present in the composition.
Additional Additives
[0066] The compositions of the present invention may further include additional useful additives, where such additives can be utilized in suitable amounts. These optional additional additives include opacifying pigments, colorants, mineral and/or inert fillers, stabilizers including light stabilizers, lubricants, UV absorbers, processing aids, antioxidants, antiozonates, and other additives as desired. Useful opacifying pigments include titanium dioxide, zinc oxide, and titanate yellow. Useful tinting pigments include carbon black, yellow oxides, brown oxides, raw and burnt sienna or umber, chromium oxide green, cadmium pigments, chromium pigments, and other mixed metal oxide and organic pigments. Useful fillers include diatomaceous earth (superfloss) clay, silica, talc, mica, wallostonite, barium sulfate, and calcium carbonate. If desired, useful stabilizers such as antioxidants can be used and include phenolic antioxidants, while useful photostabilizers include organic phosphates, and organotin thiolates (mercaptides). Useful lubricants include metal stearates, paraffin oils and amide waxes. Useful UV absorbers include 2-(2′-hydroxyphenyl) benzotriazoles and 2-hydroxybenzophenones. Additives can also be used to improve the hydrolytic stability of the TPU polymer. Each of these optional additional additives described above may be present in, or excluded from, the compositions of the present invention.
[0067] When present, these additional additives may be present in the compositions of the present invention from 0 or 0.01 to 5 or 2 weight percent of the composition. These ranges may apply separately to each additional additive present in the composition or to the total of all additional additives present.
Industrial Application
[0068] The compositions described herein are prepared by mixing the halogen-free lithium-containing salt described above into the inherently dissipative polymer described above. In addition, one or more additional salts, polymers and/or additives may be present. The salt may be added to the polymer in various ways, some which may be defined as a chemical or in-situ process and some which may be defined as a physical or mixing process.
[0069] In some embodiments, the halogen-free lithium-containing salt is added to the inherently dissipative polymer during the polymerization of the polymer, resulting in the inherently dissipative polymer composition.
[0070] In some embodiments, the halogen-free lithium-containing salt is added to the inherently dissipative polymer via wet absorption, resulting in the inherently dissipative polymer composition.
[0071] In some embodiments, the halogen-free lithium-containing salt is compounded and/or blended into the inherently dissipative polymer, resulting in the inherently dissipative polymer composition.
[0072] The resulting compositions of the present invention include one or more of the inherently dissipative polymers described above in combination with one or more of the halogen-free lithium-containing salts described above. The compositions may include an effective amount of the salt, said salt being compatible with the polymer, such that the resulting composition has a surface resistivity of from about 1.0×10 6 ohm/square to about 1.0×10 10 ohm/square as measured by ASTM D-257, and further the salt-modified polymer having less than about 8,000 parts per billion total extractable anions measured from the group of all four of chloride anions, nitrate anions, phosphate anions, and sulfate anions, and less than about 1,000 parts per billion of said chloride anions, less than about 100 parts per billion of said nitrate anions, less than about 6,000 parts per billion of said phosphate anions, and less than about 1,000 parts per billion of said sulfate anions.
[0073] In some embodiments, the compositions of the present invention are substantially free to free of fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, astatine atoms, or combinations thereof (including ions of said atoms). In some embodiments, the compositions of the present invention are substantially free to free of salts and/or other compounds containing fluorine, chlorine, bromine, iodine, and/or astatine atoms, and/or ions of one or more thereof. In some embodiments, the compositions of the present invention are substantially free to free of all halogens atoms, halogen-containing salts, and/or other halogen-containing compounds. By substantially free, it is meant that the compositions contain less than 10,000 parts per million or even 10,000 parts per billion of fluorine/fluoride, chorine/chloride, bromine/bromide, iodine/iodide, astatine/astatide, or combinations of the atoms/ions thereof.
[0074] These polymer compositions are useful in forming a plastic alloy for use with an electronic device, due to their beneficial ESD and/or inherently dissipative properties. The compositions may be used in the preparation of polymeric articles, especially where ESD properties are of a concern. Examples of applications in which the compositions described above may be used building and construction materials and equipment, machine housings, manufacturing equipment, and polymeric sheets and films. More specifically, examples include: fuel handling equipment such as fuel lines and vapor return equipment; business equipment; coatings for floors such as for clean rooms and construction areas; clean room equipment such as garments, floorings, mats, electronic packaging, housings, chip holders, chip rails, tote bins and tote bin tops; medical applications; battery parts such as dividers and/or separators, etc. The compositions of the present invention may be used in any articles that require some level of ESD properties.
[0075] In one embodiment, the compositions of the present invention are used to make polymeric articles to be used as: packaging materials for electronic parts; internal battery separators for use in the construction of lithium-ion batteries; clean room supplies and construction materials; antistatic conveyor belts; fibers; parts for office machines; antistatic garments and shoes, or combinations thereof.
[0076] The compositions can be used with various melt processing techniques including injection molding, compression molding, slush molding, extrusion, thermoforming cast, rotational molding, sintering, and vacuum molding. Articles of this invention may also be made from resins produced by the suspension, mass, emulsion or solution processes.
[0077] It is known that some of the materials described above may interact in the final formulation, so that the components of the final formulation may be different from those that are initially added. For instance, metal ions (of, e.g., a detergent) can migrate to other acidic or anionic sites of other molecules. The products formed thereby, including the products formed upon employing the composition of the present invention in its intended use, may not be susceptible of easy description. Nevertheless, all such modifications and reaction products are included within the scope of the present invention; the present invention encompasses the composition prepared by admixing the components described above.
EXAMPLES
[0078] The invention will be further illustrated by the following examples, which sets forth particularly advantageous embodiments. While the examples are provided to illustrate the present invention, they are not intended to limit it.
Example Set 1
[0079] A set of ESD compositions is prepared by mixing a PEG-based TPU with lithium bis(oxalate)borate salt. The salt is added to the TPU via wet absorption. Several samples are prepared at different salt levels and the ESD properties of the compositions are measured. The results of this testing are summarized in the table below.
[0000]
TABLE I
Properties of ESD TPU Compositions
Comp Ex
Example
Example
Example
Example
1-A
1-B
1-C
1-D
1-E
% wt salt
0.0
0.5
1.0
1.5
2.0
in the
composition
Surface
8.5E+09
8.8E+08
5.0E+08
5.3E+08
2.3E+08
Resistivity 1
(ohms/sq)
Volume
4.0E+09
1.8E+08
1.1E+08
1.7E+08
8.0E+07
Resistivity 1
(ohm-cm)
1 Resistivity is measured per ASTM D257 at 50% relative humidity
Example Set 2
[0080] A set of ESD compositions is prepared by mixing a various polymers with lithium bis(oxalate)borate salt. The amount of salt present in each example is 2 percent by weight of the overall composition. The ESD properties of the compositions are measured. The results of this testing are summarized in the table below.
[0000]
TABLE II
Properties of ESD Polymer Compositions
Example
Example
Example
Example
Example
2-A
2-B
2-C
2-D
2-E
% wt salt in the composition
2.0
2.0
2.0
2.0
2.0
Inherently Dissipative
PEBAX ™
PEBAX ™
HYTREL ™
HYTREL ™
PELESTAT ™
Polymer in the composition
MV1074
1657
G3548L
4774
NC6321
Surface Resistivity 1 (ohms/sq)
3.8E+08
1.2E+08
1.4E+09
1.2E+09
2.1E+08
Volume Resistivity 1 (ohm-cm)
8.7E+07
3.9E+07
2.9E+08
8.7E+08
4.8E+07
Static Decay (1000 V-10 V, s)
0.0
0.0
0.0
0.0
0.0
1 Resistivity is measured per ASTM D257 at 50% relative humidity
2 - Static decay is measured per FTMS-101C at 12% relative humidity. The static decay rate measures the time it takes for an article made of the example material to discharge the indicated starting voltage and reach the indicated ending voltage.
Example Set 3
[0081] A set of fully formulated ESD compositions is prepared by mixing a polyethylene glycol (PEG) based thermoplastic polyurethane (TPU) into glycol-modified polyethylene terephthalate (PETG) based formulations and adding an additional additive package. The PEG-based TPU is mixed with a salt, and a different salt is used in each example. Comparative Example 3-A contains lithium (bis)trifluoromethane-sulfonimide, a halogen-containing lithium salt, at a treat rate of about 0.4% by weight. Example 3-B contains lithium bis(oxalate)borate salt, a halogen-free lithium salt, at a treat rate of about 0.3% by weight. The ESD properties of the compositions are measured. The results of this testing are summarized in the table below.
[0000]
TABLE III
Properties of ESD TPU Polymer Compositions
Comp Ex
Example
3-A
3-B
Surface Resistivity 1 (ohms/sq)
5.5E+08
4.6E+08
Volume Resistivity 1 (ohm-cm)
Static Decay (1000 V-10 V, s)
0.1
0.1
1 Resistivity is measured per ASTM D257 at 50% relative humidity
2 - Static decay is measured per FTMS-101C at 12% relative humidity.
Example Set 4
[0082] A set of ESD compositions is prepared by mixing a PEG-based TPU into PETG-based formulations. The PEG-based TPU used in each example is mixed with a salt. Comparative Example 4-A contains lithium (bis)trifluoromethane-sulfonimide, a halogen-containing lithium salt. The Inventive Examples contain lithium bis(oxalate)borate salt, a halogen-free lithium salt. The ESD properties of the compositions are measured. The results of this testing are summarized in the table below.
[0000]
TABLE IV
Properties of ESD Polymer Compositions
Comp Ex
Example
Example
Example
Example
4-A
4-B
4-C
4-D
4-E
Halogen-
NO
YES
YES
YES
YES
Free Salt
% wt salt
3.0
1.0
1.2
1.4
1.6
in the
PEG TPU
Surface
3.2E+09
5.9E+09
5.7E+09
7.0E+09
6.6E+09
Resistivity 1
(ohms/sq)
Volume
1.3E+09
1.3E+09
1.3E+09
1.2E+09
1.2E+09
Resistivity 1
(ohm-cm)
Static Decay
0.2
0.2
0.2
0.2
0.2
(1000
V-10 V, s)
1 Resistivity is measured per ASTM D257 at 50% relative humidity
2 - Static decay is measured per FTMS-101C at 12% relative humidity.
Example Set 5
[0083] A set of fully formulated ESD compositions is prepared by mixing a PEG-based TPU and a PETG-based TPU along with an additional additive package. The PEG-based TPU used in each example is mixed with a salt. Comparative Example 5-A contains lithium (bis)trifluoromethanesulfonimide, a halogen-containing lithium salt, at a treat rate of about 0.05% by weight. The Inventive Example contains lithium bis(oxalate)borate salt, a halogen-free lithium salt, at a treat rate of about 0.04% by weight. The ESD properties of the compositions are measured. The results of this testing are summarized in the table below.
[0000]
TABLE V
Properties of ESD TPU Polymer Compositions
Comp Ex
Example
5-A
5-B
Surface Resistivity 1 (ohms/sq)
3.1E+09
4.4E+09
Volume Resistivity 1 (ohm-cm)
2.5E+09
3.3E+09
Static Decay (1000 V-10 V, s)
7.3
9.0
1 Resistivity is measured per ASTM D257 at 50% relative humidity
2 - Static decay is measured per FTMS-101C at 12% relative humidity.
Example Set 6
[0084] A set of fully formulated ESD compositions is prepared by mixing a PEG-based TPU and an acrylic polymer along with an additional additive package. The PEG-based TPU used in each example is mixed with a salt. Comparative Example 6-A contains lithium (bis)trifluoromethanesulfonimide, a halogen-containing lithium salt, at a treat rate of about 0.09% by weight. The Inventive Example contains lithium bis(oxalate)borate salt, a halogen-free lithium salt, at a treat rate of about 0.07% by weight. The ESD properties of the compositions are measured. The results of this testing are summarized in the table below.
[0000]
TABLE VI
Properties of ESD Acrylic Polymer Compositions
Comp Ex
Example
6-A
6-B
Surface Resistivity 1 (ohms/sq)
2.3E+09
3.1E+09
Volume Resistivity 1 (ohm-cm)
2.4E+09
3.9E+09
Static Decay (1000 V-10 V, s)
5.2
5.7
1 Resistivity is measured per ASTM D257 at 50% relative humidity
2 - Static decay is measured per FTMS-101C at 12% relative humidity.
Example Set 7
[0085] A set of fully formulated ESD compositions is prepared by mixing a PEG-based TPU and a polypropylene-based polymer along with an additional additive package. The PEG-based TPU used in each example is mixed with a salt. Comparative Example 7-A contains lithium (bis)trifluoromethanesulfonimide, a halogen-containing lithium salt, at a treat rate of about 0.4% by weight. The Inventive Example contains lithium bis(oxalate)borate salt, a halogen-free lithium salt, at a treat rate of about 0.3% by weight. The ESD properties of the compositions are measured. The results of this testing are summarized in the table below.
[0000]
TABLE VII
Properties of ESD PP Polymer Compositions
Comp Ex
Example
7-A
7-B
Surface Resistivity 1 (ohms/sq)
4.4E+10
6.5E+10
Volume Resistivity 1 (ohm-cm)
9.0E+10
1.4E+11
Static Decay (1000 V-10 V, s)
3.2
5.2
1 Resistivity is measured per ASTM D257 at 50% relative humidity
2 - Static decay is measured per FTMS-101C at 12% relative humidity.
Example Set 8
[0086] A set of fully formulated ESD compositions is prepared by mixing a PEG-based TPU and a styrenic-based polymer along with an additional additive package. The PEG-based TPU used in each example is mixed with a salt. Comparative Example 8-A contains lithium (bis)trifluoromethanesulfonimide, a halogen-containing lithium salt, at a treat rate of about 0.3% by weight. The Inventive Example contains lithium bis(oxalate)borate salt, a halogen-free lithium salt, at a treat rate of about 0.2% by weight. The ESD properties of the compositions are measured. The results of this testing are summarized in the table below.
[0000]
TABLE VIII
Properties of ESD Styrenic Polymer Compositions
Comp Ex
Example
8-A
8-B
Surface Resistivity 1 (ohms/sq)
3.7E+09
1.1E+10
Volume Resistivity 1 (ohm-cm)
4.3E+09
8.7E+09
Static Decay (1000 V-10 V, s)
0.4
1.0
1 Resistivity is measured per ASTM D257 at 50% relative humidity
2 - Static decay is measured per FTMS-101C at 12% relative humidity.
[0087] The results show that the compositions of the present invention, which utilize a halogen-free lithium containing salt, provide ESD properties comparable to those obtained by the use of halogen-containing salts and similar ESD additives.
[0088] Each of the documents referred to above is incorporated herein by reference. Except in the Examples, or where otherwise explicitly indicated, all numerical quantities in this description specifying amounts of materials, reaction conditions, molecular weights, number of carbon atoms, and the like, are to be understood as modified by the word “about.” Unless otherwise indicated, all percent values, ppm values and parts values are on a weight basis. Unless otherwise indicated, each chemical or composition referred to herein should be interpreted as being a commercial grade material which may contain the isomers, by-products, derivatives, and other such materials which are normally understood to be present in the commercial grade. However, the amount of each chemical component is presented exclusive of any solvent or diluent oil, which may be customarily present in the commercial material, unless otherwise indicated. It is to be understood that the upper and lower amount, range, and ratio limits set forth herein may be independently combined. Similarly, the ranges and amounts for each element of the invention can be used together with ranges or amounts for any of the other elements. As used herein, and unless otherwise defined, the expression “substantially free of” may mean that and amount that does not materially affect the basic and novel characteristics of the composition under consideration, in some embodiments it may also mean no more than 5%, 4%, 2%, 1%, 0.5% or even 0.1% by weight of the material is questions is present, in still other embodiments it may mean that less than 1,000 ppm, 500 ppm or even 100 ppm of the material in question is present. As used herein, the expression “consisting essentially of” permits the inclusion of substances that do not materially affect the basic and novel characteristics of the composition under consideration. | The present invention relates to electrostatic dissipative thermoplatic urethanes (TPU) and compositions thereof. The present invention provides a composition comprising: (a) an inherently dissipative polymer and (b) a halogen-free lithium-containing salt. The invention also provides a shaped polymeric article comprising the inherently dissipative polymer compositions described herein. The invention also provides a process of making the inherently dissipative polymer compositions described herein. The process includes the step of mixing a halogen-free lithium-containing salt into an inherently dissipative polymer. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to an improved sewing machine for sewing overlapping materials and making ornamental seams on a surface of a single material.
As is known, two-yarn sewing machines are conventionally used which substantially comprise a supplying assembly for supplying a first seaming yarn, arranged under the pieces to be seamed, which are mutually overlapped, as well as a further supplying assembly for supplying a second seaming yarn, which is delivered above the pieces to be seamed.
These machines comprise a sewing or seaming needle which is arranged on the top of the seaming region, where are arranged the pieces to be seamed, and which is driven by a reciprocating movement along a movement axis thereof, so as to cause the tip of the needle to traverse the pieces to be seamed, and so as to engage the first yarn to bring it to the top of the pieces to be seamed.
Thus, a yarn loop is formed, which is engaged by a crochet and caused to pass about a spool on which is wound the second seaming yarn.
In conventional sewing machine of the above mentioned type, the thus formed seaming stitch is subjected to a tension, by stretching the first yarn by means of a suitable tensioning element.
At the end of the sewing or seaming operation, the pieces must be disengaged by manually cutting both the top yarn and the bottom yarn.
For each subsequent working cycle, the operator must remove from the crochet a sufficient amount of yarn to hold said yarn during the formation of the first seaming stitches.
During the operation of these machines, because of an exhaustion of the top yarn, it is disadvantageously necessary to replace the spool or reel by means of manual or semi-automatic devices, which, however, greatly reduce the operating speed.
SUMMARY OF THE INVENTION
Accordingly, the aim of the present invention is to overcome the above mentioned drawbacks, by providing a sewing machine allowing to automatically load the yarn directly into the crochet, thereby releasing the operator from the operation of cutting the top yarn, thereby fully exploiting the production capability of the sewing machine.
Within the scope of the above mentioned aim, a main object of the present invention is to provide such a sewing machine releasing the operator from the requirement of manually holding the yarn delivered from the crochet during the formation of the first seaming stitches.
Another object of the present invention is to provide such a sewing machine in which are efficiently eliminated all of the manual operations related to the top yarn and which conventionally must be performed in prior sewing machines.
Yet another object of the present invention is to provide such a sewing machine which is very reliable and safe in operation.
According to one aspect of the present invention, the above mentioned aim and objects, as well as yet other objects, which will become more apparent hereinafter, are achieved by an improved sewing machine, for sewing overlapping materials and making ornamental seams on a single material, comprising:
a first supplying assembly for supplying a first seaming yarn, under pieces to be seamed, a first supplying assembly for supplying a second seaming yarn above said pieces to be seamed, a seaming needle arranged above a seaming region, needle driving means for driving said needle by a reciprocating movement along a movement axis thereof, so as to cause a tip of said needle to pass through said pieces to be seamed and engage said first yarn so as to form a yarn loop traversed by said second yarn as a seaming stitch is formed, characterized in that said sewing machine comprises moreover automatic loading means for automatically loading said second yarn inside a crochet of said second yarn supplying assembly, and cutting means for cutting said second yarn as an operation of said loading means is ended.
BRIEF DESCRIPTION OF THE DRAWINGS
Further characteristics and advantages of the sewing machine according to the present invention will become more apparent hereinafter from the following detailed disclosure of a preferred, though not exclusive, embodiment of said sewing machine, which is illustrated, by way of a merely indicative, but not limitative example, in the figures of the accompanying drawings, where:
FIG. 1a is a schematic front elevation view illustrating the sewing machine according to the present invention in a ready condition for starting a seaming sequence;
FIG. 1b is a further schematic front elevation view illustrating the sewing machine according to the present invention during the sewing or seaming process;
FIG. 1c illustrates the means for automatically loading the second yarn, the sewing machine being shown by a top plan view and as partially cross-sectioned; and
FIGS. 2 to 5 schematically illustrate the sewing machine according to the present invention, by a view like that of FIG. 1c, during the loading of the yarn into the crochet, the cutting of said yarn, after having loaded a sufficient amount of said yarn, and the gripping of the yarn for forming the first seaming stitches.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the number references of the above mentioned figures, the sewing machine according to the present invention, which has been generally indicated by the reference number 1, comprises a bearing element 2, defining a support for the pieces 3 and 4 to be seamed, during the operation of the machine.
Under the bearing element 2 is provided a first yarn supplying assembly, of any known type and not shown for simplicity, for supplying a first seaming or sewing yarn 5, which has been represented by a continuous line, in order to distinguish it from a second seaming or sewing yarn 6, which has been shown by a dashed line, and which is supplied by a second yarn supplying assembly 7, arranged on the top of the pieces 3 and 4 to be seamed.
On the top of the bearing region, defined by said bearing element 2, is provided a seaming needle 9, which has the axis thereof arranged vertically and which can be driven, in a per se known manner, by a reciprocating movement along said axis, in order to cause the needle tip or point to sequentially pass through the region of the pieces 3 and 4 to be seamed, as mutually overlapped, which are arranged at the seaming region, i.e. at the bearing region defined by said bearing element 2, which is provided with a hole at the needle 9 to allow the needle to fully traverse the pieces 3 and 4 to be seamed and engage the first yarn 5 which is supplied at the top end portion of the bearing element 2.
The yarn supplying assembly for supplying the second yarn 6 comprises a crochet holding element 10 which rotatably supports, so as to rotate about a horizontal axis, a crochet 11, including a peak 12 by means of which said crochet, in its rotary movement, can engage the yarn loop formed by the traversing of said tip of said needle 9 through the pieces 3 and 4 to be seamed, and as said needle 9 is caused to raise again.
In the body of the crochet 11 a hollow 13 is formed, in which is engaged the second yarn 6, which is supplied through an opening defined through the frontally facing axial end portion of the crochet 11.
More specifically, the hollow 13 is closed at the front thereof by a small cover 14 which is provided, inside it, at the yarn 6 outlet opening or port, with gripping means for gripping the yarn, said gripping means comprising two tension elements 15 and two loading springs 16, which operate to hold the yarn 6 in a braked condition, as the stitch is formed.
The rotary movement of the crochet 11 is provided by a driving shaft 17 on which is keyed a driving gear 28 which is in turn driven by a driving gear 29, keyed on a shaft 30, in turn synchronously driven with all of the other elements of the sewing machine.
The sewing machine according to the present invention comprises moreover automatic loading means for automatically loading the second yarn 6, in the hollow 13 of the crochet 11, and means for cutting said second yarn 6 on ending the loading operation.
Furthermore, the subject sewing machine is also provided with gripping means 8 for gripping the second yarn 6 exiting the crochet 11 during the formation of the first seaming stitches.
More specifically, the automatic loading means for automatically loading the second yarn 6 comprise a yarn guiding tube 18, which is arranged on a side of the crochet 11 and which can be controllably inserted into a throughgoing hole 60 defined through the crochet holding element 10 and through said crochet 11, transversely of the axis of the latter.
In particular, the yarn guiding tube 18 can be controllably connected to pressurized air supplying means in order to hold said yarn 6 in a straight condition and to subject said yarn to a small pushing force in order to facilitate said yarn 6 in exiting the end of the yarn guiding tube 18 facing the crochet 11.
As shown, the yarn guiding tube 18 is mounted on a supporting element 21, affected by a double-action fluid-dynamic cylinder 22, the operation of which causes the yarn guiding tube 18 to be inserted into or withdrawn from the hollow 13 defined in the crochet 11.
On the supporting element 21 is moreover mounted a loading spring 20 operating on a yarn braking element 19 extending inside the yarn guiding tube 18.
The automatic loading means for automatically loading the second yarn 6 inside the crochet 11 also comprise gripping means for gripping the yarn supplied by the yarn guiding tube 18, which gripping means are arranged on the outlet side of the throughgoing hole 60.
More specifically, these gripping means comprise a fluid-dynamic cylinder 25, of the simple effect type, which is formed inside the crochet holding element 10, and which is connected, by the rod of its piston, extending parallely to the axis of the crochet, to a movable locking element 26 facing a biassing element 27 rigid with the crochet bearing element 10.
Furthermore, the automatic loading means for automatically loading the second yarn 6, inside the crochet 11, also comprise latching means for latching the yarn delivered from the yarn guiding tube 18 inside the hollow 13 formed in the crochet.
Said latching means for latching the yarn supplied by the yarn guiding tube 18 inside the hollow 13 comprise a loading shaft 37, which is arranged coaxially of the crochet 11 and which can be controllably engaged in the hollow 13 of said crochet by causing the loading shaft 37 to be displaced along the axis thereof in order to engage, by the end thereof entering the crochet 11, the yarn supplied by the yarn guiding tube 18 and to bring it outside of the opening controlled by the tensioning elements 15.
About the loading shaft 37, on the portion thereof projecting from the crochet holding element 10, at the opposite portion of the region where is arranged the crochet 11, is provided a toothed pulley 35 which is made rigid in its rotary movement with the loading shaft 37 by a dowel 35, said pulley being suitable to axially slide along said shaft 37.
In particular, said toothed pulley 34 is coupled, by means of a belt 33, to another toothed pulley 32 which is keyed on the output shaft of an auxiliary motor 31, which is controlled by an electronic driving element, for example a microprocessor which, as instructed by the operator, by rotatively operating the loading shaft 37 about the axis thereof, will cause a sufficient amount of yarn to be wound inside said hollow 13, so as to fit the seam to be performed.
More specifically, the loading shaft 37 can be engaged, by the tip thereof, which is so arranged as to engage the yarn supplied by the yarn guiding tube 18, into the hollow 13 of the crochet, by means of a fluid-dynamic cylinder 38 which, by the piston rod thereof, is connected to a connection plate 39 to the loading shaft 37.
The cutting means for cutting the yarn delivered by the yarn guiding tube 18 comprise a guillotine type of blade 24 which is arranged on a side of the crochet 11, i.e. on the portion thereof opposite to the movable locking element 26, and which is connected to the piston rod of the piston of a fluid-dynamic cylinder, of the simple effect type, 23, also formed in the crochet holder element 10 and having the axis thereof parallel to the axis of said crochet.
The supply assembly 7 comprises moreover a fixed guiding element 40 which will operate, owing to the specifically designed contour thereof, to properly orient about the axis thereof the loading shaft 37 on which is keyed a movable guiding element 41 which, as it engages with the fixed element 40, will cause the loading shaft to be returned to its ideal starting condition.
The gripping means 8 provided for supporting and holding the seaming yarn 6 as the first stitches are formed, comprise a fluid-dynamic cylinder 42 which, by the piston rod of the piston thereof, is coupled to a gripper holding movable element 43, supporting a top arm of the gripper 44 and a bottom arm of the gripper 45. The opening and closing movements of the two arms of the gripper are driven by a gripper closing piston 46.
The sewing machine according to the present invention operates as follows.
For performing seaming stitches it is necessary, as a first operation, to load into the hollow 13 of the crochet 11, the required amount of yarn 6.
This operation is performed by the sewing machine operator by means of an electronic driving or control element, based on the seaming requirements or automatically if said electronic control element has been preliminarily programmed.
In this case, the loading operation is performed in an automatic manner at the end of each seaming cycle.
More specifically, this operation is performed, as shown in FIG. 2, according to a movement sequence which are automatically quickly carried out as follows.
Pressurized air is supplied through the duct A of the fluid-dynamic cylinder 22 so as to cause the support element 21 on which is arranged the yarn guiding tube 18 to be displaced, to traverse the crochet holder element 10, the crochet 11 and the driving shaft 17, by passing through the hole 60.
Simultaneously, pressurized air is supplied through the duct L of the yarn guiding tube 18, which operates to support the yarn and displace it by several millimeters so as to cause, by supplying pressurized air into the duct C, the piston of the cylinder 25 to be driven, on the rod of said piston being connected the movable locking element 26, which will lock the yarn 6 against the abutment element 27 fixedly arranged on the crochet holding element 10.
Then, the pressurized air flow to the duct L is stopped and, successively, as shown in FIG. 3, pressurized air is released from the duct A and introduced into the duct B so as to cause the supporting element 21, and accordingly the yarn guiding tube 18, to be withdrawn.
The yarn braking element 19, in cooperation with the loading spring 20, will operate, in this step, in order to restrain the yarn 6 to prevent the latter from sliding off the yarn guiding tube 18 and so as to held said yarn stretched during the engaging of the loading shaft 37 in the inside of the hollow 13.
At this point, pressurized air is supplied into the duct E of the fluid-dynamic cylinder B which, through the connection plate 39, will drive the loading shaft 37 to engage by the tip thereof the yarn 6 and so as to be sandwiched between the two tensioning elements 15 to cause the loading springs 14 to be compressed.
Then, the motor 31 will start to rotate, by consequently driving the toothed pulley 32, the toothed belt 33, toothed pulley 34 which, through the dowel 35 will cause the loading shaft 37 to turn so as to wind on itself a programmed amount of the yarn 6, under the control of the control electronic element.
Near the full loading of the yarn 6, during the rotary movement of the loading shaft 37, as is shown in FIG. 4, pressurized air is supplied to the duct D, so as to cause the cylinder 23 piston, on the piston rod of which is engaged the blade 24, to advance so as to cut the yarn 6.
The rotary movement of the loading shaft 37 will continue up to cause the yarn 6 to be fully wound up.
Then, pressurized air is released from the duct C so as to cause the springs of the cylinder 25 to withdraw the piston the piston rod of which is connected to the movable locking element 26, pressurized air being moreover released from the duct D so that the spring of the cylinder 23 will withdraw the cylinder piston on the piston rod of which is coupled the cutting blade 24.
At the end of the loading operation, pressurized air will be released from the duct E of the fluid dynamic cylinder 38, while pressurized air will be supplied to the duct F to cause the piston, on the piston rod of which is connected the coupling plate 39 to withdraw so as to also withdraw the loading element 37, to release or disengage the tensioning elements 15.
The latter will hold, by the loading springs 14, the yarn 6 from the crochet 11 thereby subjecting said yarn to a proper seaming tension.
As the loading shaft 37 is withdrawn, the programmed amount of yarn 6 will be left inside the hollow 13 of the crochet 11.
During its withdrawing movement, the movable guide element 41 keyed on the loading shaft 37 will engage with the fixed guide element 40 which will cause the loading shaft 37 to be returned to its ideal starting conditions.
At this time, and as is shown in FIG. 5, pressurized air is again supplied to the duct G of the cylinder 42, on the piston rod of which is affixed the gripper bearing movable element 43, inside of which slides the gripper closing piston 46.
As the gripper closing piston 46 is caused to advance, the two arms 44 and 45 of the gripper will be closed about the yarn 6 exiting the crochet 11.
Thus, the sewing machine will be ready again to start its seaming cycle, without any interventions by the operator.
In this connection it should be apparent that the gears 28 and 29 and shaft 30 will operate to connect the driving shaft 17 and, accordingly, the crochet 11, to a plurality of elements which are kinematically synchronously connected, in a per se known manner, thereby driving said elements so as to properly form the seaming stitches.
After having made some seaming stitches, the gripping means 8 will be disenergized, by releasing pressurized air from the duct G and supplying pressurized air to the duct H thereby causing the gripper holder movable element 43 of the gripper closing piston 46 to withdraw, with a consequent opening of the arms 44 and 45 of the gripper.
At the end of the seaming operation, the operator should recover the small amount of yarn 6 held in the cavity 13 by the crochet 11 by pulling the seamed pieces 3 and 4 without the need of cutting the yarn 6.
Then, the operator will deposit the seamed pieces 3 and 4, and will provide other pieces to be seamed, and, in the meanwhile, the electronic control device will cause the yarn 6 loading cycle to be quickly repeated, so as to load again the yarn 6 into the cavity 13 of the crochet 11, thereby eliminating any dead loading delays as well as cutting delays and with a consequent great saving of yarn 6 which, in conventional sewing machine is on the contrary randomly taken by the operator for forming the first seaming stitches.
Thus, the operator must not take care of the top yarn 6, thereby eliminating any manual operations.
From the above disclosure and from the observations of the figures of the accompanying drawings, it should be apparent that the invention fully achieves the intended aim and objects.
In particular, the fact is to be pointed out that a two-yarn sewing machine has been provided which is specifically designed for automatically loading, cutting, locking and precisely controlling the amount of the top yarn necessary for the seaming operation, without requiring any manual operations, thereby providing a high production yield.
The thus disclosed sewing machine is susceptible to several variations and modifications all of which will come within the scope of the inventive idea.
Moreover, all of the details can be replaced by other technically equivalent elements.
In practicing the invention, the used materials, as well as the contingent size and shapes, can be any, according to requirements. | An improved sewing machine, for sewing overlapping materials and making ornamental seams on a single material comprises: a first supplying assembly for supplying a first seaming yarn, arranged under the pieces to be seamed, a second supplying assembly for supplying a second seaming yarn, arranged above the pieces to be seamed, a needle arranged on the top of the seaming region and a needle driving device for driving the needle by a reciprocating movement along a movement axis thereof in order to cause the needle tip to pass through the pieces to be seamed and to engage the first yarn so as to provide a yarn loop traversed by the second yarn, as a seaming stitch is formed. The machine has the main feature that it further comprises a loading device for automatically loading the second yarn, inside a "crochet" of the assembly supplying the second yarn, as well as a cutting device for cutting the second yarn at the end of the second yarn loading operation. | 3 |
This invention relates to earth-moving vehicles that include precision foundation trenchers which remove all likely consistencies of earth, ranging from hard and rocky earth to loose dirt, and which pile the earth in ridges spaced stably apart from foundation trenches without manual labor.
Foundation trenches are widely known and used. None, however, are known to be capable of blade-clearing trench areas, removing all likely consistencies of soil, ranging from hard and rocky earth to loose dirt, and placing the earth stably apart from foundation trenches without manual labor in a manner taught by this invention.
Prior art found to be related but different includes the following:
U.S. Pat. No.
Inventor
Date
3,982,688
Taylor
Sep. 28, 1976
4,050,171
Teach
Sep. 27, 1977
4,095,358
Courson et al.
Jun. 20, 1978
4,255,883
Ealy
Mar. 17, 1981
4,908,967
Leece
Mar. 20, 1990
4,936,678
Gordon et al
Jun. 26, 1990
Re. 34,620
Camilleri
May 31, 1994
5,559,725
Nielson et al.
Sep. 24, 1996
5,639,182
Paris
Jun. 17, 1997
2002/0056211 A1
Kelly et al.
May 16, 2002
6,736,216 B2
Savard et al.
May 18, 2004
SUMMARY OF THE INVENTION
Objects of patentable novelty and utility taught by this invention are to provide an all-earth foundation trencher which:
can blade-clear foundation-trench area ahead of it without manual labor for supporting earth-mover track and for containing ridges of moved earth that are spaced stably apart from a foundation trench dug with an aft portion of the all-earth foundation trencher;
can maintain precise verticality of a mechanized digger and resulting required preciseness of verticality of trench walls on variably horizontal, sloped and uneven foundation-trench areas;
has endless-track mobility for rigid vehicle support of the mechanized digger;
can dig all likely consistencies of soil, ranging from hard and rocky earth to loose dirt;
can place the earth stably apart from foundation trenches; and
can dig predeterminedly variable trench widths and depths.
This invention accomplishes these and other objectives with an all-earth foundation trencher having a digger body pivotal selectively on a track chassis. The digger body has an earth-mover blade that is manipulatable multi-directionally on a front end. A digger boom has a base end that is pivotal vertically on a boom base that is predeterminedly forward from an aft end of the digger body. The digger boom has a digger end extended rearward from the digger body. A digger head is manipulatable on the digger end of the digger boom for power-digging foundation trenches having desired widths and depths in all likely consistencies of soil, ranging from hard and rocky earth to loose dirt. Conveyors are positioned intermediate the track chassis and the digger head for conveying removed earth sufficiently far from either or both sides of a foundation trench that the removed earth will not spill back into the foundation trench. Form blades can be positioned proximate opposite sides of the digger head for forming walls on trench sides of berms to further assure that removed earth will not spill back into the foundation trenches. A compaction roller can be positioned aft of the digger head where it can be articulated to bear sufficient weight of the all-earth foundation trencher for a reliable concrete base. A laser guide proximate the digger head provides accurate directional and attitudinal digging with the digger head.
BRIEF DESCRIPTION OF DRAWINGS
This invention is described by appended claims in relation to description of a preferred embodiment with reference to the following drawings which are explained briefly as follows:
FIG. 1 is a side elevation view of the all-earth foundation trencher with a digger head in a raised mode;
FIG. 2 is a partially cutaway top view;
FIG. 3 is a front view;
FIG. 4 is a partially cutaway rear view with the digger head in a lowered digging mode;
FIG. 5 is a fragmentary side view of a front corner showing an earth-mover blade in down mode with solid lines and in an up mode with dashed lines;
FIG. 6 is a fragmentary side view of the front corner showing the earth-mover blade in down mode with solid lines and slanted in forward and aft modes with dashed lines;
FIG. 7 is a fragmentary top view of a front portion of a track-laying chassis and tracks showing the earth-mover blade in an orthogonal mode in relationship to the tracks with solid lines and beveled laterally with dashed lines;
FIG. 8 is a fragmentary front view of a front portion of a track-laying chassis and tracks showing the earth-mover blade in an orthogonal mode in relationship to the tracks with solid lines and beveled vertically with dashed lines;
FIG. 9 is a top view of a ball-and-socket controller of orientation and modes of the earth-mover blade;
FIG. 10 is a top view of a boom-controller knob for raising and lowering a digger boom;
FIG. 11 is a top view of a dig-width knob for controlling digger-head width;
FIG. 12 is a top view of a head-slant knob for controlling digger-head slant;
FIG. 13 is a top view of a dig-speed knob for controlling digger-head speed;
FIG. 14 is a top view of a verticality-control knob;
FIG. 15 is a partially cutaway fragmentary front view of a rock-digger variable-width digger chain;
FIG. 16 is a side view of the FIG. 15 illustration;
FIG. 17 is a top view of a backboard-width knob for controlling backboard width;
FIG. 18 is a top view of a compaction-controller knob for controlling compaction pressure;
FIG. 19 is a top view of a first-conveyor controller knob for controlling reach of a first-side conveyor;
FIG. 20 is a top view of a second-conveyor controller knob for controlling reach of a second-side conveyor;
FIG. 21 is a top view of a conveyor-direction controller knob for controlling conveyance direction;
FIG. 22 is a top view of a safety-controller knob for positioning safety panels;
FIG. 23 is a top view of a pile-controller knob for firming up ridges of piled earth at sides of trenches;
FIG. 24 is a top view of a mobility-controller knob for directional control of chassis travel;
FIG. 25 is a top view of an accuracy-controller knob for override of automated laser control of verticality of trench walls;
FIG. 26 is a fragmentary side view of representative operational controllers with a control knob in relationship to a knob plate on the control panel with control communication through a control communicator;
FIG. 27 is a partially cutaway rear view of the all-earth foundation trencher showing two-side conveyance of earth with the digger head in a lowered digging mode; and
FIG. 28 is a schematic of controls in relationship to the control panel.
DESCRIPTION OF PREFERRED EMBODIMENT
A description of the preferred embodiment of this invention follows a list of numbered terms which designate its features with the same numbers on the drawings and in parentheses throughout the description and throughout the patent claims.
1.
Digger body
2.
Blade end
3.
Digger end
4.
First side
5.
Second side
6.
Chassis-attachment base
7.
Track-laying chassis
8.
First track
9.
Second track
10.
Prime mover
11.
Control-power source
12.
Chassis connection
13.
Control-power distributor
16.
Earth-mover blade
17.
Blade-control beams
19.
Digger boom
20.
Boom-control rod
22.
Digger head
23.
Head-control rod
25.
Compact roller
26.
Compaction-control rod
27.
Compaction controller
28.
Earth conveyor
29.
First-side conveyor
30.
Second-side conveyor
31.
Central conveyor
32.
First-conveyor control rod
33.
First-conveyor controller
34.
Second-conveyor control rod
35.
Second-conveyor controller
36.
Conveyance-direction
controller
37.
Safety panels
38.
Safety control rods
39.
Safety controller
40.
Pile blades
41.
Pile-control rods
42.
Pile controller
43.
Pilot house
44.
Operator seat
45.
Control panel
46.
Directional indicator
47.
Body-direction point
48.
Chassis-direction point
49.
Knob plate
50.
Verticality indicator
51.
Body-verticality point
52.
Chassis-verticality point
53.
Ball-and-socket controller
54.
Ball
55.
Socket
56.
Blade plate
57.
Epicentral knob
58.
Boom-controller knob
59.
Depth point
60.
Up mark
61.
Down mark
62.
Boom plate
63.
Incremental marks
64.
Dig-width knob
65.
Head-slant knob
66.
Dig-speed knob
67.
Width point
68.
Min-width mark
69.
Max-width mark
70.
Width-indicator plate
71.
Slant point
72.
No-slant mark
73.
Max-slant mark
74.
Slant-indicator plate
75.
Speed point
76.
Stop mark
77.
Max-speed mark
78.
Speed-indicator plate
79.
Digger backboard
80.
Cutter chain
81.
Central digger chain
82.
Left digger chain
83.
Right digger chain
84.
Chain-sprocket teeth
85.
Top-central chain wheel
86.
Bottom-central chain wheel
87.
Top-left chain wheel
88.
Bottom-left chain wheel
89.
Top-right chain wheel
90.
Bottom-right chain wheel
91.
Top sprocket axle
92.
Bottom sprocket axle
93.
Sprocket-wheel slider
94.
Backboard first side
95.
Backboard second side
98.
Backboard-width controller
99.
Laser guide
100.
Accuracy controller
101.
Control communicator
102.
Operational controllers
104.
Control knob
105.
Rock-digger blades
106.
Directional reference point
Referring to FIGS. 1–8 , the all-earth foundation trencher has a digger body ( 1 ) with a blade end ( 2 ), a digger end ( 3 ), a first side ( 4 ), a second side ( 5 ) and a chassis-attachment base ( 6 ) on a track-laying chassis ( 7 ). The track-laying chassis ( 7 ) has a first track ( 8 ) and a second track ( 9 ). A prime mover ( 10 ) is positioned preferably on proximate the blade-end of the digger body ( 1 ).
The prime mover ( 10 ) has power-transfer communication with a control-power source ( 11 ) on the digger body ( 1 ) for providing power for operating components of the all-earth foundation trencher. Preferably for most operational components, the power provided by the control-power source ( 11 ) is hydraulic fluid pressure. This is basically a hydraulic-power system. However, some components and some portions of components are articulated to require some electrical, others some pneumatic power and others mechanical power. All are provided by the control-power source ( 11 ).
A chassis connection ( 12 ) is in predetermined communication intermediate the chassis-attachment base ( 6 ) on the digger body ( 1 ) and the track-laying chassis ( 7 ). In addition to providing standard mechanical and hydraulic linkage predeterminedly from the prime mover ( 10 ) to the first track ( 8 ), to the second track ( 9 ) and to other operational components on the track-laying chassis ( 7 ), the chassis connection ( 12 ) also provides novel verticality pivot of the digger body ( 1 ) on a pivot axis that is collinear to linear axes of the track-laying chassis ( 7 ), the first track ( 8 ) and the second track ( 9 ). This allows control of verticality of a digger head ( 22 ) that is orthogonal to the digger body ( 1 ).
The control-power source ( 11 ) has control-power communication with a control-power distributor ( 13 ) that is positioned on the digger body ( 1 ).
The chassis connection ( 12 ) includes track-directional communication of control of mobility of the first track ( 8 ) and the second tract ( 9 ) with a mobility controller in communication with the control-power distributor ( 13 ). The chassis connection ( 12 ) includes body-orientational control of orientation that includes at least verticality of the digger body ( 1 ) in relationship to orientation of the track-laying chassis ( 7 ) with an orientation controller in communication with the control-power distributor ( 13 ).
An earth-mover blade ( 16 ) is manipulatable on blade-control beams ( 17 ) projected from a blade-attachment portion of the track-laying chassis ( 7 ). The earth-mover blade ( 16 ) has a predetermined plurality of directional orientations controlled by a blade controller in communication with the control-power distributor ( 13 ).
A digger boom ( 19 ) is pivotal vertically from a boom-attachment portion of the digger body ( 1 ). The digger boom ( 19 ) is manipulated vertically with at least one boom-control rod ( 20 ) having a boom controller in communication with the control-power distributor ( 13 ).
A digger head ( 22 ) is pivotal vertically on a digger-attachment portion of the digger boom ( 19 ). The digger head ( 22 ) is manipulated vertically with at least one head-control rod ( 23 ). The digger head ( 22 ) has a head controller in communication with the control-power distributor ( 13 ).
A digger backboard ( 79 ) is positioned aft of a cutter chain ( 80 ) of the digger head ( 22 ) for deterring loose earth from falling from the cutter chain ( 80 ).
A compact roller ( 25 ) is positioned proximate a bottom-aft portion of the digger head ( 22 ) with the compact roller ( 25 ) being manipulated vertically on the digger head ( 22 ) with at least one compaction-control rod ( 26 ) having a compaction controller ( 27 ) in communication with the control-power distributor ( 13 ).
An earth conveyor ( 28 ) is positioned predeterminedly intermediate the digger head ( 22 ) and a conveyor-attachment portion of the track-laying chassis ( 7 ). The earth conveyor ( 28 ) includes a first-side conveyor ( 29 ), a second-side conveyor ( 30 ) and at least one central conveyor ( 31 ). The first-side conveyor ( 29 ) is manipulated horizontally with at least one first-conveyor control rod ( 32 ) having a first-conveyor controller ( 33 ) in communication with the control-power distributor ( 13 ). The second-side conveyor ( 30 ) is manipulated horizontally with at least one second-conveyor control rod ( 34 ) having a second-conveyor controller ( 35 ) in communication with the control-power distributor ( 13 ). The central conveyor ( 31 ) is articulated for conveying earth to the first-side conveyor ( 29 ) and to the second-side conveyor ( 30 ) selectively with a conveyance-direction controller ( 36 ) in communication with the control-power distributor ( 13 ).
Safety panels ( 37 ) are manipulated vertically and laterally proximate opposite sides of the digger head ( 22 ) with safety control rods ( 38 ) having a safety controller ( 39 ) in communication with the control-power distributor ( 13 ).
Pile blades ( 40 ) are manipulated vertically and horizontally proximate opposite sides of the digger head ( 22 ) with pile-control rods ( 41 ) having a pile controller ( 42 ) in communication with the control-power distributor ( 13 ).
A pilot house ( 43 ) is positioned and articulated on the digger body ( 1 ) for forward visibility of earth-mover-blade factors and rearward for visibility of earth-digger factors from an operator seat ( 44 ) in control-operable proximity to a control panel ( 45 ) in operable relationship to the control-power distributor ( 13 ).
The chassis connection ( 12 ) can include predetermined universality. The universality can include directional rotation of the digger body ( 1 ) in relationship to linear direction of the first track ( 8 ) and the second track ( 9 ) of the track-laying chassis ( 7 ). The universality can include verticality pivot of the digger body ( 1 ) in relationship to horizontality of the first track ( 8 ) and the second track ( 9 ) of the track-laying chassis ( 7 ).
Referring to FIGS. 24 and 28 , the mobility controller can include a directional indicator ( 46 ) having a body-direction point ( 47 ) for selective steering-control alignment of the digger body ( 1 ) and the track-laying chassis ( 7 ) by aligning the body-direction point ( 47 ) with a chassis-direction point ( 48 ) on a knob plate ( 49 ).
Referring to FIGS. 14 and 28 , a verticality controller can include a verticality indicator ( 50 ) having a body-verticality point ( 51 ) and a chassis-verticality point ( 52 ) on the knob plate ( 49 ) for selectively aligning verticality of the digger body ( 1 ) with verticality of the track-laying chassis ( 7 ) by aligning the body-verticality point ( 51 ) with the chassis-verticality point ( 52 ).
The directional indicator ( 46 ) and the verticality indicator ( 50 ) are preferably articulated with a low profile and positioned on the control panel ( 45 ) for ease of access and visibility and for avoidance of unintended actuation.
The directional indicator ( 46 ) preferably includes precise measurement, readout and fixedly automatic control of steering-control alignment for precise directional control of trench digging.
The verticality indicator ( 50 ) preferably includes laser-precision measurement, readout and fixedly automatic control of body verticality for precise verticality control of trench digging with the digger head ( 22 ).
Referring to FIGS. 5–9 and 28 , for plural-way controllability of blade orientation on the blade control beams ( 17 ), the blade controller can include a ball-and-socket controller ( 53 ) having a ball ( 54 ) that is rotational universally in socket ( 55 ) in a blade plate ( 56 ) with the ball-and-socket controller ( 53 ) being articulated for controlling orientation of the earth-mover blade ( 16 ). The ball ( 54 ) has an epicentral knob ( 57 ) that is rotational clockwise from a directional-reference point ( 106 ) on the blade plate ( 56 ) for clockwise steering of the earth-mover blade ( 16 ) clockwise from orthogonality to a linear axis of the track-laying chassis ( 7 ). The epicentral knob ( 57 ) is rotational counterclockwise from the directional-reference point ( 106 ) on the blade plate ( 56 ) for steering the earth-mover blade ( 16 ) counterclockwise from orthogonality to the linear axis of the track-laying chassis ( 7 ). The epicentral knob ( 57 ) is pivotal downward for orienting the earth-mover blade ( 16 ) clockwise from horizontality and is pivotal upward for orienting the earth-mover blade ( 16 ) counterclockwise from horizontality. The epicentral knob ( 57 ) is pivotal horizontally forward for orienting the earth-mover blade ( 16 ) clockwise from verticality and is pivotal vertically rearward for orienting the earth-mover blade ( 16 ) counterclockwise from verticality.
The ball-and-socket controller ( 53 ) is articulated with a low profile and positioned on the control panel ( 45 ) for ease of access and visibility and for avoidance of unintended actuation.
The ball-and-socket controller ( 53 ) preferably includes precise measurement, readout and fixedly automatic control of orientation of the earth-mover blade ( 16 ) for desirably precise mechanized clearing, grading and leveling of foundation-trench areas, for accurate track mobility and for reliable piling of removed earth beside foundation trenches.
Referring to FIGS. 10 and 28 , the boom controller can includes a boom-controller knob ( 58 ) that is articulated for controlling the digger boom ( 19 ) with a depth point ( 59 ) that is rotational clockwise selectively intermediate an up mark ( 60 ) and a down mark ( 61 ) on a boom plate ( 62 ) on the control panel ( 45 ) for lowering the digger boom ( 19 ). The depth point ( 59 ) is rotational counterclockwise selectively intermediate the down mark ( 61 ) and the up mark ( 60 ) for raising the digger boom ( 19 ).
The boom-controller knob ( 58 ) is articulated preferably with a low profile and positioned on the control panel ( 45 ) for ease of access and visibility and for avoidance of unintended actuation.
The boom controller preferably includes selectively precise measurement, readout and fixedly automatic control of digging depth of the digger head ( 22 ) by rotation of the boom-controller knob ( 58 ).
Measurement of digging depth can include incremental marks ( 63 ) on the boom plate ( 62 ) intermediate the up mark ( 60 ) and the down mark ( 61 ).
Referring to FIGS. 11–13 and 28 , the head controller can include a dig-width knob ( 64 ) articulated for controlling dig width of the digger head ( 22 ), a head-slant knob ( 65 ) articulated for controlling slant of the digger head ( 22 ) and dig-speed knob ( 66 ) articulated for controlling dig speed of the digger head ( 22 ).
The dig-width knob ( 64 ) has a width point ( 67 ) that is rotational selectively intermediate a min-width mark ( 68 ) and a max-width mark ( 69 ) on a width-indicator plate ( 70 ) for width control.
The head-slant knob ( 65 ) has a slant point ( 71 ) that is rotational selectively intermediate a no-slant mark ( 72 ) and a max-slant mark ( 73 ) on a slant-indicator plate ( 74 ) for slant control.
The dig-speed knob ( 66 ) has a speed point ( 75 ) that is rotational selectively intermediate a stop mark ( 76 ) and a max-speed mark ( 77 ) on a speed-indicator plate 20 ( 78 ) for dig-speed control.
The dig-width knob ( 64 ), the head-slant knob ( 65 ) and the dig-speed knob ( 66 ) can include a group of three separate knobs on the control panel ( 45 ).
Referring to FIGS. 15–16 , the digger head ( 22 ) preferably includes a central digger chain ( 81 ), a left digger chain ( 82 ) and a right digger chain ( 83 ). The central 25 digger chain ( 81 ) is positioned on chain-sprocket teeth ( 84 ) of a top-central chain wheel ( 85 ) and on bottom-central chain wheel ( 86 ). The left digger chain ( 82 ) is positioned on chain-sprocket teeth ( 84 ) of a top-left chain wheel ( 87 ) and on chain-sprocket teeth ( 84 ) of a bottom-left chain wheel ( 88 ). The right digger chain ( 83 ) is positioned on chain-sprocket teeth ( 84 ) of a top-right chain wheel ( 89 ) and on chain-sprocket teeth ( 84 ) of a bottom-right chain wheel ( 90 ). The top-central chain wheel ( 85 ) is affixed to a central portion of a top sprocket axle ( 91 ) and the bottom-central chain wheel ( 86 ) affixed to a central portion of a bottom sprocket axle ( 92 ).
The top-left chain wheel ( 87 ) and the top-right chain wheel ( 89 ) are in linearly sliding contact with the top sprocket axle ( 91 ). The bottom-left chain wheel ( 88 ) and the bottom-right chain wheel ( 90 ) are in linearly sliding contact with the bottom sprocket axle ( 92 ).
The head controller includes a sprocket-wheel slider ( 93 ) that is operable by the dig-width knob ( 64 ) for controlling dig width of the digger head ( 22 ).
Referring to FIGS. 1–4 , the digger backboard ( 79 ) includes a backboard first side ( 94 ) positioned proximate a first side of the digger head ( 22 ) and a backboard second side ( 95 ) positioned proximate a second side of the digger head ( 22 ). The backboard first side ( 94 ) and the backboard second side ( 95 ) have portions that are overlapped selectively for desired combined width thereof. Combined width of the backboard first side ( 94 ) and the backboard second side ( 95 ) is manipulated by a backboard-width controller ( 98 ) in communication with the control-power distributor ( 13 ).
The backboard-width controller ( 98 ) is articulated with a low profile that includes a knob positioned on the control panel ( 45 ) for ease of access and visibility and for avoidance of unintended actuation.
Referring to FIGS. 18 and 28 , the compaction controller ( 27 ) is articulated with a low profile that includes a knob positioned on the control panel ( 45 ) for ease of access and visibility and for avoidance of unintended actuation.
Referring to FIGS. 19–21 and 28 , the first-conveyor controller ( 33 ), the second-conveyor controller ( 35 ) and the conveyance-direction controller ( 36 ) are articulated with low profile that includes at least one knob positioned on the control panel ( 45 ) for ease of access and visibility and for avoidance of unintended actuation.
Referring to FIGS. 22 and 28 , the safety controller ( 39 ) is articulated with low profile that includes at least one knob positioned on the control panel ( 45 ) for ease of access and visibility and for avoidance of unintended actuation.
Referring to FIGS. 23 and 28 , the pile controller ( 42 ) is articulated with low profile that includes at least one knob positioned on the control panel ( 45 ) for ease of access and visibility and for avoidance of unintended actuation.
Referring to FIGS. 1 , 25 and 28 , at least one laser guide ( 99 ) is articulated and positioned proximate the digger head ( 22 ) for control-assurance feedback of verticality accuracy of trench digging to an accuracy controller ( 100 ) on the control panel ( 45 ).
Referring to FIGS. 2 and 28 , the control-power source ( 11 ) includes hydraulic power in communication from the control-power distributor ( 13 ) to operational controllers ( 102 ) of operational components of the all-earth foundation trencher. The operational controllers ( 102 ) include control communication of hydraulic actuators of the operational components. Control-power communication of the operational controllers ( 102 ) with the control-power distributor ( 13 ) includes communication through a predetermined control communicator ( 101 ) which can include hydraulic, mechanical and electrical components.
Referring to FIGS. 26 and 28 , the operational controllers ( 102 ) can include control knobs ( 104 ) on knob plates ( 49 ) positioned on the control panel ( 45 ). The operational controllers ( 102 ) are articulated for controlling the hydraulic actuators through the control communicator ( 101 ) by selective communication with the control knobs ( 104 ).
A new and useful all-earth foundation trencher having been described, all such foreseeable modifications, adaptations, substitutions of equivalents, mathematical possibilities of combinations of parts, pluralities of parts, applications and forms thereof as described by the following claims and not precluded by prior art are included in this invention. | An all-earth foundation trencher has a digger body ( 1 ) pivotal selectively on a track-laying chassis ( 7 ). The digger body has an earth-mover blade ( 16 ) that is manipulatable multi-directionally on a front end. A digger boom ( 19 ) has a base end that is pivotal vertically forward from an aft end of the digger body. A digger head ( 22 ) is manipulatable on a digger end of the digger boom for power-digging foundation trenches having desired widths and depths in all likely consistencies of earth that ranges from hard and rocky earth to loose dirt. Conveyors ( 28–31 ) are positioned intermediate the track-laying chassis and the digger head for conveying removed earth sufficiently far from either or both sides of a foundation trench that the removed earth will not spill back into the foundation trench. A laser guide ( 99 ) proximate the digger head provides control assurance of accurate attitudinal digging. Operational controllers ( 102 ) include control knobs ( 104 ) on knob plates ( 49 ) positioned on a control panel ( 45 ). The operational controllers are articulated for controlling hydraulic actuators through a control communicator ( 101 ) by selective communication with the control knobs for low-profile, convenient and non-fatiguing ergonomic control of operations. | 4 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to the field of cottonseed processing and more particularly to delinting cottonseed after it has been ginned and before the seed is itself processed to recover oil and other useful byproducts. In greater particularity the present invention relates to improvements in both the efficiency of the delinter and ease of maintenance of the delinter by the operators.
[0002] The present invention is an improvement over the delinting apparatus disclosed in U.S. Pat. No. 4,967,448 which is the closest prior art. The '448 patent discloses the basic delinting process and components used in a delinter and its disclosure is incorporated herein by reference in its entirety. As noted in the '448 patent, unprocessed cotton brought from the field to a cotton gin for ginning will produce bales of long cotton fibers while the remaining cottonseed will have a residue of lint thereon. Cottonseed processing apparatus has long been used to remove residue lint from cottonseeds which have already been processed in conventional cotton gins to remove the long, staple fibers from the seeds. The lint removed from the cottonseed is one of the salable products procured from the cotton operation.
[0003] Lint is removed in a single pass, called mill run cut lint, or multiple passes through a cottonseed processing apparatus known as a delinter. In multiple pass processes, the first pass lint yields high quality cellulose, used in manufacturing high quality paper. Lint from the second and third passes or mill run cut lint is usually sold in blended form, with munitions lint, hygienic cottonballs and various cellulose based chemicals being common end uses.
[0004] It is also desirable to delint seeds to enhance processability for oil extraction. In oil extraction apparatus, lint is a contaminant which detracts from the overall quality of the oil and adds to the maintenance requirements for the oil extraction apparatus.
[0005] In the conventional delinter, the lint is continuously removed from seed by subjecting a rotating mass of seed or “seed roll” to a rotating, ganged cylinder of toothed saw blades passing between ribs in a “grate”. The lint is “doffed” from the saw teeth by a revolving brush cylinder.
[0006] The seed roll is rotated in a “float chamber” where the seed roll is subjected to the saws. Rotation of the seed roll is caused by a rotating paddle wheel “float” in the center of the seed roll. The density of the seed roll in the float chamber is controlled by a feedback controlled paddle wheel roll feeder upstream of the float. The rotating speed of the roll feeder is determined by the amperage required by the saw cylinder motor, such that seed roll density is maintained at an optimum level for efficient delinting. Typically, however the width of the feeder has been narrower than the width of the saw cylinder, and cottonseed was required to migrate to the ends of the cylinder in an attempt to process the seed through the saw. Rather than flowing smoothly this lateral migration created flow problems as the cottonseed tended to accumulate at the ends of the saw cylinder, resulting in split seeds with a consequent release of oil onto the lint and increased hull content in the lint discharged at both ends of the saw cylinder. Thus, recent delinters such as shown in the '448 patent, which were more energy efficient suffered from decreased quality of lint when operated at energy saving rates.
[0007] Machines used for delinting cottonseed are not to be confused with cotton gins which remove the staple fiber from the seed. Delinting apparatus use the seed cotton which has already been ginned and must be further processed to remove the residual lint from the seed. These machines operate year round rather than seasonally when the cotton is harvested and ginned. In use, the saw cylinders wear rapidly and require frequent sharpening, so a convenient means of accessing and removing the saw cylinder is required. Although the '448 patent greatly improved the access of the operator to the saw cylinder, machines built since that disclosure have suffered from significant drawbacks in operator ease of maintenance. Specifically, the prior machines have required multiple steps to remove the saw cylinder for sharpening, an event that occurs as frequently as daily over the operational life of the machine. For example, each time the saw was removed, the operator had to first loosen the tension on the drive belts from the saw motor and the float motor, then remove the belts, which required that he reach across the ends of the spindle of the saw cylinder and float cylinder and across the discharge augers, then open the gratefall with a fluid actuated cylinder sufficiently to hoist the saw cylinder out of the apparatus. No provision was made to break the circuit to the saw motor other than the on/off switch and the hydraulic cylinders used to open the gratefall had no backup to prevent uncontrolled pivoting of the gratefall during the opening process in case of a hydraulic failure. Thus, the prior system, while an improvement over earlier models was still cumbersome and dangerous.
[0008] The value or price of lint is determined by the purity of the lint fiber. The higher the foreign matter or “trash” such as broken hulls, kernels, etc. in the lint, the lower the quality. Therefore it is desirable to remove such trash from the lint in the delinter. “Moting”, the removal of trash (“motes”) from the lint, is accomplished by gravity in a moting chamber, where the heavier or more dense motes fall through an upwardly-flowing airstream created pneumatically to carry away the lint. As noted above, the value of both the seed and the lint is diminished if the seed spends too much time on the saw or is too compressed at the end of the saw cylinder such that the seed hull is torn.
[0009] Thus, it can be seen that conventional delinting apparatus currently in use suffers from a number of significant drawbacks. A need presently exists for eliminating these drawbacks, to yield delinting machinery which enables higher efficiency delinting and better quality lint than has previously been obtained.
SUMMARY OF THE PRESENT INVENTION
[0010] It is an object of the present invention to increase the capacity of the delinter over prior delinter designs while lowering energy consumption per ton of seed. Another object of the invention is to reduce the need to re-sharpen saws resulting in both longer saw life and saw sharpening file life. Still another object of the invention is decrease the amount of down time while re-sharpening each saw cylinder. A further object of the invention is to improve the quality of the lint. Yet another object of the invention is to reduce seed damage in the delinter. A significant object of the invention is to eliminate hydraulic and pneumatic cylinders in the gratefall operation to simplify and enhance the safety of the saw removal process.
[0011] These and other objects and advantages of the invention will become apparent from the following detailed description of the preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] An apparatus for delinting cottonseed is depicted in the accompanying drawings which form a portion of this disclosure and wherein:
[0013] FIG. 1 is a side elevation view of the delinter showing the drive components for the saw cylinder;
[0014] FIG. 2 is a side elevation view of the opposite side of the delinter showing the drive components for the float and doffing brush;
[0015] FIG. 3 is a front elevation view of the delinter
[0016] FIG. 4 a to 4 d are side elevation views showing the sequence of opening the gratefall and loosening the saw drive belt
[0017] FIG. 5 is a detail of the transition from the feeder to the gratefall
[0018] FIG. 6 is a detail of the float assembly.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] Referring to the FIGS. 1-4 for a clearer understanding of the invention, it may be seen that the preferred embodiment of the invention contemplates a delinter 10 having the same major components as the delinter shown in the '448 patent, namely a feeder 11 , a lint discharge 12 , a motes conveyor 13 , a seed conveyor 14 , a housing 20 , including various access doors and windows. A float 16 and chamber 17 is defined beneath feeder 11 within the housing 20 and above a saw cylinder 22 which carries a plurality of saws 24 . A doffing cylinder is provided to conventionally doff the lint from the saws.
[0020] In the '448 patent, the disclosed gratefall assembly supported the float and was linked to the saw cylinder supports such that opening the gratefall exposed the saw cylinder and moved it to a position where it could be hoisted vertically. However, the gratefall was moved between the open and closed positions by a hydraulic cylinder mounted outside the gratefall assembly. The drive belts for the float and the saw cylinder were tensioned by separate pneumatic cylinders. In that design the tension had to be released and the drive belts for both the float and saw removed before the gratefall could be opened. This required the operator to undertake several steps to open the gratefall including removing the belts while leaning over the motes and seed conveyors.
[0021] The present invention eliminates all hydraulic and pneumatic cylinders and releases the tension on the saw and float belts while the gratefall transitions from the closed to open position, thus eliminating several steps and allowing the operator to remove the belts as needed from the front of the machines and also eliminates or replaces other forms of removing saw cylinder. Referring to FIGS. 1 to 4 in the current design, saw motor 31 drives take-off belt 32 , to sheave 33 which is mounted to housing 11 at a fixed location. A saw belt 35 is also entrained about sheave 33 and saw drive sheave 36 which is mounted on saw pivot arms 38 on each side of the delinter are pivotally rotated with gratefall assembly 41 about the same axis passing through pivot shaft 39 , thus the saw drive sheave 36 is movable with the gratefall assembly 41 . Mounted to the saw cylinder pivot arm 38 and pivot shaft 39 , and interposed between sheave 33 and saw drive sheave 36 is the saw idler assembly 51 Saw idler assembly 51 includes a fixed idler bracket 52 pivotally mounted for movement about pivot shaft 39 in fixed relation to gratefall assembly 41 and a floating idler bracket 53 also mounted for movement about pivot shaft 39 at a selected angle offset from fixed idler bracket 52 . The offset between brackets 52 and 53 is maintained by rod adjustably connected there between. Bracket 52 carries a belt idler pulley 56 which engages saw belt 35 forwardly of pivot shaft 39 and bracket 53 carries a belt idler pulley 57 which engages belt 35 rearwardly of pivot shaft 39 and serves as a tensioning pulley. The tension on the belt is adjusted by varying the angle between brackets 52 and 53 . On the opposite side of the delinter 10 a float take-off belt 62 is driven by float motor 61 about a sheave 63 mounted to housing 11 at a fixed location. A float belt 65 is entrained about sheave 63 and float drive sheave 64 . A float idler assembly 71 which is the mirror image of saw idler assembly 51 and includes a fixed bracket 72 , floating bracket 73 , positioning rod, belt idler pulley 76 , and belt tensioning pulley 77 both of which engage the float belt 65 in the same manner as described above. It will be noted that pivot shaft 38 is offset from a direct line between sheaves 33 , 63 and drive sheaves 34 , 64 , thus engagement of belts 35 , 65 , by the idler pulleys 56 , 76 and 57 , 77 give the belts a L shaped configuration when properly tensioned.
[0022] A pair of jack screws 81 , 82 are mounted to the housing and connected to the pivot arms 38 to urge the pivot arms about the pivot axis in opening and closing the gratefall assembly 41 . An electric motor 83 elongates and shortens the jack screws. When the jack screws are elongated they urge the drive sheaves 34 , 64 carried by the gratefall assembly 41 away from the fixed sheaves 33 , 63 , thus making the L shape of the drive belts 35 , 65 more obtuse as shown in FIG. 2 a to 2 d and moving idler pulleys 56 , 76 closer to drive sheaves 33 , 63 thus releasing the tension on the belts 35 , 65 such that when the grate fall is completely open the saw belt 35 may be easily removed or replaced on the sheaves at a convenient level directly in front of the operator. The float belt 65 is loosened but does not need to be removed from the drive sheave to remove the saw cylinder. It should be therefore apparent that the operation of opening the gratefall and removing the saw cylinder for sharpening or maintenance is greatly simplified. Note that since the doffing roll is not mounted to the gratefall assembly 41 , it does not move and doffing roll belt 92 remains tensioned between sheave 63 and doffing drive sheave 93 , in as much as the float and doffing roller are driven by the same motor.
[0023] It should be noted that jackscrews 81 , 82 provide a positive mechanical linkage to the gratefall assembly 41 , thus if electrical power is lost during the movement of the gratefall the jackscrew will stop and the gratefall assembly will remain in its then current position rather than falling under the influence of gravity as could occur with a hydraulic system. It is also noteworthy that limit switches are in the circuit energizing saw motor 21 and float motor 22 . These limit switches open when the gratefall assembly begins to move from the closed position de-energizing the saw circuit and thus insuring that none of the belts, motors or sheaves are energized during the saw cylinder change out process.
[0024] It should be noted that feeder 11 is the same width as saw cylinder 22 , thus seed entering the float chamber 17 and urged toward the saws 24 is able to pass vertically through the delinter without the need to migrate laterally as was the case in the delinter shown in the '448 patent. Accordingly the seed can be processed more quickly and no build up or accumulation of seeds at any region across the saw cylinder 22 is encountered, thereby reducing the dwell time of the seed on the saws 24 and reducing the prospect of slicing the seed and contaminating the lint with hull or oil produced by the machine.
[0025] Aiding in the direct processing of the cottonseed from the feeder to the saws is the redesign of the entry to the float chamber 17 in the gratefall assembly 41 . The rear scroll 101 has been extended and turned nearly 90 degrees at the entrance from the feeder so that a smooth surface with no transitions between metal parts are presented except where the scroll 101 abuts frame plate 102 . Likewise, the seed board 103 has been redesigned to reduce friction at the inlet from the feeder 11 , by turning the upper edge of the plate forming the seed board away from the inlet, thereby eliminating a part to part transition and improving the flow characteristics of the cottonseed through the machine.
[0026] A further refinement in flow is achieved by adding end caps 101 to the float which rotate with the float vanes as seen in FIG. 6 . Traditional floats did not have endcaps thus creating friction and accumulation of cottonseed at the float vane and gratefall sideplate interface which exerts extra pressure against the gratefall side plates and forces most of the seed to be discharged at each end of the float chamber causing uneven delinting of the seed. By improving the flow of the cottonseed from the wider feeder through the smother entrance and across the more efficient float, the quality of the lint produced by the machine and the efficiency of the delinter is greatly improved. This is particularly so, when the saws 24 themselves are configured differently. More specifically, prior to the introduction of the '448 delinter the saw teeth were formed with a tangent line intersecting a 12″ diameter saw. The '448 design used an 18″ diameter saw with a tangent designed for that saw diameter, however, this saw tooth design was more likely to rip the seed hull. Thus, some prior art machines were retrofitted with 18″ diameter saws in on which the tangent line of the tooth was the same as had been used on a 12″ diameter saw. This reduced the damage to the hull considerably, but did not provide the efficient operation and significantly improved quality lint which is achieved when the feeder is widened, the float capped and the transition from feeder to gratefall is smoothed in addition to using the 12″ tangent line tooth on an 18″ saw.
[0027] It is to be understood that the form of the invention shown is a preferred embodiment thereof and that various changes and modifications may be made therein without departing from the spirit of the invention or scope as defined in the following claims. | A delinter apparatus for seed cotton includes a jack screw displacement system for a gratefall which opens the apparatus for removal of a saw cylinder while urging a plurality of belt tensioning idlers into a relaxed position such that the drive belt for the saw cylinder can be removed in a simplified and more efficient manner. The apparatus also has improved flow characteristics due to improvements in the lint feeder design as well as the transition designs from the feeder to the float chamber and saw interface. | 3 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to lights and light fixtures. More specifically, it relates to a suspended cable and reel assembly that allows a user to quickly and easily install a lighting system for positioning of decorative or utility lighting fixtures.
BACKGROUND OF THE INVENTION
[0002] Overhead lighting systems typically suspended from above such as by a ceiling fixture or by track lighting systems. Cable lighting systems have recently been developed to provide both power and support by conductors stretched across a plane bounded by two walls. These systems have become popular due to their simplicity, their functionality and their ability to place lamps suspended in areas that would normally be difficult to light. These systems allow a user to set up a suspended lighting system with a number of components and modify that system on demand. These cable lighting systems have also become commonplace in the United States and other countries for both utility and decorative lighting.
[0003] Most of theses systems are tensioned using multiple turnbuckles at each end of the conductors. One of these systems is disclosed in U.S. Pat. No. 5,158,360, issued to Banke. This system uses insulated cables stretched overhead between walls. The system is installed by common wall fasteners such as screws or sheetrock fasteners. The tension in these cables are adjusted by manually adjusting turnbuckles on either end. These systems require careful alignment of the attachment points and conductor cables on opposing walls. It is difficult to accomplish accurate alignment and consistent tensioning between the two conductors and thereby avoid an uneven plane. Fastening the cables securely and independently to varied surfaces is also difficult. This difficulty in turn may cause the lighting fixtures to be positioned at an undesired angle.
[0004] Another disadvantage of the system disclosed in U.S. Pat. No. 5,158,360 is the difficulty in modifying the arrangement of lighting fixtures once the system has been assembled. The tensioning method described above will often require the user to climb a ladder to reach the height of the conductor plane, and therefore be limited in movement for repositioning the lighting fixtures. The fixtures themselves are firmly held in place by cable clamps on both conductors, and are not retained once released, which requires the user to support the weight of the fixture until he or she can reposition the ladder at the desired location.
[0005] Other systems have tried to overcome these disadvantages by allowing the fixture to slide along the horizontal plane. One such system is disclosed in U.S. Pat. No. 5,440,469. This system, however, requires the use of rigid cylindrical conductors, that must be coupled together to reach the desired length, and do not allow the user to position the system between walls or other surfaces that are not parallel to each other.
[0006] Another such system is disclosed in U.S. Pat. No. 6,536,925. This system uses a separate supporting method and a plurality of S-hooks to achieve the desired movement. The disadvantages of this system are obvious, and include the appearance of unnecessary slack at the ends of each conductor, and the absence of any method for retracting and storing the unnecessary slack. This system also includes the limited ability to position the direction of the lamps once suspended from the cable assembly.
[0007] Another disadvantage of the prior art is the complexity of the hardware required for installation. One such system is disclosed in U.S. Pat. No. 6,244,733. This system requires multiple points of mounting on both the horizontal and vertical room surfaces. This system also limits the flexibility of the lighting system arrangement by imposing a rigid supporting method and heavy lighting fixtures and supports.
[0008] Another such system is disclosed in U.S. Pat. No. 5,340,322. This system also uses a rigid support and conductive member, which in turn also requires more support members and limits the options for the user to position the lighting fixtures. This system also has the disadvantage of not allowing the plane to be positioned between two room surfaces that are not parallel to each other.
[0009] In most cases, these prior systems require complicated mounting procedures using tools and an experienced installer. Licensed electricians are often needed to install the hard wired components safely. They require considerable mechanical skill in installation and maintenance. A need presently exists for a system that can be easily installed with little mechanical aptitude.
SUMMARY OF THE INVENTION
[0010] The present invention solves these problems and others by providing a cable lighting system that can be easily installed with little mechanical ability or tools. The cable lighting system can be installed in any location that has opposing walls or even adjacent walls. The cable lighting system provides an integrated preassembled lighting system that can be installed straight from the packaging without assembly or modification.
[0011] The cable lighting system of a preferred embodiment of the present invention provides a preassembled system that has the cables, anchoring systems, a tensioning system, electrical transformer and lighting fixtures already assembled. The user simply anchors a plaque holding one end of the cables to a first surface, the opposing end of the cables are held by a plaque to a second surface. Then the user adjusts the tension in the cables without tools, adjusts the position of the lighting fixtures by sliding and aiming them to the desired orientation and connects the power cord to an electrical outlet.
[0012] The cable lighting system of a preferred embodiment provides a cable tensioning system that independently adjusts the tension in each cable. This allows the system to be installed at an angle or on uneven surfaces.
[0013] The cable lighting system of a preferred embodiment incorporates the tensioning system within the housing of one of the anchoring systems. This provides a clean and elegant look the cable lighting system. The electrical transformer may be mounted within the housing as well.
[0014] In a preferred embodiment of the cable lighting system, the tensioning system includes cable reels mounted by way of independent ratchet mechanisms to each of the cables. The cables are pre wound onto the reels and pull out for installation. The reels are then turned to tension the cables independently. This allows the tension in each cable to be independently adjusted until the appropriate tension in each cable has been reached and maintained.
[0015] A preferred embodiment of the cable lighting system of the present invention provides an electrical transformer to create a low voltage system. The transformer can be mounted within a housing on one end of the cables, near the power source, within a recessed can, or at any location along the cables.
[0016] Other embodiments allow for other means to store, tension and lock the cables independently that do not include reels which will be further discussed.
[0017] These and other features of the present invention are evident from the drawings along with the detailed description of preferred embodiments.
BREIF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is an overview of a cable lighting system of a preferred embodiment of the present invention.
[0019] FIG. 2 is a rear view of the system of FIG. 1 .
[0020] FIG. 3 is an exploded view of the assembly of the system of FIG. 1 .
[0021] FIG. 4 is a view of a first step of mounting the system of FIG. 1 .
[0022] FIG. 5 is a detail view of the cable reel mechanism of the embodiment of FIG. 1 .
[0023] FIG. 6 is another detail view of the cable reel mechanism of the embodiment of FIG. 1 .
[0024] FIG. 7 is another detail view of the knob of the cable reel mechanism.
[0025] FIG. 8 is another detail view of the cable reel mechanism of the embodiment of FIG. 1 .
[0026] FIG. 9 is view of the operation of the cable reel mechanism of the embodiment of FIG. 1 .
[0027] FIG. 10 is another detail view of the operation of the cable reel mechanism of the embodiment of FIG. 1 .
[0028] FIG. 11 is cross section view of the cable reel mechanism.
[0029] FIG. 12 is a view of the second step of mounting the system of FIG. 1 .
[0030] FIG. 13 is a view of mounting the cable reel housing of the system of FIG. 1 .
[0031] FIG. 14 is a view of the completed system of the embodiment of FIG. 1 .
[0032] FIG. 15 is a top view of the system of FIG. 14 .
[0033] FIG. 16 is a perspective view of the system mounted at an angle.
[0034] FIG. 17 illustrates an alternative tensioning mechanism.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0035] The present invention provides a pre-assembled low voltage cable lighting system. It is to be expressly understood that this exemplary embodiment is provided for descriptive purposes only and is not meant to unduly limit the scope of the present inventive concept. Other embodiments, and variations of the conductors or lighting fixtures of the present invention are considered within the present inventive concept as set forth in the claims herein. For explanatory purposes only, the lighting apparatus of the preferred embodiments are discussed primarily for the purposes of understanding the method of installation. It is to be expressly understood that other devices are contemplated for use with the present invention as well.
[0036] A preferred embodiment of the present system is illustrated in FIGS. 1-16 . This preferred embodiment utilizes a low voltage cable lighting system 10 that comes pre-assembled and can fit most room sizes. In this preferred embodiment, the cable lighting system 10 includes two parallel braided electrically conductive cables 20 , 22 that are attached to opposing, or in some instances, adjacent walls or other surfaces. It is to be expressly understood that other types, numbers and configurations of conductive cable may be used as well.
[0037] Lighting fixtures 30 , such as pendants or other types of light fixtures, are secured between the electrical cables 20 , 22 for support and for receiving electrical current. It is to be expressly understood that these lighting fixtures may come in any configuration, size or shape that is appropriate for low voltage lighting, particularly those designed for cable lighting systems.
[0038] The cables 20 , 22 are secured on one surface by anchor plate 40 and on the other surface by cable reel mechanism 60 . A transformer may be separately housed in a dimmer mechanism adjacent an electrical outlet or in other locations. Alternatively, the transformer may be housed in the anchor plate 40 .
[0039] The anchor plate 40 , as shown in FIG. 1 , includes a plate 42 and adhesive mounting tape 44 . In the preferred embodiment, the plate 42 is mounted by the adhesive mounting tape 44 as shown in FIG. 4 by a pressure application system such as the system disclosed in U.S. patent application Ser. No. 11/426,574 incorporated herein by reference. Screws may be used along with the adhesive mounting tape to ensure a secure fastening of the anchor plate. The anchor plate can be secured to the wall surface by other mounting mechanisms as well such as by a screw through screw hole 46 , or by other attachment mechanisms. The mounting plate also includes holes 8 for receiving the cables 20 , 22 that are secured by clamps, knots, screws or other attachment mechanisms. The cables are electrically connected to an electrical source by an adhesive mounted electrical power cord, such as the power supply disclosed in U.S. Pat. Nos. 6,540,372 and 7,137,727, incorporated herein by reference or by other conventional power supplies.
[0040] The opposing ends of cables 20 , 22 are secured to other wall or surface by cable reel mechanism 60 . The cable reel mechanism includes exterior housing 62 . The housing 62 is mounted onto the surface by using an anchor plate 64 that is mounted to the wall surfaces by adhesive tapes 66 similar to the anchor plate 40 discussed above.
[0041] The cable reel mechanism 60 includes independent cable tightening mechanism 80 to independently tighten each of the cables 20 , 22 . The cable tightening mechanism 80 as shown in FIGS. 2 , 3 and 5 - 11 includes reels 82 , 84 having spools 86 , 88 for winding and unwinding the cables 20 , 22 , respectively. The reels 82 , 84 have knobs 90 , 92 that extend outside the housing or by detachable or hidden knobs. The inner surface of the reels 82 , 84 include ratchet mechanisms 94 , 96 and clips 98 , 100 respectively. The reels are inserted into openings on the sides of the housing so that the clips 98 , 100 engage through the apertures in a bracket in the housing to retain the reels within the housing. The cables 20 , 22 are inserted through cable holes 106 , 108 and tied inside the spools 86 , 88 .
[0042] The housing 62 includes resilient posts 110 , 112 , 114 , 116 formed inside the housing adjacent the ratchet mechanism 94 , 96 . The posts 110 , 114 are adjacent one another while posts 112 , 116 are adjacent one another at the other end of the housing. Knobs 90 , 92 are formed on the end of the reels 82 , 84 on the exterior of the housing.
[0043] When the knobs 90 , 92 are pulled outward or slightly extended from the housing, the ratchet mechanisms 94 , 96 engage with only the resilient posts 110 , 112 , respectively. This provides some friction against the ratchets 94 , 96 as shown in FIGS. 8 and 11 . This prevents the reels from freely unwinding the cables but allows the cables to be pulled from the reel in a relatively easy manner so the cables may be unwound during the installation process.
[0044] When the knobs 90 , 92 are pushed inward and retained by a clicking mechanism, the toothed ratchet mechanisms 94 , 96 engage with the second set of resilient posts, 114 , 116 respectively to provide additional friction as shown in FIGS. 9 , 10 and 11 . This allows the reel to be rotated in one direction only to wind the cables onto the reels and hold it securely so the cables are taught. The holding force of the posts can be overcome with sufficient cable pulling force in the event that the cable is snagged so as not to damage the system. Each of the reels operate independently relative to one another. This allows the cable reel housing 62 to be mounted at an angle relative to the anchor plate 42 as shown in FIG. 16 .
[0045] Other types of cable tightening mechanisms for the reels may be uses as well, such as coil springs, metal spring clips or any other mechanism that can apply friction to the cable in one setting and strong holding power in the other setting. In addition, a locking mechanism may be used to secure the cables that employ a cam lock, wedge lock or other locking device engaged once the cables are properly tensioned.
[0046] Other embodiments that do not use reels to hold the cables yet provide simple tensioning methods can also be used. These include but are not limited to mechanisms to coil or hold the cable so it can be let out for instillation, which might be outside the housing such as spools, loops and other means to organize the cables. These means use a locking mechanism such as a levered cam or push-in wedge to lock the cables once they are pulled tight by hand.
[0047] The cables 20 , 22 are engaged with electrical contact leads that are also attached to the transformer 100 . This supplies electrical current to the cables 20 , 22 and thus to the light fixtures 30 . The transformer may be mounted within the anchor mount 40 , on the wall and held by adhesive tape, plugs into the electrical power outlet, within a recessed ceiling can, junction box or other locations.
[0048] In this preferred embodiment, lighting fixtures 30 are preinstalled onto the cables 20 , 22 . The fixtures can be slid along the cables to the desired locations. In other embodiments, the light fixtures can be installed after the cables are installed and tensioned.
[0049] In use, the cable lighting system is attached by first securing the anchor plates 40 , 66 to the wall surfaces as shown in FIG. 3 . These wall surfaces can be opposing walls at any angle or even adjacent walls if there is an adequate angle. The distance between the wall surfaces is limited only by the amount of cable supplied.
[0050] The cable reel housing is pulled away from the mounted anchor plate 40 as shown in FIG. 12 . The cable reel housing 62 is then attached to the desired location on the opposing wall as shown in FIG. 13 . At this time, the cables 20 , 22 are under some tension but are relatively slack. The cable light fixtures 30 can then be adjusted to the desired location with the cables somewhat slack. They can also be moved when the system is under tension.
[0051] The knobs 90 , 92 are then pushed inward so the stronger tensioning post is engaged and rotated to tighten the cables as shown in FIG. 9 . The ratchet mechanism allows the individual cable reels to be operated so that a cable may reach the desired tension independently of the other cable. This allows the cables to be positioned so that the cables may have differing lengths, such as at an angle.
[0052] The power cord that supplies low voltage electricity is low profile, adhesive backed and attaches to the wall. It extends to a transformer with switch or dimmer installed in a housing that is adhesive mounted to the wall. It is then plugged into the electrical outlet, or plugged into a recessed ceiling can with a screw in adaptor. In other preferred embodiments, the system can be hardwired into existing junction boxes. The transformer, in one preferred embodiment, is mounted within a centrally located junction box and in other embodiments plugged directly into an electrical receptacle. The transformer can attach to the cables 20 , 22 at one end or in a central location.
[0053] In a preferred embodiment of the present invention, the cable lighting system is pre-assembled and distributed in a kit form. The user simply unpacks the pre-assembled system, as shown in FIG. 1 . The system may also be mounted to separate anchor plates at the desired locations, The user secures the two plaques with cables attached onto the anchor plates and tensions the cables by the use of the crank mechanism. There are little or no tools necessary and no mechanical skill is needed.
[0054] In another preferred embodiment of the present invention, the anchor plate and the cable reel housing may include plaques that are mounted to the wall by the adhesive tape and/or screws or other fasteners. The anchor plate and the cable reel housing are already pre-mounted on the cables. Once the plaques have been mounted onto the mounting surfaces, the anchor plate and the cable reel housing are simply slipped over the respective plaques and snap into place.
[0055] The above described embodiment disclosed using cables in a straight fashion. In other embodiments brackets may be used to redirect the cables around corners or in other directions. The tensioning mechanism is utilized to maintain the tension even with these brackets.
[0056] In another embodiment shown in FIG. 17 , an alternative embodiment of the tensioning mechanism is illustrated. The cables 20 , 22 are inserted into plate 160 that is mounted to the wall. The cables are pulled tight manually and locked into place by cord locks 162 , 164 . The excess cable may then be cut off or coiled and stored inside the housing.
[0057] Other tensioning mechanisms are also included within the scope of the claimed invention. It is to be expressly understood that the above described embodiments are intended for explanatory purposes and are not meant to limit the scope of the claimed inventions. | A suspended cable lighting system that is pre assembled and uses reels to house and tension the cable. This allows a user to quickly and easily assemble a lighting system for positioning of decorative or utility lighting fixtures without technical knowledge or tools. The system provides conductors which provide both power and support to a plurality of lighting fixtures, which may be suspended between opposing or adjacent walls, thereby creating various angles at which the lighting fixtures may be directed. The reel ratcheting assembly allows quick and simple tensioning of the conductors, and allows a user to relax the tension to gain access to the lighting fixtures for removal or repositioning without the use of tools. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to high conductivity high temperature copper alloys, and particularly to such alloys which are free from internal copper oxides.
Oxygen free copper must be used in applications where the alloy is to be annealed in a hydrogen containing atmosphere, as the presence of oxygen in either its elemental state or as copper oxide results in the formation of water vapor during the annealing process which causes embrittlement of the alloy.
Two major methods are used to reduce the oxygen level of copper so as to avoid embrittlement. The first method involves casting the alloy in an inert atmosphere and fluxing the molten copper with an inert gas to reduce the oxygen level. This is a complex process and difficult to perform satisfactorily. The other major method of deoxidizing copper consists of adding a reactive material to the melt which will form an oxide in preference to copper oxide. The reactive material is chosen so that its oxide will be stable and will not be reduced by hydrogen during annealing. Unfortunately, most of the reactive materials used have a highly deleterious effect on electrical conductivity if excess reactive material remains in solution in the deoxidized copper alloy. Because of the reactive nature of the materials used, it is difficult to accurately control the amount of reactive material which is actually needed to deoxidize the molten copper without causing a loss of conductivity.
In addition to the above, it is known that oxygen free copper has relatively low mechanical properties and it is highly desirable to improve these properties while simultaneously maintaining a high electrical conductivity. Further, oxygen free copper has a very low softening point and for many applications it would be highly desirable to maximize strength and conductivity and to increase the softening temperature. Finally, care must be taken in the processing of oxygen free copper to avoid the reintroduction of oxygen into the alloy. For example, when welding oxygen free copper, an inert atmosphere must be used so as to protect the molten material in the weld zone from oxidation.
Mischmetal has been used as a deoxidizing material in the production of oxygen free copper, however, when excess mischmetal is present a low melting point eutectic forms between Cu and CeCu6 compound which results in an alloy which is unsuitable for high temperature brazing and other similar applications where high temperatures are encountered.
SUMMARY OF THE INVENTION
In accordance with the present invention, copper base alloys possessing high conductivity and temperature stability together with freedom from internal copper oxides are prepared which contain mischmetal or lanthanides in place thereof, and phosphorus with the balance essentially copper. Mischmetal content of the alloys of the present invention ranges from 0.03 about 0.5% and the phosphorus content will range from about 0.01 to about 0.1%. The phosphorus and mischmetal contents of the present invention are interrelated, and a specific ratio of mischmetal to phosphorus must be maintained for improved results.
The alloys of the present invention are characterized by improved oxidation resistance in high temperature contact with air. Since the preparation in accordance with the present invention employs a chemical deoxidizing technique, the alloys are resistant to internal copper oxide formation and subsequent hydrogen embrittlement during hot processing or other elevated temperature exposure. This is a significant advantage over high purity copper produced by a mechanical type of degassing operation which is susceptible to surface oxidation and internal formation during thermal applications such as welding conducted in oxygen containing atmosphere.
The alloys of the present invention likewise exhibit improved properties in comparison with conventionally produced oxygen free copper and copper which has been deoxidized with mischmetal alone. Increases on the order of 50°C are observed in softening temperatures and improvements are noted in tensile properties.
Accordingly, it is a principal object of the present invention to provide a copper base alloy in the deoxidized condition which possesses high conductivity and thermal stability.
It is a further object of the present invention to provide a copper base alloy as aforesaid which is easily and inexpensively fabricated.
It is yet a further object of the present invention to provide an alloy as aforesaid which is resistant to surface and internal oxidation during high temperature contact with oxygen containing atmosphere.
Further objects and advantages will be apparent after a consideration of the invention proceeds with reference to the description and the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graph comparing ultimate strength and conductivity against excess mischmetal and phosphorus contents of the alloys of this invention.
FIG. 2 is a graph comparing ultimate tensile strength against annealing temperature for alloys which were cold rolled 75%.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In accordance with the present invention the foregoing objects and advantages are readily obtained.
The alloys of the present invention are copper base alloys comprising mischmetal and phosphorus, with the balance essentially copper. The mischmetal content ranges from about 0.03 to about 0.5% and preferably from about 0.05 to about 0.4%, and the phosphorus content ranges from about 0.01 to about 0.1% and preferably from about 0.02 to about 0.1%. Quantities of mischmetal less than those specified above are insufficient to insure complete and uniform deoxidation of the copper, and there is little or no benefit to be obtained from exceeding the above specified values. Mischmetal is a mixture of rare earth metals which comprise Elements Nos. 58-71 on the Periodic Table. A typical mischmetal composition is listed below:
Cerium 50%Lanthanum 27%Neodymium 16%Praseodymium 5%Other Rare Earth Metals 2%
As used in this application, the term mischmetal is intended to include any material comprised predominantly of lanthanide regardless of the relative proportions thereof. For example, cerium alone could be used in place of mischmetal and would provide equally satisfactory results.
The present invention utilizes mischmetal and phosphorus in combination, as the excess of both elements present after the deoxidation of the copper react to form an intermetallic compound and thereby remove themselves from solid solution. This compound formation eliminates the incipient melting problem associated with the use of mischmetal and likewise the conductivity problem experienced with phosphorus. By controlling the ratio of excess mischmetal to excess phosphorus, the properties of the final alloy may be accurately predicted, and alloys possessing a wide range of properties may be prepared.
The aforenoted ratio of mischmetal to phosphorus corresponds to the stoichiometric weight ratio required to form the compound CeP which is 4.52:1, mischmetal:phosphorus. When excess mischmetal is present, there is no deleterious effect on strength or conductivity, however, when the amount of mischmetal exceeds 0.05% of the stoichiometric ratio, incipient melting occurs, which is a problem experienced in high temperature applications such as, for example, brazing or spot welding. This incipient melting is believed to be caused by a formation of a low melting point eutectic between the compound CeCu 6 and Cu.
The preceding discussion has assumed that the compounds formed are based on cerium, however, it can be appreciated that because of the great chemical similarity between the lanthanides, analogous compounds can be formed which are based on other members of that series which will possess similar characteristics.
If the achievement of high conductivity in the alloys of this invention is important, excess phosphorus should be avoided because of the strong deleterious effect of phosphorus on conductivity. FIG. 1 shows the effect of excess phosphorus and excess mischmetal on ultimate tensile strength in a copper base alloy containing mischmetal and phosphorus. It can be seen that excess phosphorus has a strong negative effect on conductivity which may be characterized by the following equation: conductivity (IACS) equals 93 minus the quantity 535 times excess phosphorus. Likewise, phosphorus has an effect on ultimate tensile strength with the result that excess phosphorus increases ultimate tensile strength in a manner approximately given by the following equation: ultimate tensile strength (KSI) equals 72 plus the quantity 175 times excess phosphorus. Accordingly, if conductivity is important the alloy should be produced to contain excess mischmetal, and if exposure to temperatures above 860°C is contemplated, the excess mischmetal should be limited to 0.05% maximum. However, alloys having a range of desirable properties may be obtained by providing excess phosphorus, and these alloys may be determined by reference to FIG. 1 and the preceding equations.
FIG. 2 shows high temperature behavior of the alloys of the present invention for one hour exposure time. It can be seen that alloys containing a combination of phosphorus and mischmetal have a softening temperature approximately 50°C higher than the softening temperature of conventional oxygen free copper and copper containing mischmetal alone. This added softening resistance is a useful property of the alloys of the present invention and permits them to be used in applications where conventional oxygen free coppers are not satisfactory.
The alloys of the present invention possess a further significant advantage over conventionally prepared oxygen free copper in that they retain their resistance to oxide formation even when exposed to high temperature in air, as for example in a welding application, since the mischmetal and phosphorus which remain in the alloy will oxidize in preference to the copper constituent. Accordingly, even after the alloy has been welded in air it may be annealed in hydrogen without embrittlement.
The alloys of the present invention are generally processed in accordance with conventional practice with the exception of the addition of alloying elements. Because of the reactive nature of the additives involved, it is preferable to add the mischmetal in a continuous form immediately before the molten metal enters the mold. This form of addition is particularly practical in a continuous casting operation. Reference is made to U.S. Pat. No. 3,738,827 which deals with this subject and which is assigned to the assignee of the present invention. Because phosphorus is also reactive, it may be added in a similar fashion, however, such is not absolutely necessary and the phosphorus may be added in bulk form to the molten metal. Subsequently, casting of the alloys of the present invention may be performed using conventional techniques and, in general, the methods used will be similar to those used for other high copper alloys.
The present invention will be more readily understandable from a consideration of the following illustrative examples.
EXAMPLE I
Alloys of various compositions were prepared by melting copper and adding the elemental additions wrapped in copper foil be rapidly submerging the addition below the surface of the melt. After stirring for one to two minutes, the melts were poured by the Durville process. The alloys were hot rolled in a temperature range of 300° to 800°C and several samples were subjected to various cold rolling and annealing sequences in preparation for subsequent testing. The various compositions prepared are set forth in Table I, below.
TABLE I______________________________________ANALYSIS AND HOT ROLLED CONDUCTIVITYOF EXPERIMENTAL ALLOYSAlloy *MM **P M:P Conductivity Wt. % Wt. % Ratio % IACS______________________________________X95 0.11 -- -- 96.5X96 0.02 -- -- 95.01431 0.05 -- -- 98.01600 0.11 0.005 22 98.01586 0.12 0.006 20 97.01588 0.05 0.008 6.25 95.01602 0.10 0.020 5.0 92.51696 0.14 0.030 4.67 94.01697 0.32 0.074 4.32 92.01599 0.10 0.024 4.17 92.51430 0.10 0.032 3.13 89.01586 0.10 0.044 2.27 84.01589 0.06 0.038 1.58 78.01429 0.09 0.054 1.53 73.01587 0.08 0.075 1.07 63.01590 0.05 0.082 0.6 61.0______________________________________ *MM - Mischmetal **P - Phosphorus
EXAMPLE II
Samples prepared in accordance with Example I were tested for their ability to avoid incipient melting at 900°C. The samples were heated to temperature and observed, and the results were noted and are presented in Table II, below.
TABLE II______________________________________DETERMINATION OF INCIPIENT MELTING900°C EXPOSURE FOR 10 MINUTES TO ONE HOURAlloy Composition, Wt. % Excess MM, IncipientCu *MM P Wt. %** Melting______________________________________X96 bal 0.02 -- 0.02 No1430 bal 0.05 -- 0.05 NoX95 bal 0.11 -- 0.11 Yes1429 bal 0.09 0.054 None No1696 bal 0.14 0.030 0.004 No______________________________________ *Mischmetal- **Represents MM content not participating as rare earth phosphides. Phosphides have a stoichiometric MM/P ratio of 4.52 to 1.
Referring to the table, it was observed that the samples possessing a mischmetal content above 0.05 weight percent exhibited incipient melting during exposure even for brief periods at 900°C. It was noted, however, that the addition of phosphorus coupled with the presence of mischmetal not exceeding 0.05 weight percent above CeP stoichiometry in accordance with the present invention prevented the occurrence of incipient melting.
EXAMPLE III
Additional samples prepared in accordance with Example I were tested by being cold worked 75 and 90%, respectively, and then heated to determine their resistance to softening. Samples of oxygen free high conductivity copper (OFHC) and silver-bearing copper Alloy No. 129 were similarly tested for purposes of comparison. Results of these tests are presented in Table III, below.
TABLE III______________________________________Alloy One Hour Softening* Temperature°C After 75% Cold Rolling______________________________________OFHC 215X95 260X96 2301430 3251429 330Alloy One Hour Softening* Temperature°C After 90% Cold Rolling______________________________________129 3151696 3251697 330Alloy Time to Soften** at 395°C______________________________________129 less than 5 minutes1697 71/2 minutes *50% drop in 0.2% YS **50% drop in R30T Hardness
It can be seen that the softening temperature of sample No. 1430, representing an alloy of the present invention exceeded the observed temperature of OFHC by approximately 110°C. Likewise, in the tests conducted after 90% cold rolling, the alloys of the present invention exceeded conventional Alloy No. 129 by as much as 15°C and resisted softening at 395°C for an additional 21/2 minutes. The above results clearly illustrate the improved resistance to softening exhibited by the alloys of the present invention.
EXAMPLE IV
Additional tensile testing was conducted between selected alloys prepared in accordance with Example I and commercial OFHC copper and DHP copper (phosphorus deoxidized, high residual phosphorus). The samples were tested for mechanical properties and conductivity at 90% cold rolling. The results of these tests, together with the respective materials and their compositions are set forth in Table IV, below.
TABLE IV__________________________________________________________________________MECHANICAL PROPERTIES AND CONDUCTIVITYAT 90% COLD ROLLING P MM CU Ultimate Tensile 0.2% Yield ConductivityAlloy Wt. % Wt. % Wt. % Strength, ksi Strength, ksi % IACS__________________________________________________________________________X95 -- 0.11 bal. 65 62 96.51696 0.03 0.14 bal. 69 66 9414290.054 0.09 bal. 75 72 73OFHC -- -- bal. 66 63 99DHP* 0.02 -- bal. 64 -- 85**__________________________________________________________________________ *Data for DHP copper is from A.S.M. Metals Handbook Vol. I, pages 1010-1011, Table 2. **Annealed conductivity
From the above table, it can be seen that the alloys of the present invention achieve comparable levels of strength and conductivity with a savings in cost of materials and processing.
The alloys of this invention have particular application for structural electrical components such as electrical contacts, electrical receptacles, electrical connectors and the like
All of the compositions specified in this application are given in percentage by weight.
This invention may be embodied in other forms or carried out in other ways without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered as in all respects illustrative and not restrictive, the scope of the invention being indicated by the appended claims, and all changes which come within the meaning and range of equivalency are intended to be embraced therein. | A high conductivity high temperature copper alloy containing mischmetal and phosphorus in a specific ratio. The alloy is free from internal copper oxides and is suitable for applications requiring stability at elevated temperatures. Strengths on the order of 70 KSI and conductivities on the order of 90% IACS are obtainable in cold worked material. | 2 |
TECHNICAL FIELD
[0001] The invention relates to a method for optimizing the specific fuel consumption, in short Cs, of a helicopter equipped with two turbo-engines, as well as a twin-engine architecture equipped with a control system for implementing such method.
[0002] Generally, at a cruising power, the turbo-engines operate at low power levels, under the maximum continuous power thereof, in short MCP (for Maximum Continuous Power). Such cruising power is equal to about 50% of their maximum take-off power, in short MTOP (for Maximum Take-Off Power). Such low power levels lead to a specific fuel consumption of about 30% higher than the Cs at MTOP, and thus a fuel over-consumption at a cruising power.
[0003] A helicopter is provided with two turbo-engines, each being oversized so as to be able to maintain the helicopter in flight in case of a failure in the other engine. At such operation powers dedicated to the management of an inoperative engine, so-called OEI (for One Engine Inoperative) powers, the valid engine provides a power being well beyond its nominal rating so as to allow the helicopter to face up to a dangerous situation, and then to continue its flight. Now, each rating is defined by a power level and a maximum use time. The fuel flow rate being injected into the combustion chamber of the valid turbo-engine is then substantially increased at OEI power to provide such extra power.
STATE OF THE ART
[0004] Such oversized turbo-engines are penalizing in mass and in fuel consumption. To reduce such fuel consumption at a cruising power, it is possible to stop one of the turbo-engines. The operating engine then operates at a higher power level and thus at a more advantageous Cs level. However, this practice goes against the present certification regulations and the turbo-engines are not designed to guarantee a restart reliability rate compatible with the safety standards.
[0005] For example, the restart time of the turbo-engine in standby mode is typically of about 30 seconds. Such time can be insufficient according to the flight conditions, for example at low flight height with a partial failure of the engine being initially active. If the standby engine does not restart in time, the landing with the engine in trouble can become critical.
[0006] More generally, the use of only one turbo-engine comprises risks in every flight circumstance where it is necessary to have an extra power available requiring in terms of safety to be able to use both turbo-engines.
DISCLOSURE OF THE INVENTION
[0007] The invention aims at reducing Cs so as to tend towards the Cs at MTOP power, while keeping the minimum safety conditions of power to be provided for any type of mission, for example for a mission comprising a search phase at low altitude.
[0008] To do so, the invention aims at using a twin-engine system in connection with particular means adapted for guaranteeing reliable restarts.
[0009] More precisely, the present invention aims at a method for optimizing the specific fuel consumption of a helicopter equipped with two turbo-engines, each comprising a gas generator provided with a combustion chamber. At least one of the turbo-engines is adapted to operate alone at a so-called continuous stabilized flight speed, the other engine being then at a so-called over-idle nil power speed adapted to switch into an acceleration mode of the gas generator of such engine through a driving being compatible with an emergency restart. Such emergency restart is carried out, in case of a failure of at least a previous conventional restart try, through an emergency mechanical assistance to the gas generator, produced by an autonomous on-board power dedicated to such restart. In case of a failure in the turbo-engine being in operation alone, the other over-idling turbo-engine is restarted by the emergency assistance.
[0010] The rotation speed of the gas generator in the over-idling turbo-engine stays substantially lower than the rotation speed of the idling gas generator usually applied to the turbo-engines.
[0011] A continuous speed is defined by a non limited time and thus does not relate to the transitory phases of take-off, stationary flight and landing. For example, for shipwrecked people being searched, a continuous speed relates to the cruising flight phase towards the search area and to the low altitude flight phase with the search area above water and to the cruising flight phase for return towards the base.
[0012] However, a selective use of the turbo-engines according to the invention, depending on the phases and flight conditions, other than the transitory phases, enables to obtain optimized performances in terms of consumption Cs with powers being close to the MTOP, but lower than or equal to the MCP, while facing up the failure and emergency cases through safe restart means of the turbo-engine at over-idling.
[0013] A rating output from an over-idle towards an active rating of the “twin-engine” type is triggered in a so-called “normal” manner. When an in-flight speed change imposes to switch from one to two engines, for example, when the helicopter switches from a cruising speed to a stationary flight, or in a so-called “emergency” manner in the case of an engine failure or in difficult flight conditions.
[0014] According to particular embodiments:
[0015] the over-idle speed is selected between a rotation keeping speed of the engine with the combustion chamber being ON, a rotation keeping speed of the engine with the combustion chamber being OFF and a nil rotation speed of the engine with the combustion chamber being OFF;
[0016] in a “normal” output of the over-idle rating, the chamber being ON, a variation of the fuel flow rate according to a protection law against pumping and thermal runaway drives the gas generator of the turbo-engine into acceleration up to the twin-engine power level, or
[0017] the chamber being OFF, an active drive leads the gas generator to rotate according to a pre-positioned speed within an ignition window, in particular according to a speed window of an order of the tenth of the nominal speed, then, once the chamber being ON, the gas generator is accelerated as previously, or
[0018] the chamber being OFF, the gas generator is driven by an electrical equipment adapted for such generator, such equipment starts it and accelerates it until its rotation speed is with an ignition window of the chamber, then, once the chamber is ON, the gas generator is again accelerated as previously;
[0019] at an over-idling speed within a chamber being OFF, an extra firing of the combustion chamber, i.e. in addition to a conventional firing, can be triggered;
[0020] in an emergency output of an over-idle speed with the chamber being OFF, the gas generator being at the rotation speed thereof within the ignition window of the combustion chamber, the chamber is ignited, then the gas generator is accelerated by the emergency assistance device;
[0021] the turbo-engines providing unequal maximum powers, the turbo-engine with the lowest power operates alone when the total power required is lower than its MCP, in particular during a low altitude flight rating of the search phase type;
[0022] the powers of the turbo-engines present a power heterogeneity ratio at least equal to the ratio between the highest OEI rating power of the turbo-engine with the lowest power and the MTOP power of the most powerful turbo-engine;
[0023] the heterogeneity ratio is comprised between 1.2 and 1.5 to cover a set of typical missions; preferably, such ratio is at least equal to the ratio between the highest OEI rating power of the turbo-engine of smaller power and the MTOP power of the most powerful turbo-engine;
[0024] a firing with a quasi instantaneous effect complementary to a conventional plug ignition can be triggered to ignite the combustion chamber in an emergency output;
[0025] the mechanical assistance energy, in an emergency output of an over-idle speed, is selected amongst energies of hydraulic, pyrotechnical, anaerobic, electrical, mechanical and pneumatic nature;
[0026] the emergency assistance is disconnected after the restarting of the valid engine;
[0027] the emergency assistance is preferably of an exceptional use, the activation thereof being able to be followed by a maintenance action for the substitution thereof.
[0028] According to advantageous embodiments:
[0029] two turbo-engines defining MTOP powers on take-off, provide substantially different powers presenting a heterogeneity ratio of powers being at least equal to the ratio between the highest OEI speed power of the turbo-engine of lower power and the MTOP power of the most powerful turbo-engine; one of the turbo-engines being able to operate alone in a continuous speed, the other engine being then in a standby mode with a nil power and the combustion chamber being OFF, while staying kept in rotation by the driving in view of an emergency restart;
[0030] both turbo-engines operate together during the transitory phases of take-off, stationary flight and landing; and
[0031] the turbo-engine of the lowest power operates alone when the total power being required is lower than or equal to its MCP.
[0032] The invention also relates to a twin-engine architecture equipped with a control system for the implementation of such method. Such architecture comprises two turbo-engines each equipped with a gas generator and a free turbine transmitting the available power up to the available maximum powers. Each gas generator is provided with means adapted for activating the gas generator in an over-idle speed output, comprising rotation driving means and acceleration means of the gas generator, firing means with a quasi instantaneous effect, complementary to the conventional plug firing means, and an emergency mechanical assistance device comprising an on-board autonomous energy source. The control system monitors the driving means and the emergency assistance devices of the gas generator depending on the conditions and the flight phases of the helicopter according to a mission profile previously registered in a memory of this system.
[0033] Advantageously, the invention can cancel the existence of OEI speeds on the most powerful turbo-engine.
[0034] According to preferred embodiments:
[0035] the active driving means of a gas generator can be selected between an electrical starter equipping such gas generator, supplied by an on-board mains or a starter/generator equipping the other gas generator, an electrical generator driven by a power transfer box, in short a so-called PTB, or directly by the free turbine of the other turbo-engine, and a mechanical driving device coupled with such PTB or such free turbine;
[0036] the complementary firing means can be selected between a glow plug device with laser rays and a pyrotechnical device;
[0037] the on-board autonomous source is selected amongst supplying sources of the hydraulic, pyrotechnical, pneumatic, anaerobic combustion, electrical (in particular through a dedicated battery or super-condensers) and mechanical type, including by a mechanical power group connected to the rotor.
SHORT DESCRIPTION OF THE FIGURES
[0038] Other aspects, characteristics and advantages of the invention will appear in the following description, related to particular embodiments, referring to the accompanying drawings wherein, respectively:
[0039] FIG. 1 is a diagram representing an exemplary power profile required during a mission comprising a search phase and two cruising phases;
[0040] FIG. 2 shows a simplified schema of an exemplary twin-engine architecture according to the invention; and
[0041] FIG. 3 shows a command diagram of a control system according to the invention depending on the flight conditions upon a mission having the profile shown on FIG. 1 .
DETAILED DESCRIPTION
[0042] The terms “engine” and “turbo-engine” are synonymous in the present specification. In the embodiment being illustrated, the engines have differentiated maximum powers. Such embodiment allows advantageously the OEI speeds to be cancelled on the most powerful turbo-engine, thereby minimizing the mass difference between the two engines. To simplify the language, the most powerful engine or oversized engine also can be designated by the “big” engine and the lowest power engine by the “small” engine.
[0043] The diagram illustrated on FIG. 1 represents the total power variation Pw being required as a function of time “t” to carry out a mission of recovering shipwrecked people with the help of a twin-engine helicopter. Such mission comprises six main phases:
[0044] one take-off phase “A” using the maximum power MTOP;
[0045] one cruising flight phase “B” up to the search area carried out at a power level being lower than or equal to the MCP;
[0046] one search phase “C” in the search area at low altitude above water, which can be carried out at a power and thus at a flight speed minimizing the hour consumption so as to maximize the exploration time;
[0047] one shipwrecked people recovering phase “D” in a stationary flight requiring a power of the other of the power used at take-off;
[0048] one return phase to the base “E”, being comparable to the cruising flight out “B” in terms of duration, power and consumption; and
[0049] one landing phase “F” requiring a power slightly higher than the power in the cruising phase “B” or “E”.
[0050] Such a mission covers every phase that can be carried out conventionally during a helicopter flight. FIG. 2 schematically illustrates an exemplary twin-engine architecture of a helicopter enabling to optimize the consumption Cs.
[0051] Each turbo-engine 1 , 2 comprises conventionally a gas generator 11 , 21 and a free turbine 12 , 22 supplied by the gas generator to provide power. At take-off and in continuous speed, the power being supplied can reach predetermined maximum values, respectively MTOP and MCP. A gas generator conventionally consists in air compressors “K” in connection with a combustion chamber “CC” for the fuel in the compressed air, which compressors supplying gases providing kinetic energy, and in turbines for a partial expansion of such gases “TG” driving into rotation the compressors via driving shafts “DS”. The gases also drive the free power transmission turbines. In the example, the free turbines 12 , 22 transmit the power via a PTB 3 that centralizes the power supplied to the loads and accessories (rotor driving, pumps, alternators, starter/generator device, etc.).
[0052] The maximum powers MTOP and MCP of the turbo-engine 1 are substantially higher than the powers the turbo-engine 2 is able to supply: the turbo-engine 1 is oversized in power with respect to the turbo-engine 2 . The heterogeneity between the two turbo-engines, corresponding to the ratio between the highest OEI speed power of the turbo-engine 2 and the maximum power MTOP of the turbo-engine 1 , is equal to 1.3 in the example. The power of a turbo-engine refers here to the intrinsic power, such turbo-engine can supply at most at a given speed.
[0053] Alternatively, both turbo-engines 1 and 2 can be identical and the maximum powers MTOP and MCP of such turbo-engines are then also identical.
[0054] Each turbo-engine 1 , 2 is coupled with driving means El and E 2 and with emergency assistance devices U 1 and U 2 .
[0055] Each means E 1 and E 2 driving into rotation the respective gas generator 11 , 21 , consists here in a starter respectively supplied by a starter/generator device equipping the other turbo-engine. And each emergency assistance device U 1 , U 2 advantageously comprises, in this example, glow-plugs as a firing device with a quasi instantaneous effect, in addition to the conventional plugs, and a propergol cartridge supplying an additional micro-turbine as an acceleration mechanical means for the gas generators. Such extra firing device can also be used in a normal output for a flight speed change, or in an emergency output in the over-idling speed.
[0056] In operation, such driving means E 1 , E 2 , the emergency assistance devices U 1 , U 2 and the commands of the turbo-engines 1 and 2 are managed by activation means of a control system 4 , under the control of the general digital command device for the motorization known under the acronym FADEC 5 (for “Full Authority Digital Engine Control”).
[0057] An exemplary management implemented by the control system 4 , in the field of a mission profile such as above indicated and registered in a memory 6 amongst others, is illustrated on FIG. 3 . The system 4 selects amongst a set of management modes MO the management modes adapted for the mission profile selected in the memory 6 , here four management modes for the mission being considered (as a profile illustrated on FIG. 1 ): one mode M 1 relative to the transitory phases, one mode M 2 relative to the flights at continuous speed—cruising and search phases—, one mode M 3 relative to the engine failures, and one mode M 4 for managing the emergency restarts of the engines in an over-idling rating.
[0058] Such mission comprises as transitory phases the phases A, D and F, respectively, of take-off, stationary flight and landing. Such phases are managed by the mode M 1 of twin-engine conventional operation, in which the turbo-engines 1 and 2 are both operating (step 100 ), so that the helicopter has a high power available, being able to reach their MTOP. Both engines operate at the same relative level of power with respect to their nominal power. The failure cases of one of the engines are conventionally managed, for example by arming the OEI ratings of the “small” turbo-engine 2 of the lowest power in the case of a failure of the other turbo-engine.
[0059] The continuous flight corresponds, in the reference mission, to the phases of cruising flight B and E and to the search phase C at low altitude. Such phases are managed by the mode M 2 that provides the operation of one turbo-engine while the other turbo-engine is in an over-idling speed and kept in rotation while the chamber is OFF by driving means, at a firing speed located within its preferential window.
[0060] Thus, in the cruising phases B and E, the turbo-engine 1 operates and the other turbo-engine 2 is kept in rotation through its starter being used as driving means E 2 and supplied by the starter/generator of the turbo-engine 1 . The rotation is adjusted on a preferential ignition speed of the chamber (step 200 ). Such configuration corresponds to the power need that, in such cruising phases, is lower than the MCP of the “big” engine 1 and higher than the MCP of the “small” engine 2 . In parallel, as regards the consumption Cs, this solution is also advantageous, since the big engine 12 operates at a higher relative power level than in a conventional mode, with both engines in operation. When the engines are identical, the power need in such cruising phases cannot exceed the MCP of the engines.
[0061] In the search phase C, the “small” turbo-engine 2 of the lowest power operates alone, since it is able to provide the power need itself alone. Indeed, the need is then substantially lower than the MCP power of the oversized turbo-engine 1 , but also lower than the MCP of the “small” engine 2 . But, mainly, the consumption Cs is lower, since this “small” engine 2 operates at a higher relative power level than the level at which the turbo-engine 2 would have operated. In such phase C, the turbo-engine 1 is kept in an over-idling speed, for example in rotation through the starter used as a driving means E 1 at a preferential chamber ignition speed (step 201 ).
[0062] Alternatively, in the case of engines of the same power, only one of both engines operates, the other being kept in an over-idling speed.
[0063] Advantageously, the mode M 2 also manages the conventional restart of the engine in an over-idling speed when the phases B, E or C are close to come to the end. If this conventional restart fails, the mode switches to the mode M 4 .
[0064] The mode M 3 manages the failure cases of the engine used by re-activating the other engine through its emergency assistance device. For example, when the oversized turbo-engine 1 , used in operation alone during the phases of cruising flight B or E, fails, the “small” engine 2 is quickly re-activated via its emergency assistance device U 2 (step 300 ). On the same way, if the “small” engine 2 alone in operation during the search phase C fails, the “big” engine 1 is rapidly re-activated via its emergency assistance device U 1 (step 301 ).
[0065] Such mode M 3 also manages for a long time such cruising or searching phases when the engine initially provided in operation has failed and has been substituted by the other engine being reactivated:
[0066] in the case of the cruising phases B and E, the emergency assistance device U 2 is disconnected, the OEI ratings of the “small” engine 2 being armed in accordance with the safety certifications (step 310 ) in case of differentiated engines;
[0067] for the search phase C (step 311 ), the emergency assistance device U 1 is disconnected, the MTOP of the oversized engine 1 being at least equal to the power of the highest OEI rating of the “small” engine 2 in the case of differentiated engine.
[0068] When the flight conditions become abruptly difficult, a quick restart of the engine in an over-idling speed by activation of the assistance device thereof can be opportune to derive benefit from the power of both turbo-engines. In the example, such device is of a pyrotechnical nature and consists in a propergol cartridge supplying a micro-turbine.
[0069] Such cases are managed by the emergency restart mode M 4 . Thus, whatever it is during the phases of cruising flight B and E (step 410 ) or during the search phase C (step 411 ) upon which only one turbo-engine 1 or 2 operates, the operation of the other turbo-engine 2 or 1 is triggered by the activation of the respective pyrotechnical assistance device U 2 or U 1 , only in case of a failure of the conventional restart means U 0 (step 400 ). The flight conditions are then secured by the operation of the helicopter in twin-engine mode.
[0070] The present invention is not limited to the examples described and represented. In fact, the invention applies as well to turbo-engines with either differentiated or equal powers.
[0071] Moreover, other over-idling speeds than the above mentioned speeds—namely keeping in rotation the engine whatever the chamber is OFF or ON, the rotation speed being advantageously within the ignition window if the chamber is OFF, or a nil rotation speed with the chamber being OFF, the rotation being then advantageously produced by the own starter of the engine supplied by the on-board mains can be defined: in the chamber being ON with a nil rotation speed of the engine, or still with a chamber in an ignition standby or partially ON with a nil or not nil rotation speed of the relative engine.
[0072] Furthermore, the control system can provide more or less than four management modes. For example, another mode or an extra management mode may be to take the geographical conditions (mountains, sea, desert, etc.) into account.
[0073] It is also possible to add other management modes, for example per flight phase or per structure (engines, driving means, emergency assistance devices) depending on the profiles of the mission.
[0074] Furthermore, at least one of the assistance devices can not to be provided for a sole use so as to enable at least another restart through this device upon the same mission. | A method and architecture to reduce specific fuel consumption of a twin-engine helicopter without compromising safety conditions regarding minimum amount of power to be supplied, to provide reliable in-flight restarts. The architecture includes two turbine engines each including a gas generator and with a free turbine. Each gas generator includes an active drive mechanism keeping the gas generator rotating with a combustion chamber inactive, and an emergency assistance device including a near-instantaneous firing mechanism and mechanical mechanism for accelerating the gas generator. A control system controls the drive mechanism and emergency assistance devices for the gas generators according to the conditions and phases of flight of the helicopter following a mission profile logged beforehand in a memory of the system. | 5 |
BACKGROUND OF THE INVENTION
I. Field of the Invention
The present invention relates generally to the manual lifting and stacking of containers such as drums, barrels, canisters, or the like, particularly in close quarters where room does not permit manipulation by mechanized devices, but where the size and weight density are such that two persons are required to perform the lifting and placement operation and the operation is also logistically difficult, i.e., the two individuals must grapple with each container totally by hand. Problems are especially acute where storage capacity and transportation efficiencies require a plurality of layers of containers to be provided. The present invention provides a manual lifting device of relatively simple construction that is safely and easily operated by two persons. The lifting device has particular application in the manufacture and storage of munition propellant materials which are typically stored in cylindrical fiber drums which may need to be stacked and unstacked several times in close quarters.
II. Related Art
In the past, containers or canisters such as fiber drums containing processed propellant materials have been stored and moved in single-layer fashion manually loaded by two individuals who lift and place them on pallets. The pallets have been addressed by forklifts which stack them for storage or shipment. This method has several drawbacks, however, housing efficiency is reduced due to lost storage space, both on the pallets and in the storage buildings where much additional room has to be provided for the operation of the forklifts. Also, there are reduced efficiencies in the transportation of the materials because trucks transporting the product from the pack-out facilities have been limited to loading a single pallet layer in many cases because of lack of available room at destination buildings. Furthermore, additional manpower and time may be required if it is necessary to transport forklifts back and forth between storage buildings. Moreover, owing to the hazardous nature of the product being moved, the forklifts (or any other mechanized devices) used have to be rated to meet the hazards classification of the storage facility.
Known canister/barrel lifting devices also include manual jacks, hydraulic lifts and electric lifts and, while they can be used, they also introduce the same or similar types of inefficiencies and problems to the operation including space requirements and the need to meet hazardous classification requirements, particularly in the case of powered devices.
There has remained a need to provide a more efficient and user-friendly device to enable a pair of operators to lift and stack canisters or drums of the class in a limited space with a minimum of physical stress.
SUMMARY OF THE INVENTION
The present invention provides a lightweight, efficient and inexpensive two-person manual lifting device for accessing, capturing and lifting shaped containers such as cylindrical propellant drums. The manual lifting device of the invention features a pair of shaped converging/diverging opposed clamp jaw shapes having a width for capturing and releasing a container object of interest to be lifted. The device consists of two clamp halves held together by connecting plate members. Each clamp half includes a jaw shape configured to match and engage the shape of a partial perimeter of a container to be lifted, flanked by a pair of spaced jaw extensions or arm members which lead back from the jaw, are generally parallel and which diverge at an angle from the central jaw shape. The device also includes a pair of spaced generally parallel handle rods, each of which is attached through openings near the ends of the extensions or arms of one clamp jaw shape member. In this manner, a pair of opposed symmetrical clamp halves are assembled. The handle rods extend beyond the arms of the clamp jaw shape members forming handles designed to be grasped and lifted by two persons, one at each end of an assembled unit in the manner of a litter.
The clamp halves are assembled together using a pair of linking plates to connect each of the pairs of jaw extension arms of the two opposed jaw clamp shapes in the manner of an A-frame, spacing the jaw shapes and corresponding handles. The linking or connecting plates are fastened to the arms at two spaced points, an outer location near the free ends of the arms and an inner location near the clamp jaw shapes. At the inner location, the connecting plates are slotted so that the arms and clamp jaw shapes are free to pivot with respect to the connecting links on an amount corresponding to the length and shape of the slots, enabling the opposed clamp jaw shapes to converge and diverge a limited amount in a pivotal fashion about the outer connections.
In operation, the device is normally grasped by opposed facing persons, each grabbing two-end handles and easily slightly rotating the handles to cause the opposed clamp jaw shapes to open to maximum separation. The device can then be lifted over the lid of a container of interest and the handles rotated in the opposite direction to cause the jaw clamps to converge on the body of the container of interest. Once engaged, the weight of the body of the container of interest acts to hold the opposed clamp jaw shapes against the sides of the container and the operators merely need to lift the handles and place the container where desired. The handles can then be rotated in the opposite direction and the device easily removed from the container.
It will be apparent that lifting units of many sizes and shapes can be produced for use in moving containers of a corresponding variety of shapes and sizes. The lifting devices of the invention are preferably made of lightweight material such as aluminum tubing and plate stock. Flat plastic spacer/bushings are provided between the connector plates and the extension arms to preclude metal-on-metal wear. In addition, the inside surface of each facing clamp jaw face is preferably provided with a friction surface such as a layer of ribbed rubber sheet to assist gripping action on the sides of a canister or other container of interest during lifting. Once engaged, of course, the weight of the canister itself generates clamping forces at this stage. Handle grips may be added to the hollow aluminum tubing handles, if desired.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a perspective view of a container lifting unit in accordance with one embodiment of the present invention;
FIG. 2 is a top view of the container lifting device of FIG. 1 ;
FIG. 3 is a side elevational view of the container lifting device of FIG. 2 ;
FIG. 4 is an end elevational view of the container lifting device of FIG. 2 ; and
FIGS. 5 a and 5 b are enlarged top and side views of a connecting link and plastic spacer for the unit of FIGS. 1–4 .
DETAILED DESCRIPTION
The detailed description that follows illustrates a successful embodiment of the inventive concept that is presented by way of example only without any intent to limit the scope of the invention. It is particularly noteworthy that the size, shape and degree of allowable adjustment between open and clamp positions of the lifting unit of the invention can be varied and while the device as shown is particularly well suited to lifting and stacking fiber drums filled with propellant materials, or the like, the device can be adapted in size and shape to provide units to lift containers in a wide variety of sizes and shapes.
FIG. 1 depicts a perspective illustration of one preferred embodiment of a container lifting unit in accordance with the invention which is designed to address cylindrical or drum-shaped containers, possibly propellant-containing drums. The device is designated generally at 10 and can generally be depicted as being two symmetrical opposed half-clamps (or clamp halves) which assembled together form a clamping system to lift the container situated therebetween. The unit includes a pair of arcuate opposed spaced clamp jaw shapes 12 , 14 , each jaw shape having a gripping width and a pair of generally parallel outer extensions or arm members as at 16 , 18 , respectively, which diverge at an angle from the jaw shapes, each of the arm members 16 , 18 being provided with an opening near the free end thereof as at 20 , 22 adapted to receive respective rods or tubes 24 , 26 in fixed relation thereto. The tubes extend outward at both ends from the arm openings to form a pair of handles, one on each end.
A pair of generally triangular-shaped connecting link plate members 28 , 30 are provided to link respective pairs of jaw extension arm members thereby connecting the two halves of the system together, said arcuate clamp jaw shapes 12 , 14 being thereby placed in opposed spaced relation and the handle rods or tubes 24 , 26 generally in parallel spaced relation. Each of the connecting link plates 28 , 30 is connected to each respective corresponding arm member at two spaced locations. Thus, connecting link plate 28 is connected to arm member 16 as at an outer location 32 and at an inner location 34 , preferably using shoulder bolts as shown. Likewise, extension or arm member 18 is fastened to link plate 28 at outer location 36 and inner location 38 in symmetric fashion. In the same manner, connecting link plate 30 is fastened to the remaining arms 16 , 18 at outer locations 40 , 42 and corresponding respective inner locations 44 , 46 using shoulder bolts. Plastic spacer/bushings as at 48 ( FIG. 5 a ) are placed between the arms 16 , 18 and the respective corresponding connecting link 28 , 30 to provide sliding surfaces for the movement of the parts of the unit. These are the same shape as the connecting links and one is shown at 48 in FIG. 5 b.
In addition, the opposed surfaces of clamping jaw shapes 12 , 14 are preferably provided with a friction surface such as being lined with a ribbed rubber sheet as at 50 in FIG. 1 to provide a additional gripping action on the sides of the container during lifting. Also, the handle tubes 24 , 26 are preferably provided with handle grips as at 52 (which may be similar to bicycle handle-bar grips) for ease of use.
As best seen in the enlarged link member drawing of FIG. 5 a, each outer fastening location nearest the free end of each arm is use of a pivot joint which pivots a short distance (using a shoulder bolt as indicated) about which the link plate and the arm member are free to respectively pivot. As particularly illustrated in FIG. 5 a, the openings corresponding to the inner connections for the link plates are in the form of curved slots 54 which enable the limited pivoting action between the connecting plates and the clamp jaw arm members which allows, in turn, limited convergence/divergence between the opposed clamp halves. This enables the clamp jaw to be opened slightly to accommodate lids and containers of slightly varying sizes and then rotate into a clamping position to grip the object to be lifted. It will further be noted that a downward motion or force as would be generated by a grabbed or clamped object also forces the clamp jaws toward the closed or grabbing position so that the weight of the object itself provides the grabbing force during lifting and transport; and when the container is placed in the desired position, the handles can readily be rotated outward to release the clamp and allow the unit to slide back over the top of the container that has been moved. Of course, the slotted openings 54 may be any desired shape or length corresponding to a particular embodiment design.
It will occur to those skilled in the art that clamp jaws can be made any desired shape such as rectangular in addition to arcuate shapes and of any diameter and width to address containers of various sizes and shapes. As one skilled in the art will readily appreciate, the unit requires only a few uncomplicated parts and is readily assembled and therefore inexpensive; and it is very efficient. This allows a variety of sizes of the units to be stocked at relatively little cost.
Materials of construction can be anything suitable, however, lightweight metals such as aluminum or high impact plastics are preferred and the plastic spacer/bushings are preferably polyethylene, Teflon (polytetrafluorsethylene) or the like.
This invention has been described herein in considerable detail in order to comply with the patent statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use such specialized components as are required. However, it is to be understood that the invention can be carried out by specifically different equipment and devices, and that various modifications, both as to the equipment and operating procedures, can be accomplished without departing from the scope of the invention itself. | A low cost manual container lifting and placement unit operable by two people is disclosed which allows clamping, lifting and release of containers in a simple manner. The unit is made in two clamp jaw halves and each is connected to a rod that extends out to form handles on each side. The halves are connected by linking plates which allow rotation between the two halves causing the clamp halves to converge to grip a container of interest and diverge to release the container. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to mechanical equipment generally and, more particularly, to a novel mounting bracket for mounting small compressors to condenser plates, the latter having a variety of bolt patterns.
2. Background Art
While the present invention is described with reference to the mounting of compressors, it will be understood that it is adaptable to any situation in which a variety of mounting configurations must be accommodated.
Small refrigeration units are used, for example, at locations where ice is sold to keep the chests containing the ice below 32 degrees Fahrenheit. Typically, the compressors for such refrigeration units are mounted on the condenser plates of the refrigeration units. The compressors are relatively high maintenance items and must be occasionally replaced. Unfortunately, the bolt patterns on the condenser plates are far from uniform and, if a service organization services a large number of such installations, a large number of different compressors must be inventoried.
For example, a service organization may have to service hundreds of different ice merchandisers having 1/4-, 1/3-, and 1/2-horsepower compressors purchased, say, over the past 25 years from various manufacturers. As a result, the mounting studs that hold the compressors to the rubber mounting spacers to the compressor mounting feet have many different configurations. If the configuration of the mounting studs does not match that of the configuration of the feet on a particular replacement compressor, then the entire condenser plate and assembly have to be removed and drilled to install new mounting studs. This consumes time and increases maintenance costs, as well as increasing the time the refrigeration unit is out of service. Another problem occurs because on some of the units, the old mounting studs are welded to the condenser plates and have to be removed to obtain clearance to mount the new compressors.
One of the three major so called "J style" compressor manufacturers makes all of its replacement compressors with the mounting feet welded to the compressors. This manufacturer make these compressors with three different base configurations and does not supply any adaptors. If the service organization carries the three types of compressors in 1/4-, 1/3-, and 1/2-horsepower sizes, nine different compressors must be inventoried and carried on the service vehicle. Many times, these compressors do not match the configurations previously used by the manufacturer as well as those of other manufacturers. Replacing the compressors becomes a compounded problem.
Another one of the three major "J style" compressor manufacturers also makes all of its replacement compressors with the mounting feet welded to the compressors and it presently makes compressors with five different base configurations; however, this company does supply some single use adapters. If the service organization carries all five types in the above three sizes, as well as adapters therefor, the inventorying problem grows substantially and, even at that, much of the time these do not match the configurations previously used by this manufacturer as well as some currently being used by the other manufacturers.
The other one of the three major "J style" manufacturers makes some if its replacement compressors with the mounting feet welded to the compressors, but they also make replacement compressors without a welded base to accept a bolt-on base. This manufacturer supplies seven difference single use base configuration which are not interchangeable. Again, even if the service organization carries all seven bases, with their 1/4-, 1/3-, and 1/2-horsepower compressors, much of the time these do not match the configurations previously used by this manufacturer as well as some currently being used by the other manufacturers.
There are several independent suppliers of adaptors all of which are either single use or which mount each stud mount independently to the compressor without the security of a solid base. Some are very thin strips with interfitting sliding channels secured with wing nuts under the compressor. These wing nuts sometimes hit the compressor and/or vibrate loose. There are others that are attached directly to the mounting studs without the value of the use of a rubber mounting spacer.
Accordingly, it is a principal object of the present invention to provide a universal mounting bracket and method of use that can be employed to mount compressors to condenser plates when the condenser plates have a wide variety of mounting stud patterns.
It is a further object of the invention to provide such a mounting bracket which is sturdy.
It is an additional object of the invention to provide such bracket and method that are convenient to employ.
It is another object of the invention to provide such bracket that is economically constructed.
Other objects of the present invention, as well as particular features, elements, and advantages thereof, will be elucidated in, or be apparent from, the following description and the accompanying drawing figures.
SUMMARY OF THE INVENTION
The present invention achieves the above objects, among others, by providing, in a preferred embodiment, a universal mounting bracket, comprising: a plate member; means in said plate member to mount said mounting bracket to a first device; and adjustable means in said plate member to mount said mounting bracket to a second device, said second mounting device having any one of a number of mounting patterns.
BRIEF DESCRIPTION OF THE DRAWING
Understanding of the present invention and the various aspects thereof will be facilitated by reference to the accompanying drawing figures, submitted for purposes of illustration only and not intended to define the scope of the invention, on which:
FIG. 1 is perspective view of a compressor attached to a refrigeration unit mounted on an ice container, according to the present invention.
FIGS. 2 and 3 an isometric views showing, in more detail, the means of attachment of the compressor of FIG. 1.
FIGS. 4 and 5 are isometric views of the universal mounting bracket of the present invention.
FIGS. 6A-6C, 7 and 8 are fragmentary views illustrating details of the arrangement of the present invention for attaching the universal mounting bracket to a compressor plate.
FIG. 9 is a perspective view illustrating, in detail, the use of the universal mounting bracket of the present invention.
FIG. 10 illustrates an alternative embodiment of the universal bracket of the present invention.
FIGS. 11-14 illustrate mounting foot extensions for use with the universal mounting bracket, according to the present invention.
FIGS. 15A-15F are top plan views illustrating some of the different mounting configurations that can be accommodated by the universal mounting bracket.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference should now be made to the drawing figures, on which similar or identical elements are given consistent identifying numerals throughout the various figures thereof, and on which parenthetical references to figure numbers direct the reader to the view(s) on which the element(s) being described is (are) best seen, although the element(s) may be seen also on other views.
FIG. 1 illustrates a familiar type of chest 30 which may be located in a merchandising establishment and may contain blocks and/or cubes of ice for sale. Mounted on chest 30 is a refrigeration unit, generally indicated by the reference numeral 32, which is employed to keep the contents of the chest below 32 degrees Fahrenheit.
FIGS. 2 and 3 illustrate more clearly some of the details of refrigeration unit 32. Refrigeration unit 32 includes a control and condenser unit 40 attached to a condenser plate 42. Also attached to condenser plate 42 is a compressor 44, which may be of the type described above, and which has attached to the base thereof a universal mounting bracket 46 constructed according to the present invention. Mounting bracket 46 is configured to be attached to four mounting studs 48 (FIG. 2) which are attached to condenser plate 42, even though the mounting studs may be in any one of a wide variety of patterns. As noted above, absent the use of universal mounting bracket 46, a service organization might have to inventory many different compressors and/or single use adapters.
FIG. 4 illustrates the basic member of universal bracket 46, that being a stamped plate 50 having orthogonally upturned reinforcing flanges 52 formed integrally with the plate. The edges of plate 50 are somewhat V-shaped to provide mechanical clearance required in some installations. A large opening 54 is defined through plate 50 centrally thereof to provide clearance for the bottoms of certain types of compressors. Plate 50 includes four bosses 56 on the upper surface thereof for the bolting of the plate to a compressor. Nearly all of the compressors of the type under consideration have a fairly consistent bolting pattern; however, plate 50 may be arranged to accommodate variations in bolting pattern, as will be described later. Plate 50 also includes four arcuate openings 58 defined therethrough near the corners of the plate and a plurality of slots, as at 60, defined therethrough, the arcuate openings and the slots being employed for the mounting of bracket to condenser plate 42 (FIG. 2) as is described below.
FIG. 5 shows rings 66 die pressed into arcuate openings 58 to provide for one mode of use of mounting bracket 46. FIGS. 6A-C illustrate a ring 66 in three different positions in an opening 58 to accommodate three different positions of a mounting stud 48 (FIG. 2) on condenser plate 42 (neither shown on FIGS. 6A-C). Since three points define an arc, the shape of arcuate opening 58 can be selected to accommodate the three different positions. Of course, ring 66 can accommodate any stud positions in between the three indicated on FIGS. 6A-C. It will be understood that the other rings 66 will be likewise adjusted for the particular stud pattern being accommodated.
With reference to FIG. 7, it can be seen that ring 66 comprises an outwardly open, circular channel member with the sides of the ring being pressed around the upper and lower surfaces of plate 50 to grippingly secure the ring in arcuate opening 58.
FIG. 8 illustrates a rubber mounting spacer 70 grippingly inserted in ring 66 to absorb compressor vibrations in the manner of original compressor installations.
FIG. 9 illustrates, in detail, the mounting of compressor 44 to condenser plate 42 using universal mounting bracket 46. Bracket 46 is first attached to the base of compressor 44 by means of four screws 80 (only three shown on FIG. 9) inserted through bosses 56 into the base of the compressor. Four rubber mounting spacers 70 (only three shown on FIG. 9) are inserted in rings 66 and the rings rotated in arcuate openings 58 to match the pattern of mounting studs 48 on condenser plate 42. Then, mounting bracket 46 with compressor 44 attached thereto is set on condenser plate 42 with mounting studs 48 extending through rings 66 and four pins 88 (only one shown on FIG. 9) inserted through the distal ends of the mounting studs. It will be understood that mounting bracket 46, configured as shown, can be employed to accommodate any stud pattern having spacings fitting within the scope of adjustment of rings 66.
FIG. 10 illustrates another embodiment of the universal mounting bracket of the present invention, generally indicated by the reference numeral 46'. Elements of mounting bracket 46' which are the same as or similar to the elements of mounting bracket 46 (FIG. 5) are given primed reference numerals. Mounting bracket 46' is configured to accommodate different compressor mounting patterns. This is accomplished by providing bosses 56' with oval openings 96 therein to accommodate rectangular mounting patterns or greater or lesser size.
Plate 50 of mounting bracket 46 is sized so that it may be employed with the smallest mounting pattern to be accommodated. However, this means that arcuate openings 58 cannot be solely employed with larger mounting patterns. FIG. 11 illustrates a mounting foot extension, generally indicated by the reference numeral 100, which includes a primary plate portion 102 having an opening 104 defined through the distal end thereof, the opening being sized to receive therein a rubber mounting spacer 70. Mounting foot extension 100 is attached to plate 50, as indicated on FIG. 12, by means of a elevated tab formed at the proximal end of the foot extension, parallel with the primary plate portion, and insertable in a slot 60 in plate 50. A screw 104 extends through a washer 106 on ring 66 and is inserted into a threaded boss 108 which is sized to closely fit into the ring, thus locking mounting foot 100 into plate 50 and providing an extended mounting spacer 70 for the insertion therein of a mounting stud 48 (FIG. 9) as is described above.
FIGS. 13 and 14 illustrate an alternative embodiment of a mounting foot, generally indicated by the reference numeral 100', the elements thereof which are the same as or similar to the elements of mounting foot 100 (FIGS. 11 and 12) being given primed reference numerals. Mounting foot 100' includes a ring shaped flange 120 orthogonal to primary plate 102', with upwardly extending tabs 122. Flange 120 is sized to closely fit in ring 66 with tabs 122 bent over the upper surface of the ring.
FIGS. 15A-15F illustrate some of the mounting patterns that can be accommodated by mounting bracket 46. While the patterns shown are all rectangular, it will be understood that triangular patterns may be accommodated also by suitable selection of the rings 66 (FIG. 9) and/or foot extensions 100 (FIG. 12).
Mounting bracket 100 is sturdy and can be economically constructed from any suitable materials by conventional fabrication methods.
It will thus be seen that the objects set forth above, among those elucidated in, or made apparent from, the preceding description, are efficiently attained and, since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matter contained in the above description or shown on the accompanying drawing figures shall be interpreted as illustrative only and not in a limiting sense.
It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween. | In a preferred embodiment, a universal mounting bracket, comprising: a plate member; means in said plate member to mount said mounting bracket to a first device; and adjustable means in said plate member to mount said mounting bracket to a second device, said second mounting device having any one of a number of mounting patterns. | 5 |
RELATED APPLICATIONS
[0001] The present application claims the benefit under 35 U.S.C. §119(a)-(d) of British Patent
[0002] Application No. 1500650.5 filed Jan. 15, 2015, the disclosure of which is incorporated herein by reference.
TECHNICAL FIELD
[0003] The present invention relates to a joint-orientation monitoring system for the creation of patient kinematic range data, particularly, but not necessarily exclusively, for the selection of a surgical procedure. The invention also relates to a method of pre-operatively determining the suitability of a joint for said surgical procedure.
BACKGROUND
[0004] Old age, wear, and disease all contribute to the deterioration of skeletal joints. As the average age of the general population grows, it is becoming ever more necessary to perform surgery on various joints, such as the hip joint or knee joint, for either maintenance or replacement purposes.
[0005] Such surgery can be very invasive, and thus traumatic for the patient. For instance, in order to perform a hip arthroplasty, it is necessary to create a large incision in the patient and then forcibly dislocate the femur from the acetabulum. The use of such a drastic procedure is therefore carefully limited to only those who will benefit to the greatest extent.
[0006] Given the limited biomedical lifespan of artificial implants, multiple surgical procedures may be required to maintain operable functionality of the joint, especially in view of the increased longevity of humans. The longevity of these replacement joints is further limited, in some cases, by the particular anomalies and anatomical quirks of the patient.
[0007] Design and implantation of artificial joints in the past has had to be based upon a generic patient biometry, in order to be focussed on providing the greatest benefit to the greatest number of people. As technology has progressed, it has become possible to make tailored artificial joints that are bespoke to each individual patient, and this has led to increased life-span of joint replacements and a higher overall success rate.
[0008] However, the method of surgical implantation has remained generic in comparison. It is commonplace for patients to be submitted for medical imaging to determine the anatomy of the patient's joint and then to fit the artificial joint in the position deemed most suitable based on this information. Whilst this is acceptable for many patients, it does not result in high success rates in others.
[0009] There are many possible reasons why generic surgery is not suitable in all situations, but one example is that the anatomy of patients' joints responds to movement in different ways. Taking the hip joint as an example, whilst standing still the front of the pelvis may drop slightly and the back rise in what is known as an anterior pelvic tilt. Similarly, whilst seated the reverse may be true and the pelvis may have a posterior pelvic tilt. It is equally plausible that during some activities the pelvis may be tilted laterally.
[0010] The existence and degree of pelvic tilt during static and dynamic activities may vary between patients, which leads to replacement joints wearing at different speeds and in contrasting places, as forces are transmitted through various portions of the joint. This can lead to failures as, for instance, the side of the acetabular cup portion of the replacement hip joint is forced to bear more load than it is designed for, due to abnormal pelvic tilt.
[0011] Recent developments in the field have led to the creation of techniques which consist of extensive pre-operative investigation of the patient in order to provide a more bespoke surgical method. These methods allow a much more tailored approach to the surgery, whereby the particular anatomical differences between patients are taken into account before deciding on specific alterations to the generic surgical technique. For instance, the acetabular cup of a total hip replacement may be placed at a slightly different angle from normal in order to compensate for a particular patient's pelvic tilt. Alternatively, the replacement knee joint could be altered in its position in a particular way to allow a patient to walk with their normal gait.
[0012] These new techniques result in a greater success rate of joint replacement surgeries, but they may take longer or cost a greater amount due to the time necessary to obtain and process the pre-operative information. As such, it is not economically viable to provide all patients with these bespoke techniques. For some patients, the generic surgery is perfectly adequate and causes no problems with the longevity of the joint.
SUMMARY
[0013] It is an object of the present invention to create a method of pre-operatively determining the suitability of a patient's joint for a particular surgical procedure. By examining the patient beforehand, it is possible to distinguish between patients able to be successfully treated using generic surgical techniques and those who require more bespoke surgery. A further object of the invention is to provide a device for successfully determining this suitability.
[0014] According to a first aspect of the invention there is provided a joint-orientation monitoring system, preferably for the creation of patient kinematic range data of a joint of a patient, the joint-orientation monitoring system comprising: a joint-orientation monitoring device which determines joint orientation data; and a processor in communication with the joint-orientation monitoring device; the processor determining patient kinematic range data from joint orientation data received from the joint orientation monitoring device.
[0015] Patient kinematic range data is useful as it enables joints of patients to be compared to one another and also to standardised average values. This enables simplified monitoring of the anatomy of patients to allow better decision making about surgical procedures.
[0016] Preferably, the joint-orientation monitoring system may further comprise a memory element which stores patient kinematic range data and/or preferred kinematic range data.
[0017] Additionally, the joint-orientation monitoring system may include a logic element which compares the patient kinematic range data and the preferred kinematic range data.
[0018] Comparing the two sets of data allows the difference between the patient kinematic data and the preferred kinematic data to be determined, thus allowing specific decisions about a surgical procedure to be undertaken to be made.
[0019] In a preferable arrangement, at least the processor and/or logic element may be parts of a computing device.
[0020] Utilising such an arrangement allows commonly available computing devices such as personal computers, tablet computers, or smart phones to be used, lowering the up-front cost of procuring the system.
[0021] Optionally, the joint-orientation monitoring device may comprise a wearable portion.
[0022] The wearable portion can allow parts of the system to be placed on or close to the patient's body, increasing the accuracy of any measurements taken of the joint.
[0023] It may be advantageous for the joint-orientation monitoring device to include a plurality of accelerometers which senses joint motion.
[0024] Accelerometers are a relatively cost-effective and simple way of measuring acceleration, but the information harvested by them may be relatively easily translated by a computer into velocity and position information. Therefore, use of accelerometers can provide rapid and accurate positional information to the system of many different points on the body.
[0025] It may also be advantageous for the joint-orientation monitoring device to include a video capture device which tracks joint orientation.
[0026] Use of a video capture device optionally allows the joint orientation and/or motion of a patient to be recorded without needing to use devices in physical contact with the patient. Avoiding physical contact with the patient ensures that the joint-orientation monitoring device does not hinder the natural movements of the patient, restricting the accuracy of the joint-orientation data. Video capture devices also allow the information to be captured easily and automatically whilst a patient is within the viewable range.
[0027] In a preferable arrangement, the video capture device may include depth-sensing means.
[0028] Use of depth-sensing means, which allow the video capture device to capture three-dimensional information, allows additional information to be obtained by the video capture device, which improves the accuracy of the overall data gathered.
[0029] Optionally, the joint-orientation monitoring device may further include a plurality of markers, trackable by the video capture device, which enhances tracking of joint orientation.
[0030] Markers enable the video capture device to more accurately evaluate the relative positions of the patient's anatomy, thus providing more useful information.
[0031] It may be advantageous for the joint-orientation monitoring system to further comprise a wireless communication means for wirelessly transferring data between the joint orientation monitoring device and the processor.
[0032] By doing so, there is no need for cabling to be provided connecting each component or device. This is especially beneficial when a wearable device is utilised, as it prevents any undesirable limitation of the patient's motion.
[0033] According to a second aspect of the invention there is provided a method of pre-operatively determining surgical suitability of a joint, preferably for a surgical corrective procedure, preferably using a joint-orientation monitoring system in accordance with the first aspect of the invention, the method comprising the steps of: a] determining a patient's joint orientation in a plurality of situations; b] determining a patient kinematic range of the patient joint based on the said joint orientations; c] comparing the determined patient kinematic range to a preferred kinematic range; and d] determining that the joint can accept a first surgical corrective procedure if the patient kinematic range falls within the allowable kinematic range, else determining that the joint can accept a second surgical corrective procedure which is different from the said first surgical corrective procedure.
[0034] Determining the suitability of a particular patient to receive a specific surgical corrective procedure prevents unnecessary costs being incurred by use of more expensive or time-consuming techniques and procedures where they are not specifically needed.
[0035] Beneficially, the patient's joint orientation may be at least partially determined by way of at least one medical imaging technique. These techniques may include at least one of X-ray imaging, computed tomography, or magnetic resonance imaging.
[0036] Medical imaging techniques allow joint orientation information to be measured which is not attainable by way of solely external methods or imaging.
[0037] In a preferable embodiment, the orientation of the patient's joint may be at least partially determined by way of motion tracking techniques.
[0038] Use of motion tracking techniques enables joint orientation information to be obtained without resorting to expensive medical imaging. It also allows patient joint orientation to be viewed in dynamic situations if video, rather than still, imaging is used.
[0039] Beneficially, the patient kinematic range is indicative of a range of motion of the patient's joint. Additionally, the preferred kinematic range is indicative of the allowable range of joint motion to qualify for a predetermined surgical corrective procedure.
[0040] Typically, the first surgical corrective procedure may be a standard surgical corrective procedure and the second surgical corrective procedure may be an enhanced surgical corrective procedure.
[0041] In a preferred embodiment, the first and/or second surgical corrective procedure may be a joint arthroplasty. Whilst other types of surgery may also be suitable, the method is most well suited to joint surgery, including, but not limited to, reconstruction and replacement surgeries.
[0042] According to a third aspect of the invention, there is provided a method of pre-operatively determining a surgical suitability of a joint for either a generalised surgical corrective procedure or a bespoke surgical corrective procedure, the method comprising the steps of: a] using a joint-orientation monitoring device, determining patient joint orientation data for a plurality of different kinematic joint positions which are characteristic of activities performed by the patient's joint; b] transmitting the said joint orientation data to a processor; c] computationally determining a patient kinematic range of the patient joint based on the joint orientation data; d] comparing the determined patient kinematic range to a pre-determined preferred kinematic range which is indicative of suitability of the patient joint for the generalised surgical corrective procedure; and e] determining that the joint is suitable for the generalised surgical corrective procedure if the patient kinematic range falls within the preferred kinematic range, else determining that the joint is suitable for the bespoke surgical corrective procedure which is different from the said first surgical corrective procedure.
[0043] The invention will now be more particularly described, by way of example only, with reference to the accompanying drawings.
BRIEF DESCRIPTION OF FIGURES
[0044] FIG. 1 shows two pictorial representations of a person, depicting an example of anterior/posterior pelvic tilt during standing and sitting;
[0045] FIG. 2 is a flow diagram of a method of pre-operatively determining the suitability of a joint for a surgical corrective procedure, in accordance with the second aspect of the invention.
[0046] FIG. 3 is a pictorial representation of a first embodiment of a joint-orientation monitoring system in accordance with the first aspect of the invention;
[0047] FIG. 4 is a pictorial representation of a second embodiment of a joint-orientation monitoring system in accordance with the first aspect of the invention;
[0048] FIG. 5 is a pictorial representation of a third embodiment of a joint-orientation monitoring system in accordance with the first aspect of the invention; and
DETAILED DESCRIPTION
[0049] Referring firstly to FIG. 1 of the drawings, there is shown a depiction of a patient 10 a , 10 b in both standing and seated positions, showing a representation of the pelvic tilt in each. As can be seen from the standing FIG. 10 a , the pelvis 12 a, in this example, is aligned vertically, indicated by a dotted line A, with no or substantially no anterior or posterior tilt. Conversely, in the seated FIG. 10 b , the pelvis 12 b presents a posterior pelvic tilt 14 of a degrees. It can be appreciated that this pelvic tilt 14 will result in a different angular position of the femur, which is not shown, relative to the acetabulum 16 a, 16 b.
[0050] This tilt 14 , and the resultant relative positioning of the first and second portions of the joint, which in this case are the acetabulum and femur, can be measured in various positions, which are not limited to those depicted in FIG. 1 . This relative positioning is hereafter referred to as ‘joint orientation’.
[0051] Joint orientation can clearly be exhibited in not only anterior and posterior directions, as shown, but also laterally. The resultant pluralities of joint orientations in three dimensions can be represented by values known as a patient kinematic range, which is preferably indicative of the entire range of the possible joint orientations for a particular joint. For instance, the patient kinematic range could describe the entire range of motion of the femoral head with respect to the acetabular cup. This could be as simple as the maximum angles of motion in posterior/anterior and lateral directions, or as complex as a fully three-dimension map of the movement of the separate parts of the joint.
[0052] A patient kinematic range for each joint can be utilised in decision-making processes about the treatment plan for each particular joint, as shown in FIG. 2 . Measurements of the patient's joint orientation 18 in step S 1000 for a particular joint can be converted into a patient kinematic range 20 in step S 1100 .
[0053] The patient kinematic range 20 is specific to each joint of a patient and can impact highly on the success-rate of any particular surgical corrective procedure. Where the patient kinematic range 20 of a joint of a patient is outside of the general range of the population at large, complications can ensue after surgery, as the surgery may be tailored to be most suitable for joints with the kinematic range of the average person, hereafter referred to as a ‘preferred kinematic range’, referenced as 22 and determined at step S 1200 .
[0054] The preferred kinematic range 22 can be produced by comparing the joint orientations of a large number of people to produce an average, preferably modal, range, which is used to create a particular surgical corrective procedure. This information may be procured from patient library data, formed through studies of anatomy. Alternatively, the preferred kinematic range may be determined in a retrospective manner, by studying the method of a surgical corrective procedure to ascertain the joint orientations for which it is most suitably used. Other methods of determining the preferred kinematic range 22 will be obvious to those skilled in the art.
[0055] By comparing the patient kinematic range 20 to the preferred kinematic range 22 at step S 1300 , the suitability of a joint for a particular surgical procedure can be determined. In the present embodiment of the method, if the patient kinematic range is found to be within the preferred kinematic range at step S 1400 , the patient can be recommended for a first surgical corrective procedure 24 at step S 1500 . The first surgical corrective procedure 24 will preferably be that which is created to be suitable for the general population, with only the usual level of adjustment available.
[0056] Conversely, if the patient kinematic range 20 is found to be outside of the preferred kinematic range 22 , the patient may be recommended for a second surgical corrective procedure 26 at step S 1600 . This second surgical corrective procedure 26 is preferably a bespoke surgery which is capable of sufficiently compensating for the particular anatomy of the patient to provide a higher success-rate than the first surgical corrective procedure 24 .
[0057] Commonly, whilst generally being an enhanced surgical corrective procedure, the second surgical corrective procedure 26 may be more expensive, time-consuming, or otherwise complicated procedure than the first surgical corrective procedure. As such, it is preferable to utilise the first surgical corrective procedure 24 when a case allows. Therefore, the prescribed method enables the allowability of a particular surgical corrective procedure to be calculated and measured, enabling a surgeon or other decision-maker to provide the best care, when success, cost, and other variables are taken into account.
[0058] Whilst the preferred embodiment allows for decisions to be made between two different surgical corrective procedures, it is also foreseeable that the method could be utilised to distinguish a correct or preferred course of action between three or more surgical corrective procedures. For example, a third surgical corrective procedure may be preferable for a joint with a patient kinematic range below the preferred patient kinematic range, or a fourth surgical corrective procedure may be suitable for a joint with a patient kinematic range more than 50% greater than the preferred kinematic range. The list of possibilities hereby disclosed is not intended to be exhaustive and a greater number of iterations of the method of the present invention will be obvious to those skilled in the art.
[0059] Three embodiments of a system for the creation of patient kinematic range data are depicted in FIGS. 3 to 5 . The embodiment of FIG. 3 , indicated globally at 100 , comprises a joint-orientation monitoring device 102 and a personal computer 104 , having at least a processor 106 .
[0060] The joint-orientation monitoring device 102 may typically include a wearable device 108 worn by a patient 110 , which in this embodiment is a pelvic garment 112 , embedded with a plurality of sensors 114 . The sensors are more particularly accelerometers 116 , which are therefore suited to detecting acceleration of a number of different points on the pelvic garment 112 and therefore pelvis and femur. As the pelvic garment 112 is preferably tight-fitting or snug, the accelerometers 116 each detect the acceleration of a point on the patient's body 110 , which is hereby referred to as ‘joint orientation data’.
[0061] Evidently, a pelvic garment 112 is suitable for the detection of the pelvic orientation, and similar joint-orientation monitoring devices can be imagined for other joints.
[0062] The joint orientation data is relayed from the pelvic garment 112 to the computer 104 via, preferably wireless, communication means 118 . This wireless communication means 118 comprises a first transponder unit 120 a on the pelvic garment 112 and a second transponder unit 120 b in communication with the computer 104 .
[0063] The first and second transponder units 120 a, 120 b communicate via radio waves in this embodiment, but it is equally plausible that they may instead communicate by microwaves, infrared radiation, Bluetooth®, or any other wireless communication method or suitable data transmission protocol. It would also be possible for the pelvic garment 112 and computer 104 to be interconnected in a wired fashion, but this may be disadvantageous due to the dangers of trailing wires and the undesired tethering of the patient 110 , which could affect joint orientation data.
[0064] The received joint-orientation data is processed by the processor 106 , housed within the computer 104 . Joint-orientation data, which in this case is received as recorded acceleration data, can be translated by the processor 106 to indicate the relative positions of each data-providing accelerometer 116 and therefore the related accelerations of various pelvic positions. As such, patient kinematic range data can be produced, which in this case is indicative of the joint orientation of the patient's hip joints.
[0065] The computer 104 further includes a memory element 122 , in this case for example a USB flash drive 124 , upon which is stored preferred kinematic range data. A logic element 126 , used to compare the preferred kinematic range data with the patient kinematic range data, is included within the computer 104 , and in this case is contained within the processor 106 . The joint-orientation monitoring system can therefore also determine the relationship between the patient kinematic range data and the preferred kinematic range data, which can then be displayed on a monitor 128 of the computer 104 , if required.
[0066] Whilst shown as a USB flash drive 124 , the memory element 122 may additionally or alternatively be provided by way of a hard disk drive, solid state drive, or other memory type. Similarly, data output, which is provided by the monitor 128 , may additionally or alternatively be provided by other data output means, such as a speaker or printer, or transmitted electronically, either in a wired or wireless manner.
[0067] FIG. 4 depicts a second embodiment of a joint-orientation monitoring system. Similar or identical features have been omitted from further description, for brevity.
[0068] The joint-orientation monitoring device 202 of the second embodiment, indicated globally as 200 , is a video capture device 230 , connected to the computer 104 via a wired communication means 218 . The patient 210 of this embodiment is in a seated position on a chair 232 , and the video capture device 230 is able to determine visually the orientation of the patient's joints. Enhanced joint orientation data can be captured through the use of depth-sensing means 234 , which are also provided by the video capture device 230 . Depth-sensing means 234 are provided by embedded infrared emission and detection within the video capture device 230 .
[0069] The video capture device 230 is therefore able to track the motions and positions of any joints of the patient 210 , as long as the patient 210 is within a viewable field of the video capture device 230 . Advantages of the use of the video capture device 230 include that the patient 210 may not be required to wear restricting devices such as the pelvic garment 112 of the first embodiment 100 . However, the wearing of such tight garments may advantageously allow the video capture device 230 to make more accurate determinations of joint orientation data.
[0070] The processor 106 is able to manipulate the joint orientation data, received from the video capture device 230 as image and depth data, and translate this into the required patient kinematic range data. The video capture device 230 , whilst described as being capable of capturing joint motion, may also be capable of taking still images, with or without integrated depth data, which can also be used to determine the patient kinematic range data.
[0071] A video capture device 230 may be used in conjunction with a pelvic garment similar to that of the first embodiment 100 in order to provide a different manner of joint-orientation detection. For instance, by replacing the accelerometers 116 of the first embodiment 100 with a plurality of markers, for example infrared-reflective markers, a video capture device 230 may be used in place of the accelerometers 116 for detection of the relative positions of the markers. This technique is used in the film industry for motion-capture of the human body, and therefore similar joint-orientation monitoring devices may be incorporated into the joint-orientation monitoring system of the present invention.
[0072] A third embodiment of the joint-orientation monitoring system, depicted in FIG. 5 and indicated globally as 300 , utilises a computer 304 which is remote from the joint-orientation monitoring device 302 . This allows the computer 304 to be operated by an individual remote to a patient 310 , which may be advantageous. Again, similar references refer to parts which are similar or identical to those of the preceding embodiments, and further detailed description is therefore omitted.
[0073] The joint-orientation monitoring system 300 of the third embodiment is limited to the taking of still images, due to the use of an X-ray scanner 336 as the joint-orientation monitoring device 302 . However, by the use of the X-ray scanner 336 , the joint-orientation monitoring system 300 may provide more accurate joint orientation data to the computer 304 as the joint itself can be directly imaged. This may be particularly useful in cases where the patient 310 is particularly overweight or obese, where the joints may be hidden beneath a thick layer of adipose tissue. This layer could cloak the joints from other types of joint-orientation monitoring device, making the system less useful.
[0074] The more accurate joint-orientation data may be utilised to provide more accurate patient kinematic range data, which can therefore be more useful in a decision-making process.
[0075] Whilst an X-ray scanner 336 has been utilised in this embodiment, other medical imaging techniques may be utilised, dependent on choice. For instance, computed tomography can be used to generate 3D models of patient joint anatomy, which can again enhance the accuracy of the patient kinematic range data, or alternatively a magnetic resonance imaging system may be used, if X-rays are not desirable for reasons such as excessive exposure to radiation.
[0076] The joint-orientation monitoring system 100 ; 200 ; 300 should be used to monitor a plurality of different joint positions or motions in order to provide the patient kinematic range data which is most characteristic of the patient's joint. These positions are dependent on the joint for which the patient kinematic range data is being determined. For instance, if a hip joint is being analysed, it may be preferable to view the patient whilst sitting, standing, performing squats, running, and/or other activities which provide a good range of pelvic movement. Similarly, if a knee is to be analysed, similar activities may be analysed. However, if a shoulder is being analysed, it may be more useful to view throwing, arm, swinging, and/or elevation of the shoulder joint. Particular activities will be obvious to the skilled person which are particularly useful for whichever joint is being analysed.
[0077] Additionally, whilst the embodiments depicted in FIGS. 3 to 5 show joint-orientation monitoring systems monitoring the orientation of the patient's hip joint, the systems are equally well suited to monitoring of the knee, shoulder, ankle, or any other anatomical joint. The systems depicted, or further embodiments of such systems, may be used individually or may preferably be used in tandem with one another, such that the most complete joint-orientation data may be provided and therefore the most accurate patient kinematic data may be determined.
[0078] It is therefore possible to provide a joint-orientation monitoring system, for creation of patient kinematic range data from a plurality of joint orientations, along with a method for comparing this patient kinematic range data to preferred kinematic range data in order that an educated decision can be made between first and second surgical corrective procedures. The device and method allow enhanced decision-making to be performed, ensuring the patient is submitted for the most optimal surgical corrective procedure.
[0079] The words ‘comprises/comprising’ and the words ‘having/including’ when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps or components, but do not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.
[0080] It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.
[0081] The embodiments described above are provided by way of examples only, and various other modifications will be apparent to persons skilled in the field without departing from the scope of the invention herein described and defined. | A method of pre-operatively determining the suitability of a joint for a surgical corrective procedure, the method comprising the steps of: determining a patient's joint orientation in a plurality of situations; determining a patient kinematic range of the patient joint based on the said joint orientations; comparing the determined patient kinematic range to a preferred kinematic range; and determining that the joint is suitable for a first surgical corrective procedure if the patient kinematic range falls within the preferred kinematic range, else determining that the joint is suitable for a second surgical corrective procedure which is different from the said first surgical corrective procedure. A device for the determination of the patient kinematic range is also provided. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
The present disclosure relates to subject matter contained in Japanese Patent Application No. 2005-242485 filed on Aug. 24, 2005, the disclosure of which is expressly incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an optical modulator having intensity balance function, and the like. In particular, the present invention relates to an optical modulator and the like which is capable of adjusting optical intensity of optical signals which contains non-desired components so that the intensity of the components become at a similar level, whereby the optical modulator is capable of effectively suppressing the non-desired components when the optical signals are combined.
2. Description of the Related Art
In optical communication, light must be modulated to have signals. As optical modulation, direct modulation and external modulation are known. The direct modulation is one modulating a driving power of semiconductor laser. And the external modulation is one modulating light from semiconductor laser by means other than light source. A modulator used in direct modulation is generally called an optical modulator. The optical modulator modulates optical intensity, phase, etc. by causing physical changes in the optical modulator based on signals. As technical problems of the optical modulator, there exist reduction of driving voltage, realization of a higher extinction ratio for improving modulation efficiency, widening a bandwidth, and improvement of high light utilization efficiency for speeding up and loss reduction of a modulation. In other words, development of a modulator having high extinction ratio is desired. It is to be noted that the extinction ratio is a ratio of optical intensity between the highest level to the lowest level.
As a modulator which shifts frequency of an optical signal to output the optical signal, there is an optical signal side-band (optical SSB) modulator [Tetsuya Kawanishi and Masayuki Izutsu, “Optical frequency shifter using optical SSB modulator”, TECHNICAL REPORT OF IEICE, OCS2002-49, PS2002-33, OFT2002-30 (2002-08)].
An optical FSK modulator which is a modification of an optical SSB modulator is also known [Tetsuya Kawanishi and Masayuki Izutsu, “Optical FSK modulator using an integrated light wave circuit consisting of four optical phase modulator”, CPT 2004G-2, Tokyo, Japan, 14-16 Jan. 2004] [Tetsuya Kawanishi, et al. “Analysis and application of FSK/IM simultaneous modulation” Tech. Rep. of IEICE. EMD 2004-47, CPM 2004-73, OPE 2004-130, LQE 2004-45 (2004-08), pp. 41-46].
FIG. 9 is a schematic diagram showing a basic arrangement of a conventional optical modulation system acting as an optical SSB modulator or an optical FSK modulator. As shown in FIG. 9 , this optical modulation system comprises a first sub Mach-Zehnder waveguide (MZ A ) ( 2 ), a second sub Mach-Zehnder waveguide (MZ B ) ( 3 ), a main Mach-Zehnder waveguide (MZ C ) ( 8 ), a first electrode (RF A electrode) ( 9 ), a second electrode (RF B electrode) ( 10 ), and a modulation electrode.
The main Mach-Zehnder waveguide (MZ C ) ( 8 ) includes an input part ( 4 ) of an optical signal, a branching part ( 5 ) where the optical signal is branched to the first sub Mach-Zehnder waveguide (MZ A ) and the second sub Mach-Zehnder waveguide (MZ B ), the first sub Mach-Zehnder waveguide (MZ A ), the second sub Mach-Zehnder waveguide (MZ B ), a combining part ( 6 ) combining the optical signals outputted from the first sub Mach-Zehnder waveguide (MZ A ) and the second sub Mach-Zehnder waveguide (MZ B ), an output part ( 7 ) outpuffing the optical signal combined at the combining part.
The first electrode (RF A electrode) ( 9 ) inputs radio frequency (RF) signals to two arms composing the first sub Mach-Zehnder waveguide (MZ A ).
The second electrode (RF B electrode) ( 10 ) inputs radio frequency (RF) signals to two arms composing the second sub Mach-Zehnder waveguide (MZ B ).
The modulation electrode is provided on the main Mach-Zehnder waveguide.
Changing USB and LSB, which can be used as information, are attained by means of electrode of the main Mach-Zehnder waveguide; thereby frequency shift keying is realized.
As an optical modulator, an optical double side-band suppressed carrier (DSB-SC) modulator is publicly known. The above described optical modulation system also acts as a DSB-SC modulator. The DSB-SC modulator ideally outputs two side bands, suppressing carrier components. However, in reality, in an output of a DSB-SC modulator shown in the figure below, unsuppressed carrier component (f 0 ) and a high order component (e.g. a second order component (f 0 ±2f m )) remain, preventing extinction ratio from improving.
As a DSB-SC modulator, for example, a DSB-SC modulator having a Mach-Zehnder, PMs provided on both arms of the Mach-Zehnder and a fixed phase shifter provided on one arm of the Mach-Zehnder is disclosed in FIG. 37 of Japanese Unexamined Patent Application Publication No. 2004-252386. FIG. 10 shows an optical modulator described in FIG. 37 of Japanese Unexamined Patent Application Publication No. 2004-252386. An optical DSB-SC modulator ideally outputs two sideband (double sideband) signals, thereby suppressing carrier signal components. However, in the actual output of an optical DSB-SC modulator, other than side band signals, there remain unsuppressed carrier components and high order component signals, preventing extinction ratio from improving. Therefore, traditional optical DSB-SC modulator was aimed to output an optical signal with suppressed carrier component and suppressed high order components.
One of the reasons that there remain a carrier component (f 0 ) and a high order component (e.g. a second order component (f 0 ±2f m ) which cannot be suppressed completely is considered to be as follows. Outputs from each sub Mach-Zehnder waveguide are combined, but intensity of a carrier component (f 0 ) and a high order component (e.g. a second order component (f 0 ±2f m ) of an output signal from one sub Mach-Zehnder waveguide is not always equal to intensity of corresponding components of an output signal from another corresponding sub Mach-Zehnder waveguide. Therefore, the components remain without being suppressed sufficiently when the outputs are combined.
It is an object of the present invention to provide an optical modulator which is capable of adjusting optical intensity of optical signals which contains non-desired components so that the intensity of the components become at a similar level, whereby the optical modulator is capable of effectively suppressing the non-desired components when the optical signals are combined.
SUMMARY OF THE INVENTION
The present invention is basically based on the following idea. The optical modulator includes an intensity modulator ( 12 ) arranged in a waveguide portion between a combining part of a first sub Mach-Zehnder waveguide (MZ A ) and a combining part ( 6 ) of the main Mach-Zehnder waveguide (MZ C ). The intensity modulator modulates intensity of an optical signal propagating through the waveguide portion. Signal intensity of components to be suppressed (e.g., a carrier component (f 0 ) and a high order component (such as a second order component (f 0 ±2f m )) of output signals from the respective sub Mach-Zehnder waveguide are adjusted to be the same level. Then, it is possible to effectively suppress the components to be suppressed (since phase is reversed) when the optical signals from the respective sub Mach-Zehnder waveguide are combined at the combining part ( 6 ).
The optical modulator according to the first aspect of the present invention comprises a first sub Mach-Zehnder waveguide (MZ A ) ( 2 ), a second sub Mach-Zehnder waveguide (MZ B ) ( 3 ), a main Mach-Zehnder waveguide (MZ C ) ( 8 ), a first electrode (RF A electrode) ( 9 ), a second electrode (RF B electrode) ( 10 ), a main Mach-Zehnder electrode (electrode C) ( 11 ), and an intensity modulator ( 12 ).
The main Mach-Zehnder waveguide (MZ C ) ( 8 ) includes an input part ( 4 ) of an optical signal, a branching part ( 5 ) where the optical signal is branched to the first sub Mach-Zehnder waveguide (MZ A ) and the second sub Mach-Zehnder waveguide (MZ B ), the first sub Mach-Zehnder waveguide (MZ A ), the second sub Mach-Zehnder waveguide (MZ B ), a combining part ( 6 ) combining the optical signals outputted from the first sub Mach-Zehnder waveguide (MZ A ) and the second sub Mach-Zehnder waveguide (MZ B ), an output part ( 7 ) outputting the optical signal combined in the combining part.
The first electrode (RF A electrode) ( 9 ) inputs radio frequency (RF) signals to two arms composing the first sub Mach-Zehnder waveguide (MZ A ).
The second electrode (RF B electrode) ( 10 ) inputs radio frequency (RF) signals to two arms composing the second sub Mach-Zehnder waveguide (MZ B ).
The main Mach-Zehnder electrode (electrode C) ( 11 ) applies voltage to the main Mach-Zehnder waveguide (MZ C ) so that a phase difference between an output signal from the first sub Mach-Zehnder waveguide (MZ A ) and an output signal from the second sub Mach-Zehnder waveguide (MZ B ) is controlled.
The intensity modulator ( 12 ) is provided on a waveguide portion between a combining part of the first sub Mach-Zehnder waveguide (MZ A ) and the combining part ( 6 ) of the main Mach-Zehnder waveguide (MZ C ) wherein the intensity modulator modulates intensity of the optical signal propagating through the waveguide portion.
The above arrangement of the present invention adjusts intensity levels of components to be suppressed (a carrier component (f 0 ) and a high order component (e.g. a second order component (f 0 ±2f m )) of output signals from each sub Mach-Zehnder waveguide to be about the same level. This enables to effectively suppress components to be suppressed when optical signals from each sub Mach-Zehnder are combined at the combining part.
Also, a preferable embodiment of the above optical modulator further comprises an asymmetric directional coupler provided at the branching part ( 5 ) of the main Mach-Zehnder waveguide (MZ C ) ( 8 ) wherein the asymmetric directional coupler controls intensity of an optical signal branched to the first sub Mach-Zehnder waveguide (MZ A ) so that the intensity of the an optical signal branched to the first sub Mach-Zehnder waveguide (MZ A ) is higher than intensity of optical signals branched to the second sub Mach-Zehnder waveguide (MZ B ).
If the intensity difference between components to be suppressed is small, the intensity modulator ( 12 ) is required to lessen the intensity of one of the component minutely. Further if optical intensity of an optical signal from the MZ A is weaker than that from MZ B , components to be suppressed cannot be effectively suppressed by the intensity modulator ( 12 ). On the contrary, the optical modulator described above can effectively use the intensity modulator ( 12 ), because the intensity of an optical signal heading toward the MZ A which has the intensity modulator can be higher than the intensity of an optical signal heading toward the MZ B .
It is to be noted that an optical modulator further comprising the intensity modulator ( 12 ) provided on between the output part of the MZ B and the combining part ( 6 ) is the other embodiment of the present invention. In this case, components desired to be suppressed can be adjusted and suppressed, regardless of which intensity is stronger between the optical signals from the MZ A and the optical signal from the MZ B . However, this optical modulator has more complex arrangement than the one above described which has an asymmetric directional coupler.
A preferable embodiment of the above described optical modulator further comprises an intensity modulator ( 13 ) provided on one of two arms composing the first sub Mach-Zehnder waveguide (MZ A ) or one of two arms composing the second sub Mach-Zehnder waveguide (MZ B ) or two or more of the waveguides wherein the intensity modulator ( 13 ) modulates intensity of the optical signals propagating through the waveguides.
Also, a preferable embodiment of the above described optical modulator comprises a Mach-Zehnder electrode (electrode C) ( 11 ) and the electrode C comprises a first main Mach-Zehnder electrode (MZ CA electrode) ( 14 ) and a second main Mach-Zehnder electrode (MZ CB electrode) ( 15 ). The first main Mach-Zehnder electrode (MZ CA electrode) ( 14 ) is laid along at least a part of the waveguide between an output part of the first sub Mach-Zehnder waveguide (MZ A ) and the combining part. The second main Mach-Zehnder electrode (MZ CB electrode) ( 15 ) is laid along at least a part of the waveguide between an output part of the second sub Mach-Zehnder waveguide (MZ B ) and the combining part.
The optical modulator according to the above embodiment is provided with the first main Mach-Zehnder electrode (MZ CA electrode) ( 14 ) and the second main Mach-Zehnder electrode (MZ CB electrode) ( 15 ). This configuration enables the optical modulator to control optical phase of an output signal from the each sub Mach-Zehnder waveguide, thereby suppressing carrier waves (carrier signals) or a high order component (e.g. a second order component (f 0 ±2f m ) of optical signals to be combined.
Also, a preferable embodiment of the above described optical modulator further comprises a control part for controlling a signal source wherein the signal source applies a signal to the first electrode (RF A electrode) ( 9 ), the second electrode (RF B electrode) ( 10 ), and the main Mach-Zehnder electrode (electrode C) ( 11 ).
The control part makes the signal source to (i) adjusting bias voltage applied to the main Mach-Zehnder waveguide (MZ C ) and bias voltage applied to the first sub Mach-Zehnder waveguide (MZ A ) and the second sub Mach-Zehnder waveguide (MZ B ) so that an output from the main Mach-Zehnder waveguide (MZ C ) is increased, (ii) adjusting bias voltage applied to the main Mach-Zehnder waveguide (MZ C ) so that an output from the main Mach-Zehnder waveguide (MZ C ) is decreased, (iii) decreasing bias voltage applied to the first sub Mach-Zehnder waveguide (MZ A ) or the second sub Mach-Zehnder waveguide (MZ B ) so that an output from the main Mach-Zehnder waveguide (MZ C ) is decreased, and (iv) adjusting bias voltage applied to the main Mach-Zehnder waveguide (MZ C ) so that an output from the main Mach-Zehnder waveguide (MZ C ) is decreased.
By using the optical modulator of this embodiment, it is possible to adjust bias voltage applied to each electrode adequately, thereby suppressing a carrier component (f 0 ) and a high order component (e.g. a second order component (f 0 ±2f m )) and realizing a higher extinction ratio.
It is to be noted that the preferable embodiment of the above described optical modulator is an optical single side band modulator or an optical frequency shift keying modulator.
The present invention enables to provide an optical modulator which is capable of adjusting optical intensity of optical signals which contains non-desired components so that the intensity of the components become at a similar level, whereby the optical modulator is capable of effectively suppressing the non-desired components when the optical signals are combined.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram showing a basic arrangement of an optical modulator of the present invention.
FIG. 2 is a conceptual diagram showing optical signals and its phases in each part of an ideal optical FSK modulator (or an optical SSB modulator).
FIG. 3 is a conceptual diagram showing an example of a generation method of a carrier signal suppressed SSB (single side-band) modulation signal using the optical modulator of the present invention.
FIG. 4 is a conceptual diagram showing an example of a generation method of a carrier signal suppressed DSB modulation signal using the optical modulator of the present invention.
FIG. 5 is a schematic block diagram showing an optical modulator according to the fourth embodiment of the present invention.
FIG. 6 is a schematic block diagram showing an optical modulator according to the fifth embodiment of the present invention.
FIG. 7 is a diagram showing a basic arrangement of an FSK modulator of the present invention.
FIG. 8 is a schematic diagram showing a basic arrangement of a generator of a radio signal.
FIG. 9 is a schematic diagram showing a basic arrangement of a conventional optical modulation system acting as an optical SSB modulator or an optical FSK modulator.
FIG. 10 is a diagram showing an optical modulator described in FIG. 37 of Japanese Unexamined Patent Application Publication No. 2004-252386.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
1. Basic Arrangement of Optical Modulator of the Present Invention
Hereinafter, the present invention is explained in detail referring to figures. FIG. 1 is a schematic diagram showing a basic arrangement of an optical modulator of the present invention. As shown in FIG. 1 , the optical modulator according to the first aspect of the present invention comprises a first sub Mach-Zehnder waveguide (MZ A ) ( 2 ), a second sub Mach-Zehnder waveguide (MZ B ) ( 3 ), a main Mach-Zehnder waveguide (MZ C ) ( 8 ), a first electrode (RF A electrode) ( 9 ), a second electrode (RF B electrode) ( 10 ), a main Mach-Zehnder electrode (electrode C) ( 11 ), and an intensity modulator ( 12 ).
The main Mach-Zehnder waveguide (MZ C ) ( 8 ) includes an input part ( 4 ) of an optical signal, a branching part ( 5 ) where the optical signal is branched to the first sub Mach-Zehnder waveguide (MZ A ) and the second sub Mach-Zehnder waveguide (MZ B ), the first sub Mach-Zehnder waveguide (MZ A ), the second sub Mach-Zehnder waveguide (MZ B ), a combining part ( 6 ) combining the optical signals outputted from the first sub Mach-Zehnder waveguide (MZ A ) and the second sub Mach-Zehnder waveguide (MZ B ), an output part ( 7 ) outpuffing the optical signal combined at the combining part.
The first electrode (RF A electrode) ( 9 ) is one for inputting radio frequency (RF) signals to two arms composing the first sub Mach-Zehnder waveguide (MZ A ).
The second electrode (RF B electrode) ( 10 ) is one for inputting radio frequency (RF) signals to two arms composing the second sub Mach-Zehnder waveguide (MZ B ).
The main Mach-Zehnder electrode (electrode C) ( 11 ) is one for controlling a phase difference between an output signal from the first sub Mach-Zehnder waveguide (MZ A ) and an output signal from the second sub Mach-Zehnder waveguide (MZ B ) by applying voltage to the main Mach-Zehnder waveguide (MZ C ).
The intensity modulator ( 12 ) is provided on a waveguide portion between a combining part of the first sub Mach-Zehnder waveguide (MZ A ) and the combining part ( 6 ) of the main Mach-Zehnder waveguide (MZ C ) wherein the intensity modulator modulates intensity of the optical signal propagating through the waveguide portion.
The above arrangement of the present invention adjusts intensity levels of components to be suppressed (a carrier component (f 0 ) and a high order component (e.g. a second order component (f 0 ±2f m )) of output signals from each sub Mach-Zehnder waveguide to be about the same level. This enables to effectively suppress components to be suppressed when optical signals from each sub Mach-Zehnder are combined at the combining part ( 6 ).
Each sub Mach-Zehnder waveguide, for example, is provided with a waveguide of nearly hexagonal shape (which composes two arms of the Mach-Zehnder), and is provided with two parallel-aligned phase modulators. The phase modulators are, for example, realized by electrodes laid along with the waveguides. The intensity modulator is, for example, realized by a Mach-Zehnder waveguide and an electrode applying electric field to both arms of the Mach-Zehnder waveguide.
A Mach-Zehnder waveguide or an electrode is generally provided on a substrate. The material of the substrate and each waveguide is not specifically limited if light can propagate therethrough. For example, a lithium niobate waveguide with a Ti diffusion may be formed on an LN substrate, and a silicon dioxide (SiO 2 ) waveguide may be formed on a silicon (Si) substrate. Also, an optical semiconductor waveguide such as an InGaAsP waveguide (a GaAlAs waveguide) formed on an indium phosphide substrate (a GaAs substrate) may be used. The substrate is preferably formed of lithium niobate (LiNbO 3 : LN) and cut out in a direction orthogonal to the X-axis (X-cut), and light is propagated in a Z-axis direction (Z-axis propagation). This is because a low-power-consumption drive and a superior response speed can be achieved due to dynamic electrooptic effect. An optical waveguide is formed in the surface portion of a substrate having an X-cut plane (YZ plane), and guided light propagates along the Z-axis (the optic axis). A lithium niobate substrate except the X-cut may be used. As a substrate, it is possible to use a material of a one-axis crystal having a crystal system such as a trigonal system and a hexagonal system and having electro optical effect or a material in which a point group of a crystal is C 3V , C 3 , D 3 , C 3h , and D 3h . These materials have a refractive index adjusting function in which a change in the refractive index due to the application of an electric field has a different sign depending on a mode of a propagation light. As a specific example, lithium tantalite oxide (LiTO 3 : LT), β-BaB 2 O 4 (abbr. BBO), LiIO 3 and the like can be used other than lithium niobate.
The dimension of the substrate is not particularly limited if it is large enough to be able to form a predefined waveguide. The width, length, and the depth of each waveguide is also not particularly limited if the module of the present invention is able to fulfill its function. The width of each waveguide can be, for example, around 1 μm to 20 μm, preferably about 5 μm to 10 μm. The depth (the thickness) of waveguide can be 10 nm to 1 μm, preferably 50 nm to 200 nm.
It is to be noted that other than the above mentioned RF A electrode and RF B electrode, a bias adjustment electrode may be provided on a sub Mach-Zehnder waveguide, and also the above mentioned RF A electrode and RF B electrode may act as a bias adjustment electrode.
The first bias adjustment electrode (DC A electrode) is an electrode for controlling a phase of light propagating thorough the two arms of the MZ A by controlling bias voltage between two arms (path 1 and Path 3 ) composing the MZ A . On the other hand, the second bias adjustment electrode (DC B electrode) is an electrode for controlling a phase of light propagating thorough the two arms of the MZ B by controlling bias voltage between two arms (path 2 and Path 4 ) composing the MZ B . Direct current or low frequency signal is preferably applied to the DC A electrode and the DC B electrode in general. It is to be noted that “low frequency” of the low frequency electrode means frequency of, for example, 0 Hz to 500 MHz. A phase modulator for adjusting a phase of an electric signal is preferably provided at the output of the signal source of this low frequency signal in order to be able to control a phase of an output signal.
The first modulation electrode (RF A electrode) is an electrode for inputting a radio frequency (RF) signals to the two arms composing the MZ A . On the other hand, the second modulation electrode (RF B electrode) is an electrode for inputting radio frequency signals to the two arms composing the MZ B . The RF A electrode and the RF B electrode are, for example, traveling-wave-type electrodes or resonant-type electrodes, and preferably are resonant-type electrodes.
As explained above, two other electrodes may act as a DC A electrode and an RF A electrode separately, on the other hand, one electrode may act as those electrodes alone. In the latter case, a bias voltage and a radio frequency signal is applied to one electrode.
The RF A electrode and the RF B electrode are preferably connected to a high frequency signal source. The high frequency signal source is a device for controlling a signal transmitted to the RF A electrode and the RF B electrode. As the high frequency signal source, a publicly known high frequency signal source can be adopted. A range of frequencies (f m ) of the high frequency signals inputted to the RF A electrode and the RF B electrode is, for example, 1 GHz to 100 GHz. An output of a high frequency signal source is, for example, a sinusoidal wave having a fixed frequency. It is to be noted that a phase modulator is preferably provided at an output of this high frequency signal source in order to be able to control phases of output signals.
The RF A electrode and the RF B electrode are composed of e.g. gold, platinum or the like. The width of the RF A electrode and the RF B electrode is, for example, 1 μm to 10 μm, and is specifically 5 μm. The length of the RF A electrode and the RF B electrode is, for example, 0.1 times to 0.9 times the wavelength (f m ) of the modulation signal, including 0.18 to 0.22 times or 0.67 to 0.70 times. And more preferably, it is shorter than the resonant point of the modulation signal by 20 to 25%. This is because with such a length, the synthesized impedance with a stub electrode remains in an appropriate region. More specifically, the length of the RF A electrode and the RF B electrode is, for example, 3250 μm. Hereinafter, a resonant-type electrode and a traveling-wave-type electrode are described.
A resonant-type optical electrode (resonant-type optical modulator) is an electrode for performing a modulation by using resonance of a modulation signal. A known resonant-type electrode such as those described in the Japanese Patent Application Laid-Open 2002-268025, and [Tetsuya Kawanishi, Satoshi Oikawa, Masayuki Izutsu, “Planar Structure Resonant-type Optical Modulator”, TECHNICAL REPORT OF IEICE, IQE2001-3 (2001-05)] can be adopted as a resonant-type electrode.
A traveling-wave-type electrode (traveling-wave-type optical modulator) is an electrode (modulator) for modulating light while guiding waves so that a lightwave and an electric signal are guided in the same direction (e.g. Hiroshi Nishihara, Masamitsu Haruna, Toshiaki Suhara, “Optical Integrated Circuit” (revised and updated edition), Ohmsha, pp. 119-120). A publicly known traveling-wave-type electrode such as those described in Japan Patent Application Laid-Open Nos. 11-295674, 2002-169133, 2002-40381, 2000-267056, 2000-471159, and 10-133159, for example, can be adopted as a traveling-wave-type electrode.
As a preferable traveling-wave-type electrode, a so-called symmetrical-type earth electrode arrangement (one provided with at least a pair of earth electrodes on both sides of a traveling-wave-type signal electrode) is adopted. Thus, by symmetrically arranging the earth electrodes on both sides of the signal electrode, a high frequency wave outputted from the signal electrode is made easy to be applied to the earth electrodes arranged on the left and right side of the signal electrode, thereby suppressing an emission of a high frequency wave to the side of the substrate.
The RF electrode may act as both of the electrodes for the RF signal and the DC signal. Namely, either one of or both of the RF A electrode and the RF B electrode are connected to a feeder circuit (bias circuit) for supplying the DC signal and the RF signal mixed. Since the optical SSB modulator of this embodiment has the RF electrode connected to the feeder circuit (bias circuit), an RF signal (ratio frequency signal) and a DC signal (direct current signal: signal related to bias voltage) can be inputted to the RF electrode.
The main Mach-Zehnder electrode (electrode C) ( 11 ) is an electrode for controlling phase difference between an output signal from the first sub Mach-Zehnder waveguide (MZ A ) and an output signal from the second sub Mach-Zehnder waveguide (MZ B ) by applying voltage to the main Mach-Zehnder waveguide (MZ C ). As the electrode C, the electrode for the sub Mach-Zehnder explained above can be used as needed. Since a radio frequency signal as a modulation signal, for example, is applied to the electrode C, a traveling-wave-type electrode corresponding to the radio frequency signal is preferable for the electrode C. Since the phase difference of optical signals of both arms is controlled by the electrode C, a signal desired to be cancelled, e.g. an USB signal or an LSB signal, can be suppressed by reversing the phase of the signal. By performing this phase control at high speed, frequency shift keying can be realized.
A preferable embodiment of the above described optical modulator may be one wherein the main Mach-Zehnder electrode (electrode C) ( 11 ) comprises a first main Mach-Zehnder electrode (MZ CA electrode) ( 14 ) and a second main Mach-Zehnder electrode (MZ CB electrode) ( 15 ). The first main Mach-Zehnder electrode (MZ CA electrode) ( 14 ) is laid along at least a part of the waveguide between an output part of the first sub Mach-Zehnder waveguide (MZ A ) and the combining part. The second main Mach-Zehnder electrode (MZ CB electrode) ( 15 ) is laid along at least a part of the waveguide between an output part of the second sub Mach-Zehnder waveguide (MZ B ) and the combining part.
The optical modulator according to the above embodiment comprises the first main Mach-Zehnder electrode (MZ CA electrode) ( 14 ) and the second main Mach-Zehnder electrode (M B electrode) ( 15 ). The optical modulator is able to control optical phases of output signals from each sub Mach-Zehnder waveguide, thereby enabling to suppress carrier waves (carrier signals) or high order components (e.g. a second order component (f 0 ±2f m )) of the optical signals, when the optical signals are combined. Then the optical modulator can suppress a carrier component and high order components that should be suppressed.
The first main Mach-Zehnder electrode (MZ CA electrode) is one being laid along at least a part of the waveguide between an output part of the first sub Mach-Zehnder waveguide (MZ A ) and the combining part. And, “at least a part” is a length long enough to be able to adjust phase of an output signal. As this electrode, the same one provided on the sub Mach-Zehnder electrode is used.
The second main Mach-Zehnder electrode (MZ CB electrode) is one being laid along at least a part of the waveguide between an output part of the second sub Mach-Zehnder waveguide (MZ B ) and the combining part, which is the same as the MZ CA electrode ( 11 ). It is to be noted that the first main Mach-Zehnder electrode (MZ CA electrode) and the second main Mach-Zehnder electrode (MZ CB electrode) may be one that make the waveguide portion whereon each of the electrodes is provided act as an optical phase modulator.
The branching part ( 5 ) of the main MZ waveguide (MZ C ) is a part where optical signals branch into the first sub MZ waveguide (MZ A ) and the second sub MZ waveguide (MZ B ). The branching part ( 5 ) takes, for example, a Y-branching form. The combining part ( 6 ) is a part where optical signals outputted from the first sub MZ waveguide (MZ A ) and the second sub MZ waveguide (MZ B ) are combined. The combining part ( 6 ) takes, for example, a Y-branching form. The above Y-branching formed parts may be symmetry or asymmetry. As the branching part ( 5 ) or the combining part ( 6 ), a directional coupler may be used.
A preferable embodiment of the above described optical modulator is one that is provided with an asymmetric directional coupler at the branching part ( 5 ) of the main MZ waveguide (MZ C ) ( 8 ), and the directional coupler controls intensity so that intensity of the optical signal branched to the first sub MZ waveguide (MZ A ) is larger than that of the optical signal branched to the second sub MZ waveguide (MZ B ).
In intensity modulation by the intensity modulator ( 12 ), if a difference between components to be modulated is small, the intensity must be adjusted to be a little smaller, and if optical intensity of an optical signal from the MZ A is lower than that from MZ B , components desired to be suppressed cannot be effectively suppressed by the intensity modulator ( 12 ). However, the optical modulator described above can effectively use the intensity modulator ( 12 ), because the intensity of an optical signal heading toward the MZ A which has the intensity modulator can be increased in advance compared to the intensity of an optical signal heading toward the MZ B .
It is preferable for the optical modulator of the present invention to be provided with a control part electrically (or optically) connected to a signal source of each electrode so as to adequately control timing and phase of signals applied to each electrode. The control part acts as adjusting modulation time of a modulation signal applied to the first electrode (RF A electrode) and the second electrode (RF B electrode) and a modulation signal applied to the first main Mach-Zehnder electrode (MZ CA electrode) and the second main Mach-Zehnder electrode (MZ CB electrode). In other words, the control part adjusts considering propagation time of light so that modulation by each electrode is performed to a certain signal. This modulation time is adequately adjusted based on, for example, a distance between each electrode.
A control part, for example, is one adjusting voltage applied to the first main Mach-Zehnder electrode (MZ CA electrode) and the second main Mach-Zehnder electrode (MZ CB electrode) so that phase difference of optical carrier signals or certain high order optical signals contained in output signals from the first waveguide (MZ A ) and the second waveguide (MZ B ) is 180 degrees. This control part, for example, is a computer which is connected to signal sources of each electrode and stores a processing program. When the computer receives an input of control information from an input device such as a keyboard, a CPU reads out, for example, a processing program stored in a main program, and reads out necessary information from memories based on an order of the processing program, rewrites information stored in memories as needed, and outputs an order, which controls timing and phase difference of an optical signal outputted from a signal source, to signal source from an external output device. As the processing program, one that makes a computer have the following two means is adopted. One is a means for grasping phase of a certain component on each sub Mach-Zehnder, and the other is a means for generating an order to adjust a modulation signal applied to the first main Mach-Zehnder electrode (MZ CA electrode) and the second main Mach-Zehnder electrode (MZ CB electrode), so that the phase of a certain component is reversed, by using phase information of a certain information grasped by the means for grasping.
It is to be noted that the above described optical modulator can be used as an optical single side band modulator, an optical frequency shift keying modulator or a DSB-SC modulator, but preferably used as an optical single side band modulator or an optical frequency shift keying modulator.
2. Operation Example of Optical Modulator
Hereinafter, an operation example of the optical modulator is described. For example, sinusoidal RF signals of 90 degrees phase difference are applied to parallel aligned four optical modulators (composing RF A electrode and RF B electrode) of the sub MZ waveguide. And with respect to light, bias voltages are applied to the DC A electrode and the DC B electrode so that phase differences of the optical signals are respectively 90 degrees. These phase differences of the electric signals and the optical signals are adjusted as needed, but are basically adjusted to be an integral multiple of 90 degrees.
FIG. 2 is a conceptual diagram showing optical signals and its phases in each part of an ideal optical FSK modulator (or an optical SSK modulator). As shown in FIG. 2 , a carrier and the like are ideally suppressed, and at point P and point Q of FIG. 1 , LSB signals from the MZ A and the MZ B are adjusted to be in opposite phase. The signals adjusted in this way are combined at the combining part ( 6 ) where the LSB components cancel each other and only the USB components remain. On the other hand, if the phase difference of the output signal from the electrode C is adjusted to be 270 degrees, the USB signals cancel each other and the LSB signals remain. But, in reality, carrier waves (carrier signals) or a high order component (e.g. a second order component (f 0 ±2f m )) of optical signals are included in these optical signals.
The phases of carrier waves (carrier signals) and a high order component (e.g. a second order component (f 0 ±2f m )) of optical signals outputted from each sub Mach-Zehnder waveguide are decided by phase or bias voltage of signals applied to each sub Mach-Zehnder waveguide. Therefore, components to be suppressed are effectively suppressed by adjusting phases of output signals from each sub Mach-Zehnder waveguide, so that the phases of components to be suppressed (carrier waves (carrier signals) of an optical signal or a high order component (e.g. a second order component (f 0 ±2f m )) are reversed, before combined at the combining part.
FIG. 3 is a conceptual diagram showing an example of a generation method of a carrier signal suppressed SSB (single side-band) modulation signal using the optical modulator of the present invention. As shown in FIG. 3 , carrier signals having the same phase, for example, remain in the optical signals obtained in each sub Mach-Zehnder waveguide. By adjusting a phase difference of each optical signal to be 180 degrees, the phase difference of carrier components at point P and point Q of FIG. 1 assumes 180 degrees. And, the carrier components of the above adjusted optical signal are modulated by the intensity modulator so as to be about the same level. When the above adjusted optical signals are combined at the combining part ( 6 ), carrier components are suppressed by canceling each other. On the other hand, the upper side band components (USB): +1 are not suppressed and remain, because the phases are not reversed. But the lower side band components (LSB) are suppressed by canceling each other, because the phases are reversed. This enables to generate a signal with high extinction ratio by effectively suppressing carrier components of an output signal outputted from the optical modulator.
It is to be noted that the components to be suppressed, such as carrier components, cannot be adjusted to be exactly the same level. Therefore, a ratio of components to be suppressed at each MZ A and MZ B is arranged to be, for example, 1:2 to 2:1, as an integrated intensity. The ratio is arranged preferably to be 2:3 to 3:2, and may be 4:5 to 5:4.
In the above, an optical FSK modulator performing high speed modulation on a USB signal and an LSB signal is explained. But the optical modulator of the present invention can be used in the same way as an optical SSB modulator which is used by fixing either one of USB signal or LSB signal.
FIG. 4 is a conceptual diagram showing an example of a generation method of a carrier signal suppressed DSB modulation signal using the optical modulator of the present invention. As shown in FIG. 4 , carrier signals having the same phase, for example, remain in the optical signals obtained in each sub Mach-Zehnder waveguide. By adjusting a phase difference of each optical signal to be 180 degrees, the phase difference of carrier components at point P and point Q of FIG. 1 assumes 180 degrees. Then, the intensities of the carrier components are adjusted to be about the same level. When the above adjusted optical signals are combined at the combining part ( 6 ), carrier components are suppressed by canceling each other. On the other hand, the upper side band components (USB): +1 and the lower side band components (LSB): −1 are not suppressed but remain, because the phases are not reversed, and the DSB-SC modulation is realized.
3. Manufacturing Method of Optical Modulator of the Present Invention
As a forming method of an optical waveguide, a publicly know forming method of the internal diffusion method such as the titanium diffusion method or a proton exchange method and the like can be used. In other words, the optical FSK modulator of the present invention, for example, can be manufactured by the following method. Firstly, an optical waveguide is formed by patterning titanium on the surface of a wafer of lithium niobate by photolithography method, and spreading titanium by thermal diffusion method. This is subject to the following conditions. The thickness of titanium is 100 to 2000 angstrom, diffusion temperature is 500 to 2000° C., and diffusion time is 10 to 40 hours. An insulating buffer layer of silicon dioxide (thickness of 0.5 to 2 μm) is formed on a principle surface of the substrate. Secondly, an electrode with metal plating with thickness of 15 to 30 μm is formed on the buffer layer. And lastly, the wafer is cut off. By these processes, an optical modulator formed with titanium-diffused waveguide is manufactured.
Optical FSK modulator, for example, can be manufactured by the following process. A waveguide can be provided on the substrate surface of lithium niobate by proton exchange method or titanium thermal diffusion method. For example, Ti metal stripe (length of few μm) is formed in a row on an LN substrate by photolithographic technique. Subsequently, Ti metal is diffused into the substrate by exposing the LN substrate to heat (about 1000° C.). Through this process, a waveguide can be formed on an LN substrate.
Also, an electrode is manufactured in the same way as the above process. For example, in the same way as a formation of an optical waveguide, by using photolithography technique, an electrode can be formed on both sides of a plurality of waveguides which are formed in the same breadth, the electrode being formed so that the interelectrode gap is about 1 μm to 50 μm.
In case of manufacturing an electrode using silicon substrate, the manufacturing process, for example, is as follows. A lower cladding layer is disposed on a silicon (Si) substrate by the flame hydrolysis deposition method, the lower cladding layer being composed mostly of silicon dioxide (SiO 2 ). And then a core layer is deposed, the core layer being composed mostly of silicon dioxide (SiO 2 ) to which germanium dioxide (GeO 2 ) is added as a dopant. Subsequently, vitrification is performed in an electric furnace. And then, an optical waveguide is formed by etching and an upper cladding layer is disposed, the upper cladding layer being composed mostly of silicon dioxide (SiO 2 ). And then, a thin-film heater thermooptic intensity modulator and a thin-film heater thermooptic phase modulator are formed on the upper cladding layer.
4. Second Embodiment
A preferable embodiment of the optical modulator is one further comprising an asymmetric directional coupler provided at the branching part ( 5 ) of the main Mach-Zehnder waveguide (MZ C ) ( 8 ). The asymmetric directional coupler controls intensity of the optical signal branched to the first sub Mach-Zehnder waveguide (MZ A ) so that the intensity of the optical signal branched to the first sub Mach-Zehnder waveguide (MZ A ) is higher than intensity of the optical signal branched to the second sub Mach-Zehnder waveguide (MZ B ).
If the intensity difference between components to be suppressed is small, the intensity modulator ( 12 ) is required to lessen the intensity of one of the component minutely. Further if optical intensity of an optical signal from the MZ A is weaker than that from MZ B , components to be suppressed cannot be effectively suppressed by the intensity modulator ( 12 ). On the contrary, the optical modulator described above can effectively use the intensity modulator ( 12 ), because the intensity of an optical signal heading toward the MZ A which has the intensity modulator can be higher than the intensity of an optical signal heading toward the MZ B .
If a ratio of intensity branch is too small, asymmetric configuration has no meaning. On the other hand, if the ratio is too large, intensity of the entire optical signal must be reduced. From this perspective, an intensity branch ratio (MZ A /MZ B ), for example, is from 1.01 to 5 both inclusive, from 1.1 to 3 both inclusive is preferable, and the ratio may also be from 1.3 to 1.5 both inclusive. Increasing the branch ratio of MZ A this way, by adjusting intensity considering the branch ratio at the intensity modulator ( 12 ), intensity of components desired to be suppressed can be effectively adjusted.
5. Third Embodiment
While not specifically shown in figures, the other preferable embodiment of the present invention is one further comprising the intensity modulator ( 12 ) provided on a waveguide portion between a combining part of the second sub Mach-Zehnder waveguide (MZ B ) and the combining part ( 6 ) of the main Mach-Zehnder waveguide (MZ C ). The intensity modulator modulates intensity of the optical signal propagating through the waveguide portion.
It is to be noted that an optical modulator further comprising the intensity modulator ( 12 ) provided on between the output part of the MZ B and the combining part ( 6 ) is the other embodiment of the present invention. In this case, components desired to be suppressed can be adjusted and suppressed, regardless of which intensity is stronger between the optical signals from the MZ A and the optical signal from the MZ B .
6. Fourth Embodiment
FIG. 5 is a schematic block diagram showing an optical modulator according to the fourth embodiment of the present invention. As shown in FIG. 5 , an optical modulator according to this embodiment further comprises an intensity modulator ( 13 ) provided on one of two arms composing the first sub Mach-Zehnder waveguide (MZ A ) or one of two arms composing the second sub Mach-Zehnder waveguide (MZ B ) or two or more of the waveguides. The intensity modulator ( 13 ) modulates intensity of the optical signals propagating through the waveguides
The arm (Path of FIG. 1 ) whereon the intensity modulator ( 13 ) is provided may be either one of Path 1 , Path 2 , Path 3 , or Path 4 . It may also be either one of Path 1 and Path 2 , Path 1 and Path 3 , or Path 1 and Path 4 . It may also be either one of Path 2 and Path 3 , or Path 2 and Path 4 . It may also be Path 3 and Path 4 . It may also be Path 1 , Path 2 and Path 3 . It may also be Path 1 , Path 2 and Path 4 . It may also be Path 1 , Path 3 and Path 4 . It may also be Path 2 , Path 3 and Path 4 . It may also be all the Paths.
One that acts as the intensity modulator ( 13 ) provided on the sub Mach-Zehnder waveguide is not specifically limited, but is, for example, one that has a sub Mach-Zehnder waveguide and an electrode applying electric field to the sub Mach-Zehnder waveguide.
In this embodiment, since it is possible to adjust intensity of a certain component from the sub Mach-Zehnder in advance, it is possible to suppress components desired to be suppressed more effectively.
7. Fifth Embodiment
FIG. 6 is a schematic block diagram showing an optical modulator according to the fifth embodiment of the present invention. As shown in FIG. 6 , this optical modulator has basically the same arrangement as the optical modulator shown in FIG. 1 described above. But the main Mach-Zehnder electrode (electrode C) ( 11 ) of the optical modulator comprises a first main Mach-Zehnder electrode (MZ CA electrode) ( 14 ) and a second main Mach-Zehnder electrode (MZ CB electrode) ( 15 ). The first main Mach-Zehnder electrode (MZ CA electrode) ( 14 ) is laid along at least a part of the waveguide between an output part of the first sub Mach-Zehnder waveguide (MZ A ) and the combining part. The second main Mach-Zehnder electrode (MZ CB electrode) ( 15 ) is laid along at least a part of the waveguide between an output part of the second sub Mach-Zehnder waveguide (MZ B ) and the combining part.
The optical modulator according to the above embodiment is provided with the first main Mach-Zehnder electrode (MZ CA electrode) ( 14 ) and the second main Mach-Zehnder electrode (MZ CB electrode) ( 15 ). This configuration enables the optical modulator to control optical phase of an output signal from the each sub Mach-Zehnder waveguide, thereby suppressing carrier waves (carrier signals) or a high order component (e.g. a second order component (f 0 ±2f m ) of optical signals to be combined.
The second main Mach-Zehnder electrode (MZ CB electrode) is one being laid along at least a part of the waveguide between an output part of the second sub Mach-Zehnder waveguide (MZ B ) and the combining part, which is the same as the MZ CA electrode ( 11 ). It is to be noted that the first main Mach-Zehnder electrode (MZ CA electrode) and the second main Mach-Zehnder electrode (MZ CB electrode) may be one that make the waveguide portion whereon each of the electrodes is provided act as an optical phase modulator.
It is preferable for the optical modulator of the present invention to be provided with a control part electrically (or optically) connected to a signal source of each electrode so as to adequately control timing and phase of signals applied to each electrode. The control part act as adjusting modulation time of a modulation signal applied to the first electrode (RF A electrode) and the second electrode (RF B electrode) and a modulation signal applied to the first main Mach-Zehnder electrode (MZ CA electrode) and the second main Mach-Zehnder electrode (MZ CB electrode). In other words, the control part adjusts considering propagation time of light so that modulation by each electrode is performed to a certain signal. This modulation time is adequately adjusted based on, for example, a distance between each electrode.
A control part, for example, is one adjusting voltage applied to the first main Mach-Zehnder electrode (MZ CA electrode) and the second main Mach-Zehnder electrode (MZ CB electrode) so that phase difference of optical carrier signals or certain high order optical signals contained in output signals from the first waveguide (MZ A ) and the second waveguide (MZ B ) is 180 degrees. This control part, for example, is a computer which is connected to signal sources of each electrode and stores a processing program. When the computer receives an input of control information from an input device such as a keyboard, a CPU reads out, for example, a processing program stored in a main program, and reads out necessary information from memories based on an order of the processing program, rewrites information stored in memories as needed, and outputs an order, which controls timing and phase difference of an optical signal outputted from a signal source, to signal source from an external output device. As the processing program, one that makes a computer have the following two means is adopted. One is a means for grasping phase of a certain component on each sub Mach-Zehnder, and the other is a means for generating an order to adjust a modulation signal applied to the first main Mach-Zehnder electrode (MZ CA electrode) and the second main Mach-Zehnder electrode (MZ CB electrode), so that the phase of a certain component is reversed, by using phase information of a certain information grasped by the means for grasping.
Hereinafter, an operation example of the optical modulator according to the above embodiment is described. For example, sinusoidal RF signals of 90 degrees phase difference are applied to parallel aligned four optical modulators (composing the RF A electrode and RF B electrode) of the sub MZ waveguide. And with respect to light, bias voltages are applied to the DC A electrode and the DC B electrode so that phase differences of the optical signals become respectively 90 degrees. These phase differences of the electric signals and the optical signals are adjusted as needed, but are basically adjusted to be an integral multiple of 90 degrees.
Ideally, light whose frequency is shifted by frequency of each RF signal is outputted from the sub Mach-Zehnder waveguide. But, in reality, these optical signals contain carrier waves (carrier signals) or a high order component (e.g. a second order component (f 0 ±2f m )) of the optical signals. The optical modulator of the present invention performs to suppress at least one or more of carrier waves (carrier signals) and a high order component (e.g. a second order component (f 0 ±2f m )) of the optical signals.
The phases of carrier waves (carrier signals) and a high order component (e.g. a second order component (f 0 ±2f m )) of optical signals outputted from each sub Mach-Zehnder waveguide are decided by phase or bias voltage of a signal applied to each sub Mach-Zehnder waveguide. Therefore, components desired to be suppressed are effectively suppressed by adjusting phases of output signals from each sub Mach-Zehnder waveguide, so that the phases of components desired to be suppressed (carrier waves (carrier signals) of optical signals or a high order component (e.g. a second order component (f 0 ±2f m )) are reversed, before combined at the combining part.
It is to be noted that the optical modulator acts as a DSC-SC modulator, an FSK modulator, an SSK modulator etc. by controlling optical signal components canceling each other, but preferably used as a DSC-SC modulator.
8. Sixth Embodiment
A preferable embodiment of the optical modulator of the present invention is the above described optical modulator further comprising a control part for controlling a signal source applying a signal to the first electrode (RF A electrode) ( 9 ), the second electrode (RF B electrode) ( 10 ), and the main Mach-Zehnder electrode (electrode C) ( 11 ). And the control part makes the signal source to (i) adjust bias voltage applied to the main Mach-Zehnder waveguide (MZ C ) and bias voltage applied to the first sub Mach-Zehnder waveguide (MZ A ) and the second sub Mach-Zehnder waveguide (MZ B ) so that an output from the main Mach-Zehnder waveguide (MZ C ) is increased, (ii) adjust bias voltage applied to the main Mach-Zehnder waveguide (MZ C ) so that an output from the main Mach-Zehnder waveguide (MZ C ) is decreased, (iii) decrease bias voltage applied to the first sub Mach-Zehnder waveguide (MZ A ) or the second sub Mach-Zehnder waveguide (MZ B ) so that an output from the main Mach-Zehnder waveguide (MZ C ) is decreased, and (iv) adjust bias voltage applied to the main Mach-Zehnder waveguide (MZ C ) so that an output from the main Mach-Zehnder waveguide (MZ C ) is decreased.
By using an optical modulator of this embodiment, it is possible to adjust bias voltage applied to each electrode adequately, thereby suppressing a carrier component (f 0 ) and a high order component (e.g. a second order component (f 0 ±2f m )) and realizing higher extinction ratio.
It is basically one that comprises the steps of (i) adjusting bias voltage of the main Mach-Zehnder electrode (electrode C) and bias voltage of the two sub Mach-Zehnder electrode so that output from the main Mach-Zehnder waveguide is increased, (ii) adjusting bias voltage of electrode C so that output from the main Mach-Zehnder waveguide is decreased, (iii) decreasing bias voltage of either one of the sub Mach-Zehnder electrode so that output from the main Mach-Zehnder waveguide is decreased, (iv) adjusting bias voltage of the electrode C so that output from the main Mach-Zehnder waveguide is decreased. It is to be noted that repeating the above step (iii) and step (iv) is the preferable embodiment of the present invention. Hereinafter, each step is explained.
(i) Step of Adjusting Bias Voltage of the Electrode C and Bias Voltage of the Two Sub Mach-Zehnder Electrode so that Output from the Main Mach-Zehnder Waveguide is Increased.
In this step, the bias voltage of the electrode C and the bias voltage of two sub MZ electrode is adjusted so as to increase output from the main Mach-Zehnde waveguide (preferably increased as much as possible, more preferably maximized). Since the main Mach-Zehnde waveguide is connected to a measurement system not shown in figures, the bias voltage applied to each Mach-Zehnder electrode may be adjusted by observing output levels of the measurement system.
The measurement system may be connected to a power supply system supplying each bias voltage via a control device, and each bias voltage may be controlled so that optical intensity measured by the measurement system is increased. The control device is provided with an input part, an output part, a memory part (including memory and main memory), a computing part, wherein the input part inputs information, the output part outputs information, the memory part stores information, and the computing part such as CPU performs arithmetic operations. Information on optical intensity measured by the measurement system is inputted to the control device by the input part, and stored in the memory. The CPU of the control device, based on an order from a controlling program of the main memory, retrieves the information on optical intensity from the memory. Also, the CPU of the control device, based on an order from a controlling program of the main memory, outputs a signal changing bias voltages applied to either one of or two or more of electrodes from the output part. This process changes the intensity level of output light. The control device, retrieving the information and comparing it to the former optical intensity, outputs an order of changing bias voltages so as to increase the optical intensity from the output part. A power source which received this output signal, based on the order, changes voltage levels applied to each electrode, thereby increasing the optical output.
(ii) Step of Adjusting Bias Voltage of Electrode C so that Output from the Main Mach-Zehnder Waveguide is Decreased.
This step is one for adjusting bias voltage applied to the main Mach-Zehnder electrode so that intensity of output light from the main Mach-Zehnder waveguide is decreased. Since the main MZ waveguide is connected to a measurement system not shown in figures, the bias voltage applied to the main Mach-Zehnder electrode may be adjusted by observing output levels of the measurement system.
The measurement system may be connected to a power supply system supplying bias voltage to the main Mach-Zehnder electrode via a control device, and the bias voltage may be controlled so that optical intensity measured by the measurement system is decreased. Information on optical intensity measured by the measurement system is inputted to the control device by the input part, and stored in the memory. The CPU of the control device, based on an order from a controlling program of the main memory, retrieves the information on optical intensity from the memory. Also, the CPU of the control device, based on an order from the controlling program of the main memory, outputs a signal changing bias voltages applied to the main Mach-Zehnder electrode from the output part. This process changes the intensity level of output light. The control device, retrieving the information and comparing it to the former optical intensity, outputs an order of changing bias voltages so as to decrease the optical intensity from the output part. A power source which received this output signal, based on the order, changes voltage levels applied to the main Mach-Zehnder electrode, thereby decreasing the optical output.
(iii) Step of Decreasing Bias Voltage of Either One of the Sub Mach-Zehnder Electrode so that Output from the Main Mach-Zehnder Waveguide is Decreased.
In this step, bias voltage of either one of the sub Mach-Zehnder electrodes is decreased so that output from the main Mach-Zehnder waveguide is decreased. In this step, if bias voltage of either one of the sub Mach-Zehnder electrodes is decreased, output from the main Mach-Zehnder waveguide is decreased. Therefore, bias voltage of the sub Mach-Zehnder electrode, to which output from the main Mach-Zehnder waveguide is decreased, is adjusted to be decreased. In this step, voltage level to be increased or decreased may be predetermined. A range of voltage level change is, for example, from 0.01V to 0.5V, and is preferably from 0.05V to 0.1V. By this step, output intensity from the main Mach-Zehnder is decreased. Since the main Mach-Zehnder waveguide is connected to a measurement system not shown in figures, the bias voltage may be adjusted by observing output levels of the measurement system.
The measurement system may be connected to a power supply system supplying bias voltage to the electrode A and the electrode B via a control device, and the bias voltage applied to the electrode A or the electrode B may be controlled. In this case, information on an electrode whose voltage level is changed and information on voltage level to be changed may be stored in a memory and the like. The CPU of the control device, based on an order from a controlling program of the main memory, retrieves control information from the memory, and outputs a signal changing bias voltage applied to the electrode A and electrode B. This changes bias voltage applied to the electrode A or the electrode B by a certain amount. And if the bias voltage applied to the electrode A or the electrode B changes by a certain amount, intensity of an optical signal from the main Mach-Zehnder changes. The information on optical intensity observed by the measurement system is inputted from the input part and stored in the memory. The CPU of the control device, based on an order from the controlling program of the main memory, retrieves information on optical intensity stored in the memory, outputs an order from the output part. The order is to change bias voltages applied to the sub Mach-Zehnder electrodes so as to decrease optical intensity from the main Mach-Zehnder waveguide. The power source, having received this output signal, changes the voltage level applied to electrodes based on the order, thereby decreasing optical output.
(iv) Step of Adjusting Bias Voltage of the Electrode C so that Output of the Main Mach-Zehnder Waveguide is Decreased.
This step is one for adjusting bias voltage of electrode C so as to decrease output of the main Mach-Zehnder waveguide. Since the main MZ waveguide is connected to a measurement system not shown in figures, for example, the bias voltage may be adjusted by observing output levels of the measurement system. It is to be noted that this step or the above step (iii) and this step may be repeatedly performed.
The measurement system may be connected to a power supply system supplying bias voltage to the electrode C via a control device, and bias voltage applied to the electrode C may be adjusted. The CPU of the control device, based on an order from a controlling program of the main memory, retrieves control information from the memory, and outputs a signal changing bias voltage applied to the electrode C from output part. This changes bias voltage applied to the electrode C by a certain amount.
Also, the CPU of the control device, based on an order from a controlling program of the main memory, retrieves control information or information on output light from the memory, and may make a decision to stop adjusting bias voltage. To the contrary, the CPU may keep adjusting bias voltage by feeding back intensity information of an output light from the measurement system.
9. Optical Communication System
The optical communication system according to the second aspect of the present invention is one comprising the optical modulator ( 1 ), a demodulator ( 21 ) demodulating an output signal from the optical modulator, and an optical path connecting the optical modulator and the demodulator. FIG. 7 shows a basic arrangement of an FSK modulator of the present invention.
As shown in FIG. 7 the FSK modulator ( 21 ) of the present invention comprises a branching filter ( 22 ) for branching an optical signal according to wavelength thereof, a means ( 23 ) for adjusting a delay time of two lights branched by the branching filter, a first photodetector ( 24 ) for detecting one optical signal branched by the branching filter, a second photodetector ( 25 ) for detecting a remaining optical signal branched by the branching filter, and a means ( 26 ) for calculating a difference between an output signal of the first photodetector and an output signal of the second photodetector.
31 of FIG. 7 and FIG. 8 represents the optical modulator ( 1 ) above explained, 32 represents a signal source, 33 represents a light path such as an optical fiber, and 34 represents a control device such as a computer.
“A means for branching an optical signal transmitted from the transmitter according to wavelengths thereof” is, for example, a branching filter (hereinafter, this means is occasionally referred to as “branching filter”). As the branching filter ( 22 ), a publicly known branching filter such as an interleaver can be adopted. Since the light branched by the branching filter is an optical FSK signal, one that branches into an upper side band (USB) signal and a lower side band (LSB) signal of the optical FSK signal is used. The interleaver is a device having a characteristic that can branch an incoming wavelength multiplexed optical signal into a pair signal systems whose wavelength interval is doubled and conversely combines a pair of wavelengths multiplexed signals into one signal system whose wavelength interval is halved. According to the interleaver, a sharp signal transmitting wavelength region can be obtained, so that signals of adjacent channels can be reliably separated, thereby preventing a mixture of another wavelength and a degradation of the communication quality. An interleaver is, for example, a fiber-type interleaver including a plurality of fiber computers, a multilayered interleaver including a multilayered film and a prism, a multiple inflection plate-type interleaver including a multiple inflection plate and a polarized wave separating device, and a waveguide-type interleaver using a waveguide. More specifically, it is Nova-Interleavers manufactured by Optoplex Corporation, OC-192 and OC-768 manufactured by Nexfon Corporation.
“A means for adjusting a delay time of two lights branched by the branching filter” is, for example, a publicly known delay adjusting apparatus (hereinafter, this means is also called as “delay adjusting apparatus”). As such a delay adjusting apparatus, a delay adjusting apparatus which is composed of a plurality of mirrors and capable of adjusting an optical path length can be used. The delay time (in other words, a mirror position) of this delay adjusting apparatus may be adjustable automatically as appropriate, or may be fixed.
As “a means for detecting one optical signal (λ 1 ) branched by the branching filter” and “a means for detecting a remaining optical signal (λ 2 ) branched by the branching means”, a publicly known photodetector can be used (hereinafter, this means is also called “photodetector”). The photodetector, for example, detects an optical signal and converts it into an electric signal. Intensity and the like of an optical signal can be detected by the photodetector. As the photodetector, devices including a photodiode, for example, can be adopted. It is to be noted that the optical signal (λ 1 ) and the optical signal (λ 2 ) are the USB signal and the LSB signal that are optical signals having shifted the frequency upwards or downwards by a modulating frequency compared to carrier wave.
As “a means ( 26 ) for calculating a difference between an output signal of the first photodetector and an output signal of the second photodetector”, a publicly known subtractor can be used (hereinafter, this means is also called “subtractor”). As a subtractor, a device including a computational circuit and the like for calculating a difference between an output signal of the first photodetector and an output signal of the second photodetector can be used.
The FSK demodulator of the present invention may include publicly known arrangements other than those mentioned above to be used for the demodulator. While not specifically shown in figures, one provided with a dispersion compensating apparatus on an optical path after the branching filter ( 22 ) is preferable. This is because such a dispersion compensating apparatus can compensate the light scattered by the optical fiber and the like.
While not specifically shown in figures, one provided with an optical amplifier on an optical path after the branching filter ( 22 ) is preferable. The optical signal outputted from the branching filter such as an interleaver may assume smaller amplitude. Therefore, by restoring the amplitude by the optical amplifier, a communication over a long distance can be endured. Such an optical amplifier is preferably provided for each of the USB signal and the LSB signal.
Hereinafter, an operation of the FSK demodulator will be described. The FSK demodulator ( 21 ) receives an optical FSK signal. Then, the branching filter ( 22 ) branches the optical signal transmitted from a transmitter according to the wavelengths thereof, thereby branching into the USB light (λ 1 ) and the LSB light (λ 2 ). The delay adjusting apparatus ( 23 ) eliminates the delay time of the USB light (λ 1 ) and the LSB light (λ 2 ), for example, by adjusting an optical path length according to the delay time. The first photodetector ( 24 ) detects one optical signal branched by the branching filter to be converted into an electric signal. The second photodetector ( 25 ) detects a remaining optical signal branched by the branching filter to be converted into an electric signal. The subtractor ( 26 ) calculates a difference between an output signal of the first photodetector and an output signal of the second photodetector. Then the signal obtained by the subtractor is outputted to a monitor or the like which is not shown. Thus, an FSK signal demodulation having solved the problem of an optical delay due to a dispersion of light is made possible.
10. Radio Signal Generator
FIG. 8 is a block diagram showing a basic arrangement of a radio signal generator according to the third aspect of the present invention. As shown in the FIG. 8 , the radio signal generator is provided with an optical modulator ( 1 ) connectable with an optical source, a photodetector ( 36 ) detecting an output light from the modulated optical signal generator, and an antenna ( 35 ) converting an optical signal detected by the photodetector to a radio signal.
A photodetector is a means for detecting an output light from a modulated optical signal generator, and converting the output light to an electric signal. As the photodetector, a publicly known photodetector can be adopted, and a device including photodiode, for example, can be adopted. As the photodetector, for example, one detecting an optical signal and converting it to an electric signal can be used. Intensity, frequency, etc of an optical signal can be detected by the photodetector. As the photodetector, for example, one described in [Hirho Yonetsu, “Optical Communication Element Engineering (light-emitting light-receiving element)” Kougakutosyo Ltd. the 6th edition, 2000] can be adopted as needed.
An antenna is a means for emitting an electrical signal converted by the photodetector as a radio signal. As an antenna, a publicly known antenna can be used. The optical modulator ( 1 ) generates a modulated signal. The modulated signal is detected by the photodetector, and then the modulated signal is converted to a radio signal and emitted as a radio signal by an antenna. This enables to generate a radio signal.
The optical modulator of the present invention can be effectively used in the field of optical information communication. | It is an object of the present invention to provide an optical modulator which is capable of adjusting optical intensity of optical signals which contains non-desired components so that the intensity of the components become at a similar level, whereby the optical modulator is capable of effectively suppressing the non-desired components when the optical signals are combined. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to networked systems composed of a plurality of devices clustered for the exchange of data and control messages formatted according to predetermined protocols and, in particular although not essentially, to such systems where inter-device communication between some of the devices is via wireless link. The invention further relates to devices for use in groups or clusters to form such systems.
Networked interconnection of devices has long been known and used, starting from basic systems where different system functions have been provided by separate units, for example hi-fi systems or security systems having detectors, a control panel and one or more alarm sounders. A development has been the so-called home bus systems where a greater variety of products have been linked with a view to providing enhanced overall functionality in for example domestic audio/video apparatus coupled with a home security system and the use of telephone. An example of such a home bus system is the domestic digital bus (D2B), the communications protocols for which have been issued as standard IEC 1030 by the International Electrotechnical Commission in Geneva, Switzerland. The D2B system provides a single wire control bus to which all devices are interfaced with messages carried between the various devices of the system in a standardised form of data packet.
With all such domestic equipment interconnection schemes, there is a problem of connection to apparatus not supporting the communications protocols of the scheme. As an example, a user may have a music system comprising interconnected units such as a compact disc (CD) player, amplifier, tuner and cassette player which communicate with each other using a first set of communications protocols, together with an audio visual system comprising for example a television, video recorder and satellite receiver which communicate using a second set of protocols. In the absence of a certain degree of compatibility with existing systems, a user may be faced with having to replace many items at one time. One way to reduce this problem is to provide a gateway device which supports two or more sets of communications protocols and can “translate” messages between them, as described in U.S. Pat. No. 5,754,548 (Hoekstra et al), where D2B is used as a subsystem within a home electronic bus (HEB) system.
As is also described in U.S. Pat. No. 5,754,548, such gateway devices can be used as part of a link between two clusters of bus-connected devices supporting the same communications protocols, but with different protocols governing communications on the link between the clusters. The link between the clusters may, for example, comprise a wireless (infra-red or RF) channel between the two gateway devices, whilst the cluster devices themselves are hard wired to respective serial data buses.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a networked system of devices including one or more communications links capable of handling digital data.
In accordance with a first aspect of the present invention there is provided a local communication system comprising:
a first cluster of devices interconnected for the communication of messages via a first data bus and in accordance with a first set of communication protocols; a second cluster of devices interconnected for the communication of messages via a second data bus and in accordance with said first set of communication protocols; and a data channel linking a device of said first cluster and a device of said second cluster, said data channel supporting communication of messages in accordance with a second set of communications protocols; wherein a device of the first cluster holds a stored software representation of operational features of a selected device of the second cluster and any device of the first cluster wishing to interact with said selected device instead interacts with said stored representation. As will be described hereinafter, interaction with a locally held proxy avoids the need for rewriting of cluster communications protocols simply to accommodate different transport capabilities and/or conditions on the bridge.
The stored representation may be generated by the said selected device and transmitted via said data channel to said device of the first cluster, and the said stored representation may be modified in response to limitations of said data channel, in which case the modification may occur on receipt by said device of the first cluster, in response to limitations of said data channel.
The stored representation may model the said selected device as if it were a device of the first cluster, and the said device of the first cluster holding the stored representation may suitably be that device of the first cluster to which the data channel is connected. The said data channel may be a wireless link.
In accordance with a further aspect of the present invention, there is provided a communications device having the technical features of a cluster-connected device in a system as recited above.
BRIEF DESCRIPTION OF THE DRAWING
Further features and advantages of the present invention will become apparent from reading of the description of preferred embodiments of the invention, given by way of example only and with reference to the accompanying drawings, in which:
FIG. 1 represents an arrangement of devices forming three linked clusters;
FIG. 2 shows a pair of clusters using a different interconnect mechanism to the arrangement of FIG. 1 ;
FIG. 3 shows three clusters using a still further interconnect mechanism different to the arrangements of either FIG. 1 or FIG. 2 ; and
FIG. 4 schematically represents an arrangement for the handling of timing issues over the bridge in any of FIGS. 1 to 3 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A first arrangement of interconnected devices is shown in FIG. 1 , with the devices being divided into three clusters 10 , 20 , 30 , each based around a respective bus 18 , 28 , 38 supporting communication in accordance with IEEE Standard 1394 connect and communications protocols. In the following examples, reference is made to various communications protocols including IEEE 1394, IEEE 802.11, and HAVi (the Home Audio/Video interoperability standard based around 1394), and the disclosure of the specification of these various protocols is incorporated herein by reference. As will be recognised by the skilled reader, however, conformance with such protocols is not essential to the operation of the present invention.
The devices in the first cluster 10 comprise a set-top box (STB) 11 , a first digital video recorder (DVHS- 1 ) 12 , a digital versatile disc (DVD) player 13 and an RF send and receive unit 19 which acts as a gateway device for the first cluster. The devices in the second cluster 20 comprise a first television set (TV- 1 ) 21 , a second digital video recorder (DVHS- 2 ) 22 and an RF send and receive unit 29 which acts as a gateway device for the second cluster. The devices in the third cluster 30 comprise a second television set (TV- 2 ) 31 , a third digital video recorder (DVHS- 3 ) 32 , and an RF send and receive unit 39 which acts as a gateway device for the third cluster.
The second and third clusters 20 , 30 communicate with the first 10 via respective RF links 41 , 42 between the gateway devices at data rates which may be up to 8 Mbit/sec or even higher. At these rates, digital video transmitted from one cluster to another may be compressed according to the known MPEG standards. HAVi commands may also be exchanged between the clusters as indicated by arrows 17 , 27 , 37 : note that the channel for these commands may be integrated with the RF channel or it may be separate.
In the system of FIG. 1 , the main value of the cordless link is for presentation, namely getting content from a source (such as the STB 11 in the first cluster) to the point of consumption (e.g. the TV- 1 in the second cluster). This is particularly relevant where the source is tethered to a delivery medium, such as cable, terrestrial/satellite antenna, phone line, etc. From a logical point of view, the gateways and RF links may be treated as a single device 40 (as indicated by the dashed outline) such that the system as a whole then comprises just 1394-linked devices, although different timing issues on either side of the bridge “device” 40 will need to be addressed, as will be described in further detail below.
A handheld PIA-like unit may be used for TV viewing although this is not necessarily of value since most rooms will have a TV anyway. PIA units have compelling value for Internet Surfing and home control, however, and they also are useful for supporting interactive TV (e.g. background information to advertisements, TV shows, etc.).
For true mobility within the home, (e.g. using a PIA-type unit) the TV picture should be stable when stationary; however, when moving some flutter is probably acceptable, and this is achievable using the high frequency RF link and MPEG compression.
In such systems, related issues include the need to protect the cordless signal from casual eavesdropping, particularly for pay-per-view content; a need to support interactive services (e.g. based on Java, MHEG); and a need to retain synchronisation between audio and video—for example, if these components are sent via separate routes.
In connection with access to the MPEG stream, some STB designs may decode right down to YC/CVBS/RGB allowing no access to the MPEG stream itself, whilst support for 1394/HAVi presumes that products are 1394/HAVi equipped which may not always be the case.
Considering the RF related issues, and beginning with those relating to MPEG streaming, for correct timing of audio and video, the MPEG 90 kHz reference clock needs to be conveyed to the receiver via the RF channel. In order to broadcast to several receivers, there is no problem if all the receivers are on the same 1394 bus (i.e. in the same cluster) but where there are several clusters, it is recommended to use a dedicated MPEG stream to each, although the gateway device for the cluster sending out the MPEG streams (the source 1394 cordless AV adapter node CAVa) has to be able to configure this streaming.
In terms of presentation issues, to protect against possible errors caused by the radio channel, duplicate MPEG streams may be sent. To protect against possible delay caused by the radio channel the content could be ‘pushed’ at a “faster than realtime” rate to temporary storage at the receive side. It is noted that DVD has the unique issue of high bandwidth graphic overlay which demands massive radio bandwidth for real-time transfer—this issue is beyond the scope of the present application, however.
In terms of recording or archiving, the streaming may be given a lower priority for the radio bandwidth, assuming sufficient ‘spooling’ storage is available on the sending side of the link (this helps with bandwidth management). To ensure a robust result, improved error protection may also be used (e.g. full acknowledged packet transfer).
Products will not generally be isolated—they will be part of a wired 1394 cluster (even if only consisting of 2 products/devices); however, the basic requirement of presentation is to communicate from one product to another, either within the same 1394 cluster, or between clusters. It is not a necessary requirement that clusters need to communicate one to another at the 1394 level.
In terms of alternative solutions to the problems of interconnection, FIG. 1 represents a cordless MPEG link approach. Assuming presentation is the major requirement; this could imply simple one directional MPEG streaming from source to sink (left to right, or right to left, in the Figure). The approach keeps the 1394 buses (clusters) entirely separate, that is to say without requiring communications over the RF link to be 1394 compliant. The receive side must have the ability to control the signal originating devices (sources) within the 1394 cluster on the send side.
The gateway (1394 CAVa) is a special HAVi Full AV controller (FAV) device. The 1394 CAVa hosts Device Control Modules (DCM's) of devices located on remote 1394 buses (if necessary, more than one bus can be linked to, for multicast purposes). This implies that, in general, all devices that are hosted will have uploadable DCM's. In FIG. 1 , this is illustrated by the shaded boxes attached to each gateway device: in these shaded boxes are the “proxy” DCM's of selected products located within remote clusters. The communication of HAVi commands across the radio link can be performed in any way, including proprietary methods. AV stream routing (e.g. MPEG) may be done using ‘virtual 1394 plugs’ which would be coordinated with the RF addressing to direct the stream to the correct target 1394 cluster. In one variant, one or a set of standardised or common DCM's may be already present on the bridge. For example, a generic AV/C DCM could be included in the bridge to control AV/C devices, or a manufacturer could provide built-in DCM's for some of their own products.
An alternative arrangement of interconnected clusters is shown in FIG. 2 . The first cluster 50 comprises a STB 52 linked to a gateway device 59 by 1394 bus 58 . Instead of RF transmission by the gateway 59 , the first cluster includes a personal computer (PC) 54 or similar device which receives the MPEG from the gateway 59 as well as the HAVi commands 57 to go to a remote cluster.
The second cluster 60 comprises a digital TV/VCR unit 62 linked to a gateway device 69 via 1394 bus 68 . As for the first cluster, a PC 64 is connected to the gateway 69 which receives MPEG from the PC 64 , as well as the HAVi commands 65 from the first cluster 50 . In this example, communication of MPEG and the HAVi commands is accomplished between the PC's 54 , 64 via wireless link following IEEE 802.11 WLAN standards with each PC including an RF ISA/PCI card. Available cordless data links following these standards include Diamond HomeFree (which has a data rate of 1 Mbps) and RadioLan (10 Mbps).
In general, such an arrangement is less favoured than that of FIG. 1 in that a certain amount of buffering is liable to be required at the send and/or receive sides, although this can simply be provided by the PC's. The arrangement does have benefit, however, in that it can accommodate devices unsuited for connection to the 1394 bus of a cluster: in FIG. 2 this is illustrated by analogue TV/VCR 67 adjacent the second cluster which is supplied with images from an MPEG decoder 66 fed directly from the PC 64 of the cluster.
A further interconnect arrangement is shown in FIG. 3 and comprises three clusters 70 , 80 , 90 each having a respective cordless bridge CB device as gateway device 71 , 81 , 91 . In this example, the bridging between the clusters is by full cordless communications and at data rates determined by the cordless protocols used.
A problem that can arise with sending streams over 1394 bridges is how to handle the 1394-level timestamps present in many of the streaming formats. These are required because packet delivery is time critical for some formats, including MPEG. Buses on 1394 have a bus-wide clock such that, for timestamps generated on one bus to be valid on another, the clocks of the two buses must somehow be synchronised which, the skilled reader will recognise, is not always a simple matter. In addition, timestamps within transmitted data packets may need modification or adjustment by the bridge to take account of generally longer delivery times to devices on the far side of the bridge than to devices on the data originating bus.
In order to avoid such problems, a system as shown in FIG. 4 is suitably employed, with the 1394 buses 100 , 110 on either side of the bridge 120 . At point a, packets from the 1394 bus 100 are encoded and timestamped as specified in a further standard, IEC61883.
At point b, all the packets have passed through an interface chip or circuit assembly PHY 102 acting as interface to the 1394 physical layer, and through a link chip or circuit AVLINK 104 which implements IEC61883 for the relevant streaming format: an example of this chip is the Philips PDI1394L11. At b, the packets have had all 1394/61883 timestamps removed. Packets are released from the AVLINK chip 104 at the correct times, such that the timing information is now embodied by the release times of the packets themselves. In the following, we assume a packet is released at time t.
The next step is the sending of the packet across the bridge 120 : the only requirement of the bridge system is that it delivers the packet with a constant delay, referred to herein as T. How the bridge achieves this constancy is beyond the scope of the present invention: what matters is that a packet can be relied upon to arrive at a further AVLINK chip 114 on the other side of the bridge at time=t+T.
At point c, packets arrive at the “correct” time due to the constant delay T, and the AVLINK chip will now encode and timestamp them in conventional fashion, as dictated by IEC61883. These timestamps will be in the context of the second bus 110 . If it is determined that packets have been lost or corrupted by the bridge 120 , it is here at c, between the bridge and AVLINK 114 that recovery actions should be initiated.
From point d, having been passed through a further physical layer PHY interface 112 , the packets are sent out over the second bus 110 with timestamps appropriate for that bus.
To send digital video (DV) streams, there are some different requirements, largely due to the fact that DV is slightly less time-critical on delivery than MPEG, and a slightly different mechanism is used, based around the SYT timestamp as also specified in IEC61883. This allows for a stream to be sent with an “attached” clock signal, which can be up to 8 kHz. To send this, a clock signal with a frequency≦8 kHz is input to the AVLINK chip on the transmitting node. Every clock cycle (every “tick”), the value of the bus clock at that instant will be sampled, a constant value will be added to compensate for the transport delay, and transmitted over the bridge as part of the stream. The receiving node will store the value until such time as its own clock is equal to that value, and then output a tick. The 8 kHz limit is imposed as only one SYT timestamp can be sent per 1394 isochronous packet, of which there are 8000 per second.
As before, the physical means of transportation for this clock signal across the bridge will depend on the construction of the bridge itself. The same principle of taking the output from the receiving AVLINK chip on the first bus will mean that no timestamps in the context of the first bus appear on the second bus; the clock signal is just sent over the bridge to be re-timestamped to the context of the second bus.
In the interconnect arrangements described, a number of improvements are provided, the first of which may be described as the provision of mobile DCM's—that is to say DCM's crossing from one cluster to another. HAVi describes the Device Control Module (DCM) software which represents (or is an abstraction of) the control system of a physical device. This software can be run on another device that is capable of running such software. For instance, the DCM for a D-VHS recorder can be run on a Set Top Box. Currently, HAVi assumes that all devices in the network are connected on one single bus. The present invention extends this by providing for the DCM's to cross over the bridge. By having a representation of the remote device on the near side of the bridge, bridging problems can be greatly simplified as the remote device is apparently now on the near side of the bridge. In other words, there is provided software on one side of a bridge between buses which represents a device on another bus which is connected to another portal of the bridge.
A further improvement relates to the usage of so-called Legacy devices within the HAVi V1.0 specification. Legacy AV devices (LAV's) are already defined in HAVi and allow non-HAVi devices to be accessed and controlled by a HAVi network, by the use of DCM's (mentioned above). In effect, the DCM for a Legacy device is a bridge between a HAVi network and the native control of the Legacy Device (e.g. the above-mentioned D2B protocols). In this way, non-HAVi devices can be made to appear like a HAVi device on the HAVi network. This idea extends this mechanism to allow control of real HAVi devices on the far side of a bridge via the representation of that device on the near side of the bridge.
A still further improvement relates to the modification of Virtual plug parameters. HAVi already describes the capabilities of a connection by assigning, parameters to “virtual plugs” situated at each end of the connection path. In a bridge, parameters such as bandwidth are limited and are less than the capabilities of the actual physical device. The modification allows the representation of a remote device on the near side of the bridge to be modified to make allowances for the limitations of the bridge transport medium (e.g. RF).
From reading the present disclosure, other modifications and variations will be apparent to persons skilled in the art, including equivalents and features which are already known in the field of bus-connected and cordless communication systems and components and which may be used instead of or in addition to features already disclosed herein. | A local communication system comprises a first cluster ( 10 ) of devices interconnected for the communication of messages via a first data bus ( 18 ) and in accordance with a first set of communication protocols, a second cluster ( 20 ) interconnected via a second data bus ( 28 ) and following the first set of communication protocols; and a data channel ( 41 ) linking a device ( 19 ) of the first cluster ( 10 ) and a device ( 29 ) of the second cluster ( 20 ). The data channel ( 41 ) suitably comprises an RF link supporting communication of messages in accordance with a second set of communications protocols. A device ( 19 ) of the first cluster ( 10 ) holds a stored software representation of operational features of a selected device (DVHS- 2 ) of the second cluster ( 20 ) and any device ( 11 ) of the first cluster wishing to interact with said selected device (DVHS- 2; 22 ) instead interacts with said stored representation. | 7 |
This patent application is a divisional application of U.S. patent application Ser. No. 09/726,950, filed Nov. 30, 2000 now U.S. Pat. No. 6,488,155, which in turn is a divisional application of Ser. No. 09/379,062, filed Aug. 23, 1999, now U.S. Patent No.: 6,296,189 B1, issued on Oct. 2, 2001. Priority is herewith claimed under 35 U.S.C. §119(e) from copending Provisional Patent Application 60/097,906, filed Aug. 26, 1998, entitled “Multi-Spectral Imaging”, by John Moon. Priority is herewith also claimed under 35 U.S.C. §119(e) from copending Provisional Patent Application 60/140,567, filed Jun. 23, 1999, entitled “System for Remote Identification and Sorting of Articles”, by John Moon et al. The disclosure of each of these Provisional Patent Applications is incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
This invention relates to systems and methods for marking and coding objects and, more particularly, to systems and methods for optically coding objects such as textiles, linens, garments, documents and packages.
BACKGROUND OF THE INVENTION
A class of industrial problems exists in which a large number of items must be separated, identified, counted and sorted. One example is the textile service industry, wherein soiled garments or linens are returned in large unsorted groups for cleaning and sorting. Present day means for solving this problem cover a broad spectrum. One solution uses manual workers who sequentially sort amongst the many items, picking single items manually and identifying the items visually. This solution is unsatisfactory because it is both slow and expensive, due to the high reliance on manual labor.
There are also numerous coding and sorting applications in the multi-billion dollar textile services industry whose requirements are not efficiently met by bar codes or radio frequency identification (RFID). A particularly challenging problem is the sorting of flat goods such as napkins, tablecloths, towels and bed linen items. These items, which range in size from very small to large, are presented in distorted orientations and undergo severe washing and ironing cycles. These are just some of the technology barriers to accurate machine identification and automated counting and sorting of flat goods and bulk garments. The lack of a viable coding and sorting solution for this segment of the textile services industry has resulted in high labor costs, lack of stock control, and reduced profits.
Thus, a technique that provides for the machine readable marking of rental textiles is important for inventory control at commercial laundries and other installations where large quantities of similar-looking materials must be handled in a high speed manner. Currently, only a small fraction of the rental textile industry uses machine readable coding. Most coding currently used to uniquely identify a rental textile item is simply text printed on a heat-sealed label attached to the item, and requires the presence of a human operator.
There are several reasons why the textile rental industry has only slowly adopted machine readable identification technology. Historically, the only available machine readable marking schemes for textiles were bar-codes and radio-frequency ID (RFID). Bar codes are the most commonly available type of machine readable marking in use today. However, tests of identification systems in actual laundries have shown that bar coding is not a robust coding technology on textile items. Bar codes are highly susceptible to degradation through both soiling and wear. Furthermore, due to the precise spatial information required for a bar code (line width and spacing), any warping of the label (almost assured on a fabric substrate) can result in high reading error rates. Finally, bar codes require line-of-sight and (generally) a specific orientation with respect to the detector, both of which are difficult conditions to satisfy under typical large scale laundry conditions.
In contrast, the radio-frequency ID technique does not suffer from the line of sight and soiling problems associated with bar codes. However, RFID remains expensive, both from initial cost and associated maintenance costs, and therefore is normally not economical for the rental textile industry. Furthermore, RFID tags have a tendency to exhibit cross-talk when they are in proximity to one another, which can preclude their use on closely-spaced sorting conveyors.
It can be appreciated that a need exists for a technology that has the ease of use and the low cost associated with bar codes, and yet is more robust and tolerant of the conditions found in large scale commercial laundries and other similar environments, such as large scale document and package handling facilities.
In U.S. Pat. No.: 5,881,886 “Optically-Based Methods and Apparatus for Sorting Garments and Other Textiles” one of the inventors of this patent application has described various methods and apparatus that also address the problems referred to above.
OBJECTS AND ADVANTAGES OF THE INVENTION
It is a first object and advantage of this invention to provide an improved optically based system and method for encoding information onto objects, and for subsequently sorting or otherwise processing the objects using the encoded information.
It is a further object and advantage to provide a photonically encoded label wherein information concerning an object is encoded in both the spatial and wavelength domains.
SUMMARY OF THE INVENTION
The foregoing and other problems are overcome and the objects of the invention are realized by methods and apparatus in accordance with embodiments of this invention.
The teachings of this invention provide embodiments of a Multi-Spectral Imager and the application of same for the marking and coding of, for example, textiles, linens, garments, documents and packages for high-speed machine identification and sortation. Specific uses include, but are not limited to, garment and textile rental operations, laundry operations, and the postal and mail sortation of documents and packages.
The teachings of this invention are directed towards providing methods and apparatus that are used to identify items via information encoded within an applied mark, as well as a novel mark reading/decoding scheme. The teachings of this invention are multi-faceted, and encompass a method of printing fluorescent marks on an item, such as a heat-sealable label, to generate a unique identification number or indicia, as well as a reader system for reading applied marks. The reader system includes an illumination source that excites the fluorescent marks in combination with a color sensitive device, such as a camera, which is “blind” to the illumination wavelength but which can discern the fluorescence color and a relative spatial order of the fluorescent marks.
A method is disclosed for encoding information onto an article, and includes steps of (a) expressing the information as a multi-digit number; and (b) encoding the number as a plurality of regions that are disposed in a predetermined linear sequence. Each region emits one of a plurality of predetermined wavelengths comprising a set of wavelengths. A further step applies the plurality of regions to the article by printing the plurality of regions onto a label using a plurality of different fluorescent inks, and then affixing the label to the article, such as by a thermal process.
To readout the encoded information, the method further includes steps of (c) illuminating the plurality of regions with excitation light; (d) detecting a plurality of resulting wavelength emissions from the plurality of regions; and (e) decoding the number from the plurality of resulting wavelength emissions and their location in the linear sequence.
The article can be identified from the decoded number, and a future path that the article takes can be controlled based on the decoded number. As an example, a controller can select a type of washing that the article will receive, and/or a storage location for the article can be determined, based on the decoded number.
BRIEF DESCRIPTION OF THE DRAWINGS
The above set forth and other features of the invention are made more apparent in the ensuing Detailed Description of the Invention when read in conjunction with the attached Drawings, wherein:
FIG. 1 is a top view of an exemplary embodiment of a label having a plurality of different fluorescent bar-shaped regions arranged in a predetermined linear sequence for encoding information about an article to which the label will be affixed;
FIG. 2 is a block diagram of a multi-spectral imager system in accordance with this invention;
FIG. 3 is a block diagram of one embodiment of a color sensitive camera found in the system of FIG. 2;
FIG. 4 is a graph illustrating exemplary optical filter responses and fluorescence data;
FIG. 5 is a graph illustrating exemplary spectral data for each image pixel that detects with a green, yellow or red bar on the label shown in FIG. 1;
FIG. 6 is a logic flow diagram of an image processing method in accordance with this invention;
FIG. 7 is a block diagram of an exemplary commercial textile/garment sorting, washing and storage system that is constructed and operated in accordance with embodiments of this invention; and
FIG. 8 depicts an alternative embodiment of a multispectral imaging system for reading the label in FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
A description is first made of the coding technique in accordance with this invention. FIG. 1 depicts a preferred embodiment of a marking for a textile rental application. In one embodiment a plurality of fluorescent bands are applied using a standard impact printing technology. In other embodiments the plurality of fluorescent bands are applied using, for example, ink jet printing, screening, sublimation, or stamping. As such, any number of techniques for applying the marks can be used, and as employed herein such techniques are generally referred to as “printing”.
In general, the applied photonic ink is comprised of plastic fluorescent pigment and a standard phthalate ester plasticizer carrier. In a presently preferred embodiment of a formulation for a fluorescent impact printing ink, the preferred impact ink formula is 40 g/100 ml of fluorescent pigment/phthalate plasticizer. The phthalate plasticizer is preferably diisononyl phthalate. Other combinations of phthalate plasticizers, such as dioctyl, dibutyl, diethyl, etc. phthalate may be used as well. The only requirement is that the resulting phthalate ester/pigment combination does not soften the plastic cartridge that contains the nylon impact printing ribbon. The presently preferred fluorescent pigment is a finely-ground thermoset plastic resin which contains a selected fluorescent dye (such as one of the rhodamines) cross-linked into the matrix. Other embodiments include organic or inorganic phosphorescent and fluorescent pigments that are not significantly degraded by an industrial laundering process.
The selected inks can be applied with standard commercial dot matrix print cartridges, wherein each cartridge may hold, for example, three distinct optically active inks (e.g., red, yellow, green), and (optionally) a conventional black ink for printing operator-readable information. The labels 1 can be printed on durable thermal seal stock 2 and attached with standard heat seal equipment. A conventional printer 4 is shown in FIG.7 for printing the labels 1 , using a cartridge 5 that holds, for example, red, yellow and green fluorescent inks in accordance with this invention. In practice, the printer is driven by a suitable computer (not shown) having a program for generating numerical codes based on a desired coding technique (e.g., large napkins are assigned one group of numbers, small napkins another, etc.), and another or the same program for converting the generated number into a linear sequence of distinct wavelengths to be applied as fluorescent inks by the printer 4 .
In other embodiments the fluorescent bars 3 can be applied directly to the textile, linen or garment, or applied to a preexisting label on the textile, linen or garment, or applied to a removable (and possibly reusable) tag, or applied in any way that is suitable for the intended purpose of identifying, sorting and controlling the handling of the textiles, linens or garments.
In further embodiments the foregoing teachings are applied as well to other objects to be identified and sorted, including, by example, mail pieces, packages, documents, financial instruments, boxes containing various types of goods, etc.
In the example of FIG. 1 a label 1 is comprised of a suitable label stock substrate 2 having a plurality (e.g., 16) vertical fluorescent bars 3 applied thereto. In this example three different fluorescent colors are used: green (G), yellow (Y) and red (R). Each color is assigned to a number. For example, green=1, yellow=2, and red=3. A code is formed by reading fluorescent colors from left to right as, for example, (green) (yellow) (yellow)=122 (base3). The number of possible combinations for a given number of fluorescent marks n in therefore 3 n . Thus, for three fluorescent colors and thirteen of the bars 3 , the number of possible combinations is approximately 1.6 million.
The example label 1 has 16 bars. Assuming a code based on 13 bars, this leaves three bars for error correction purposes. The bars on either end can be reserved for checking the orientation of the label (so that the code is always reconstructed starting with the green bar and ending with the yellow bar.) Also, any label that does not have a green bar on one end and yellow bar on the other end can be immediately rejected. Furthermore, one or many bars may be reserved for a modulo-M division check of the decoded word. This represents another level of error correction which can be built into the code. Many other error correction schemes can be used as well, as should occur to those skilled in the art.
It should be noted that this coding scheme preferably uses a fixed, pre-determined number of bars. The codes are not weighted by the presence or absence (i.e. binary weighting) of a bar in any particular position. All bars must be present in order to have a successful decode. This is in contrast to a standard fluorescent bar code, which uses a single fluorescent color and then determines the bit value, not by fluorescence color, but by the distance between the presence or absence of a color.
The pattern of bars can be read in either direction (e.g., forward starting from a green bar and ending with a yellow bar, or reverse starting with yellow and ending with green), and the resulting code simply reversed if it is determined from the first bar read that the pattern of bars 3 was read in the reverse direction.
This aspect of the invention thus provides a method for encoding information onto articles, and includes steps of expressing the information as a multi-digit number; and encoding the number as a plurality of regions (e.g., the bars 3 ) that are disposed in a predetermined linear sequence, wherein each region emits one of a plurality of predetermined wavelengths comprising a set of wavelengths.
It should be noted that the label 1 can be coated after printing and thermal application to a garment or textile of interest. For example, an ultra-violet (UV) radiation curable clear coating may be applied to the label 1 , at least so as to cover the plurality of regions or the bars 3 , after printing and possibly heat sealing the label. The clear coating beneficially improves the wash characteristics. An example of such a coating resin is CraigCoat 1081R, which is available from Craig Adhesives.
A preferred embodiment of a multi-spectral imager, also referred to as a reader system 10 , is shown in FIG. 2 . The reader system 10 includes three major components, which are an illumination unit or source 12 to excite the fluorescence found in the bars 3 on the label 1 , a synchronized color sensitive imaging system 14 to obtain image data that includes the label 1 , and a digital image processing unit 16 for processing the image data.
To read the label 1 the reader system 10 operates as follows. First, the illumination source 12 is activated. The illumination source 12 may comprise, by example, a Xenon flash-lamp with a short-pass filter, or a light-emitting diode, or a laser, or an incandescent bulb, or even appropriately filtered sunlight. The output light excites the fluorescent bars 3 in the label 1 , and the fluorescent emissions are detected by the color sensitive camera unit 14 .
An example of a suitable color imaging system for the camera 14 is shown in FIG. 3. A plurality of beam splitters, such as a 30% beam splitter (30-BS) and a 50% beam splitter (50-BS) divide the fluorescence arriving from the label 1 into a plurality of color channels, each of which contains a color-selective imager. In the illustrated embodiment individual ones of three cameras 14 A, 14 B and 14 C have a different filter 15 A, 15 B and 15 C, respectively, over the detector element (DE) such that the illumination wavelength is blocked and the fluorescent color bands are let through, by varying amounts depending on the fluorescence color, onto the detector element. The light impinging on the detector element (DE) can be focussed by an imaging lens (IL).
In this example the camera unit 14 includes the three separate CCD arrays 14 A- 14 C, each with a different long-pass filter 15 A- 15 C. Long-pass filters are preferred because they are significantly less expensive than band-pass filters, and have other advantages which are detailed below in the decoding algorithm. However, band-pass and other types of filters can be used as well.
In general, the reader 14 may comprise a color sensitive CCD camera, a color sensitive CMOS camera, or a combination of two or more grayscale cameras with appropriate filters. The preferred data format from a color sensitive camera is YUV, since this format allows fast separation of the luma component and, therefore, fast spatial location of the imaged fluorescent marks or bars 3 .
Assume, for example, the long-pass filter responses shown in FIG. 4 (OG530, OG550 and RG610 are specific long-pass filter types, wherein the number designates the wavelength where 50% transmission occurs), and also assume the exemplary fluorescence signals for R, G and Y. Then, the spectral data shown in FIG. 5 (having three points for each pixel) can be decoded by, for example, a radial-basis-function neural network, or some other type of suitable decoder, as will be discussed in further detail below.
The teachings of this invention provide a number of advantages and novel features. First, only the spatial order of the bars 3 is relevant for decoding the label 1 . Since the actual spatial position is not important, distortions of the label 1 due to wrinkling of the fabric, etc., does not change the decoded output.
Second, since the cameras 14 A- 14 C can be looking in color bands that naturally show a low background fluorescence (unlike the case where ultraviolet illumination is used) only the code itself appears in the field of view of the camera. This allows for a much faster location of the bar image within an acquired image.
Third, even those codes represented by very faded bars 3 can still be successfully read by increasing the illumination power of source 12 and/or the gain (sensitivity) of the cameras 14 A- 14 C.
In order to successfully read a code from a label 1 the image processing software that executes in the digital image processing unit 16 (FIG. 2) performs the following tasks, in a preferred embodiment, in near-real-time. Reference is also made to the logic flow diagram of FIG. 6
At Block A the image processing software locates and orients the code (encoded region) in the image. At Block B the algorithm locates and separates all of the bar images, that is, the algorithm identifies and separate one from another individual ones of the sub-regions within the encoded region. At Block C the method determines the emission wavelength or color of each bar 3 , and at Block D, from the list of colors and the spatial order of the bars 3 , the algorithm decodes the information that was previously encoded into the encoded region of the label 1 . The execution of Block D is straightforward, once Blocks A-C have been successfully executed.
The first step (Block A) is preferably performed using a center-of-mass and eccentricity algorithm. Since the code appears in the image as a long rectangle, the label 1 can be located and oriented by first finding the center of mass of pixels above a certain threshold, and then by finding the orientation of the major axis around that center of mass. This allows multiple line scans to be taken of the pixel data across the bars in the direction of the major axis. A more sophisticated algorithm outlines and separates all bright areas appearing in the image, so that the need for the label to show all bars across a single line scan is eliminated. In this case dots or any other shape could be used for each fluorescent mark, thereby eliminating the use of the bars 3 .
It should be noted that there is one important detail of the optical system that greatly simplifies the steps shown in Blocks A and B. That is, since the preferred type of filters 15 A- 15 C are long-pass filters, the data in the shortest pass filter all look equally bright, i.e. the image appears to be an equalized gray-scale image, no matter what the fluorescence color of the each bar 3 happens to be. This would not be the case if band-pass filters were used. It is much simpler to locate and orient the code in this type of image, since one need not be concerned (at this stage) with the color information.
The use of long-pass filters, rather than band-pass filters, has a further advantage in the assembly of a multi-camera unit. If band-pass filters were used, the gray-scale image needed for code location and orientation would need to be synthesized from all three images, without a prior knowledge of where the code actually is in the field of view. If the synthetic color image is not perfectly registered in the space between arrays, the bars may not overlap one another and, therefore, can give false color information in the decoding step. If all bars can be precisely located in space, however, from one of the long pass images regardless of color, the need for perfect registration between arrays is relaxed. The precise location of a bar is recorded in the first image and then the brightest part of that bar can be found in successively filtered images using a very simple search procedure limited to a few pixels. This means that the mis-registration of the arrays can be corrected in software, and furthermore removes the need for micron-scale adjustment of the position and focusing of the arrays during the assembly step.
Once the line data containing the peak positions of the data (corresponding to each bar 3 ) is located, the spatial position of each peak is discovered (Block B). The peak finding algorithm is preferably based on a pattern recognition algorithm which looks for a characteristic four-point signature at the inflection points of the smoothed data. The peaks are decoded and then sorted according to which peaks appear most like a typical bar (which can be previously determined off-line). The first n highest-scoring peaks are then retained, where n is the number of bars one expects to see (e.g., 16). If less than n bars are found in the image, an error condition is indicated.
Finally, once the bars are located the color information of each bar is obtained (Block C). The color information contains, for an exemplary three color palette, three points per pixel. These three points are then run through a radial basis function neural network (which can be software running on the processing unit 16 ) to determine the color. The data in the pre-trained neural network is grouped, for example, according to number of wash cycles. This takes into account any overall data shift in the labels due to fading, etc.
Important features of the optically coded labels 1 include, for example: they can be thermally applied using heat seal backing (or simply stitched on as well), they exhibit a wash durability that may outlast the garment to which they are affixed, a high read accuracy (99%) is obtained, they also exhibit high readability under soiled conditions, and finally, reliable reads have been achieved at conveyor speeds of up to 10,000 items/hour.
Advantages of the optically coded labels include, for example, that they do not rely on a contrast-based technology, and soiling of the label has a greatly reduced effect on readability. Furthermore, since the coding is done spatially and by wavelength, the bar spacings and thicknesses on the label 1 have no impact on readability (unlike conventional bar codes), and the labels can be read in any orientation. Furthermore, since the labels can be read using a non-scanning technology, an exemplary 12 inch field of view of the color sensitive camera 14 allows greater latitude when the items are on hangers, which can exhibit swaying motions as then are conveyed past a camera unit 14 mounted next to the conveyor.
A code capacity of an exemplary multi-spectral imaging system operating in accordance with the present invention can be defined by the following:
Number of codes N C =T N , where
T=number of unique spectral signals (e.g., red, green, yellow), and
N=number of spatial positions.
As an example, for T=5 and N=10 (5 unique spectral signals in 10 positions), the total number of codes N C =10 8 .
Referring to FIG. 7, an identification and sorting system 20 in accordance with the present invention includes a master control unit or module 22 which is connected to one or more material transport unit modules, shown as a first classification conveyor module 24 and a second classification conveyor module 26 . Generally, the soiled unsorted linen and garment items are loaded by various means such as laundry chutes or conveyors (load stations 22 A and 22 B) into the master control module 22 . The soiled and unsorted items are then transported by the one or more conveyor modules 24 and 26 first to wash stations 24 A, 24 B, etc., via air jet sorting units 28 , and then to storage depository locations 26 A, 26 B, etc. The wash stations 24 A- 24 E may be segregated to wash appropriate wash classes of the linen and garment items. The storage depository locations 26 A- 26 E are segregated so that only a specific type of linen or garment item is stored at each location. The system 20 includes one or more of the above described multi-spectral imagers or reader systems 10 , as shown in FIG. 2, which are capable of high speed reading of labels 1 or similar tags or materials in the linen and garment items. The labels 1 and/or tags are encoded for identification purposes with the photonically active materials discussed above. The reader(s) 10 may be located in the classification conveyor modules 24 and 26 , or at an interface 23 between the master control module 22 and the classification conveyor modules 24 and 26 . The reader(s) 10 are connected to a central processor (OP) in the master control module 22 . The central processor uses data from the reader(s) 10 to control the classification conveyor modules 24 and 26 to automatically sort the linen and garment items for washing in the corresponding wash stations 24 A- 24 E, and then for storage in the appropriate storage location 26 A- 26 E. The system 20 can also optionally be operated with non-photonically coded inventory, such as by indicating with a switch closure to the master control module 22 that the conveyor(s) 24 , 26 are to be programmed for conventional manual classification. A hybrid system operation can also be employed, wherein, by example, the item classification is done manually, but inventory count and wash sorting is done using the information encoded in the labels 1 .
The linen and garment items used with the system 20 of the present invention include the labels 1 , threads or yarn with photonically active materials. The photonically active materials are encoded in the labels 1 , threads or yarn to identify the linen and garment items by, for example, wash type and storage category. The encoded wash types and categories are recognized by the central processing unit when read by a reader 10 in the system 20 .
The linen and garment items used with the system 20 of the present invention preferably employ the labels 1 which leverage the signal-to-noise advantages of light emission with the high code densities of bar coding. Each label 1 contains, as described above, a series of lines or bars 3 that emit one of several wavelengths to represent a unique number. Since the label 1 emits wavelengths of light, rather than reflecting incoming light, as with bar codes, they are highly tolerant of soiling and wash fading.
The photonically active labels 1 of this invention do not depend on the spacing and thickness of the printed lines or bars as is the case in bar code technology. The encoded information of the label 1 is contained in the wavelength domain, and in the spatial sequence of wavelengths. As a result, the labels 1 provide significantly more robust and simple code patterns than found in conventional bar coding techniques. This attribute allows the labels 1 to be read accurately in any orientation with severe bending, distortion, or other problems often encountered with garments in high production laundries. The photonically active labels 1 may also be read over a wider field of view (e.g., 20 cm by 15 cm) than bar codes, since the requirement to resolve narrow line features does not exist.
FIG. 8 illustrates a further embodiment of a multi-spectral reader system 10 A, wherein fluorescent yarn or fluorescent threads 3 A or the bars 3 are illuminated within an area 12 A by the excitation source 12 , and the resulting fluorescent emissions are collected by an imaging system 30 , passed through a slit 32 to a grating 34 or some other suitable wavelength resolving device, to produce a spectrum 36 . The spectrum 36 contains the encoded information from the threads 3 A or bars 3 , and the information is expressed as a function of both wavelength and position. The spectrum 36 could be converted to pixels by a two dimensional CCD detector or other suitable means, and the locations of the those pixels above a threshold value converted to the encoded information by using a suitably trained neural network or some other image processing technique.
Thus, while the invention has been particularly shown and described with respect to preferred embodiments thereof, it will be understood by those skilled in the art that changes in form and details may be made therein without departing from the scope and spirit of the invention. | A multi-spectral imager and the applications of same for the marking and coding of, for example, textiles, linens, garments, documents and packages for high-speed machine identification and sortation. Specific uses include garment and textile rental operations, laundry operations, and the postal and mail sortation of documents and packages. Methods and apparatus are provided to identify items via information encoded within an applied mark, as well as a novel mark reading/decoding scheme. A method is disclosed for printing fluorescent marks on an item, such as a heat-sealable label, to generate a unique identification number or indicia, as well as a reader system for reading applied marks. The reader system includes an illumination source that excites the fluorescent marks in combination with a color sensitive device, such as a camera, which is “blind” to the illumination wavelength but which can discern the fluorescence color and a relative spatial order of the fluorescent marks, wherein the information is encoded. | 8 |
BACKGROUND OF THE INVENTION
Pigment concentrates are produced by digesting pigments in a liquid carrier medium using shearing machines and thus finally dispersing them in such a way that the pigment is permanently present in the form of the primary particles. Suitable shearing machines are known to the expert and are described, for example, in
C. H. Hare, Protective Coatings—Fundamentals of Chemistry and Composition, Technology Publishing Comp., Pittsburgh (1994)
which is particularly concerned with American technologies. In view of the importance of dispersion to the lacquer, paint and printing ink industry, both the dispersion process and the low molecular weight and relatively high molecular weight compounds suitable for stabilizing the primary particles are described in detail in the specialist literature, cf. for example:
H. Kittel, Lehrbuch der Lacke und Beschichtungen, Vol. III, pages 239 et seq, Verl. W. A. Colomb, Berlin, Oberschwandorf (1976)
J. V. Robinson, R. N. Thompson, Dispersants, in Paper Coating Additives, Monograph No. 25, TAPPI, Atlanta 1963
J. D. Schofield, Polymeric Dispersants, in Handbook of Coating Additives, L. J. Calbo (Ed.), Vol. 2, Marcel Dekker, New York Basel, Hong Kong (1992).
There is no teaching to be derived from the known prior art on the choice of particular additives which effectively support the formulation of pigment concentrates, particularly where these pigment concentrates are intended to allow the production of low-emission or even emission-free paints and printing inks or when they are intended to be free from ecologically or ecotoxicologically unsafe substances.
One particular difficulty lies in the formulation of water-based pigment concentrates, particularly if no low molecular weight co-solvents, such as ethylene glycol or propylene glycol, are to be added. Thus, although so-called pigment dispersants based on polyphosphates or polyacrylates, as the expert well knows, are eminently suitable for keeping pigments and fillers suspended in emulsion paints in conjunction with the latex particles stabilized by emulsifiers or protective colloids, they are not suitable for the production of pigment concentrates with the requirement profile described above.
Most dispersants, which are perfectly suitable in organic carrier oils differing in polarity, fail when water is selected as the continuous phase for the pigment concentrates. Surfactant-based dispersants with a good wetting effect on pigments, such as alkylphenol polyglycol ethers (cf. for example GB 861 223) have recently entered the ecological debate so far as their biodegradability is concerned both in the detergent industry, where they have already been completely replaced as surfactants in Germany, and in emulsion polymerization processes, i.e. in the production of water-based binders for emulsion paints, cf.:
C. Baumann, D. Feustel, U. Held, R. Höfer, “Stabilisierungssysteme für die Herstellung von Polymer-Dispersionen”, in: Welt der Farben, pages 15 et seq. (February 1996)
Another complication affecting the choice of additives for the formulation of pigment concentrates is that the dispersing additive has to be selected so that, largely irrespective of the carrier oil, the viscosity of the continuous phase decreases with increasing shear force, i.e. must be pseudoplastic and definitely not dilatant.
Another factor which has to be taken into account in the formulation of pigment concentrates is that a special balance has to be established between water retention capacity and hygroscopicity so that the drying of the concentrate is significantly retarded. Partly dried pigment concentrates are intended to be readily redispersible. On the other hand, water retention capacity and hygroscopicity should not be so high that the final coating is sensitive to water.
Other performance properties of the final paint, such as stability to freezing/thawing, stability in storage, shear stability, should be as little affected in a negative sense as the properties of the cured film, for example transparency, gloss or resistance to blushing.
Another particular requirement to be satisfied by the pigment concentrates to be provided in accordance with the present invention is that they should be compatible with a broad range of binders, organic and inorganic pigments which, in turn, are mostly dispersed in so-called basic lacquers, and at the same time both with water and with the various solvents used in paints and with the highly alkaline waterglasses used in silicate paints.
On an industrial scale, a large percentage of liquid paints is produced by preparing the polymeric binder in a separate stage and then mixing it with the other constituents to form the final paint. If pigmenting is intended to be carried out at this early stage, the pigment is ground with the binder in a preliminary step carried out either in a high-speed mixer or in a dissolver and is then diluted down to the in-use concentration. DIY paints and paints for the professional decorator both for interior and exterior application are of particular interest in connection with the present invention. The binders for these paints are produced by emulsion polymerization in aqueous phase. In practice, the aqueous phase often contains volatile organic solvents, so-called coalescing agents, which are added either during the polymerization itself or at a later stage and which support film formation by partly dissolving the latex particles and promote levelling. The smell of these coalescing agents, particularly the known and widely used isobutyric acid-2,2,4-trimethyl-3-hydroxypentyl ester (Texanol®), remains noticeable for several days in freshly painted rooms. However, it is becoming increasingly more unacceptable in modern society. Accordingly, there is an interest in keeping modern paints completely free from such coalescing agents and other volatile solvents and co-solvents and in ensuring that they are not carried over into the paints by the pigment concentrates.
Besides the coloring of paints at the production stage, a significant percentage is only colored immediately before use either to establish special tones or to meet special customer requirements. In these cases, an industrially preformed pigment concentrate is added to and mixed with a white or pastel-colored stock paint. This customer-oriented method of coloring can be carried out both by hand and on a semi-industrial or full industrial scale. In cases such as these, the pigment concentrate is generally mixed in a ratio of 5 to 200 ml per l stock paint. A combination of two or three different pigment pastes is often needed to obtain the required color tone. The pigment concentrates usually contain high pigment concentrations, i.e. the pigment volume concentration (or PVC for short) is normally between 10 and 80%.
Ethylene oxide adducts with special glycols containing a —C≡C— group as structural element are known from DE-A-26 28 145. These compounds are said to be suitable as humectants, dispersants, nonionic antifoam agents and viscosity stabilizers and to develop their effect in aqueous solution in lower concentrations than conventional surfactants. Beyond listing the above-mentioned applications, however, DE-A-26 28 145 does not disclose any other concrete details or embodiments.
EP 565 709 B1 discloses water-based inkjet inks which contain polyol/alkylene oxide condensates as co-solvent. According to page 4, lines 9 to 15 of this document, the polyol contains in particular 3 or more OH groups. The polyols explicitly mentioned include in particular special triols, such as glycerol, trimethylol propane, trimethylol ethane, 1,2,4-butanetriol and 1,2,6-hexanetriol; tetrols, such as pentaerythritols and di(tri-methylol propane), pentols, such as glucose, and hexols such as sorbitol and inositol. However, the use of diols is described as unsatisfactory. In this connection, it has been found that alkylene oxide condensates of diols are generally not compatible with pigment dispersions with the possible exception of neopentyl glycol alkoxylates.
DE 195 11 669 A1 describes the use of dimerdiol alkoxylates as thickeners for water-based surface-active compositions, i.e. laundry detergents, dishwashing detergents and cleaners and also hair care and body care formulations.
WO 96/7689 discloses copolymers with the general formula (A—COO) 2 —B, where A has a molecular weight of at least 500 and is the residue of an oil-soluble complex monocarboxylic acid of special structure and B has a molecular weight of at least 500 and is the divalent residue of an alkyl glycol or a polyalkylene glycol. The copolymers according to WO 96/7689 are said to be suitable for dispersing inorganic pigments in organic media.
EP 735 109 A2 describes water-based pigment preparations which contain inter alia 10 to 80% of a pigment and 0.1 to 20% of an alkoxylation product obtained by addition of optionally substituted styrenes onto optionally substituted phenols and reaction with ethylene oxide and/or propylene oxide.
DE 39 20 130 A1 describes the use of partial esters of oligoglycerols with fatty acids as pigment dispersants for water-based lacquer dispersions. The partial esters mentioned may optionally be ethoxylated and/or propoxylated.
The problem addressed by the present invention was to provide effective additives for the production of pigment concentrates and the pigment concentrates obtainable with these additives which would meet the numerous criteria mentioned above in regard to the desirable property profile of such additives or the pigment concentrates themselves.
BRIEF SUMMARY OF THE INVENTION
The present invention includes the use of dimerdiolalkoxylates in the preparation of pigment concentrates, and includes methods of preparing the same. The present invention also includes pigment concentrates comprising a pigment, a dimerdiolalkoxylate in accordance with the present invention, and a liquid carrier medium. Pigment concentrates of the present invention are preferably aqueous, and thus, the preferred liquid carrier medium is water.
In a first embodiment, the present invention relates to the use of dimerdiol alkoxylates as additives for the production of pigment concentrates. Dimerdiol alkoxylates in the context of the present invention are understood to be products of the addition of 1 to 200 moles ethylene oxide and/or propylene oxide onto dimerdiols predominantly containing 36 to 44 carbon atoms.
Dimerdiols are well-known, commercially available compounds which are obtained, for example, by reduction of dimer fatty acid esters. The dimer fatty acids on which these dimer fatty acid esters are based are carboxylic acids which are obtainable by oligomerization of unsaturated carboxylic acids, generally fatty acids, such as oleic acid, linoleic acid, erucic acid and the like. The oligomerization is normally carried out at elevated temperature in the presence of a catalyst of, for example, clay. The substances obtained (dimer fatty acids of technical quality) are mixtures in which the dimerization products predominate. However, small percentages of higher oligomers, more particularly the trimer fatty acids, are also present. Dimer fatty acids are commercially available products and are offered in various compositions and qualities. Abundant literature is available on the subject of dimer fatty acids, of which the following articles are examples:
Fette & Öle 26 (1994), pages 47-51
Speciality Chemicals 1984 (May Number), pages 17, 18, 22-24
DETAILED DESCRIPTION OF THE INVENTION
The dimerdiols on which the dimerdiol alkoxylates to be used in accordance with the invention are based are well known among experts, cf. for example a fairly recent article which discusses inter alia the production, structure and chemistry of dimerdiols:
Fat Sci. Technol. 95 (1993) No. 3, pages 91-94
According to the invention, preferred dimerdiol alkoxylates are those which are derived from dimerdiols with a dimer content of at least 50% and, more particularly, 75% and in which the number of carbon atoms per dimer molecule is predominantly in the range from 36 to 44. Dimerdiol ethoxylates containing 1 to 30 moles ethylene oxide per mole dimerdiol are most particularly preferred.
In one preferred embodiment, the present invention relates to the use of dimerdiol alkoxylates as additives for the production of water-based pigment concentrates.
The quantity of dimerdiol alkoxylates to be used in accordance with the invention is determined on the one hand by the nature of the dyes to be dispersed and by the quantity of the dyes to be dispersed. The dimerdiol alkoxylates are preferably used in a quantity of 0.1 to 20% by weight, based on the pigment dispersion as a whole.
The production of the dimerdiol alkoxylates may be carried out by any of the methods known to the expert from the literature. In general, the required dimerdiol is alkoxylated by standard methods. The standard method of alkoxylation comprises contacting an alcohol (in the case of the present invention a dimerdiol) with ethylene oxide and/or propylene oxide and reacting the resulting mixture at temperatures of 20 to 200° C. in the presence of an alkaline catalyst. In this way, adducts of ethylene oxide (EO) and/or propylene oxide (PO) with the particular dimerdiol used are obtained. Accordingly, the addition products are EO adducts or PO adducts or EO/PO adducts with the particular dimerdiol used. In the case of the EO/PO adducts, the addition of EO and PO may be carried out statistically or in blocks.
The present invention also relates to pigment concentrates containing
a) 10 to 80% by weight of one or more pigments,
b) 0.1 to 20% by weight of one or more dimerdiol alkoxylates based on dimerdiols predominantly containing 36 to 44 carbon atoms, these compounds containing 1 to 200 moles ethylene oxide and/or propylene oxide per mole dimerdiol, and
c) 15 to 85% by weight of a liquid carrier medium.
The dimerdiol alkoxylates present in the pigment concentrates according to the invention are nitrogen-free and are free from hydrolyzable ester or aldehyde groups which is of particular advantage so far as the application in question here is concerned.
According to the invention, there are basically no restrictions on the choice of the pigments a). As known to the expert, pigments are particulate organic or inorganic materials which are substantially insoluble in solvents or binders and which can have either a coloring effect or a flatting/matting effect of their own. Many inorganic pigments also act as fillers and vice versa. Examples of particularly widely used classes of pigments can be found in the relevant literature, for example:
Otto-Albrecht Neumüller, Römpps Chemie-Lexikon, 7the Edition, Stuttgart 1974, pages 2693-2695.
The pigment concentrates according to the invention preferably contain compounds containing 1 to 30 moles ethylene oxide and/or propylene oxide per mole dimerdiol as the dimerdiol alkoxylates b).
Liquid carrier media c)—for example organic carrier oils or water—are known to the expert. In one preferred embodiment, water is used as the liquid carrier medium. In this case, the pigment concentrates are water-based.
In another embodiment, the pigment concentrates according to the invention additionally contain 0.1 to 30% by weight of one or more surfactants d) from the group of alkyl polyglycosides (as described in more detail hereinafter), fatty alcohol polyglycol ethers (as described in more detail hereinafter) and styryl phenol polyglycol ethers (as known for example from the above-cited EP-A-735 109) besides the compulsory components a), b) and c).
Alkyl polyglycosides may be characterized by general formula (IV):
R—(G) p (IV)
where R is a linear saturated alkyl chain containing 8 to 22 carbon atoms and (G) p is a glycoside or oligoglycoside unit with a degree of oligomerization x of 1 to 10, for deinking waste paper. Alkyl glycosides corresponding to general formula (IV) are very well-known surface-active agents which can be obtained by acetalization from sugars and aliphatic, primary alcohols containing 8 to 22 carbon atoms. A preferred sugar component (glycoses) is glucose although fructose, mannose, galactose, telose, gulose, allose, altrose, idose, arabinose, xylose, lyxose, libose and mixtures thereof may also be used. By virtue of their ready availability and their favorable performance properties, the acetalization products of glucose with fatty alcohols obtainable, for example, from natural fats and oils by known methods, more particularly with linear, primary, saturated and unsaturated C 8-22 fatty alcohols are preferably used. So far as the glycoside unit (G) p is concerned, both monoglycosides (p=1), where a sugar unit is attached to the fatty alcohol by a glycoside linkage, and oligomeric glycosides with a degree of oligomerization p of 2 to 10 are suitable. Mixtures of mono- and oligoglycosides are generally present. Alkyl glycosides (IV), where R is an alkyl containing 8 to 22 carbon atoms and (G) p is a glycoside or oligoglycoside unit with a degree of oligomerization p of 1 to 10, are particularly suitable. In one most particularly preferred embodiment, R is an alkyl group containing 8 to 14 carbon atoms. The average degree of oligomerization is preferably in the range from 1 to 1.5.
Fatty alcohol polyglycol ethers may be characterized by general formula (V):
R 9 —O—(CH 2 —CHR 10 —O) q H (V)
where R 9 is a linear saturated alkyl chain containing 8 to 22 carbon atoms, R 10 is hydrogen or a methyl group and the index q is a number of 1 to 50. Particularly preferred compounds (V) are fatty alcohol ethoxylates, more especially addition products of 2 to 20 moles ethylene oxide per mole fatty alcohol containing 12 to 18 carbon atoms.
In another embodiment, the pigment concentrates according to the invention additionally contain 0.1 to 30% by weight of one or more co-addicts e) from the group of polyethylene glycols and polyglycol ethers (obtainable by ethoxylation of 1,2- or 1,3-propanediol, 1,2- or 1,4-butane-diol, hexanediol, glycerol, trimethylol propane or pentaerythritol), these compounds having a molecular weight of 200 to 10,000 and preferably in the range from 200 to 600, in addition to the compulsory components a), b) and c).
The pigment concentrates according to the invention may additionally contain other ingredients typical of pigment concentrates in addition to the above-mentioned compulsory components a), b) and c). Examples of such ingredients are defoamers, preservatives, drying retarders and anti-settling agents.
The pigment concentrates according to the invention are suitable for coloring paints, for example by the amateur or by the professional in paint banks or even by the paint manufacturer. However, the pigment concentrates according to the invention may also be used for coloring other paints or coatings, such as printing inks, leather finishes, wall-covering paints, wood varnishes, wood protection systems and wood stains, overprinting lacquers or air- or oven-drying industrial lacquers, and for pigmenting colored pencils, fiber-tip pens, inkjet inks, Chinese inks, pastes for ballpoint pens, shoe care creams, nonwoven fabrics, paper coatings and paper stock, cardboard printing inks, dope dyes and films.
The following Examples are intended to illustrate the invention without limiting it in any way.
EXAMPLES
1. Substances Used
1.1. Pigments
Pr 101: Pigment with Colour Index PR (pigment red) 101; “Bayferrox 120 M” (Bayer AG) was used.
PV 19: Pigment with Colour Index PV (pigment violet) 19; “Hostaperm rotviolet ER 02” (Hoechst AG) was used.
PG 7: Pigment with Colour Index PG (pigment green) 7; (Sunfast grün 7 264-0414” (Sun Chemicals) was used.
PBk 7: Pigment with Colour Index PR (pigment black) 7; “Spezialschwarz 4” (Degussa AG) was used.
1.2. Anti-settling Agent
Xanthan gum “Deuteron VT 819” (Wilhelm O. C. Schöner GmbH, Achim)
1.3. Defoamer
Silicone defoamer “Dehydran 3282” (Henkel KGaA, Düsseldorf)
1.4. Additives According to the Invention
Add-1: Addition product of 10 moles of ethylene oxide onto 1 mole of a dimerdiol containing 36 to 44 carbon atoms
1.5. White Emulsion Paints or Lacquers
Disp-1: Emulsion paint based on vinyl acetate/ethylene copolymer (“Vinnapast EZ 36”, Wacker Chemie)
Disp-2: Emulsion paint based on styrene acrylate (“Acronal 290D”, BASF)
Disp-3: Emulsion lacquer based on pure acrylate (“Neocryl XK90”, Zeneca Resins, NL)
2. Preparation of the Pigment Pastes (Pigment Concentrates)
2.1. Example B-1
33.4 Parts by weight of water were initially introduced, 6.0 parts by weight of additive Add-1 were added with stirring and the resulting mixture was homogenized. 60 Parts by weight of pigment PR 101 were then added and the whole was homogenized using a dissolver (Dispermat CV, manufacturer: Getzmann, Reinhardshagen). Dimethyl ethanolamine was carefully added to the premix obtained in this way in such a quantity that a pH value of 8 was obtained. 0.4 Part by weight of the defoamer mentioned under No. 1.3. and 0.2 part by weight of the anti-settling agent mentioned under No. 1.2. were then added and the whole was dispersed for 30 minutes at 2000 r.p.m. using a stirrer-equipped ball mill operating on the circulation principle (Dispermat SL, manufacturer: Getzmann, Reinhardshagen).
2.2. Example B-2
54.6 Parts by weight of water were initially introduced, 15 parts by weight of additive Add-1 were added with stirring and the resulting mixture was homogenized. 30 Parts by weight of pigment PV 19 were then added and the whole was homogenized using a dissolver (Dispermat CV, manufacturer: Getzmann, Reinhardshagen). Dimethyl ethanolamine was carefully added to the premix obtained in this way in such a quantity that a pH value of 8 was obtained. 0.4 Part by weight of the defoamer mentioned under No. 1.3. was then added and the whole was dispersed for 60 minutes at 3500 r.p.m. using a stirrer-equipped ball mill operating on the circulation principle (Dispermat SL, manufacturer: Getzmann, Reinhardshagen).
2.3. Example B-3
48.6 Parts by weight of water were initially introduced, 11 parts by weight of additive Add-1 were added with stirring and the resulting mixture was homogenized. 40 Parts by weight of pigment PG 7 were then added and the whole was homogenized using a dissolver (Dispermat CV, manufacturer: Getzmann, Reinhardshagen). Dimethyl ethanolamine was carefully added to the premix obtained in this way in such a quantity that a pH value of 8 was obtained. 0.4 Part by weight of the defoamer mentioned under No. 1.3. was then added and the whole was dispersed for 60 minutes at 4000 r.p.m. using a stirrer-equipped ball mill operating on the circulation principle (Dispermat SL, manufacturer: Getzmann, Reinhardshagen).
2.4. Example B-4
58.6 Parts by weight of water were initially introduced, 16 parts by weight of additive Add-1 were added with stirring and the resulting mixture was homogenized. 25 Parts by weight of pigment PBk 7 were then added and the whole was homogenized using a dissolver (Dispermat CV, manufacturer: Getzmann, Reinhardshagen). Dimethyl ethanolamine was carefully added to the premix obtained in this way in such a quantity that a pH value of 8 was obtained. 0.4 Part by weight of the defoamer mentioned under No. 1.3. was then added and the whole was dispersed for 90 minutes at 4000 r.p.m. using a stirrer-equipped ball mill operating on the circulation principle (Dispermat SL, manufacturer: Getzmann, Reinhardshagen).
3. Performance Tests
The pigment pastes obtained in accordance with 2.1. to 2.4. (Examples B-1 to B4) were tested for their viscosity behavior and for their compatibility with white emulsion paints or lacquers. The results are set out in Tables 1 to 3.
3.1. Viscosity Behavior
The viscosities of the pigment pastes according to Examples B-1 to B-4 were measured at room temperature (Brookfield LVT, 30 r.p.m., spindle 2-4, after stirring for 1 minute)
a) after storage for 24 hours at 20° C. and
b) after storage for 4 weeks at 40° C.
The values in Table 1 are in mPas.
TABLE 1
Viscosity behavior
B-1
B-2
B-3
B-4
Viscosity after 24 hours
800
4200
300
150
Viscosity after 4 weeks
900
4400
310
180
3.2. Rubout
To determine rubout, quantities of 10% by weight (based on the white emulsion paint used or the emulsion lacquer used) of the pigment pastes of Examples B-1 to B-4 were added to and homogeneously mixed with the white emulsion paints or lacquers Disp-1 to Disp-3. The formulations obtained were then applied in a thin layer (150 micrometers wet layer thickness) to contrast paper cards (Erichson Type “7.32/7”)
a) immediately afterwards and
b) after storage for 4 weeks at 40° C.
After about 3 minutes, the mixture applied was rubbed with a finger in the lower third of the test card, after which the color tones of the unrubbed surface were compared with the color of the rubbed surface (using a Dr. Lange Microcolor to the CIELAB standard, light type D65, 10°). The resulting ΔE values are set out in Table 2a (formulations directly used) and 2b (formulations stored for 4 weeks). As the expert knows, ΔE values of 0.3 to 0.5 are regarded as very good in the specialist technical field in question here; ΔE values of 0.5 to about 1.2 are regarded as good while ΔE values above 1.0 are unacceptable.
TABLE 2a
Rubout data of directly used formulations
B-1
B-2
B-3
B-4
Disp-1
0.4
0.4
0.4
0.6
Disp-2
0.5
0.5
0.6
0.3
Disp-3
0.4
0.3
0.4
0.4
TABLE 2b
Rubout data of formulations stored for 4 weeks
B-1
B-2
B-3
B-4
Disp-1
0.5
0.4
0.6
0.6
Disp-2
0.4
0.5
0.5
0.4
Disp-3
0.5
0.4
0.4
0.5
3.3. Gloss
To determine gloss, quantities of 10% by weight (based on the white emulsion paint used or the emulsion lacquer used) of the pigment pastes according to Examples B-1 to B-4 or added to and homogeneously mixed with the white emulsion paints or lacquers Disp-1 to Disp-3. The formulations obtained were then applied in a thin layer (150 micrometers wet layer thickness) to contrast paper cards (Erichson Type “7.32/7”)
a) immediately afterwards and
b) after storage for 4 weeks at 40° C.
After drying, gloss was determined with a Dr. Lange gloss meter at angles of 85° and 60°. The results are set out in Tables 3a (formulations directly used) and 3b (formulations stored for 4 weeks).
The gloss of the white emulsion paints or lacquers, i.e. the unmodified polymer dispersions Disp-1 to Disp-3 not colored with pigment pastes B-1 to B-4 according to the invention, was also determined for comparison. These reference values are also included for comparison purposes in Tables 3a and 3b under the column heading “reference”.
TABLE 3a
Gloss data of directly used formulations
Measuring
angle
Reference
B-1
B-2
B-3
B-4
Disp-1
85°
3
3
3
3
3
Disp-2
85°
5
5
5
5
5
Disp-3
60°
44
44
46
46
44
TABLE 3b
Gloss data of formulations stored for 4 weeks
Measuring
angle
Reference
B-1
B-2
B-3
B-4
Disp-1
85°
3
3
3
3
3
Disp-2
85°
5
5
5
5
5
Disp-3
60°
45
46
46
47
45 | Pigment concentrates comprising a pigment, a liquid carrier medium and a dimerdiolalkoxylate, wherein a dimer portion of the dimerdiolalkoxylate comprises from about 36 to about 44 carbon atoms, and wherein the at least one dimerdiolalkoxylate has from about 1 to about 200 moles of alkylene oxide per mole of dimerdiol, are described in conjunction with methods of preparing the same. | 3 |
This is a divisional of application No. 07/935,876 filed Aug. 26, 1992.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a numerically controlled machine tool and especially to the tool feedrate control of a numerical control unit.
2. Description of the Background Art
A numerical control unit performs numerical control processing in accordance with a machining program instructed from paper tape or the like and drives a machine tool according to the results of said processing, causing a workpiece to be machined as instructed.
FIG. 1 is a block diagram of a numerical control unit known in the art. A machining program read from a tape reader 11 is stored into a memory 12. When it is executed, the machining program is read from the memory 12 on a block basis. The program is first processed by a controller 17 containing a central processing unit (CPU), a control program memory, etc. The controller 17 then performs numerical control processing in accordance with the machining program, driving the servo motor of a machine tool 1 to move a table or a tool post according to a move command or carrying out control, such as machine tool 1 coolant ON/OFF, spindle forward rotation/reverse rotation/stop, via a control box 13. The numeral 16 indicates a control panel having controls for giving zeroing, jog and other commands, 14 a manual data input device (referred to as the "MDI") employed to manually enter various data to the controller 17, and 15 a display unit for displaying the current position and other data of the machine, said devices 11 to 17 comprising a computer numerical control unit (referred to as the "CNC unit"). Including the CPU, control program memory, etc., as described above, the controller 17 in the CNC unit performs predetermined numerical control processing on the basis of the control program and machining program, thereby controlling the machine tool 1. Generally, the machining of a workpiece on a machine tool is a removing operation which takes away an unnecessary portion as chips by the relative motion between a tool and the workpiece. In this removing operation, machining efficiency is determined by the amount of chips taken away per unit time. To increase the machining efficiency, this chip removal amount per unit time may only maximized. Practically, however, there are certain restrictions, e.g., the limitation of the load applied to the machine and tool and the accuracy required for a surface to be machined. Moreover, the chip removal amount per unit time is determined by machining conditions. In a turning operation, the machining conditions are workpiece speed per unit time, the relative feedrate of the tool to the workpiece, and the depth of cut by the tool into the workpiece. In a milling operation, the machining conditions are tool speed per unit time, the relative feedrate of the tool to the workpiece, and the depth of cut by the tool into the workpiece. Namely, in either of the turning and milling operations, controlling the relative feedrate of the tool to the workpiece preferably is an extremely significant machining element in the removing operation. An unnecessary reduction in this relative feedrate deteriorates the machining efficiency and increases machining time. Its increase over a permissible value adversely affects machining accuracy and overloads the tool, machine, and other system components.
FIG. 2 is a block diagram of the key components of a known feedrate control section. The machining program is read from the memory 12 in FIG. 1 block by block. Each block is analyzed by the controller 17 and the result of the controller analysis is then fed to a pulse distribution processor 21 as CNC command data 20 in FIG. 2, i.e., as the move command and feedrate command of each axis. The pulse distribution processor 21 calculates for each axis a travel pulse per unit time from the move command and feedrate command of each axis and feeds them to the servo controller 22 of each axis. This travel pulse is used by the servo controller 22 to drive a servo motor 23 of the machine tool 1.
In the CNC unit, there are generally two ways of moving the tool; one is to move the tool on a straight line as shown in FIG. 3(a) illustrating linear interpolation, and the other is to move the tool on an arc as shown in FIG. 3(b) illustrating circular interpolation. In the case of the linear interpolation, a feedrate F is a vectorial value connecting a starting point and an end point as shown in FIG. 3(a) and axial velocity components are:
Fz=Fcosθ
Fx=Fsinθ
where Fx is a velocity component in an X axis direction, Fz a velocity component in a Z axis direction, and θ an angle between a Z axis and a vector indicated by the starting point A and end point B.
When the tool moves on an arc, the feedrate F is always a tangential velocity vector value at a point on the arc as shown in FIG. 3(b), i.e.: ##EQU1##
The moving axes of a CNC machine tool include straight-motion axes and rotating axes. The straight-motion axes move on a straight line relative to coordinate axes, e.g., X, Y and Z axes shown in FIG. 14 illustrating control axes in the numerical control unit. The rotating axes make a rotary motion relative to the X, Y and Z axes, e.g., A, B and C axes. In the conventional art, the CNC unit controls the straight-motion axes and rotating axes in an entirely identical manner, i.e., when controlling the rotating axes, the CNC unit provides move command values as angles and handles all numerical values given for the feedrate F as linear velocity. For example, the CNC unit treats 1° of the rotating axis as equivalent to 1 mm of the straight-motion axis, and processes the operations of the rotating and straight-motion axes equally, even though their operations are totally different inherently. In the CNC unit, the feedrate in a single specified block is always identical within that single block.
In the conventional CNC unit constructed as described above, the instructed feedrate F is the relative feedrate of the actual workpiece and tool if the straight-motion axes are specified. On the other hand, if the rotating axes, i.e., the axes rotating around the X, Y and Z axes, are specified, the specified feedrate works as the rotary speed of the rotating axis, i.e., angular velocity, as shown in FIG. 4(a) illustrating rotating axis feed control. Therefore, a relative feedrate FC of the workpiece and tool for the rotating axes is: ##EQU2## where F is the specified feedrate and r is a distance between the rotating axis center and tool. Hence, if it is desired to set the relative feedrate of the workpiece and tool to F, the feedrate F0 actually specified in the instruction must be as follows: ##EQU3## a first problem is that in programming, the specified feedrate F must be corrected according to Mathematical Expression 1 by taking into account the distance r between the rotating axis center and tool.
When the straight-motion axis and rotating axis are controlled simultaneously, the component of a numerical value provided by the feedrate F corresponding to each axis is identical to that employed when the straight-motion axes are controlled. It should be noted, however, that while the velocity components in straight-motion axis control remain unchanged in both magnitude and direction, those in rotating axis control change in direction as the tool moves (remain the same in magnitude), and the resultant composite feedrate in the tool advance direction varies as the tool moves. This is illustrated in FIG. 4(b) which shows feed control by the simultaneous control of the straight-motion and rotating axes. When the straight-motion axis (X axis) and rotating axis (C axis) are controlled simultaneously at the feedrate of F on the assumption that an X-axis increment command value (move command value in the X-axis direction) is x and a C-axis increment command value (rotation command value in the C-axis direction) is c, an X-axis feedrate (linear velocity) Fx and a C-axis feedrate (angular velocity) ω are: ##EQU4## Linear velocity Fc in C-axis control is represented by: ##EQU5##
Supposing that the velocity in the tool advance direction at starting point P1 is Ft and its X-axis and Y-axis velocity components are Ftx and Fty respectively, Ftx and Fty are represented: ##EQU6## where r is a distance between the rotating axis center and tool (unit: mm) and θ is an angle between point P1 and X axis at the center of rotation. According to Mathematical Expressions 1, 2, 3, 4 and 5, composite velocity Ft is: ##EQU7##
As indicated by Mathematical Expression 7, Ft is velocity at point P1. As the C axis rotates, the value of θ changes and the value of Ft also changes. To keep the relative speed, i.e., cutting speed Ft, of the workpiece and tool as constant as possible, therefore, the angular value instructed must be minimized and the variation of the θ value must be reduced. If the θ value of a portion to be machined is large, therefore, there arises a second problem that the feedrate must be decreased. Alternatively, the machining path may be sectioned and each section controlled by a separate block, requiring the processing of several blocks for an operation.
FIGS. 5(a)-(c) illustrate a program path in a corner, FIG. 5(a) indicating a programmed path and an actual tool path. Ideally, it is desired that the programmed path matches the actual tool path. Actually, however, they are always different in corner P due to a tracking delay, etc., in a servo system. Hence, if a tool 31 turns the corner P at an obtuse angle relative to a workpiece 30 as shown in FIG. 5(b), it turns in a direction of biting the workpiece. To avoid this, measures are taken, e.g., the feedrate of the tool 31 is reduced or the tool 31 is stopped at the corner for a while. Conversely, if the tool 31 turns the corner P at a sharp angle relative to the workpiece 30 as shown in FIG. 5(c), it does not bite the workpiece but problems arise, e.g., much of the metal is left uncut or a large load is suddenly applied to the tool 31.
FIGS. 6(a) and 6(b) illustrate a corner override function that may be used by some conventional CNC units to reduce the instructed feedrate within instructed distances Le and Ls before and after the corner P at an instructed ratio (override). However, the speed is only changed at two stages, i.e., a first change within the distances Le and Ls measured by starting at the corner P and a second change in the other areas. Accordingly, there is a third problem in that the feedrate must be set to meet the speed in the most reduced speed area within the distances Le and Ls starting at the corner P. Moreover, with this function, the feedrate tends to change too suddenly.
FIGS. 7(a) and 7(b) illustrate a drilling operation as an example of drilling a workpiece 30 with a drill tool 31. FIG. 7(a) shows that the tool 31 is just beginning to cut the workpiece 30. To carry out preferred machining, the feedrate should be decreased when the tool 31 makes contact with the workpiece 30 and increased when the tool 31 has completely bitten the workpiece 30. This is because, if the tool 31 is brought into contact with the workpiece 30 at an ordinary feedrate used for machining the workpiece 30, load is suddenly impressed to the tool 31, resulting in tool 31 breakage or position offset. Hence, the tool 31 is generally positioned up to point "a" slightly before the workpiece 30, the workpiece 30 is drilled at a reduced feedrate up to point "b" where the tool 31 would bite the workpiece 30 completely, and the workpiece 30 is drilled at the ordinary feedrate from point "b" onward.
An example in FIG. 7(b) shows that the tool 31 drills a through hole in the workpiece 30. In this case, if the tool 31 drills through the workpiece 30 at the ordinary feedrate, burrs are formed on the opposite surface of the workpiece. To avoid this, the workpiece 30 is generally drilled at the ordinary feedrate up to point "c" slightly before the tool 31 drills through the workpiece 30, and at a reduced feedrate from point "c" to a finish at point "d".
FIGS. 8(a) and 8(b) illustrate a drilling operation in a tapered portion of a workpiece, wherein FIG. 8(a) shows that the surface of the workpiece 30 that makes first contact with the tool 31 is beveled and FIG. 8(b) shows that the opposite surface is beveled. Particularly in these cases, unless the feedrate is dropped when the tool 31 makes contact with the workpiece 30 and when the tool 31 drills through the workpiece 30, drilling accuracy deteriorates, increasing the risk of breaking the tool. A fourth problem is that the machining path must be sectioned into several blocks to control the feedrate, as described above, and the feedrate for each block must be set for the worst-case scenario related to the cutting function performed in that block.
In FIGS. 9(a) and 9(b) illustrate the machining of a molding material workpiece, FIG. 9(a) shows that a workpiece 30, such as a molding material, is machined by a tool 31 and the workpiece has areas to be machined and unmachined by the tool. To increase machining efficiency and effectiveness, in accordance with the conventional teaching already described herein, the workpiece is machined in four blocks, a-b, b-c, c-d and d-e as shown in FIG. 9(b), even though the workpiece otherwise might be machined in a single block as shown in FIG. 9(a). In the machining of FIG. 9(b), it is desired at points where the workpiece is just beginning to be machined (points b and d) to decrease the feedrate of the tool 31 to soften impact on the tool 31 when it makes contact with the workpiece 30, and it is also desired at a point where the tool 31 leaves the workpiece 30 (point c) to reduce the feedrate so as not to generate burrs on the workpiece 30. However, since this change of feedrate further divides the blocks, there arises a fifth problem when the workpiece is actually machined as shown in FIG. 9(b). In particular, if quality errors still arise after consideration of the feedrate,at points b, c and d, it is inevitable that the entire feedrate must be reduced when the machining operation is performed.
FIG. 10 illustrating the machining operation of a midway die shows that the midway portion of a workpiece 30 is machined by a tool 31, wherein area a-b is a portion where the tool cuts into the workpiece and is gradually loaded, area b-c is a portion where certain load is kept applied to the tool, and area c-d is a portion where the load on the tool gradually decreases. The feedrate is generally determined with the feedrate in area b-c considered. However, if the tool is adversely affected by sudden overload in area a-b at the determined feedrate, there arises a sixth problem that it is inevitable to specify a reduced feedrate in consideration of feed in area a-b.
FIG. 11 illustrates a measurement function and shows that a workpiece 30 is measured with a measuring tool 31a, wherein the position of the workpiece 30 is measured by bringing the sensor tool 31a into contact with the workpiece 30. In this case, the measurement has been programmed in two blocks so that the tool is fed at a comparatively high rate up to point a slightly before the workpiece and at a lower measurement rate from point "a" to point "b". Because the machining path is divided into blocks in the vicinity of the measurement point (a-b) and the feedrate is reduced considerably in this area (a-b), there arises a seventh problem in that additional time is required to make measurements using the tool 31a.
FIG. 12 shows how control is carried out in no-entry area setting, illustrating a function which keeps checking whether a tool 31 enters an area 32 where the tool 31 must not enter and stops the tool at point "a" on a boundary if the tool is just beginning to enter the area 32. In this case, since the tool 31 is kept fed at the specified rate until it enters the no-entry area 32, there is an eighth problem in that the no-entry area must be defined slightly larger to ensure that the boundary is safely avoided.
In addition, generally the feedrate of a tool depends largely on an interrelation between the material of a workpiece and that of the tool. Hence, if the current tool is changed into a tool made of the other material during machining, there arises a ninth problem that the feedrate must be changed by making corrections to the machining program of the CNC unit.
Fuzzy inference logic may be applied to the control of machining operations. Fuzzy logic or fuzzy inference theory has been applied as an alternative to traditional expert systems that employ precise or "crisp" Boolean logic-based rules to the solution of problems involving judgment or control. Where the problems are complex and cannot be readily solved in accordance with the rigid principles of bilevel logic, the flexibility of fuzzy logic offers significant advantages in processing time and accuracy.
The theory of fuzzy logic has been published widely and is conveniently summarized in "Fuzzy Logic Simplifies Complex Control Problems" by Tom Williams, Computer Design magazine, pp 90-102 (March 1991).
In brief, however, the application of the theory requires the establishment of a set of rules conventionally referred to as "control rules", "inference rules" or "production rules" that represent the experience and know-how of an expert in the particular field in which a problem to be solved exists. The inference rules are represented in the form of IF . . . . (a conditional part or antecedent part) . . . THEN . . . . (a conclusion part or consequent part). This is conventionally referred to as an "If . . . Then" format. A large number of rules typically are assembled in an application rule base to adequately represent the variations that may be encountered by the application.
In addition, "membership functions" are defined for the "conditional parts" and the "conclusion parts". Specifically, variables in each of the parts are defined as fuzzy values or "labels" comprising relative word descriptions (typically adjectives), rather than precise numerical values. The set of values may comprise several different "levels" within a range that extends, for example, from "high" to "medium" to "low" in the case of a height variable. Each level will rely on a precise mapping of numerical input values to degrees of membership and will contain varying degrees of membership. For example, a collection of different levels of height from "high" to "low" may be assigned numerical values between 0 and 1. The collection of different levels is called a "fuzzy set" and the function of corresponding different height levels to numerical values is reflected by the "membership function. Conveniently, the set may be represented by a geometric form, such as a triangle, bell, trapezoid and the like.
Then, in the fuzzy inference control procedure, the inference control is carried out in several steps. First., a determination is made of the conformity with each of the input "labels" in the "conditional part" according to the inference rules. Second, a determination is made of conformity with the entire "conditional part" according to the inference rules. Third, the membership functions of the control variables in the "conclusion part" are corrected on the basis of the conformity with the entire "condition part" according to the inference rules. Finally, a control variable is determined on an overall basis, i.e., made crisp, from the membership functions of the control variables obtained according to the inference rules. The method of determining the control variable, i.e., obtaining a crisp value, is based on any of several processes, including the center of gravity process, the area process and the maximum height process.
The fuzzy inference rules and membership functions represent the knowledge of experts who are familiar with the characteristics of a complicated controlled object including non-linear elements, e.g. the temperature control of a plastic molding machine and the compounding control of chemicals, which are difficult to describe using mathematical models in a control theory. The fuzzy logic system employs a computer to perform the inference rule and membership function processing and thereby achieve expert-level inference.
In "Japanese Patent Disclosure Publication No. 95542 of 1990 (Cutting Adaptive Control System) fuzzy inference is applied to cutting and is made on the basis of an input signal from an external sensor. When fuzzy control is to be carried out in connection with the operations that encounter the above-stated third, fourth, fifth, sixth, seventh, eighth and ninth problems, the fuzzy inference that is to be performed must follow up the cutting of the machine tool. Since this requires very fast fuzzy inference to be made, software-executed fuzzy inference is not fast enough. Hence, a tenth problem results based on the requirement that a dedicated fuzzy chip, etc., must be installed in the CNC for performing processing on a hardware basis, leading to cost increases. Further, in a fuzzy inference method that is commonly applied to ordinary control operations (e.g., MIN ---- MAX or center of gravity method), if the results of Rules 1, 2 and 3 are composed as shown in FIG. 33(a)-33(c), the results of Rules 1 and 3 influence the result of composition but the result of Rule 2 has no influence on the result of composition. This indicates that the result of rule 2 is totally ignored, which poses an eleventh problem that the results of all rules have not been taken into consideration in deducing a conclusion.
Further, there are generally very important rules and not so important ones, i.e., rules are different in significance. However, there is a twelfth problem in that, conventionally, all set rules are treated equally in the known fuzzy inference methods.
SUMMARY OF THE INVENTION
An object of a first embodiment according to the present invention is to overcome the first problem by providing a CNC unit which allows a feedrate to be specified for a rotating axis as for a straight-motion axis and the specified feedrate F to be controlled to be kept at the relative speed of a tool and a workpiece. According to the first embodiment of the present invention, the setting of only a tool feedrate automatically provides that tool movement with respect to a rotating axis will be at a desired relative speed between a workpiece and a tool. This feature eliminates the necessity of specifically programming the tool feedrate in consideration of the distance from the rotating axis center to the tool, thereby significantly reducing the labor of a machining programmer.
An object of a second embodiment of the present invention is to overcome the second problem by providing a CNC unit which controls a specified feedrate F so as to be kept at the relative speed of a tool and a workpiece when movement with respect to both a straight-motion axis and a rotating axis are controlled simultaneously. According to the second embodiment of the present invention, merely the setting of only a tool feedrate guarantees the two-axis simultaneous control of a rotating axis and a straight-motion axis such that the desired relative speed between a workpiece and a tool is achieved. This allows machining to be carried out by only setting the tool feedrate in consideration of a cutting condition and eliminates the trouble of setting the feedrate under the worst-case scenario or sectioning a machining path into a plurality of blocks which is otherwise desired to be programmed as a single block, thereby considerably reducing the effort required from the machining programmer. Further according to the second embodiment of the present invention, a tool feedrate can be changed at the starting-point and end-point areas in a single block, whereby a machined section which conventionally must be segmented can be described in one block and the feedrate increased or decreased optionally and smoothly.
An object of the present invention is to overcome the third, fourth, fifth, sixth and seventh problems by providing a CNC unit which is capable of changing a feedrate within a single block.
An object of third, fourth and fifth embodiments according to the present invention is to overcome the third, fourth, fifth, sixth, seventh and eighth problems by providing a CNC unit which allows a feedrate to be controlled on the basis of preset rules within a single block without dividing a machining path into a plurality of blocks for controlling the feedrate and further allows the preset rules to be changed optionally, whereby an operator can incorporate machining know-how into a machining program.
Further, according to the third embodiment of the present invention, rules incorporating machining know-how are set in a knowledge storage section, an inferring section is provided independently of the knowledge storage section to ensure ease of additions and corrections to the rules, and the inferring section synthesizes the results of inference provided by a plurality of rules and deduces a final conclusion, whereby complex control can be easily achieved with various factors taken into consideration. In this manner, the conventional approach to changing the cutting condition step by step is improved by allowing the cutting condition to be changed in a function form, ensuring smooth cutting condition changes.
According to the fourth embodiment of the present invention, rules set in the knowledge storage section can be described in a production rule format, allowing an operator to understand the rules easily and further facilitate additions and corrections to the rules. Moreover, descriptions in the knowledge storage section are represented in rule and membership function formats to form the knowledge storage section of a two-step structure that macro, general-purpose knowledge is described by a rule and micro, special-purpose knowledge is represented by a membership function, achieving an approach which allows the optimum rule to be made up by adjusting the membership function after actual machining.
Employing tool position data in the CNC, the present invention has an advantage that fuzzy inference can be applied without making any modification, addition, etc., to hardware. The present invention can also execute fuzzy inference without carrying out actual cutting, allowing rules and membership functions to be tuned to a proper level for cutting simulation.
According to the fifth embodiment of the present invention, functions stored in the knowledge storage section can be changed optionally by the numerical control unit, allowing further optimum control to be carried out by setting the optimum function according to the machining status. This enables machining to be performed without requiring the operator to change functions if a function value may only be changed according to a particular rule after fundamental knowledge has been preset in the knowledge storage section.
An object of a sixth embodiment according to the present invention is to overcome the ninth problem by providing a CNC unit which allows a feedrate to be controlled on the basis of preset rules according to the material of a workpiece and that of a tool and further allows the preset rules to be changed optionally, whereby an operator can incorporate machining know-how into a machining program. A further object of the sixth embodiment is to provide a fuzzy inference section which allows inferring time to be reduced by making inference only on rules requiring judgement if there are many rules set.
According to the sixth embodiment of the present invention, inference is only made as to rules judged as necessary to be executed without needing to execute all rules stored in the knowledge storage section, allowing the inference speed to be increased when there are many rules.
Further, by making fuzzy inference of a feedrate from the materials of a workpiece and a tool, the present invention has an advantage that a feedrate can be extracted easily for a tool and workpiece made of new materials, i.e., a preferred conclusion can be deduced by fuzzy inference for new materials whose data has not yet been registered and considers the median hardness of the materials already registered.
An object of a seventh embodiment according to the present invention is to overcome the tenth problem by providing a fuzzy inference section which causes fuzzy inference to be made rapidly by software processing. According to the seventh embodiment of the present invention, fuzzy rules and their membership functions can be defined simultaneously and easily, requiring a small storage area for membership functions. Also, membership functions in the conclusion part of a fuzzy rule can be represented in a simple shape pattern, enabling the result of each rule to be inferred at high speed.
An object of an eighth embodiment of the present invention is to overcome the eleventh problem by providing a fuzzy inference section which causes the results of all given rules to be reflected on a conclusion. According to the eighth embodiment of the present invention, the results of fuzzy rules can be composed rapidly and all results of the rules reflected on a final conclusion, ensuring ease of membership function tuning. When combined with the seventh embodiment of the present invention, the eighth embodiment allows processing performed by dedicated hardware, etc., for the reduction of fuzzy inference time to be performed by software processing only.
An object of a ninth embodiment of the present invention is to overcome said twelfth problem by providing a fuzzy inference section which causes the significance of rules to be reflected on a conclusion.
According to the ninth embodiment of the present invention, a final conclusion can be deduced with the significance of each rule considered, and preferred inference can also be made by tuning such significance. In combination with the tuning of membership functions, the ninth embodiment allows more ideal rules to be set.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a known numerical control unit.
FIG. 2 is a block diagram showing the main parts of a prior art feedrate controller.
FIG. 3(a) illustrates linear interpolation known in the art.
FIG. 3(b) illustrates circular interpolation known in the art.
FIG. 4(a) illustrates rotating axis feed control known in the art.
FIG. 4(b) illustrates feed control by simultaneous control of a straight-motion axis and a rotating axis known in the art.
FIGS. 5(a)-5(c) illustrate program paths for machining a variety of corner shapes known in the art.
FIGS. 6(a) and 6(b) illustrate a corner override function known in the art.
FIGS. 7(a) and 7(b) illustrate a drilling operation known in the art.
FIGS. 8(a) and 8(b) illustrate drilling in a tapered area known in the art.
FIGS. 9(a) and 9(b) illustrate the machining of a molding material workpiece known in the art.
FIG. 10 illustrates the machining of a midway die known in the art.
FIG. 11 illustrates a machining measurement function known in the art.
FIG. 12 illustrates control in no-entry area setting known in the art.
FIG. 13 is a block diagram showing the key components of a feedrate controller according to the present invention.
FIG. 14 illustrates control axes in the known numerical control unit.
FIG. 15 is a flowchart concerned with the feedrate control of a rotating axis according to the present invention.
FIG. 16 is a flowchart concerned with the simultaneous speed control of the straight-motion axis and rotating axis according to the present invention.
FIGS. 17(a) and 17(b) show examples of rules for feedrate control set in a knowledge storage section according to the present invention.
FIG. 18 is a flowchart concerned with the processing of an inferring section according to the present invention.
FIG. 19 shows an example of rules for feedrate control set in the knowledge storage section according to the present invention.
FIGS. 20(a)-20(c) show an example of membership functions for feedrate control set in the knowledge storage section according to the present invention.
FIG. 21 shows an example of rules for feedrate control set in the knowledge storage section according to the present invention.
FIGS. 22(a) and 22(b) show an example of membership functions for feedrate control set in the knowledge storage section according to the present invention.
FIG. 23 shows an example of rules for feedrate control set in the knowledge storage section according to the present invention.
FIGS. 24(a) and 24(b) show an example of membership functions for feedrate control set in the knowledge storage section according to the present invention.
FIG. 25 illustrates how a distance between the no-entry area and tool is extracted according to the present invention.
FIG. 26 is a flowchart showing a sequence of extracting the distance between the no-entry area and tool according to the present invention.
FIG. 27 shows an example of a function stored in the knowledge storage section according to the present invention.
FIG. 28 is a flowchart showing a sequence of generating the function in the knowledge storage section according to the present invention.
FIGS. 29(a)-29(c) illustrate how functions are generated in the knowledge storage section at the time of measurement according to the present invention.
FIGS. 30(a)-30(c) show examples of data set in the knowledge storage section employed to correct the feedrate in accordance with the tool and workpiece materials according to the present invention.
FIG. 31 shows an example of a rule matrix in the knowledge storage section used to correct the feedrate in accordance with the tool and workpiece materials according to the present invention.
FIG. 32a shows an example of executing only corresponding rules in the rule matrix in the knowledge storage section used to correct the feedrate in accordance with the tool and workpiece materials according to the present invention; FIG. 32(b) illustrates a relevant flowchart.
FIGS. 33(a)-33(d) illustrate the composition of rules in the MAXMIN method for fuzzy control according to the conventional control art.
FIGS. 34(a)-34(c) illustrate a tool feedrate in a single block according to the conventional art.
FIGS. 35(a)-35(c) illustrate a tool feedrate in a single block according to the present invention.
FIG. 36 is a flowchart concerned with tool feedrate control in a single block according to the present invention.
FIG. 37 illustrates an inference method according to a MAX ---- MIN center of gravity method for fuzzy inference according to the conventional art.
FIGS. 38(a)-38(f) illustrate membership functions for fuzzy inference according to the conventional art.
FIGS. 39(a)-39(c) illustrate membership functions for fuzzy inference according to the present invention.
FIG. 40 illustrates the setting of production rules for fuzzy inference according to the present invention.
FIG. 41 illustrates an inference method for fuzzy inference according to the present invention.
FIG. 42 illustrates the setting of production rules for fuzzy inference according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A first embodiment according to the present invention will now be described in reference to the appended drawings. Referring now to FIG. 13, the numerals 20 to 23 indicate parts identical or corresponding to those in the conventional unit and 24 indicates a feedrate processor.
The operation of the present invention will now be described. As shown in a flowchart in FIG. 15 illustrating feedrate control, it is first determined whether a machining mode is a linear interpolation mode (G1 mode) or not by the feedrate processor 24 (step 100). If in the linear interpolation mode, then it is determined whether a move command is for a rotating axis alone or not (step 101). If it is for the rotating axis alone, a calculation is made to obtain a distance r between the starting point of a tool indicated by point A in FIG. 4(a) from where cutting starts and the center of the rotating axis (step 102). A compensation feedrate Fo is then calculated from a specified feedrate F according to Mathematical Expression 1 (step 103). The pulse distribution processor 21 in FIG. 13 processes this feedrate Fo in an identical manner to the conventional art as an instructed feedrate. By thus correcting the specified feedrate according to the distance r between the center of the rotating axis and the tool employed for machining, the relative speed of the workpiece and tool can be kept at the specified feedrate F.
A second embodiment according to the present invention will now be described in accordance with the appended drawings. In a similar manner to the first embodiment, as shown in a flowchart in FIG. 16 illustrating speed control for simultaneous control of a straight-motion axis and a rotating axis, it is determined whether the machining mode is the linear interpolation mode (G1 mode) or not by the feedrate processor 24 (step 110). If in the linear interpolation mode, then it is determined whether or not the move command is for two-axis simultaneous interpolation for rotating and straight-motion axes (step 111). If it is for the two-axis simultaneous interpolation, a speed change mode is switched on (step 112). When this speed change mode is on, the pulse distribution processor 24 in FIG. 13 performs pulse distribution while simultaneously correcting a feedrate so that Ft in Mathematical Expression 7 is always an instructed feedrate F, i.e., assuming that the corrected feedrate is Fo according to Mathematical Expression 7: ##EQU8##
Hence, ##EQU9## where x is an X-axis travel value and c is a C-axis travel value, which are always constant within a single block. Parameter "r" is a distance between the rotating axis center and tool position P1 in FIG. 4(b), and θ is an angle between the tool position P1 and X axis at the center of rotation. Since r and θ change momentarily as the tool moves, the then r and θ are found and the corrected feedrate Fo of the specified feedrate F is calculated according to Mathematical Expression 8 and employed as the specified feedrate to perform the pulse distribution. The specified feedrate is thus corrected momentarily in accordance with the r and θ of the tool position, thereby allowing the relative speed of the workpiece and tool to be kept at the specified feedrate F.
The second embodiment of the present invention will now be described in reference to the accompanying drawings. FIG. 34 shows a machining program 41, its operation 42 and a feedrate 43 known in the art, wherein "G01" indicates linear interpolation and "X ---- Y ---- " the coordinate values of an end point. "F ---- " defines a tool feedrate. When a command is given by the machining program as indicated by 41, linear interpolation is executed at the feedrate F from a current tool position (point S) to a specified end point (point E) as indicated by 42. This feedrate is a constant value F as indicated by 43. FIG. 35 shows a machining program 44, its operation 42 and a feedrate 45 according to the present invention. In the machining program 44, the part:
"G01X.sub.---- Y.sub.---- F.sub.---- "
is identical to that of the conventional machining program and so is its operation 42. The part:
"L1=.sub.---- L2=.sub.---- L3.sub.---- L4.sub.---- R1.sub.---- R2.sub.---- "
is a command for changing the tool feedrate at the starting-point and end-point areas of a block. This means that, as indicated by 45, the specified feedrate is changed to ##EQU10## from a starting point S to a point P1 a distance L1 away therefrom and is then restored to the value as it had been, i.e., F, up to a point P2 a distance L2 away from P1. Concerning an end-point are the feedrate is changed from F to ##EQU11## between a point P3 a distance (L3+L4) away from an end point E and a point P4 a distance L4 away from the same, and thereafter remains unchanged up to the end point.
Any of L1, L2, L3 and L4, if unnecessary, need not be specified. When unspecified, it is regarded as zero. When R1 or R2 is not specified, it is regarded as 100, which indicates that no speed change is made. The processing sequence of the example shown in FIG. 33 will now be represented in the form of a flowchart in FIG. 36. First, a check is made to see if the tool is located between S and P1 (step 501). If it is located between S and P1, the tool feedrate is set to R1% of the specified value (step 502). If not between S and P1, a check is made to see if the tool is located between P1 and P2 (step 503). If between P1 and P2, the feedrate is set to F*α (step 504), where α is a numeral represented by an expression indicated by 510. If not between P1 and P2, a check is made to see if the tool is located between P2 and P3 (step 505). If between P2 and P3, the feedrate is set to F as specified (step 506). If not between P2 and P3, a check is made to see if the tool is located between P3 and P4 (step 507). If between P3 and P4, the feedrate is set to F*β (step 508), where β is a numeral represented by an expression indicated by 511. If not between P3 and P4, then the tool exists between P4 and E and therefore the tool feedrate is set to R2% of the specified value (step 509).
It will be appreciated that a linear feedrate change made between P1 and P2 or between P3 and P4 in this embodiment may also be replaced by acceleration/deceleration pattern employing a method described in Japanese Patent Disclosure Publication No. 168513 of 1984, Japanese Patent Disclosure Publication No. 18009 of 1986 etc. In this case, it is only necessary to change the expressions 510 and 511 in the flowchart in FIG. 36.
A third embodiment of the present invention will now be described in relation to the appended drawings. Referring to FIG. 13, the numerals 20 to 23 indicate parts identical or corresponding to those in the conventional unit and 24 indicates a feedrate controller including a knowledge storage section 25 and an inferring section 26.
The operation of this embodiment will now be described. The knowledge storage section 25 contains a plurality of rules described for changing the feedrate at a corner as shown in FIGS. 17(a) and 17(b). For example, Rule 1 decreases the feedrate of a tool as the tool approaches the corner. Conventionally, as shown in FIGS. 6(a) and 6(b), the feedrate is simply switched according to the threshold values of a distance from the corner, i.e., when the tool has moved a certain distance Le close to the corner P, the feedrate is decreased to a particular value, and when the tool has moved a certain distance Ls away from the corner P, the feedrate is returned to the original value. In the embodiment of the present embodiment, as shown in FIG. 17(a), Function 1 defining a deceleration ratio according to the distance the tool has approached the corner allows the feedrate to be optionally changed. Rule 2 corrects the deceleration ratio of the tool feedrate according to the bevel angle of the corner. In general, as the bevel of the corner is sharper (closer to zero degrees), larger deceleration is made, and as the bevel is gentler (closer to 180 degrees), deceleration is smaller. In the example of the rule on the corner feed control set in FIG. 17(b), the feedrate is corrected by Function 2 of Rule 2 according to the bevel of the corner, with an average deceleration ratio preset in Function 1 of Rule 1.
FIG. 18 is a flowchart illustrating a procedure of how the inferring section 26 practically controls the feedrate in the corner by using the rules described in the knowledge storage section 25.
The inferring section 26 first reads Rule 1 from the knowledge storage section 25 (steps 200, 201), finds a distance between the tool and corner necessary for Rule 1 and gives it as input data (step 202). The inferring section 26 extracts the deceleration ratio Z1 of the feedrate according to that distance (step 203). In this case, the deceleration ratio of the tool feedrate corresponding to the distance from the corner is extracted by employing Function 1. In a similar manner, the inferring section 26 extracts from Rule 2 the deceleration ratio Z2 of the feedrate according to the bevel angle, of the corner (steps 204, 205, 201 to 203). Since N=2 results in YES at step 205 in the present embodiment, the inferring section 26 then composes the two deceleration ratios Z1 and Z2 provided by the two rules (step 206), thereby determining the tool feedrate Fo (step 207). In this case, the above composition is found by the product of each value.
"Mathematical Expression 9" Z=Z1*Z2* . . . . . *Zn
where n is the number of rules. The feedrate is determined by calculating the feedrate Fo corrected by multiplying the specified feedrate F by the feedrate deceleration ratio found according to Mathematical Expression 9. ##EQU12## where Z is a resultant deceleration ratio in %. Complex control based on a plurality of rules can be achieved by thus finding a machining condition (tool feedrate) by the composition of plural results. In addition, the knowledge storage section 25 and inferring section 26 individually provided allow more complicated rules to be defined.
In this embodiment, the rules described in an optional format in the knowledge storage section 25 as shown in FIGS. 17(a) and 17(b) may be described in the form of an operation expression of functions. In FIGS. 17(a) and 17(b), for example, Function 1 and Function 2 are defined and an expression for operating on the result of these functions are defined as follows: "Mathematical Expression 10"
F=F1*F2
Mathematical Expression 10 indicates that the product of the result found by the operation of Function 1 (F1) and Function 2 (F2) is employed as a final result.
The inferring section 26 finds the operation result of each function as shown in FIG. 18 and composes these results according to the defined expression. Mathematical Expression 9 at step 206 is the defined expression.
If, for example, the following operation expression has been defined,
"Mathematical Expression 11" F=(F1+F2+F3)/3*F4
it means that the results calculated by Functions 1, 2 and 3 are averaged out and the average value obtained is multiplied by the result calculated by Function 4, thereby providing the final result. A rule can thus be defined by optionally defined functions and an expression defining such operation methods.
A fourth embodiment according to the present invention will now be described in reference to the appended drawings. In FIG. 13, rules to be stored in the knowledge storage section 25 are to be described in the IF . . . THEN format of fuzzy inference control with the antecedent part (IF) indicating a condition under which a rule for changing the feedrate is judged and the consequent part (THEN) indicating operation to be performed if the condition in the antecedent part is satisfied or not satisfied. The rules are described in a so-called "production rule" format when values described in the rules are represented in a membership function format. This allows the knowledge storage section 25 to include "macro", general-purpose knowledge described by a rule and "micro", special-purpose knowledge represented by a membership function. The inferring section 26 deduces a conclusion by making fuzzy inference on the given membership functions on the basis of the rules described in the knowledge storage section 25.
As previously noted, fuzzy inference made in fuzzy control often employs the center of gravity in the result of the inference according to fuzzy-related maximum-minimum composition rules and is referred to as a maximum-minimum composition center of gravity method.
In this method, inference is performed in the following three steps as shown in FIG. 37:
(1) The conformity ai of each rule is calculated using given premises x 0 , y 0 ;
(2) An inference result Ci* is found for each rule; and
(3) The inference results obtained for all rules are synthesized to find C 0 . As its weighted center of gravity, the inference result Z 0 of all rules is calculated.
There are a variety of other techniques that have been devised, e.g., a method of contracting Ci 1/ai times instead of finding Ci* by taking away the top of Ci by ai as an interpretation of a fuzzy set C 0 , a C 0 non-fuzzing method which calculates a median instead of a center of gravity, and a height method which selects the element of a trapezoid set that gives a maximum value. From the past experience, it is known that among a number of such techniques, the maximum-minimum composition center of gravity method produces a very excellent result.
FIG. 19 and FIGS. 20(a)-(c) illustrate rules provided in the knowledge storage section 25 according to the present invention. The rules described therein are those employed for drill feedrate control shown in FIG. 7(a) and FIG. 8(a).
Referring now to FIG. 19, R1 to R5 indicate rules which are composed to deduce a conclusion in the present embodiment. POS is a distance between the tool 31 and workpiece 30 in FIG. 7(a), + indicating a distance before the tool 31 makes contact with the workpiece 30 and--that after contact. 0 indicates a contact point. A1 is a membership function shown in FIG. 20(a), instructing that the tool feedrate be reduced slightly before the tool makes contact with the workpiece, kept at the reduced value for a while after the tool has made contact with the workpiece until the tool completely bites the workpiece, and returned to the original value after the tool has bitten completely.
ANG in FIG. 19 indicates the bevel of a workpiece surface where the tool makes contact, which is classified into five types of B1 to B5 according to the degree of the bevel. FIG. 20(b) shows the membership functions of B1 to B5. FEED in FIG. 19 is the deceleration ratio of the tool feedrate, indicating the degree of reducing the tool feedrate, which is classified into five stages of C1 to C5. FIG. 20c shows the membership functions of C1 to C5.
The rules in FIG. 19 indicate that the feedrate of the tool is reduced according to the bevel of the workpiece surface which the tool makes contact with, from immediately before the tool makes contact with the workpiece to when the tool completely bites the workpiece.
An example of an inferring procedure is as follows. Taking Rule 1 as an example, the distance between the tool and workpiece is found and its conformity is evaluated by using the membership function of A1 in FIG. 20(a). The bevel of the workpiece surface with which the tool makes contact is also found and its conformity is evaluated by using the membership function of B1 in FIG. 20(b). Since the rule in the antecedent part is an AND condition, the smaller value of these conformities is adopted and a result is found by using the membership function of C1 in FIG. 20(c). In a similar manner, the results of Rules 2 to 5 are found and composed, thereby deducing a conclusion. A max-min AND is employed as an example of making an addition and a center of gravity method as the process of composition. The conclusion thus deduced is used to correct the tool feedrate F as indicated in the following expression, which is employed as the tool feedrate. ##EQU13## where Fo is the tool feedrate corrected, F is the feedrate instructed, and Z is the tool deceleration ratio deduced by fuzzy inference.
To the feedrate control in FIG. 7(b) and FIG. 8(b), the rules as shown in FIG. 19 and FIGS. 20(a)-(c) are also applicable in a similar manner. In this case, POS is a distance as to the surface of the workpiece 30 drilled through by the tool 31 and ANG is the bevel of this surface.
In FIG. 10, the tool feedrate is controlled so as to be corrected according to the moving direction of the tool. The tool moving direction of zero assumes that the tool cuts the workpiece in parallel therewith, i.e., between b-c, the direction of + that the tool cuts the workpiece in a workpiece biting direction, i.e., between a-b, and the direction of--that the tool cuts the workpiece in a workpiece leaving direction, i.e., between c-d. With these tool moving directions entered as input data, a conclusion is extracted using membership functions shown in FIGS. 22(a) and 22(b). According to the tool feedrate deceleration ratio thus obtained, the corrected feedrate is found using Mathematical Expression 12.
In this case, when the tool moving direction is --, i.e., when the tool moves away from the workpiece, the deceleration ratio is--and the corrected feedrate rises above the instructed feedrate.
In an example shown in FIG. 12, the distance between the tool 31 and no-entry area 32 is extracted for use as input data and the deceleration ratio is extracted according to membership functions shown in FIGS. 24(a) and 24(b) on the basis of rules shown in FIG. 23. The corrected tool feedrate is extracted by employing the extracted deceleration ratio according to Mathematical Expression 12. Here, it is determined where the tool exists relative to the no-entry area 32, among positions 1 to 8, as shown in FIG. 25 and the distance L between the tool 31 and no-entry area 32 is extracted as shown in a flowchart in FIG. 26 according to the tool position.
In the flowchart in FIG. 26, it is assumed that the tool position is (X, Y), the X-axis upper and lower limits of the no-entry area are XL and XS, and the Y-axis upper and lower limits of the no-entry area are YL and YS. At step 300, XL, XS, YL and YS are found to determine where the tool exists among the areas 1 to 8 shown in FIG. 25. At step 301, classification of one limit set is then made according to the values of XL, XS, YL and YS, and the distance L between the tool 31 and no-entry area 32 is extracted according to the classification result (step 302).
A fifth embodiment concerned with the present invention will now be described in reference to the appended drawings. When a molding material is machined as shown in FIG. 9(a), it is desired to control the feedrate according to a workpiece shape. A function itself is therefore generated automatically from the workpiece shape. In CNC units including an automatic program, some contain a pre-entered material shape which is used as the basis for generating the function. FIG. 27 shows the function automatically generated, wherein the normal feed rate is shown as a zero (0) deviation value and increases or decreases in commanded rate are shown as plus (+) or minus (-) values of ratio or percentage. According to the workpiece shape, the feedrate is reduced slightly before the tool makes contact with the workpiece (point a), returned to the original value slightly after the tool has passed point a, decreased again slightly before it comes out of the workpiece (point b), increased to a permissible limit in an area where the workpiece does not exist (between b-c), dropped slightly before the tool makes contact with the workpiece again (point c), and restored to the original value slightly after the tool has passed point c.
A process of generating the function in FIG. 27 will now be described in accordance with a flowchart in FIG. 28. A workpiece entry portion is judged (step 400) and the acceleration/deceleration pattern of the work entry portion is set (steps 401 to 403). The feedrate is first decreased down to Z1% between a position L1 away from the workpiece end face and a position L2 away therefrom (step 401). The feedrate is then kept at Z1% up to a position L3 inside the workpiece (step 402). The feedrate is returned to the original value up to a position L4 inside the workpiece (step 403). The above steps provide an acceleration/deceleration pattern wherein the feedrate is reduced immediately before the tool makes contact with the workpiece and returns to an ordinary value in a position where the tool has entered the workpiece by a certain distance. When the tool leaves the workpiece, a workpiece leaving portion is judged (step 404) and the acceleration/deceleration pattern of the portion where the tool leaves the workpiece is set (steps 405 to 407). The feedrate is first decreased down to Z2% between positions L5 and L6 before the tool leaves the workpiece (step 405). The feedrate is then kept at Z2% up to a position L7 away from the workpiece (step 406). The feedrate is raised to Z3% up to a position L8 away from the workpiece (step 407). The above steps provide an acceleration/deceleration pattern wherein the feedrate is reduced immediately before the tool leaves the workpiece and increases to a specified ratio after the tool has left the workpiece by a certain distance.
The function thus generated is used to correct the tool feedrate in actual machining. Namely, an acceleration/deceleration ratio is extracted relative to the specified feedrate F by using the function generated as shown in FIG. 27 and the corrected feedrate Fo is found as indicated by the following expression: ##EQU14## where Z is the acceleration/deceleration ratio provided by the function in FIG. 27.
In this embodiment, the acceleration/deceleration ratio employed in the vertical axis of the function may be an actual feedrate. In this case, Mathematical Expression 13 is replaced by:
"Mathematical Expression 14" Fo=Z
where Z is the corrected feedrate itself provided by the function.
When the measurement operation shown in FIG. 11 is performed, remeasurement may be made after the workpiece 30 has been measured by the tool 31a. Also in this case, as shown in FIGS. 29(a)-29(c), the automatic generation of a function indicating the acceleration/deceleration pattern of a second feedrate achieves more accurate and useful measurement. In FIG. 29(b), Function 1 is the tool feedrate deceleration pattern of the first measurement. Because of the first measurement, its deceleration band is wide and its deceleration ratio is small in order to economize on measurement time.
In general, measurement accuracy decreases in proportion to the feedrate in measurement. According to the first measurement, the actual position of the workpiece is estimated with the drift value, etc., of a measurement sensor taken into account. A deceleration pattern like Function 2 in FIG. 29(c) is automatically generated in consideration of a predetermined clearance value for the estimated position of the workpiece. In Function 2, the deceleration band is narrow in order to reduce measurement time and the deceleration ratio is large in order to enhance measurement accuracy.
A sixth embodiment according to the present invention will now be described in reference to the appended drawings. Generally the feedrate of the tool greatly relies on the material of the workpiece to be machined and that of the tool employed for machining. Hence, it may be conceived that a standard feedrate is set and corrected according to the combination of the workpiece and tool materials. FIGS. 30(a)-30(c) show rules for the concept, wherein Ti (i=0 to 9) indicates a tool material and Wz (z=0 to 9) a workpiece material. If both the TOOLs and WORKpieces are classified finely (10 stages) as shown in FIGS. 30(b) and 30(c), the number of rules increases significantly. In the case of FIG. 30(a), the number of rules extends to 100 as indicated in FIG. 31. Hence, an attempt to perform an operation on all rules and extract their results will take an excessive amount of time in inference. Therefore, the only rules executed are those which relate to the TOOLs and WORKpieces corresponding to the material hardness of given tools and workpieces.
For example, if the material hardness of the tools and workpieces is given exactly in numerical values, membership functions indicated in FIG. 30(a) corresponding to these values are only inferred. If the membership function of T5 has the hardness value of α to β and the hardness K of the given tool is as follows:
α≦K≦β
T5 is judged as corresponding. If the material hardness of the tools and workpieces is ambiguous and given in membership functions, the membership functions of any of T0 to T9 and W0 to W9 falling within the range of the hardness of said given membership functions are judged as corresponding. If the areas of "Tool" and "Work" identified by arrows in FIGS. 30(a) and 30(b), respectively, are facts given to this membership function, then the membership functions whose areas consist of these given facts are "T4" and "T5" for "Tool", and "W6" and "W7" for "Work".
FIG. 32(a) indicates that since the membership functions of T4 to T5 among the Tools and the membership functions W6 to W7 among the workpieces correspond to the material hardness as the result of extraction, only rules F64, F65, F74 and F75 are executed to deduce a conclusion.
FIG. 32(b) is a flowchart indicating an algorithm which extracts rules to be executed. In FIG. 32(b), "i" indicates the number of a rule, and "j" indicates the number of a condition part of each rule. The number of rules in n, and the number of condition parts of each rule is mi. First, the i and j parameters are initialized, specifically, initialize as i=1 (Step 601), and next initialize as j=1 (Step 602). Then, extract the area (α, β) of a membership function in an ith rule with a jth conditional part (Step 603). An area of membership function is a range of the value which a defined membership function takes in a horizontal direction. Check if Dij (fact), which is a value given to this membership function, exists in the area extracted in Step 603 (Step 604). In case Dij is not a specific value, for example, in case Dij is also a membership function, check if there is an overlapping section between Dij and (α, β).
If Step 604 judges YES, then the value of j is increased by 1 (Step 605). Check if the value of j is within mi, i.e., check if there is a membership function of a conditional part which has not been judged by ith rule (Step 606). If Step 606 judges YES, then return to step 603. If its judgment is NO, then move to Step 607. In case Step 604 judges YES, turn the execution flag of the ith rule OFF (Step 608). In case step 606 judges NO, turn the execution flag of ith rule ON (Step 607). Execution flags at each of the rules are there to identify whether or not each rule should be executed. When fuzzy inference is made, only those rules whose flags are ON should be executed.
In processings from Step 602 to 608 if there is a rule without Dij, a value given to membership function, in an area of membership function of a conditional part of each rule, the rule will become 0 without fail so long as an inference is made with a MAX -- MIN method. Because of it an execution flag of a rule is turned off since there is no need to make an inference.
Next increase the value of i by 1 (Step 609). Check if i is a value within n, i.e., check if it has been judged referring to all rules (Step 610). If Step 610 judges YES, i.e., there are still some rules to be judged then return to Step 602. If it is NO, the processing will be ended.
A seventh embodiment of the invention will now be described with reference to the appended drawings. Generally, various shapes (51 to 56) as shown in FIGS. 38(a)-38(f) may be conceived for membership functions employed for fuzzy inference.
In defining rules conventionally with reference to the example in FIG. 23, therefore, the rules are defined as indicated by R1 to R3 in FIG. 23 and membership functions A1, A2, A3, B1, B2 and B3 must separately be defined anew. For this reason, a man-machine interface dedicated to defining membership functions must be prepared and a large area set aside in a system for storing membership functions.
To solve such a problem, the present invention has enabled membership functions to be represented in a specific shape pattern and defined simultaneously with rules. An example is given by 57 in FIG. 39(a), wherein all membership functions are defined in the form of an isosceles triangle and Li indicates a center position and li a half length of the base of the isosceles triangle. When membership functions are defined as described above, they can be defined by the center (i.e., center of gravity position) Li and the half base length li of the shape 57 and it is therefore only necessary to enter Li and li. This allows rules and membership functions to be defined simultaneously as shown in FIG. 40, in relation to the rules in FIG. 23.
Referring now to FIG. 40, A1, A2, A3, B1, B2 and B3 indicate the centers of respective membership functions and a1, a2, a3, b1, b2 and b3 the half base lengths of respective membership functions.
Membership functions may also be represented in other shape patterns as indicated by 58 in FIG. 39(b) wherein a dead zone is provided, or as indicated by 59 in FIG. 39(c) wherein the shape is asymmetrical. In this case, membership functions may be represented as (Li, li, mi) by using an additional parameter.
In general, most membership functions are defined in the shape indicated by 57 in FIG. 39(a). Hence, when membership functions are represented in the shape pattern of an isosceles triangle as indicated by 57 in deducing a conclusion from the conclusion part of a rule, an inference result is found as follows in relation to the membership functions 61 in the conclusion part for conformity α (≦α≦1) as shown in FIG. 41. Since the shape is an isosceles triangle, the center of gravity position is Li and the area value Si is:
Si=(lj+li)*α/2
where lj is the half upper-base length of a trapezoid, li the half lower-base length thereof, and α a height.
li:lj=1:(1-α)
Therefore
lj=(1-α)li
Hence ##EQU15## Hence, the value of Si can be easily calculated by α and li and the conclusion can be deduced fast.
An eighth embodiment according to the present invention will now be described. In synthesizing the inference result of each rule as shown in FIG. 37 in the known fuzzy inference method, the shapes of the membership functions in the result of each rule are overlapped and the center of gravity of a shape thus obtained is found.
FIG. 33(d) shows a shape obtained by synthesizing the results of three rules illustrated in FIGS. 33(a)-33(c) and composing the shapes of three membership functions in the MAX MIN method. When the conclusion of each rule is thus composed, the shapes must be composed to extract a new shape, which takes time for processing, and in the example of FIGS. 33(a)-33(d), the result of Rule 2 has no influence of a final conclusion. Namely, referring to FIG. 33(b), the center position of the membership function in the conclusion part of Rule 2, if slightly shifted, does not have any influence on the final conclusion. Such a case has posed a problem that it is difficult to tune membership functions in the conventional method. In the present invention, therefore, a final conclusion L is found by making inference as indicated by Mathematical Expression 8 from the center of gravity position Li and area Si in the result of each rule. Here, n is the number of rules. In this method, the result of each rule always influences the final conclusion and shapes are not composed, whereby fuzzy inference processing can be performed at high speed. When combined with the seventh embodiment method, the eighth embodiment offers much faster processing.
A ninth embodiment according to the present invention will now be described. Since all rules are treated equally in the known fuzzy inference, the significance of specific rules cannot be reflected on a conclusion. Actually, however, the significance of rules must be taken into consideration in deducing a final conclusion. The present invention defines the significance of each rule as shown in FIG. 42 using, for example, VAL. VAL is given a larger value for a more significant rule and a less value for a less significant rule.
Assuming that the significance of each rule is βi, the final conclusion L is found by making inference as indicated by Mathematical Expression 9 from the center of gravity position Li and area Si. Here, n is the number of rules. In this way, fuzzy inference can be made with the significance of each rule taken into consideration. In addition, because the significance βi is designed to permit a negative value, a negative rule can also be set. Specifically, the setting of a negative value to the significance renders an area value in the conclusion part of a rule negative, thereby setting a negative rule. This allows the setting of the following rule that cannot be defined in the conventional method:
If A is A1 THEN B is not B1 | A numerical control unit for changing a cutting condition of a machine tool during machining of a workpiece. The numerical control unit includes a knowledge storage section for storing at least two rules for changing the cutting condition. At least one of the rules defines a rate at which movement of the machine tool is decelerated based on the position of the machine tool with respect to a corner of the workpiece. Other rules may define the rate at which movement of the machine tool is decelerated based on the shape of the corner of the workpiece being machined. Also, the other rules could be established based on the material of the tool or workpiece. The knowledge storage section further includes a rule description part and assessment functions. The numerical control unit further includes an inferring section for inferring the optimum value of the cutting condition on the basis of at least the rule or rules which define the rate at which movement of the machine tool is decelerated based on the position of the machine tool with respect to the corner of the workpiece. The numerical control unit then causes a workpiece to be machined in accordance with the cutting condition inferred by the inferring section. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Art
This invention relates to a DNA strand having an ability in biotechnological production of α-acetolactate decarboxylase (hereinafter called α-ALDCase) as produced by Acetobacter aceti subspecies xylinum IFO 3288, to a yeast belonging to Saccharomyces cerevisiae transformed with the DNA strand so that it has capability of producing α-ALDCase, and to production of alcoholic beverages by the yeast transformed.
2. Prior art
Alcoholic beverages such as beer, sake, wine, etc., are generally produced by adding a yeast belonging to Saccharomyces cerevisiae to a starting material liquid for fermentation such as wort, fruit juice, etc., and subjecting the mixture to alcohol fermentation. In the fermentation process, the yeast will produce α-acetolactate (hereinafter called α-AL) as the intermediate substance for biosynthesis of valine and leucine which are amino acids necessary for the growth of itself, and leak it inevitably out of the cell, namely into the fermented liquor. The α-AL which has thus become to exist in the fermented liquor will change spontaneously to diacetyl (hereinafter called DA) through the non-enzymatical reaction in the fermented liquor.
DA is a substance having strong objectionable odor called generally as "cooked odor" or "DA odor" and, in order to produce an alcoholic beverage excellent in flavor (namely without DA odor), the content of α-AL and DA in the fermented liquor is required to be decreased to a low level so that the total DA content will not finally exceed the discrimination threshold of DA odor in the alcoholic beverage (e.g. 0.05 to 0.1 mg/liter in the case of beer) even if α-AL may be all changed to DA.
While DA in the fermented liquor is converted to acetoin which is tasteless and odorless relatively rapidly in the co-presence of yeast, α-AL in the fermented liquor will not be changed by yeast, but it becomes decomposable with yeast only after it has been changed to DA by non-enzymatical chemical reaction. However, since the conversion of α-AL to DA in the fermented liquor proceeds at a very slow rate, this reaction becomes the rate-limiting step, whereby the fermented liquor is required to be aged under the co-presence of yeast for a long time in order to obtain an alcoholic beverage with low content of α-AL and DA (namely without DA odor).
α-ALDCase is an enzyme having the property of converting α-AL to acetoin and has been known to be produced by various Voges Proskauer reaction positive bacteria such as Enterobacter aerogenes, Bacillus licheniformis, Lactobacillus casei, Bacillus brevis, Enterobacter cloacae, and Acetobacter bacteria (such as A. rancens, A. aceti, etc), etc.
SUMMARY OF THE INVENTION
The present invention provides a DNA strand having an ability in biotechnological production of α-ALDCase, which is useful for production of alcoholic beverages having no DA odor within by far shorter period as compared with the prior art method, and a yeast endowed with α-ALDCase producing ability by transformation with the DNA strand.
More specifically, the DNA sequence coding for α-ALDCase according to the present invention is characterized in that it has a nucleotide sequence, or, in other words, a nucleotide sequence coding for a polypeptides having α-ALDCase activity, of which amino acid sequence, namely an amino acid sequence of the polypeptides, is substantially from A to B of the amino acid sequence shown in FIG. 1.
On the other hand, the yeast belonging to Saccharomyces cerevisiae according to the present invention is characterized in that it is yeast which has been transformed with a DNA sequence coding for the polypeptides having α-ALDCase activity, of which amino acid sequence is substantially from A to B of the amino acid sequence shown in FIG. 1.
The present invention also relates to the use of the DNA sequence or strand and the yeast.
Accordingly, the process for producing an alcoholic beverage according to the present invention is characterized in that fermenting a material for fermentation by a yeast which is a yeast which has been transformed with a DNA sequence coding for the polypeptides having α-ALDCase activity, of which amino acid sequence is substantially from A to B of the amino acid sequence shown in FIG. 1.
The DNA strand according to the present invention can impart α-ALDCase producing ability to various microorganisms, for example, Saccharomyces cerevisiae to reduce its o-AL producing ability, or it can be effectively utilized in biotechnological production of α-ALDCase.
Also, since the yeast according to the present invention is such that its ability to produce α-AL (correctly leaking of α-AL out of the cell) is reduced, if the starting material liquor for fermentation is fermented with this yeast, the level of α-AL in the fermented liquor will become very low to give a result that the aging period required for treatment of α-AL in the fermented liquor, and therefore the production period of alcoholic beverage can be remarkably shortened. In the yeast of the present invention, its α-AL producing ability is reduced probably because the α-AL, even if produced within the cell in the fermentation process, will be converted to acetoin by α-ALDCase also produced within the cell.
Undesirable odors are problems also in production of fermentation products other than alcoholic beverages, such as vinegar. The undesirable odor in production of vinegars may also be ascribable to their content of DA, for example.
Accordingly, the DNA sequence coding for α-ALDCase in accordance with the present invention may also be used in such a way that acetic acid bacteria are transformed with the DNA sequence and the transformant thus produced is used in production of vinegars which are improved in their reduced undesirable odors.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates the nucleotide sequence of the DNA strand according to the present invention and the amino acid sequence deduced from the nucleotide sequence;
FIG. 2 illustrates the structure of pAX43;
FIG. 3 is a flow chart for sub-cloning the α-ALDCase gene;
FIG. 4 is a flow chart for obtaining GPD promoter (SalI-BglII);
FIG. 5 is a flow chart for obtaining PGK terminator (SacI-SalI);
FIG. 6 is a flow chart for constructing pAX43;
FIG. 7 illustrates site-specific mutation;
FIG. 8 is a flow chart for obtaining GPD promoter (BamHI-HindIII);
FIG. 9 is a flow chart for obtaining PGK terminator (Hind III-SalI);
FIG. 10 is a flow chart for obtaining pAX50A to E;
FIG. 11 is a flow chart for constructing pAX43KL;
FIG. 12 illustrate the structure of pAX43KL.
FIG. 13 illustrates the structure of a DNA fragment containing GPD promoter+α-ALDCase gene+PGK terminator;
FIG. 14 illustrates the structure of pAS5;
FIG. 15 is a flow chart for constructing pAX60G2; and
FIG. 16 is a flow chart for constructing pAS5.
DETAILED DESCRIPTION OF THE INVENTION
α-ALDCase gene
Definition
The DNA sequence or strand, which will hereinbelow been sometimes called just as "DNA strand", according to the present invention having an ability in biotechnical production of α-ALDCase, namely the α-ALDCase gene, is one which has a nucleotide sequence which codes for a polypeptides having α-ALDCase activity, which amino acid sequence is substantially from A to B of the amino acid sequence shown in FIG. 1.
Here, the "DNA strand" means complementary double strands of polydeoxyribonucleic acid having a certain length. And, since the "DNA strand" is specified by the amino acid sequence of the polypeptides encoded thereby and the polypeptides has a finite length as mentioned above, the DNA strand also has a finite length. However, while the DNA strand contains a gene coding for α-ALDCase and is useful for biotechnological production of the polypeptides, such biotechnological production cannot be effected only by the DNA strand having the finite length, but biotechnological production of the polypeptides is rendered possible under the state where a DNA strand of a suitable length is linked upstream to its 5'-end and/or downstream to its 3'-end.
Accordingly, the "DNA strand" as mentioned in the present invention is inclusive, in addition to the DNA strand of a specific length (the length of A-B in terms of the corresponding amino acid sequence in FIG. 1), of those in the form of a linear DNA or a circular DNA strand containing the DNA strand of the specific length. This is why the DNA sequence in accordance with the present invention is defined as "having a nucleotide sequence coding for a polypeptides".
Of the existing forms of the DNA strand according to the present invention, typical are the plasmid form comprising the DNA strand as a part of the constituents and the form existing in a microorganism, particularly E. coli, yeast and acetic acid bacteria, as the plasmid form or the integrated form into the genome.
The preferable existing form of the DNA strand according to the present invention comprises the DNA strand of the present invention as a foreign gene linked to a promoter and a terminator so that the α-ALDCase gene can be expressed stably in a microorganism, which exists in the microorganism as a plasmid form or an integrated form into the genome. As the promoter and the terminator, known promoters and terminators can be used in a suitable combination.
Polypeptides encoded by the gene
As mentioned above, the DNA strand according to the present invention is specified by the amino acid sequence of the polypeptides encoded thereby. The polypeptides has α-ALDCase activity and has an amino acid sequence which is substantially from A to B of the amino acid sequence shown in FIG. 1. Here, "amino acid sequence which is substantially from A to B of the amino acid sequence shown in FIG. 1" indicates that some of the amino acids can be deleted or substituted or some amino acids can be added, etc., so long as the polypeptides has α-ALDCase activity.
A typical polypeptides having α-ALDCase activity in the present invention is of the amino acid sequence from A to B in FIG. 1, consisting of 235 amino acids, which amino acid sequence has not been known in the prior art.
As shown in the above, the statement "amino acid sequence which is substantially from A to B of the amino acid sequence shown in FIG. 1" indicates that some modification can be applied to the amino acid sequence. One example of a polypeptides which has such a modified amino acid sequence is one having an amino acid sequence of A 1 to B in FIG. 1, which amino acid sequence has 69 amino acids added upstream to the end A of the amino acid sequence from A to B in FIG. 1, namely has amino acids added corresponding to nucleotide sequence of from No. 212 to No. 418, since this polypeptides still has an α-ALDCase activity even though the activity is ca. 10% of that of the polypeptides having the amino acid sequence of from A to B in FIG. 1. Similarly, polypeptides having amino acid sequences of A 2 to B, A 3 to B, A 4 to B, A 5 to B and A 6 to B, respectively, wherein those having the amino acid sequences of A 3 to B, A 5 to B and A 6 to B, respectively, have N-terminus of Met instead of Val, fall within the scope of polypeptides in accordance with the present invention.
The present invention concerns basically with DNA strands, but the position of the present invention referred to hereinabove, namely the polypeptides which have amino acids added outside to the polypeptides of amino acid sequence A to B in FIG. 1 fall within the scope of polypeptides in accordance with the present invention tells, in turn, that the DNA strands which code for such "longer" polypeptides than that of amino acid sequence of A to B in FIG. 1 fall within the scope of the DNA strands in accordance with the present invention, since the nucleotide sequence encoding such longer polypeptides than that of amino acid sequence of A to B in FIG. 1 does have the nucleotide sequence encoding the polypeptide of amino acid sequence of A to B.
Nucleotide sequence of DNA strand
The DNA strand coding for α-ALDCase is one having the nucleotide sequence from A to B in FIG. 1 or one of those having nucleotide sequences corresponding to the changes in amino acid sequence of α-ALDCase as mentioned above or degenerative isomers thereof. Here, the "degenerative isomer" means a DNA strand which is different only in degenerative codon and can still code for the same polypeptides. For example, relative to the DNA strand having the nucleotide sequence of A to B in FIG. 1, the DNA strand having a codon corresponding to any one of the amino acids changed from, for example, the codon (GGC) corresponding to Gly at the carboxy terminal end to, for example, GGT which is in degenerative relationship therewith, is called a degenerative isomer in the present invention.
A preferable specific example of the DNA strand according to the present invention has at least one stop codon (e.g. TGA) in contact with the 3'-end.
Further, upstream to the 5'-end and/or downstream to the 3'-end of the DNA strand of the present invention, a DNA strand with a certain length can be continuous as the non-translation region (the initial portion downstream to the 3'-end is ordinarily a stop codon such as TGA).
The nucleotide sequence of the DNA strand shown in FIG. 1 was determined for the gene coding for the α-ALDCase cloned from Acetobacter aceti subspecies xylinum IFO 3288 according to the dideoxy method.
Acquirement of DNA strand
One means for obtaining the DNA strand having the nucleotide sequence coding for the amino acid sequence of the above α-ALDCase is to synthesize chemically at least a part of the DNA strand according to the method for synthesis of polynucleotide.
It would, however, be preferable to obtain the DNA strand from the genomic library of Acetobacter aceti subspecies xylinum IFO 3288 according to the method conventionally used in the field of genetic engineering, for example, the hybridization method with the use of a suitable probe.
In this invention, the present inventors cloned the DNA strand of the present invention from the above genomic library by use of the shot gun method, because the nucleotide sequence coding for the α-ALDCase of Acetobacter aceti subspecies xylinum IFO 3288 and the amino acid sequence of α-ALDCase were not known (see Examples shown below about its details).
Yeast having ability to produce α-ALDCase
The DNA strand of the present invention cloned as described above contains the genetic information for making α-ALDCase, and therefore this can be introduced into the yeast used generally as the yeast for fermentation of alcoholic beverages (Saccharomyces cerevisiae) to transform the yeast, whereby a yeast for fermentation having α-ALDCase producing ability, namely with reduced α-AL producing ability, can be obtained.
Yeast
The yeast to be transformed in the present invention may be a yeast belonging to Saccharomyces cerevisiae as described in "The Yeasts, a Taxonomic Study" third edition (Yarrow, D., ed. by N. J. W. Kreger-Van Rij. Elsevier Science Publishers B. V., Amsterdam (1984), p.379) and its synonym or a mutant, but for the purpose of the present invention, a yeast for fermentation of alcoholic beverages belonging to Saccharomyces cerevisiae, specifically beer yeast, wine yeast, sake yeast, etc., are preferred. Specific examples may include wine yeast: ATCC 38637, ATCC 38638, IFO 2260 (wine yeast OC2); beer yeast: ATCC 26292, ATCC 2704, ATCC 32634; sake yeast: ATCC 4134, ATCC 26421, IFO 2347 (Sake yeast Kyokai #7), etc.
To further comment on the properties of these yeasts for fermentation, as the result of selection and pure cultivation over long years for the properties suitable for fermentation, namely efficient fermentation of the starting material liquid for fermentation, production of alcoholic beverages with good flavor and stable genetic properties, etc., as the index, they have become polyploids which will undergo genetically cross-segregation with extreme difficulty and have lost spore forming ability substantially completely. For example, in the case of beer yeast practically used, while it is enhanced in the ability to assimilate maltose, maltotriose which are sugar components in the wort, it has lost its wild nature, for example, it is crystal violet sensitive, etc.
Transformation
It has been confirmed for the first time by the present inventors that transformation of a yeast with the DNA strand of the present invention resulted in reduction of its α-AL producing ability. However, the procedure or the method itself for preparation of the transformant can be one conventionally employed in the field of molecular biology, bioengineering or genetic engineering, and therefore the present invention may be practiced according to these conventional techniques except for those as described below.
For expression of the gene of the DNA strand of the present invention in a yeast, it is first required that the gene be carried on the plasmid vector which is stable in the yeast. As the plasmid vector to be used in this operation, all of the various kinds known in the art such as YRp, YEp, YCp, YIp, etc., can be used. These plasmid vectors are not only known in literatures, but also they can be constructed with ease.
On the other hand, for the gene of the DNA strand of the present invention to be expressed in a yeast, the genetic information possessed by the gene is required to be transcribed and translated. For that purpose, as the unit for controlling transcription and translation, a promoter and a terminator may be linked upstream to the 5'-end and downstream to the 3'-end of the DNA strand of the present invention, respectively. As such promoter and terminator, various kinds such as ADH, GAPDH or GPD, PHO, GAL, PGK, ENO, TRP, HIP, etc., have been already known in the art and any of these can be utilized also in the present invention. These are not only known in literatures, but also they can be prepared with ease.
As the marker for selecting the transformant to be obtained by the present invention, a resistant gene to G418, hygromycin B, a combination of methotrexate and sulfanylamide, tunicamycin, ethionine, compactin, copper ion, etc., can be employed.
For having the DNA strand of the present invention held more stably in a yeast, the DNA strand can be integrated into the genome of the yeast. In this case, for making easier integration of the DNA strand of the present invention carried on the plasmid vector into the genome, it is desirable to insert a DNA having high homology with the genome DNA into the plasmid vector, and examples of DNA for this purpose may include rRNA gene, HO gene, etc.
Among them, it has been known that rRNA gene is repeated tandemly for about 140 times in haploid yeast genome (Journal of Molecular Biology 40, 261-277 (1969)). Due to this specific feature, when this sequence is utilized as the target sequence for recombination, there are the following advantages obtainable as compared with the case when utilizing other gene sequence.
1. It is expected that the transformation frequency may be elevated.
2. The change in the corresponding trait of the target sequence by recombination may be considered to be negligible.
3. It becomes possible to integrate a plural number of foreign genes into the genome by repeating a series of operations of integration of plasmid and excision of the vector sequence.
Also, the DNA strand which can be used for transformation of a yeast in the present invention can also code for a polypeptides different from the polypeptides of A to B shown in FIG. 1, so long as it has α-ALDCase activity, as mentioned previously.
Transformation of a yeast with the plasmid thus prepared can be done according to any method suited for the purpose conventionally used in the field of genetic engineering or bioengineering, for example, the spheroplast method [Proceedings of National Academy of Sciences of the U.S.A. (Proc. Natl. Sci. USA), 75, 1929 (1978)], the lithium acetate method [Journal of Bacteriology (J. Bacteriol.), 153, 163 (1983)], etc.
The yeast of the present invention thus obtained is the same as the yeast before transformation in its geno type or phenotype except for the new trait according to the genetic information introduced by the DNA strand of the present invention (that is, endowed with α-ALDCase producing ability to consequently decompose α-AL within the cell, thereby lowering the amount of α-AL leaked out of the cell), the trait derived from the vector used and the defective corresponding trait due to the defect of a part of the genetic information during recombination of the gene which might have occurred. Further, the beer yeast obtained by integrating the DNA strand of the present invention into the yeast genome by use of YIp type plasmid, followed by excision of unnecessary vector sequence has no trait inherent in the vector employed. Accordingly, the yeast according to the present invention can be used under essentially the same fermentation conditions for the yeast for fermentation of the prior art. It is possible, on the other hand, to reduce α-AL production in the fermented liquor, and therefore the α-AL content in the fermented liquor is consequently low, whereby the aging period of the fermented liquor required for its treatment can be remarkably shortened.
Production of alcoholic beverages
The use of the yeast in accordance with the present invention in fermentation of materials for fermentation will result in production of alcoholic beverages with the advantages referred to above.
The types of materials for fermentation depend, of course, on the type of alcoholic beverages to be produced, and wort is used for beer production, and fruit juice, particularly grape juice, for wine.
Yeast can be in a slurry, in an immobilized state or in any suitable state or form. Fermentation conditions can also be those conventionally used with conventional yeasts.
The alcoholic beverages produced have a lower content of α-AL thanks to the use of the yeast of the present invention which is endowed with capability of α-ALDCase production, and the time required for producing alcoholic beverages having lower DA odor by aging is significantly reduced, as referred to hereinabove.
EXPERIMENTAL EXAMPLES
(1) Cloning of α-ALDCase gene
(i) Purification of chromosomal DNA of α-ALDCase producing strain
By culturing over night under aeration Acetobacter aceti subspecies xylinum IFO 3288 (procured from Institute for Fermentation, Osaka, Japan) in 100 ml of YPD medium containing 1% yeast extract, 2% peptone and 2% glucose, 0.7 g of wet microorganism cells was obtained.
This was resuspended in 30 ml of a buffer [50 mM Tris-HCl (pH 8.0) and 50 mM EDTA]. Subsequently, it was treated with 400 μg/ml of lysozyme (produced by Seikagaku Kogyo), and 10 μg/ml of ribonuclease A (produced by Sigma Co.) at 37° C. for 15 minutes, to which were then added 70 ml of a buffer (50 mM Tris-HCl (pH 8.0) and 50 mM EDTA). Next, it was treated with 0.5% of sodium dodecylsulfate (SDS) and 50 μg/ml of proteinase K (produced by Sigma Co.) at 65° C. for 30 minutes.
The product was then subjected to extraction twice with phenol and once with phenol-chloroform (1:1). DNA was precipitated with ethanol, and then dissolved in 5 ml of TE buffer (10 mM Tris-HCl (pH 8.0), 1 mM EDTA). The solution was treated with 100 μg of ribonuclease A at 37° C. for 1 hour, and then subjected to extraction once with phenol and with phenol-chloroform (1:1). DNA was precipitated with ethanol, then dissolved in 2 ml of TE buffer. The solution was then dialyzed against 1 liter of TE buffer. 360 μg of chromosomal DNA was obtained
(ii) Preparation of a cosmid library
The chromosomal DNA (11 μg) obtained in (i) was partially digested to ca. 40 kb with a restriction enzyme Sau3AI. The DNA fragments obtained were ligated with 4.2 μg of BamHI-cleaved cosmid pJB 8 arm (Amersham) by a T4 ligase. The DNA was in vitro packaged into λ particles by means of in vitro packaging kit (Amersham), and was used to transfect E. coli DHI (F - , gyr A96, rec Al, rel Al? , end Al, thi-1, hsd R17, sup E44, λ-) [J. Mol. Biol., 166, 557-580 (1983)] to obtain a cosmid library.
(iii) Screening of an α-ALDCase gene carrying strain
An α-ALDCase gene carrying strain was obtained by selecting strain which exhibits α-ALDCase activity from the cosmid library obtained in (ii).
Specifically, 600 strains from the cosmid library were respectively inoculated into an L-broth containing 50 μg/ml of ampicillin and 0.5% of glucose and aerobically cultivated overnight at 37° C., and α-ALDCase activity was measured for each culture. In other words, collected cells were suspended in a 30 mM potassium phosphate buffer (pH 6.2). Toluene (10 μl) was added to the cell suspension, and the suspension was vigorously mixed by vortexing for 30 seconds. The α-ALDCase activity of the cell suspension was evaluated according to the method of Godfredsen et al. [Carlsberg Res. Commun., 47, 93 (1982)]. As a result, two α-ALDCase activity carrying strains were obtained. The plasmids of the clones obtained were respectively designated as pAX1 and pAX2.
(iv) Determination of the DNA base sequence in α-ALDCase gene
Subcloning of the α-ALDCase gene was carried out by the method schematically illustrated in FIG. 3. First, the DNA fragment which was obtained by the partial digestion of pAXl with Sau3AI was inserted into the BamHI site of pUC12 (Pharmacia). One of the plasmids thus obtained exhibited α-ALDCase activity in E. coli and contained a chromosomal DNA fragment of 3.6 kb. The plasmid was designated pAXSll. A fragment of ca. 1260 bp excised from the pAXSll with KpnI and SacI was inserted between the KpnI site and the SacI site of pUC19 (Takara Shuzo) to obtain a plasmid (pAX6). The E. coli carrying the pAX6 exhibited α-ALDCase activity.
The DNA base sequence (from the base at the position 1 to the base at the position 1252 in FIG. 1) of the KpnI-Sau3AI fragment contained in the pAX6 was determined by the dideoxy method [Proc. Natl. Acad. Sci. USA, 74, 5463 (1977)]. As the result of the analysis of the base sequence, it was found that the fragment contained an open reading frame of 912 bp which was capable of coding for a protein having a molecular weight of 33,747.
(2) Introduction of the α-ALDCase gene into yeast (Part 1)
(i) Acquirement of the GPD promoter
A chromosomal DNA was prepared in a usual manner from Saccharomyces cerevisiae S288C [(α, suc2, mal, ga12, CUPl): Biochem. Biophys. Res. Commun., 50 1868 (1973): ATCC26108]. The DNA was partially digested with Sau3AI under such a condition as to primarily produce fragments of ca. 10 kb and then cloned into BamHI site of the plasmid pBR322 (Takara Shuzo) to obtain a library.
A synthesized oligomer corresponding to the bases region of the GPD gene [J. Biol. Chem., 254, 9839 (1979)]was end-labelled with 32P, and the labelled oligomer was used as a probe to obtain a clone containing the GPD gene from the library. The plasmid DNA obtained from the clone was digested with HindIII and a HindIII fragment of ca. 2.1 kb was inserted into a HindIII site of pUC18 (Pharmacia) to obtain plasmid pGPD181. Then, GPD promoter (SalI-BglII) was acquired according to the method illustrated schematically in FIG. 4. First of all, the pGPD181 was cleaved with restriction enzymes HindIII and XbaI to obtain a HindIII-XbaI fragment containing the promoter region of the GPD gene (illustrated by a hatched box in FIG. 4) and a part of the coding region To the HindIII cohesive end of this fragment was ligated synthetic double-stranded DNA having the following nucleotide sequence. This synthetic double-stranded DNA contains the PstI and SphI sites and the cohesive ends of SalI and HindIII. ##STR1##
The HindIII cohesive end was successfully changed into the SalI cohesive end by the addition of the synthetic double-stranded DNA.
Next, this fragment was inserted between the SalI cleavage site and the XbaI cleavage site of the pUC19. The plasmid pGPl thus obtained was digested with XbaI, followed by the Ba131 nuclease digestion to remove completely the coding region and end-filling with Klenow fragment (Takara Shuzo). To this blunt end produced was ligated a synthetic double-stranded DNA of the following nucleotide sequence. (The synthetic double-stranded DNA has a cohesive end of BglII on its one end.) ##STR2##
The blunt end was successfully changed into the BglII terminus by the addition of the synthetic double-stranded DNA. Then the SalI-BglII fragment containing the GPD promoter which was obtained by digesting with SalI was designated as GPD promoter (SalI-BglII) (ii) Acquirement of the PGK terminator
PGK gene [Nucl. Acids Res., 10, 7791 (1982)]was cloned from the library prepared in Example (2)-(i) by the same manner as in Example (2)-(i). As a probe, a synthetic oligonucleotide which corresponded to the nucleotides from position 1 to position 28 in the coding region of the PGK gene and was labelled at the terminus with 32 P was used. The plasmid DNA obtained from this clone was digested with HindIII to obtain a 2.9 kb fragment containing the PGK gene. The fragment was further digested with BglII to obtain a 375 bp BglII-HindIII fragment containing the terminator region of the PGK gene and a part of the coding region. The PGK terminator was prepared from this fragment according to the method illustrated schematically in FIG. 5. First of all, to the BglII cohesive end of the fragment was ligated a synthetic double-stranded DNA of the following sequence. This synthetic double-stranded DNA contains SmaI site and the cohesive ends of SacI and BglII. ##STR3##
Next, the thus obtained SacI-HindIII fragment containing PGK terminator region was inserted between the HindIII site and the SacI site of pUC12 to construct plasmid pPGl. The pPGl was then digested with HindIII and treated with Klenow fragment to make a blunt end. To this blunt end was ligated a synthetic double-stranded DNA of the following nucleotide sequence, which synthetic double-stranded DNA contains the cohesive end of SalI. ##STR4##
Plasmid pPG2 was constructed by the re-ligation after addition of the synthetic DNA. A SacI-SalI fragment containing a terminator part can be prepared from pPG2 by the SacI and SalI digestions. This fragment was designated PGK terminator (SacI-SalI).
(iii) Construction of an expression plasmid and its introduction into yeast
Plasmid pAX43 which expresses an α-ALDCase gene in yeast was constructed according to the method illustrated schematically in FIG. 6. First, the plasmid pAX6 constructed in Example (1)-(iv) was digested with KpnI and SacI to obtain an about 1260 bp KpnI-SacI fragment containing the α-ALDCase gene. This fragment was partially digested with RsaI to obtain a 1.02 kb RsaI-SacI fragment containing the α-ALDCase gene illustrated in FIG. 1. This fragment was inserted between the SmaI and SacI sites to construct plasmid pAX31. This plasmid was digested with BamHI and SacI to obtain a BamHI-SacI fragment containing the α-ALDCase gene, which fragment contains the nucleotide sequence from position 243 to position 1252 of the nucleotide sequence illustrated in FIG. 1 and a partial nucleotide sequence of the vector. Three fragments, i.e. this fragment, the GPD promoter (SalI-BglII) obtained in (2)-(i) and the PGK terminator (SacI-SalI) obtained in (2)-(ii), were inserted between the XhoI and SalI sites of the plasmid YEp13K (described in detail hereinafter) to construct the expression plasmid pAX43 (FIG. 2). This plasmid pAX43 was introduced into a yeast [a TD4 (a, his, ura, leu, trp) strain which is a mutant of Saccharomyces cerevisiae S288C]by the lithium acetate method [J. Bacteriol., 153, 153, 1983)]. The TD4 strain containing pAX43 obtained in such a way is referred to as YAL12.
The plasmid YEp13K was prepared in such a procedure as follows by using basically plasmid YEp13 replicable in yeast [Gene, 8, 121 (1979)].
First of all, the SalI-SacI fragment and the XhoI-SmaI fragment which were placed at either end of the LEU2 of the plasmid YEp13 were removed. By this procedure, the plasmid obtained had no cleavage sites for restriction enzymes XhoI, SacI, SmaI and BglII, but had only one cleavage site for restriction enzyme SalI. Next, the synthetic oligonucleotide 41mer was inserted into the plasmid between the cleavage site of restriction enzyme HindIII derived from pBR322 and the cleavage site of restriction enzyme HindIII derived from 2μm DNA. This synthetic oligonucleotide had cleavage sites of restriction enzymes SacI, SmaI, BglII and XhoI and also possessed the following base sequence, the resultant plasmid being designated YEp13K. ##STR5##
(iv) Expression of the α-ALDCase gene in yeast
The TD4 oontaining YEp13K and a YAL2 (TD4 strain containing pAX43) were respectively cultured overnight in the selection medium [0.7% amino acid free yeast nitrogen base (manufactured by DIFCO Co.), 2% glucose, 20 mg/lit histidine, 20 mg/lit tryptophan, 20 mg/lit uracil], and then their α-ALDCase activities were measured. The results are shown in the following table.
The α-ALDCase activity of yeast was measured by the method described by Godfredsen et al. wherein bacterial cells ground by means of glass beads were used as an enzyme solution. lU of the activity means the amount of an enzyme which will produce 1 μmole acetoin per hour. The amount of protein of the enzyme solution was determined with a Protein Assay Kit (manufactured by Bio-Rad Co.).
The α-ALDCase is expressed as the unit per protein amount in the enzyme solution (U/mg protein)
______________________________________ALDCase activity of YAL2 α-ALDCase activityStrain (U/mg protein)______________________________________TD4 + YEp 13K 1 0 2 0 Average 0YAL2 1 2.50(TD4 + pAX43) 2 3.27 3 3.68 4 3.47 Average 3.23______________________________________
(3) Introduction of the α-ALDCase gene into yeast (Part 2)
(i) Acquirement of the ADHl promote
A clone containing the ADHl gene was obtained from the library prepared in Example (2)-(i) by using as a probe a 32P terminus labelled synthetic oligonucleotide which corresponded to the bases from position 7 to position 36 in the coding region of the ADHl gene [J. B. C., 257, 3018 (1982)]. The DNA fragment obtained from this clone was partially digested with a restriction enzyme Sau3AI to obtain the 1.5 kb DNA fragment containing a part of the coding region and the promoter of ADHl gene.
This fragment was inserted into the BamHI site of plasmid pUC18 (Pharmacia), and the plasmid obtained was designated pADHSl. The BamHI site of the pUC18 is placed between the XbaI and SmaI of pUC18, and thus the DNA fragment inserted into the BamHI site can be excised by digestion with XbaI and SmaI. After the plasmid pADHSl had been digested with XbaI, it was treated with an endonuclease Ba131 to remove completely the coding region of the ADHl gene and HindIII linkers (Takara Shuzo) were ligated to the fragment. Then, after digesting with SmaI, BamHI linkers were ligated to the fragment The resultant BamHI-HindIII fragment was used as ADHl promoter
The ADHl promoter was inserted between the BmaHI and HindIII sites in YEp13K to obtain the plasmid pYADH.
(ii) Expression of the α-ALDCase gene
After pAX6 had been digested with restriction enzyme XbaI, it was treated with a Klenow fragment to make a blunt end, and plasmid pAX6Bg was prepared by linking BglII linkers (Takara Shuzo) and re-ligation. From this pAX6Bg, the HaeIII-BglII fragment (containing a base sequence from position 180 to position 1252 of the base sequence illustrated in FIG. 1 and a part of the vector) which contained the ALDCase gene was obtained (referred to hereinafter as fragment 1).
After the SacI terminus of the RsaI-SacI fragment obtained in Example (2)-(iii) was treated with a Klenow fragment to form a blunt end, BglII linkers were ligated to it. This RsaI-BglII fragment (containing a base sequence from position 243 to position 1252 of the base sequence illustrated in FIG. 1 and a part of the vector) was designated fragment 2. From the pAX6Bg, the HindIII-BglII fragment (containing a base sequence from position 345 to position 1252 of the base sequence illustrated in FIG. 1 and a part of the vector) which contained a part of the α-ALDCase gene was also obtained (referred to hereinafter as fragment 3).
The plasmid pYADH was digested with HindIII and treated with Klenow fragment to form a blunt end, and it was further digested with BglII. This fragment was linked to the aforementioned fragment 1 or 2 to prepare plasmids pAX39 (in the case of fragment 1) and pAX40 (in the case of fragment 2), respectively. The fragment 3 was inserted between the HindIII and BglII sites of pYADH to prepare a plasmid pAX41.
The plasmids pAX39, pAX40 and pAX41 can produce polypeptides which are encoded by the fragments 1, 2 and 3, respectively, with the use of the ADHl promoter These pAX39, pAX40 and pAX41 were respectively used to transform TD4, and the α-ALDCase activities of the transformants obtained were measured The results are shown in the following table.
______________________________________Comparison of α-ALDCase activitiesStrain Ratio of α-ALDCase activities______________________________________TD4 + YEp13K 0TD4 + pAX39 69TD4 + pAX40 100TD4 + pAX41 0______________________________________
The polypeptide encoded in the fragment 2 is the polypeptide which is illustrated as the part from A 2 to B in FIG. 1. The polypeptide encoded in the fragment 1 is a polypeptide which is illustrated as the part from A 1 to B in FIG. 1.
The polypeptide obtained by the expression of the fragment 3 showed no α-ALDCase activity It was supposedly attributed to the reason that only a short peptide comprising amino acids corresponding to the base sequence from position 352 to position 372 in FIG. 1 is presumably produced (the ATG from position 352 to position 354 is suspected to be a translation initiating codon and the TGA from position 373 to position 375 to be a terminating codon), and this peptide was quite different from the α-ALDCase, so that it showed no α-ALDCase activity.
(4) Introduction of the α-ALDCase qene into yeast (Part 3)
Expression of the DNA sequence which codes for α-ALDCase which has an amino acid sequence of a part from A to B in FIG. 1 and to which several amino acids have been added.
(i) Introduction
Referring in detail to the base sequence illustrated in FIG. 1, some ATG's or GTG's are present upstream to and in the same reading frame as the nucleotide sequence coding for the α-ALDCase. These ATG and GTG codons are possible translation initiation points. They are underlined and are numbered 1 to 7. Any one of these codons may be selected for use as translation initiation point. Translation will start at the selected point so that a protein is produced in yeast having an amino acid sequence represented by the sequence from A to B in FIG. 1 to the N-terminus of which several amino acids have been added. The exact number of the extra amino acids is dependent on which ATG is chosen as the translation start point. When GTG codon is selected, it is necessary to convert it to ATG, as GTG is not recognized as an initiation codon in yeast. The number of amino acids to be added depends upon which ATG or GTG is selected as the translation initiation point. α-ALDCase polypeptide with extra amino acids were produced by the methods specified in section (ii) to (v) below, and it was proved that these polypeptides have α-ALDCase activities.
(ii) Introduction of a new restriction site into pAX6 by a site specific mutagenesis method (resulting in the construction of 5 plasmids designated pALDCl-5)
Oligonucleotides A-E shown in Table 1 were synthesized.
TABLE 1__________________________________________________________________________ MutagenizedOligonucleotide Nucleotide sequence plasmid Expression plasmid__________________________________________________________________________ ##STR6## ##STR7## pALDC1 pAX50A ##STR8##B ##STR9## pALDC2 pAX50B ##STR10##C ##STR11## pALDC3 pAX50C ##STR12##D ##STR13## pALDC4 pAX50D ##STR14##E ##STR15## pALDC5 pAX50E__________________________________________________________________________
Five (5) pairs of the nucleotide sequence are shown in Table 1. The nucleotide sequences of the synthesized oligonucleotides to be used for site-specific mutagenesis are shown in the lower row of each pair. The nucleotide sequences of pAX6 to be mutagenized with these oligonucleotides are shown in the upper rows. The nucleotide sequences to be mutagenized include some of possible translation start points which are underlined and numbered 1 to 5 in FIG. 1. The nucleotide sequences in the lower rows are the same as the modified nucleotide sequences obtained after the mutation, wherein the nucleotides modified are shown with a dot (·) added. The mutation creates DraI cleavage site immediately upstream to the codons which are underlined and numbered 1 to 5 in FIG. 1. Further, when the underlined codon is GTG, it was converted into ATG. The plasmid pAX6 was mutagenized by means of these oligonucleotides shown in Table 1 by site-specific mutagenesis (Morinaga, Y. et al., Bio/Technology, 2, 636-639 (1984)) as outlined in FIG. 7. The names of mutated plasmids and expression plasmids constructed therefrom are set forth in Table 1. Construction of the expression plasmids are described in detail in Example (iv). A fragment containing α-ALDCase gene was excised from the mutated plasmid with DraI+SacI.
(iii) Creation of new restriction sites in pAX6 by means of a synthesized double stranded DNA (Construction of pALDC6 and 7)
Two double stranded DNAs, F and G, shown in Table 2 were synthesized.
TABLE 2__________________________________________________________________________ PlasmidsDNA Nucleotide sequence constructed__________________________________________________________________________ F##STR16## pALDC6 G##STR17## pALDC7__________________________________________________________________________
These synthesized DNAs have nucleotide sequences from either of the underlined portion 6 or 7 in FIG. 1 to the NcoI cleavage site, and have DraI cleavage site immediately upstream to the portion 6 or 7 underlined. These DNAs also have the cohesive ends of HindIII and NcoI. The DNA fragment from the HindIII site which originated from pUC19 to the NcoI site in the α-ALDCase gene was removed from pAX6. Then, the synthesized DNA, F or G, was ligated to the remnant part of pAX6. The resulting plasmids were designated pALDC6 and pALDC7, respectively. The fragments containing the α-ALDCase gene were excised with DraI+SacI from pALDC6 and pALDC7, respectively.
(iv) Acquirement of GPD promoter
According to the method outlined in FIG. 8, GPD promoter (BamHI-HindIII) was acquired.
First, pGPD181 constructed in Example (2)-(i) was cleaved with XbaI, followed by Ba131 digestion to completely remove the coding region and treatment with Klenow fragment. To the blunt end was linked HindIII linker (Takara Shuzo, Japan), and the product was then digested with HindIII to excise the fragment containing the promoter region. The fragment was then inserted into the HindIII cleavage site of pUC18. The plasmid thus constructed is in two types in view of the orientation of the HindIII fragment inserted, and the plasmid in which the multiple cloning site which originated from pUC18 was located upstream from the GPD promoter was designated pST18. The pST18 was partially digested with HindIII, treated with Klenow fragment and re-ligated. Among the plasmids thus constructed, one which had the HindIII cleavage site upstream from the GPD promoter destroyed was designated plasmid pST18H. The fragment containing the GPD promoter, which was excised from the pST18 with BamHI and HindIII, was designated GPD promoter (BamHI-HindIII).
(v) Acquirement of PGK terminator
According to the method outlined in FIG. 9, PGK terminator (HindIII - SalI) was obtained.
First, the synthesized double stranded DNA of the following nucleotide sequence was inserted between EcoRI cleavage site and SacI cleavage site of pPG2 constructed in Example (2)-(ii) to construct plasmid pPG3, which synthesized double stranded DNA had HindIII and SphI cleavage sites and had cohesive ends of EcoRI and SacI. ##STR18##
Digestion of pPG3 with HindIII and SalI produced HindIII-SalI fragment containing pGK terminator region, which was designated PGK terminator (HindIII-SalI). (vi) Construction of expression plasmid:
The method used is outlined in FIG. 10.
First, the GPD promoter (BamHI-HindIII) obtained in Example (4)-(iv) and the PGK terminator (HindIII-SalI) obtained in Example (4)-(v) were inserted between the BglII cleavage site and SalI cleavage site in the plasmid YEP13K to construct plasmid pSY114P.
The plasmid pSY114P is capable of expressing a gene in yeast by means of the GPD promoter and the PGK terminator, which gene has been inserted in it in specified orientation between the HindIII cleavage site and SacI cleavage site. From each of pALDCl, pALDC2, pALDC3, pALDC4 and pALDC5, five DraI-SacI fragments containing the α-ALDCase gene were excised. pSY114P was digested with HindIII, and was then treated with mungbean nuclease (Takara Shuzo, Japan) thereby to remove the cohesive termini. The fragment obtained was then processed by Klenow fragment, followed by digestion with SacI. The fragment thus obtained was then ligated to each of the five DraI-SacI fragments containing the α-ALDCase gene as referred to hereinabove to construct five plasmids: pAX50A, pAX50B, pAX50C, pAX50D, and pAX50E. These plasmids respectively contain the α-ALDCase gene originated from pALDCl, pALDC2, pALDC3, pALDC4 and pALDC5 and capable of expressing the α-ALDCase gene in yeast.
On the other hand, the HindIII-SacI fragments containing the α-ALDCase were excised respectively from pALDC6 and pALDC7, and inserted between the HindIII cleavage site and the SacI cleavage site of pY114P to construct expression plasmids: pAX50F2 and pAX50G2. The pAX50F2 and pAX50G2 contain the u-ALDCase gene originated respectively from pALDC6 and pALDC7.
When α-ALDCase genes of above-mentioned expression plasmids were expressed in yeast, the translation start points and the polypeptides produced are assumed to be as follows.
______________________________________Expression Translation initiation Polypeptideplasmid site encoded______________________________________pAX50A Portion 1 underlined A.sub.1 to B in FIG. 1 in FIG. 1pAX50B Portion 2 underlined A.sub.2 to B in FIG. 1 in FIG. 1pAX50C Portion 3*.sup.1 underlined A.sub.3 to B*.sup.2 in FIG. 1 in FIG. 1pAX50D Portion 4 underlined A.sub.4 to B*.sup.2 in FIG. 1 in FIG. 1pAX50E Portion 5*.sup.1 underlined A.sub.5 to B*.sup.2 in FIG. 1 in FIG. 1pAX50F2 Portion 6*.sup.1 underlined A.sub.6 to B*.sup.2 in FIG. 1 in FIG. 1pAX50G2 Portion 7 underlined A to B in FIG. 1 in FIG. 1______________________________________ *.sup.1 GTG has been converted into ATG *.sup.2 Val in the Nterminus is replaced by Met
(vii) Expression in yeast
Laboratory yeast TD4 was transformed with the seven expression plasmids: pAX50A to E, pAX50F2 and pAX50G2, constructed in Example (4)-(vi).
The α-ALDCase activities of the transformants obtained were determined by the same method as in Example (2)-(iv).
The results obtained are set forth in the following Table, wherein it is shown that every transformant containing the expression plasmid exhibited α-ALDCase activity.
______________________________________ α-ALDCase activityStrain tested Polypeptide encoded (U/mg-protein)______________________________________TD4 + YEp13K -- 0TD4 + pAX50A A.sub.1 to B in FIG. 1 2.7TD4 + pAX50B A.sub.2 to B in FIG. 1 6.9TD4 + pAX50C A.sub.3 to B* in FIG. 1 18.0TD4 + pAX50D A.sub.4 to B in FIG. 1 21.2TD4 + pAX50E A.sub.5 to B* in FIG. 1 35.2TD4 + pAX50F2 A.sub.6 to B* in FIG. 1 17.0TD4 + pAX50G2 A to B in FIG. 1 35.8______________________________________ *Val at the Nterminus is replaced by Met.
(5) Confirmation in fermentation test of reduction in diacetyl formation
(i) Construction of an expression vector for beer yeast, pAX43KL
The method used is outlined in FIG. 11.
First, ADHl promoter +lacZ gene which is capable of expressing β-galactosidase in yeast was obtained as follows. Thus, lacZ gene (E. coli β-galactosidase gene) was obtained as a BamHI fragment from plasmid pMC1871 (Pharmacia). This fragment (lacZ gene) lacks the promoter and translation start points. This fragment was inserted into BglII site of plasmid YEp13K in the direction indicated by the arrow in FIG. 11 to construct the plasmid placZl. The lacZ gene in placZ acquired the new translation start codon (ATG) which located in the same reading frame as lacZ between BglII and HindIII sites originated in YEp13K. The ADHl promoter obtained in Example (3)-(i) was inserted between BamHI and HindIII sites of placZl to construct the plasmid pADHl-lacZ in which the ADHl promoter was used to express lacZ. The pADHl-lacZ was digested with XhoI, and was then processed
It was confirmed that TDA concentration in wort fermented by YAL3-1 or YAL3-2 was significantly lower than that in wort fermented by the control strain.
______________________________________ Apparent*.sup.1 TDA*.sup.2Yeast tested attenuation (mg/lit)______________________________________Beer yeast (1) 72.6 0.99Beer yeast (2) 72.6 1.00Average 72.6 1.00Beer yeast + pAX43XL (1) 72.3 0.28(YAL3-1)Beer yeast + pAX43XL (2) 72.3 0.33(YAL3-1)Average 72.3 0.31Beer yeast + pAX43XL (1) 75.4 0.32(YAL3-2)Beer yeast + pAX43XL (2) 75.4 0.26(YAL3-2)Average 75.4 0.29______________________________________ *.sup.1 Apparent attenuation is defined as follows. Apparent attenuation (%) = [Original wort extract (°P) apparent extract of the fermented wort (°P)] × 100/[Original wort extract *.sup.2 TDA comprises vicinal diketones and acetohydroxylic acid (mainly DA and its precursor, i.e. AL).
(6) Introduction of the α-ALCDase gene into yeast (Part 4)
Integration of the α-ALDCase gene into a yeast chromosome, expression and fermentation test
(i) Outline of the method of integrating the α-ALDCase gene into the yeast chromosome
The α-ALDCase gene which had been capable of expression in yeast by the addition of the GPD promoter with Klenow fragment, followed by addition of SalI linker (Takara Shuzo, Japan). From the fragment ADHl promoter +lacZ gene was then excised as a BamHI-SalI fragment. G418 resistant gene, on the other hand, was excised from pUC4K (Pharmacia) as a SalI-BamHI fragment by partial digestion with SalI and complete digestion with BamHI. This fragment containing the G418 resistant gene and the BamHI-SalI fragment containing ADHl promoter +lacZ gene referred to above were inserted into the SalI cleavage site of pAX43 constructed in Example (2)-(iii) to construct plasmid pAX43KL (FIG. 12).
(ii) Introduction of pAX43KL into beer yeast
A conventional beer yeast was transformed with the pAX43KL according to the lithium acetate method. The G418-resistant colonies having β-galactosidase activity were selected as the real transformants. These transformants exhibited the α-ALDCase activity of 3.2 to 7.0 U/mg protein. Two independent strains among the transformants were respectively designated YAL3-1 and YAL3-2.
(iii) Fermentation test
YAL3-1 and YAL3-2 obtained in Example (ii) were cultured statically in 50 ml of wort containing 10 ppm of G418 at 20° C. for 3 days. The whole cultures were added to 1 liter of wort containing 10 ppm of G418, and further cultured statically at 8° C. for 10 days. Then, cells were collected by centrifugation (5000 rpm, 10 min.). The cells obtained were used to inoculate wort of 11° P. (plato) at inoculum level of 0.5% (0.5 g wet cells/100 ml wort). After sufficient aeration, fermentation was conducted at 8° C. for 8 days. After completion of fermentation, cells were removed by centrifugation and filtration with a filter paper. Then, the amount of TDA (total diacetyl) and apparent attenuation degree of the fermented wort were determined.
The results obtained are set forth in the following Table. and the PGK terminator was inserted into the yeast rRNA gene to prepare a fragment illustrated in FIG. 13. This fragment was transformed together with a YEp type plasmid carrying the G418 resistant gene into yeast, and the G418-resistant transformants were selected. Among these transformants, a transformant such that the aforementioned α-ALDCase gene had been integrated into the rRNA gene of the yeast chromosome by homologous recombination was successfully obtained.
(ii) Construction of the integration type plasmid (pAX60G2)
Plassmid pAX60G2 which has no replication origin in yeast and can be carried on yeast only when it is integrated into the chromosome (of the yeast) was constructed according to the method illustrated schematically in FIG. 15.
First, the EcoRI cleavage site of plasmid pUC12 (Pharmacia) was treated with Klenow fragment, and XhoI linkers (Takara Shuzo) were further added. Then, the plasmid was subjected again to ligation. This plasmid possesses a new XhoI cleavage site, and in the same time the EcoRI cleavage sites regenerated at the both sides of the XhoI cleavage site. This plasmid was cleaved with XbaI, treated with a Klenow fragment and then subjected to ligation again. The plasmid pUC12EX thus obtained contains no XbaI cleavage site.
An oligonucleotide was synthesized which corresponded to the nucleotide sequence from position 4 to position 32 at the 5'-terminal region of a 5.8S rRNA gene [J. Biol. Chem. 252, 8118-8125 (1977)]. After being labelled with 32 P at the 5'-terminus, this was used as a probe to isolate rRNA genes from the library prepared in Example (2)-(i).
A 3 kb EcORI fragment was excised from the isolated rRNA genes. This fragment contained a part of the 5.8S rRNA gene and a part of the 2.8S rRNA gene. This fragment was treated with Klenow fragment before addition of XhoI linkers. The fragment was then inserted into the XhoI site of the plasmid pUC12EX.
Moreover, plasmid pAX50G2 constructed in (4)-(vi) was cleaved with SalI, and a fragment containing the GPD promoter, the α-ALDCase gene and the PGK promoter (this fragment is illustrated by the hatched box in FIG. 15) was obtained. The fragment was treated with Klenow fragment, followed by ligation to XbaI linker (Pharmacia). Then, the XbaI fragment was inserted into the XbaI cleavage site of the pIR xh0 to construct plasmid pAX60G2.
(iii) Construction of YEp type plasmid pAS5 containing the G418 resistant gene
Plasmid pAS5 was constructed according to the method illustrated schematically in FIG. 16.
First, the fragment containing the G418-resistant gene (G418r) was excised with BamHI from the plasmid pUC4K (Pharmacia) and inserted into the BamHI cleavage site of pADHl-lacZ obtained in (5)-(i). Among the plasmids thus obtained, one into which two G418 resistant genes had been inserted was designated pAS5. The degree of resistance to G418 was greater when the plasmid pAS5 was used for transformation than when a plasmid containing one G418, gene was used.
(iv) Integration of the α-ALDCase gene into a yeast chromosome DNA:
Beer yeast IFO 0751 was co-transformed by the lithium acetate method with the fragment which was obtained by the EcoRI digestion of pAX6uG2 obtained in (ii) (i.e. the fragment in FIG. 13) and pAS5 obtained in (iii) (FIG. 14). G418 resistance and β-galactosidase activity were used as markers to select transformants. A transformant thus obtained was cultured aerobically in YPD medium at 30° C. overnight, and then strains having the α-ALDCase gene were obtained by measuring the α-ALDC activity. These strains were subcultured non-selectively for 12-13 generations in YPD medium, and then the appropriately diluted cultures were respectively plated on Ruby's agar media containing X-gal (5'-bromo-4'-chloro-3'-indolyl-β-D-galactoside) [Method in Enzymology, vol, 101, 253 (1983)]. These plates were incubated at 30° C. for 3-5 days, and colonies not exhibiting blue color that is, strains showing no β-galactosidase activity were obtained. It is believed that these strains do not have PAS5, but have only the α-ALDCase expression unit integrated into chromosome DNA which consists of the GPD promoter, the α-ALDCase gene and the PGK terminator. These strains had been cultured aerobically in the YPD medium at 30° C. overnight, and then the α-ALDCase activity was measured. Among these strains, one which exhibits ALDCase activity of 1.0 U/mg protein is designated YAL4. When YAL4 was subcultured for 47 generations in YPD medium, the α-ALDCase activity was maintained at a level of 75% or more.
(v) Fermentation test
The YAL4 obtained in (iv) was cultured statically in 50 ml of wort at 20° C. for 3 days, and the whole culture was used to inoculate 1 liter of wort to continue static culture at 10° C. for 10 days. Yeast cells thus grown up were collected by centrifugation (5,000 rpm ×10 min). The yeast cells thus obtained were used to inoculate wort of 11° P. at inoculum level of 0.6% (wet W/V). This culture was aerated sufficiently by stirring, and then static fermentation was conducted at 10° C. for 10 days. After completion of fermentation, the yeast cells were removed by centrifugation and filtration with a filter paper, and the amount of TDA (total diacetyl) and apparent attenuation degree of the fermented wort were measured. Results are shown in the following table. It was found that the amount of TDA was decreased in the fermentation with the yeast of the present invention as compared with a fermentation with a control strain.
______________________________________ Apparent TDAStrain attenuation degree (mg/lit)______________________________________IF00751 1 74.4 0.95 2 72.8 1.04 Average 73.6 1.00YAL4 1 73.8 0.46 2 71.7 0.50 Average 72.8 0.48______________________________________
Deposition of microorganism
The strain YAL2 was deposited at Fermentation Research Institute, Agency of Industrial Science and Technology at 1-3, Higashi 1 chome, Yatabe-machi, Tsukuba-gun, Ibaraki-ken, 305, Japan on Apr. 7, 198 under an accession number of FERM BP-1844.
The plasmid pAX6 containing the DNA fragment in accordance with the present invention was deposited as E. coli JM109 (containing pAX6), which is E. coli JM109 (Takara Shuzo, Japan) harboring the pAX6, at the Fermentation Research Institute on Dec. 14, 1988 under an accession number of FERM BP-2187.
The strain YAL4 was deposited at the Fermentation Research Institute on Apr. 7, 1989 under an accession number of FERM BP-2374.
These deposits are under the Budapest Tready on the international recognition of the deposit of microorganisms for the purpose of patent procedure. | DNA strand having an ability in biotechnological production of α-acetolactate decarboxylase is disclosed. The DNA strand is characterized in that it has a nucleotide sequence coding for a polypeptide whose amino acid sequence is substantially from A to B of FIG. 1 and which has α-acetolactate decarboxcylase activity. Also disclosed is a yeast which belongs a Saccharomyces cerevisiae and which has been transformed by the DNA strand. The yeast is characterized by the fact that its α-acetolactate producing ability is reduced, and will thus produce an alcoholic liquor such as beer which contains no or little diacetyls which have come from their precursor, namely α-acetolactate. | 2 |
BACKGROUND
The present invention relates generally to operations performed and equipment utilized in conjunction with subterranean wells and, in an embodiment described herein, more particularly provides equipment and methods for use in underbalanced well completions.
At times it is useful to be able to isolate a portion of a tubular string, such as a production tubing, drill pipe, liner or casing string, from the remainder of the tubular string. For example, while drilling underbalanced, it is useful to be able to periodically trip a drill string in and out of the well without killing the well. In that instance, a valve may be interconnected in a casing string, the valve being opened upon tripping in the drill string, and the valve being closed when the drill string is tripped out of the well. A valve suitable for such an application is described in U.S. Pat. No. 6,152,232, the entire disclosure of which is incorporated herein by this reference.
Other uses include running completion assemblies (including perforated or slotted liners) after drilling underbalanced, drilling overbalanced in areas of lost circulation to prevent kicks and loss of mud while tripping the drill string, and drilling in deep water where pore pressure and fracture gradient provide a narrow window for acceptable mud density and use of lower mud density is desired.
From the foregoing, it can be seen that it would be quite desirable to provide improvements in underbalanced well drilling and completions, in other operations, and in equipment utilized in these operations.
SUMMARY
In carrying out the principles of the present invention, in accordance with an embodiment thereof, an apparatus is provided which is an improvement over prior equipment utilized in the operations described above.
In one aspect of the invention, a well system is provided. The well system includes an apparatus positioned in a well and a tool conveyed through the apparatus in a container. The container engages the apparatus, actuating the apparatus and separating from the tool, as the tool is displaced through the apparatus.
In another aspect of the invention, an apparatus for use in a subterranean well in conjunction with a tool conveyed through the apparatus in a container is provided. The apparatus includes an engagement device which engages the container, preventing relative displacement between the container and the apparatus, as the tool is conveyed through the apparatus.
In yet another aspect of the invention, a valve for use in a subterranean well in conjunction with a tool conveyed through the valve in a container is provided. The valve includes a passage formed longitudinally through the valve, a closure assembly which selectively permits and prevents flow through the passage, and an engagement device which engages the container as the tool is conveyed through the passage. The closure assembly permits flow through the passage when the container is conveyed into the passage, and the closure assembly prevents flow through the passage when the container is removed from the passage. Engagement between the container and the engagement device separates the tool from the container.
These and other features, advantages, benefits and objects of the present invention will become apparent to one of ordinary skill in the art upon careful consideration of the detailed description of a representative embodiment of the invention hereinbelow and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic partially cross-sectional view of a well system embodying principles of the present invention;
FIG. 2 is a cross-sectional view of an apparatus used in the well system of FIG. 1 , the apparatus embodying principles of the invention, and the apparatus being depicted in an initial configuration;
FIG. 3 is a cross-sectional view of the apparatus depicted in a configuration in which an engagement device of the apparatus has engaged a container containing a tool being conveyed through the apparatus; and
FIG. 4 is a cross-sectional view of the apparatus depicted in a configuration in which the tool is being used to cut through a portion of the container.
DETAILED DESCRIPTION
Representatively illustrated in FIG. 1 is a well system 10 which embodies principles of the present invention. In the following description of the system 10 and other apparatus and methods described herein, directional terms, such as “above”, “below”, “upper”, “lower”, etc., are used only for convenience in referring to the accompanying drawings. Additionally, it is to be understood that the various embodiments of the present invention described herein may be utilized in various orientations, such as inclined, inverted, horizontal, vertical, etc., and in various configurations, without departing from the principles of the present invention.
As depicted in FIG. 1 , the system 10 includes an apparatus 12 interconnected in a tubular string 14 positioned in a wellbore 16 . Representatively, the apparatus 12 is a valve which selectively permits and prevents flow through an interior passage 18 of the string 14 , and the string is a casing string cemented in the wellbore 16 . However, it should be clearly understood that the invention is not limited to these, or any other, specific details of the illustrated system 10 . For example, the casing string 14 could instead be a production tubing string, drill string, etc.
Another tubular string 20 is positioned in the casing string 14 . The tubular string 20 is used in the system 10 to convey a tool 22 through the passage 18 . Representatively, the string 20 is a drill string. However, the string 20 could be another type of conveyance, such as a production tubing string, a wireline, etc., in keeping with the principles of the invention.
The tool 22 could be a drill bit, a perforated or slotted liner, a mud motor, a production tool, a completion tool, a drilling tool, a packer, a multilateral tool, or any other type of well tool. Representatively, the tool 22 is a drill bit used to drill a wellbore extension 24 below the casing string 14 . In this situation, it may be desirable to close the valve 12 while the string 20 is tripped in and out of the wellbore 16 , such as when drilling overbalanced or underbalanced, but the valve would be opened when the drill bit 22 is conveyed therethrough into the wellbore extension 24 for further drilling.
In a unique feature of the invention, the drill bit 22 is conveyed in a container 26 attached to the drill string 20 . As the container 26 is conveyed into the valve 12 , the container engages the valve, operates the valve to open a closure assembly 28 of the valve, and then the container disengages from the tool, allowing the tool 22 to be conveyed into the wellbore extension 24 on the drill string 20 , without the container.
One advantage of this system lo is that the container 26 may be configured so that it can accommodate a variety of tools, and so a different container does not have to be constructed for each tool conveyed through the valve 12 . For example, the container 26 may be used to convey the drill bit 22 through the valve 12 during drilling operations, and then the same or a similar container may be used to convey an item of completion equipment (such as a packer, etc.) through the valve after drilling operations are completed.
Referring additionally now to FIG. 2 , an enlarged cross-sectional view of the valve 12 is representatively illustrated. In this view it may be seen that the closure assembly 28 is depicted as including a flapper 30 pivotably supported relative to a seat 32 .
When closed as shown in FIG. 2 , the flapper 30 prevents flow through the passage 18 . However, when pivoted downward about a pivot 34 , the flapper 30 no longer contacts the seat 32 , and flow is then permitted through the passage 18 . Note that other types of closure assemblies may be used in place of, or in addition to, the assembly 28 . For example, the closure assembly 28 could include a ball closure, a sleeve closure, etc.
Referring additionally now to FIG. 3 , the valve 12 is depicted with the drill string 20 conveyed through the casing string 14 . The drill bit 22 is contained within the container 26 , which is shown engaged with the valve 12 . This engagement includes sealing engagement between a sleeve 36 of the container 26 and seals 38 axially straddling the closure assembly 28 , and contact between the sleeve and an internal shoulder 40 formed in the valve 12 which prevents further downward displacement of the sleeve through the passage 18 .
The drill bit 22 is contained in the sleeve 36 between a shoulder 42 formed internally on the sleeve and a plug or abutment 44 closing off a lower end of the sleeve. If desired, the drill bit 22 may additionally be secured relative to the sleeve 36 , for example, using shear screws 46 or another type of securing device. However, preferably the drill bit 22 is permitted to rotate and/or reciprocate within the container 26 .
The abutment 44 may be secured relative to the sleeve 36 using shear screws 48 , or another type of securing device. Preferably, the abutment 44 is made of a tough but relatively easily drillable material, such as a composite material, relatively soft metal, etc. The abutment 44 may be bonded to the sleeve 36 , for example, using adhesives or other bonding agents.
The sleeve 36 could also be made of a composite material (or another relatively easily drillable material), in which case the sleeve and abutment 44 could be molded together, or otherwise integrally formed. If the sleeve 36 is made of a composite material, then the seal surfaces 50 may also be made of a composite material, or another relatively easily drillable material.
As the container 26 is conveyed into the valve 12 , the abutment 44 contacts the closure assembly 28 and pivots the flapper 30 downward, thereby opening the passage 18 . Damage to the flapper 30 and seat 32 is prevented in part by the abutment 44 being made of the relatively easily drillable material.
The sleeve 36 then enters and maintains the flapper 30 in its opened position. Again, damage to the flapper 30 and seat 32 may be prevented by the sleeve 36 being made of the relatively easily drillable material. Sealing engagement between the seals 38 and seal surfaces 50 formed externally on the sleeve 36 isolates the closure assembly 28 from debris, etc. in the passage 18 .
For example, during drilling operations this sealing engagement may prevent cuttings from becoming lodged in the closure assembly 28 . The sleeve 36 , or a similar sleeve, may be positioned in the valve 12 while the casing 14 is cemented in the wellbore 16 , in which case the sleeve would prevent cement from contacting the closure assembly 28 .
As described above, a lower end of the sleeve 36 contacts the shoulder 40 , preventing further downward displacement of the sleeve relative to the valve 12 . If the shear screws 46 or other securing devices are used, then at this point a downwardly directed force may be applied to the drill bit 22 (such as by slacking off on the drill string 20 to apply the drill string weight to the bit) in order to shear the screws 46 . However, if the drill bit 22 is not secured to the sleeve 36 (other than being contained between the shoulder 42 and abutment 44 ), then this step is not needed.
Referring additionally now to FIG. 4 , the valve 12 is depicted after the shear screws 46 have been sheared and the drill bit 22 has been displaced downward relative to the sleeve 36 . The drill bit 22 now contacts the abutment 44 .
As illustrated in FIG. 4 , the drill bit 22 is being used to cut through the abutment 44 while the abutment remains attached to the sleeve 36 . This will release the drill bit 22 from within the container 26 , allowing the drill bit and the drill string 20 to displace through the open valve 12 . The alternative configuration depicted in FIG. 4 has the abutment 44 bonded to the sleeve 36 .
However, if the abutment 44 is releasably attached to the sleeve 36 , such as by using the shear screws 48 as depicted in FIG. 3 , then the downward displacement of the drill bit 22 into contact with the abutment 44 may operate to shear the screws and release the abutment from the sleeve. In that case, the drill bit 22 may not cut into the abutment 44 until after the abutment falls (or is pushed) to the bottom of the wellbore extension 24 .
FIG. 4 also depicts another type of engagement device 52 used to provide engagement between the sleeve 36 and the valve 12 . The engagement device 52 includes a snap ring 54 (such as a C-shaped or spiral ring) engaged with a groove 56 formed internally on the valve 12 . The snap ring 54 is preferably carried externally on the sleeve 36 and, when the sleeve is properly positioned relative to the valve 12 , the snap ring snaps into the groove 56 , thereby releasably securing the sleeve relative to the valve. Note that the engagement device 52 may be used as an alternative to, or in addition to, the engagement between the lower end of the sleeve 36 and the shoulder 40 .
After the drill bit 22 has cut through or otherwise released the abutment 44 from the sleeve 36 , the drill bit and drill string 20 are used to drill the wellbore extension 24 . When the time comes to trip the drill string 20 out of the wellbore, or otherwise raise the drill bit 22 back up through the valve 12 , the drill bit will eventually contact the internal shoulder 42 in the sleeve 36 . As the drill bit 22 is raised further, the sleeve 36 will also be raised therewith, and with the sleeve no longer maintaining the flapper 30 in its open position, the closure assembly 28 will close off the passage 18 .
Of course, a person skilled in the art would, upon a careful consideration of the above description of representative embodiments of the invention, readily appreciate that many modifications, additions, substitutions, deletions, and other changes may be made to these specific embodiments, and such changes are contemplated by the principles of the present invention. Accordingly, the foregoing detailed description is to be clearly understood as being given by way of illustration and example only, the spirit and scope of the present invention being limited solely by the appended claims and their equivalents. | Equipment and methods which may be used in conjunction with an underbalanced well completion. In a described embodiment, a valve for use in a subterranean well in conjunction with a tool conveyed through the valve in a container is provided. The valve includes a passage formed longitudinally through the valve, a closure assembly which selectively permits and prevents flow through the passage, and an engagement device which engages the container as the tool is conveyed through the passage. The closure assembly permits flow through the passage when the container is conveyed into the passage, and the closure assembly prevents flow through the passage when the container is removed from the passage. Engagement between the container and the engagement device separates the tool from the container. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to communication antennas and to RF signal transmission through a dielectric barrier. More particularly, it relates to a new and improved glass mount mobile vehicle antenna system employing very high Q, high dielectric constant, low loss dielectric resonators, together with an elevated feed antenna to couple RF energy through the glass via resonance mode coupling of the resonators to minimize coupling losses and to provide an improved omni-directional communication antenna system having high radiation efficiency and low pattern distortion.
Technological advances in personal communication services and products have been astounding. The development of personal paging/beeper systems and mobile cellular telephone systems are prominent examples of these developments. An ultimate technological goal in this field envisions individuals carrying small, inexpensive hand-held communicators and being reachable by voice or data with a single phone number, no matter where they are. This new system, generally referred to as a Personal Communications Network (PCN)/Personal Communications System (PCS), is a wire- less, "go anywhere" communicator system which eliminates the need for separate numbers for the office, home, pager, facsimile or car. Many national and international bodies responsible for regulating communications networks and for working out international communication standards have generally set aside a portion of the ultra-high frequency microwave radio spectrum within the band from about 1.5 GHz to about 2.4 GHz as the bandwidth range dedicated for PCN/PCS communication systems. The present invention is directed to mobile antennas and especially window mounted mobile vehicle antennas for use in any communications system, but which are especially adapted for use in the high frequency operating ranges intended for PCN/PCS communications.
Glass mount mobile antennas for use in cellular mobile telephones, for example, are known which mount on the window of the vehicle, thereby avoiding the need to drill holes in or otherwise modify the vehicle body. Window mounted antennas include an outside module on the outside of the window glass on which a generally vertical radiating element is mounted and an inside module inside the glass disposed in registration with the outside module which contains an impedance matching circuit and in some instances, a ground plane, as necessary, for operation of the antenna. Consumers have welcomed the through-glass mounted antennas because it is no longer necessary to drill a hole through the vehicle which detracts from the vehicle's value. However, the blocking effect of the passenger compartment, coupled with through glass signal losses occurring with most glass mount antennas, provides an antenna having a lower gain and a higher pattern distortion than the roof-mounted antenna. Gain, for example, is normally in the 1-3 dB range. Most cellular telephone communications occur at operating frequencies of about 800 MHz. Even at these lower frequencies, improved coupling efficiency and lower distortion is desired.
Efforts at improving the performance of prior art glass mount mobile antennas have employed capacitive couplings through the vehicle glass and low-Q circuits involving LC impedance matching networks. For example, in U.S. Pat. No. 4,089,817 to Kirkendahl, a capacitively coupled antenna system is described. The capacitive coupling consists of electrical patches on both sides of the automobile glass, such as a windshield or window, which forms a capacitor to couple the RF energy. In U.S. Pat. No. 4,839,660 to Hadzoglou, an improved structure including a moderate coupling impedance wherein the bottom radiation element is close to a complete half-wave dipole is described. A full-dipole radiation element cannot be used because of the high transmission impedance sensitivity at one half wavelengths. Other illustrative examples of glass mount antennas employing different circuits to provide impedance matching networks for capacitive couplings include U.S. Pat. No. 4,992,800 to Parfitt; U.S. Pat. No. 4,857,939 to Shimazaki; and U.S. Pat. No. 4,785,305 to Shyu.
Each of these previous efforts to provide capacitive coupling by positioning electrical patches on both sides of the vehicle glass presents a number of attendant disadvantages. The electrically conductive patches generally may not be made large enough in comparison with the operating wavelength to keep it from being the primary radiating element. Accordingly, only high impedance couplings on the order of several hundred Ohms may only be provided which leads to high losses due to leakage of the electrical field at higher frequencies. At higher frequency bands like the proposed PCN/PCS band, even a small conductive patch is no longer effective to act as a lump capacitor element considering the thickness of the vehicle glass. A capacitance PI circuit bypasses the signal and makes it more difficult to match the high impedance of the antenna to a 50 Ohm system. In U.S. Pat. No. 4,764,773 to Larsen, an improved coupling structure is proposed, including two patches to reduce the coupling impedance. The Larsen antenna, however, still suffers from having the capacitor coupling limitation of requiring small patch sizes. At higher operating frequencies, this problem still exists or is exacerbated.
For mobile communications, it is critical to provide an antenna system having low pattern distortion. A whip collinear antenna does not always have a uniform current distribution. Frequently, a lower section has the strongest radiation. In a real-life automobile or other vehicle situation, the lower section of these antennas is actually blocked by the roof of the vehicle, causing severe pattern distortion and deep null. This situation is made worse at the higher proposed frequencies for PCN/PCS because the length of the radiators are only half that of the cellular band radiator, due to the doubling of the operating frequencies. A collinear array having a high feeding point, is normally provided by applying a de-coupling sleeve or by means of slot technology. These antennas normally have a 50-75 Ohm impedance which makes it difficult to adapt these antennas to the capacitively coupled prior art structures. As a result, outside impedance matching networks must be used to achieve a 50-50 Ohm transmission and even higher losses are expected at-the higher PCN/PCS frequency bands when these at conventional LC circuits are employed.
Another major shortcoming of prior art capacitively coupled antenna systems is that these kinds of systems suffer strong spurious emission to the passenger compartment simply because the whip collinear array needs a ground plane. Prior art methods used to isolate the feeding line from environmental radiation have relied on the couplers themselves to act as an impedance matching network. For example, in the above-mentioned Hadzoglou and Kirkendall patents, the coupling patches are part of the antenna's impedance matching network. In U.S. Reissue Patent 33,743 to Blaese, another capacitively coupled antenna system is described which attempts to couple the coaxial cable through the glass. At high frequency PCN/PCS bands the proposed 1/4 wave antenna would be only about 1.7 inches long, which would lie completely below the roofline of the vehicle causing severe pattern distortion and deep null. In U.S. Pat. No. 4,939,484 to Harada, a coupler including helix cavities is used to couple the signal through the glass. Unfortunately, the aperture is fixed to satisfy the 1/3 object frequency, as described in the Harada patent. For an 800 MHz cellular application, the helix should be designed for a 200 MHz frequency which has a Q factor of over 1,000 and enough coupling aperture. However, at a 1.8 GHz frequency band, the helix must be designed for 600 MHz. A 600 MHz helix cavity will have a small aperture of only about half that of the cellular band. A significant drop of unloaded Q is unavoidable, due to the thin helix and the coupling co-efficient is not sufficient to keep a 10% band width. Other drawbacks of the helix cavity approach described in the Harada patent are that in the proposed antennas, it is difficult to tune the frequency of the antenna system and it is difficult to manufacture the antennas because of its complicated structure.
Generally, the performance of the prior art antenna systems degrades considerably as frequencies approach the 1.5 GHz to 2.4 GHz range proposed for PCN/PCS communications. The prior art antennas and systems are relatively low frequency systems, when compared to microwave frequencies and they all employ low Q, lumped LC elements, or semi-lumped elements provided by placing the LC elements in metal enclosures. At the higher PCN/PCS frequencies, the losses of LC circuits will increase considerably due to the low, unloaded Q nature of the prior art systems and components. The PCN/PCS communication systems must operate at low power levels of about 1 Watt and provide a very wide range of coverage at very high frequencies. The prior art antenna systems are inappropriate for satisfying these requirements because of their low frequency approaches.
It is known in the filter arts that certain dielectric resonators may be used to build high-quality, narrow-banded filters, typically less than 2%. In filter applications, the dielectric resonators are normally placed in a continuously conductive enclosure to minimize any losses which may arise due to spurious modes or leakage. Illustrative dielectric resonators are described in U.S. Pat. No. 2,890,422 to Schlicke. The dielectric resonators have very good long-term stability so that component aging effects are negligible. The high density nature of the resonators reduces the undesirable effects of moisture to a minimum. Even at high frequency bands around 1.8 GHz, dielectric resonators may still maintain an unloaded Q factor of greater than about 3,000. In contradistinction, the helix cavities with a 600 MHz based frequency described in the Harada patent, cannot achieve such a high Q factor. The hollow-cavity helix systems described in the patent are more sensitive to the environment than dielectric resonators and special sealing is required to keep the Q from dropping further. Furthermore, it is impossible to keep sufficient coupling coefficient for a small helix aperture through a vehicle glass having a thickness from about 4 to about 6 mm, plus the thickness added by any adhesive mounting pads. The dielectric couplers solve the aperture problem of the Harada patent because the dielectric constant can be selected. For example, at 1.8 GHz, a dielectric resonator with a dielectric constant of 80 available commercially from Trans-Tech, Inc. under the trade designation 8600 Series has a dimension of D=24 mm, and h=7.6 mm. At 2.4 GHz, a dielectric resonator with constant of 38 also commercially available from Trans-Tech, Inc. under the designation Series 8800 may be used which has the dimensions D=24 mm and h=9.6 mm, which still provides a large enough aperture to maintain the coupling coefficient at a desirable level. On the other hand, an 800 MHz base frequency helix may have only a 10 mm aperture.
Accordingly, to overcome the shortcomings and disadvantages of the prior art systems and devices, it is an object of the present invention to provide a new and improved glass mount antenna system.
It is another object of the present invention to provide a glass-mount antenna system adapted to operate at upper UHF and higher microwave frequencies exhibiting greater coupling efficiency and less pattern distortion than has heretofore been achieved.
It is a further object of the present invention to provide a coupling scheme including a new and improved tuneable wide band coupling structure which provides flexible impedance matching to permit the feeding point of the antenna to be raised easily.
It is still another object of the invention to provide an antenna system having improved emission performance by employing twin enclosed cavities containing moisture-insensitive, high Q dielectric resonators and by implementing a feeding line isolating choke at the antenna end.
It is still a further object of the present invention to provide a glass-mount antenna system employing a resonance mode coupling, such as TE011 and TE111 modes, instead of electrical capacitance or inductance couplings.
It is still another object of the present invention to provide a high performance omni-directional PCN/PCS communication antenna system capable of coupling high frequency RF energy through a dielectric wall without the need for a continuously conductive enclosure and without significant losses.
SUMMARY OF THE INVENTION
In accordance with these and other objects, the present invention provides a new and improved antenna apparatus for mounting on the window of the vehicle which is adapted for operation in conjunction with a utilization device, such as a communication device, located within the vehicle. More particularly, the antenna apparatus comprises an exterior module and an interior module. The exterior module includes a first electrically conductive shroud member defining a first shielded cavity. The module additionally includes an elongated radiating element. A first low-loss, high Q dielectric resonator element adapted for resonant mode coupling is disposed in the first shielded cavity. Means are provided for electrically coupling the radiating element to the first dielectric resonator. Furthermore, means are provided for mounting the exterior module to an outside surface of the vehicle window so that the radiating element is disposed in an elevated feeding position.
The antenna apparatus additionally comprises an interior module which includes a second electrically conductive shroud member defining a second shielded cavity. A second low loss, high Q dielectric resonator element is disposed in the second shielded cavity and is adapted for resonant mode coupling with said first dielectric resonator. A coaxial feed line including an inner conductor and an outer conductive shield is provided for electrically coupling the interior module to said utilization device. The inner conductor of the feed line is electrically coupled to the second dielectric resonator. The outer conductive shield is electrically coupled to the second conductive shroud member. Means are provided for mounting the interior module to the inside surface of the vehicle window in general alignment with the exterior module so that the first dielectric resonator and the second dielectric resonator are disposed substantially in registration.
In accordance with the preferred embodiment of the invention, both the exterior module and the interior module are additionally provided with an electrically nonconductive dielectric outer housing adapted to surroundingly engage and protect the first and second electrically conductive shroud members. The preferred radiating elements will comprise semi-rigid coax-sleeve dipole type radiating elements. Semi-rigid coax-sleeve dipole antennas having at least one RF choke end portion are especially preferred. The dielectric resonators for use in the antenna apparatus for this invention may comprise dielectric resonators having a dielectric constant of at least about 80 and a Q factor of at least about 3000. Especially preferred dielectric resonators are cylindrical ceramic materials selected from Barium-Titanium-a Lanthanide Series element- (and optionally lead) oxide ceramics, such as, Ba-Ti-Pb-Nd oxide ceramic and Ba-Pb-Ti oxide ceramic materials. Ceramics of this type are commercially available from sources such as Trans-Tech, Inc. and Murata Erie North America Company. Additionally, for ultra-high frequency uses the ceramic may have a lower dielectric constant of about 38 and a Q factor of at least about 30,000. In accordance with the preferred embodiment, the inner or core conductor of the coax radiating element is electrically coupled to the first dielectric resonator and the outer radiator shield is electrically coupled to the first shroud member. In accordance with the preferred embodiment, the cylindrical ceramic dielectric resonators will have an aspect ratio, i.e. a length to diameter ratio (L/D) of less than about 0.4 to provide a satisfactory coupling coefficient. In especially preferred embodiments, large bandwidths are provided by employing metallic strip exciters disposed adjacent the ceramic resonators and between the resonators and the adjacent shroud walls.
In accordance with this invention, resonance mode coupling, such as TE011 and TE111 modes, instead of electrical capacitance or inductance coupling, provides a superior through glass antenna system for use at most frequencies and especially at high frequencies. More particularly, the vehicle glass is a dielectrical material which introduces considerable dielectric loss at high frequencies for electrical fields, but very low losses for concentrated TE011 and TE111 magnetic fields. TE011 and TE111 modes have very low loss and the E,H field distributions make them very suitable for the glass coupler applications. In accordance with this invention and utilizing this coupling method, high performance antenna systems for providing omni-directional communication with high radiation efficiency and low-pattern distortion are provided, especially at PCN/PCS frequencies of above about 1.5 GHz and preferably between about 1.5 GHz and 2.4 GHz.
Further objects and advantages of the invention will become apparent from the following Detailed Description of the Preferred Embodiment taken in conjunction with the Drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the new and improved resonant mode through glass antenna apparatus in accordance with the preferred embodiment of the invention shown in use in a mounted position on an automobile windshield;
FIG. 2 is an elevated cross-sectional view of the new and improved antenna apparatus of the invention shown in FIG. 1;
FIG. 3 is an exploded perspective view of the antenna apparatus in accordance with the preferred embodiment;
FIG. 4 is a perspective view with portions cut away to reveal the structure of the exterior module and the interior module of the new and improved antenna apparatus of the present invention shown in their respective assembled form;
FIG. 5 is a simplified electrical schematic diagram of the new and improved antenna of this invention;
FIG. 6 is an elevated cross-sectional view of an alternate antenna system in accordance with the present invention shown in use mounted to an automobile windshield;
FIG. 7 is an elevated side-view partly in section showing another alternate embodiment of the new and improved antenna system of this invention; and
FIG. 8 is a graphical plot illustrating the insertion loss and corresponding VSWR plots of a TE011 symmetrical mode glass coupler antenna apparatus in accordance with the preferred embodiments shown at increasing frequency values from 1.7 GHz to 1.9 GHz.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIGS. 1-4, a preferred embodiment of the new and improved antenna apparatus in accordance with this invention, generally referred to by reference numeral 10 is shown. As shown in the figures, the antenna apparatus 10 includes an exterior module assembly 14 and an interior module assembly 16 mounted on a vehicle window 12. The vehicle window 12 may comprise any dielectric window member within the vehicle and preferably will comprise a front or rear wind screen with the antenna apparatus 10 mounted adjacent an upper roof portion thereof.
Exterior module 14 includes an outer dielectric housing member 18 having a generally hollow cylindrical configuration with a closed end 20 and an opposed open end 22. A tubular angled radiator mounting sleeve 24 projects outwardly at an angle from the dielectric housing 18. The angle of the mounting sleeve 24 is preferably selected so that in its installed condition, the radiating element 26 is disposed in an elevated feed position, preferably above the vehicle roof.
As depicted in the preferred embodiments shown in FIGS. 1-4, a margin portion of the housing surrounding open end 22 is provided with a lip 28 having a latch-receiving recess 30 defined therein. The dielectric housing 18 may comprise any relatively non-conducting dielectric thermoplastic polymer. Preferably, the dielectrical housing comprises a shaped or molded polycarbonate member.
In accordance with the preferred embodiments depicted in FIGS. 1-4, the radiating element 26 will comprise a semi-rigid coax sleeve dipole radiator including an outer shield member 32 and an inner conductor 34. The coax dipole radiator element 26 includes an outwardly projecting free end 36 provided with an RF choke 38. The radiator 26 is preferably protectively covered in a dielectric sleeve 40 which may be made of any suitable thermoplastic polymer material, such as a thermoplastic polyester or a polyolefin. The protective sleeve 40 in accordance with the preferred embodiment is adapted for a slidable press-fit engagement onto the mounting sleeve 24 of dielectrical housing 18. The outer shield 32 and inner conductor 34 from radiator element 26 extend through an interior portion of mounting sleeve 24 to make an appropriate electrical coupling to other members of the exterior module 14, to be more particularly described hereinafter.
In accordance with this invention, the exterior module 14 additionally comprises a first electrically conductive shroud member 42 having a hollow open-ended cylindrical configuration including a closed end wall 44 and an opposed open end 46. A plurality of cap mounting notches or grooves 48 are provided in the sidewall of shroud member 42 adjacent open end 46. An aperture or feed hole 50 extends through a sidewall portion of shroud member 42 to permit the insulated inner conductor 34 from the radiator element 26 to pass therethrough. The outer shield conductor 32 of radiator element 26 is electrically coupled to the shroud member 42. Shroud member 42 defines a shielded recess or cavity 52 within the exterior module 14. Shroud member 42 should be configured to be closely telescopically received through the open end 22 of the dielectrical housing 18. Shroud member 42 may be made from any suitable electrically conductive material and, in accordance with the preferred embodiment depicted herein, the shroud member 42 is made of a brass alloy.
Exterior module 14 further includes a dielectric planar substrate 54 such as a printed circuit substrate having a cylindrical projecting mounting pin 56 extending from outwardly from one major surface 60 thereof. In accordance with the preferred embodiment, a loop-shaped conductive region 58 forming an exciter strip is provided on major surface 60 of planar substrate 54. The dielectric substrate 54 may comprise any suitable dielectrical material although low loss materials such as ULTEM® polyetherimide or other electrical grade thermoplastic polymer, such as polystyrene, may be used. The conductive exciter strip 58 may be in a looped configuration or a straight strip configuration and may be plated onto the planar substrate 54 or may comprise a separate metallic member affixed to major surface 60 of the substrate 54 by any suitable means such as, for example, by means of an adhesive. The planar substrate 54 in accordance with the preferred embodiment has a thin cylindrical or disc shaped configuration having a diametrical dimension selected to be closely telescopically received in the first shroud member 42 so that a second major surface 62 is disposed in abutting face-to-face relation with the closed end 44 of shroud member 42.
The thickness dimension of the planar substrate 54 is selected so that the exciter strip 58 is spaced a predetermined distance from the closed end 44 of the shroud member to define a desired impedance therebetween. The inner conductor 34 from the coax radiating element 26 is electrically coupled to the conductive metal strip 58 on the first major surface 60 of the planar substrate 54. Any suitable electrical coupling means may be used to achieve this result.
In accordance with the preferred embodiment, the exterior module 14 additionally comprises a dielectric resonator element 66 having a generally cylindrical configuration provided with a central core aperture 68 extending therethrough. Resonator element 66 is preferably a low-loss, high dielectric constant, high Q dielectric resonator made from ceramic materials having a dielectric constant of at least from about 75 to 100 and preferably at least about 80. Resonator element 66 may be slidably received on mounting pin 56 of the planar substrate 54 so that a major end wall surface 70 thereof is disposed adjacent to the conductive region 58 comprising the exciter strip defined on major surface 60 of planar substrate 54. Optionally, but preferably, a small amount of a suitable adhesive material may be disposed about the mounting pin 56 and core aperture 68 to maintain end surface 70 of resonator 66 in adjacent spaced relation to the exciter strip 58.
In accordance with the preferred embodiment depicted in FIGS. 1-4, exterior module 14 additionally comprises a thermoplastic cap member 72 having a thin disk-like cylindrical configuration. Cap member 72 includes a raised forwardly projecting lip 74 defining an adhesive-receiving recess region 75 on an outwardly facing major surface 77 thereof. Cap member 72 additionally includes a plurality of rearwardly projecting curved latch arms 76 each provided with free end portion 78 equipped with cooperating locking latches 80 intended to releasably engage the groove recess 30 provided in lip 28 on dielectric housing 18 to secure the exterior module 14 in a fully assembled condition. Cap member 72 includes a plurality of curving slots 82 defined radially inwardly from an edge portion thereof which are adapted to receive the raised edge portions defined between adjacent notches 48 in first shroud member 42. In the fully assembled condition as shown in FIGS. 2 and 4, the second major surface 84 of resonator 66 is positioned for flush mounting in face-to-face contact against the outside surface of vehicle window 12.
In accordance with the preferred embodiment depicted in FIGS. 1-4, a means for mounting the exterior module 14 to the vehicle window 12 preferably comprises an adhesive pad material 86 having adhesive bonding capabilities disposed on opposed surfaces thereof. A preferred adhesive pad 86 comprises an acrylic foam adhesive available from 3M Company.
In accordance with this invention, the new and improved antenna apparatus 10 additionally comprises an interior module 16 composed of component elements very similar to those comprising the exterior module 14. More particularly, and as best shown in FIGS. 1-4, the interior module 16 includes a second dielectrical housing 90 adapted to receive a second electrically conductive shroud member 92 to define a shielded cavity 94 within the interior module 16. A planar printed circuit substrate 96 provided with an electrically conductive region 98 thereon is provided which also includes a positioning pin 99 extending therefrom. A second dielectrical resonator 100 is provided within the shielded cavity 94 of the interior module 16 to provide resonance mode coupling in TE011 mode with the dielectric resonator 66 of the exterior module 14. Interior module 16 additionally includes a thermoplastic polymer cap member 102 provided with the releasable cooperative locking features to maintain the interior module 16 in fully assembled condition. An O-ring shaped adhesive pad 104 is also provided on an outer facing surface of the cap member to securely mount the interior module 16 against the inner surface of the vehicle window 12. The interior module 16 is adapted for electrical coupling to a coaxial feeder cable 106 including an inner insulated conductor 108 and an outer conductive shield 110. A crimp ferrule-type connector 112 extends outwardly from a sidewall of second shroud member 92 and through a groove or recess 114 provided in dielectrical housing 90. The conductive outer shield 110 of the coaxial feed cable 106 is electrically connected or coupled with the second shroud member 92 and the inner conductor 108 is electrically coupled to the conductive region 98 provided on planar substrate 96. The remote end of the coaxial feeder line 106 is in turn electrically coupled to the utilization device, such as a communication system, provided within the vehicle.
Referring now to FIG. 5, a schematic simplified diagram of the antenna system provided by the present invention is shown. The antenna system 10 of this invention relies upon more efficient RF coupling through resonance mode coupling of the two matched dielectric resonators such 66 and 100 to provide a high performance omni-directional communication antenna.
In accordance with this invention, the exterior module 14 and interior module 16 are mounted on opposed surfaces of vehicle window 12 in general alignment with each other so that the dielectrical resonators 66 and 100 are disposed substantially in registration with each other.
The new and improved microwave dielectric resonators 66 and 100 used in the antenna apparatus 10 of this invention have very low loss and high Q values in comparison with the LC lumped circuits and distributed transmission line systems of the prior art. In glass-coupled antenna contexts, it is an important feature to minimize the surface current on the sidewall of the metal closures defined by first and second shroud members 42 and 92, respectively. This is important because there is no overall common enclosure in a glass mount, through window antenna situation. Accordingly, the dielectric constant of the resonators must be sufficiently high and the electromagnetic field distribution must be appropriately considered in selecting the appropriate resonance mode.
In accordance with this invention, it is an important structural aspect to attempt wherever possible to avoid cutting surface current. For this reason, high dielectric constants for the dielectric resonators 66 and 100 are required and ceramic resonators are especially preferred. For this specification application, Barium and Titanium based oxide ceramics including at least one Lanthanide Series component and optionally a lead component such as Ba-Pb-Nd-Ti Oxide ceramic or Ba-Pb-Ti Oxide ceramic materials are preferred because of their high dielectric constant values of 80 to 90. They also have high Q factors and the unloaded Q versus frequency for these materials can be approximately expressed as being from about 4500 to about 9000/f(GHz). For higher frequencies of operation, e.g., at or about 2.4 GHz, a Zr-Sn-Ti ceramic material may be used which has a lower dielectrical constant on the order of between about 20 to about 45 and preferably of about 38 but a Q factor having a much higher value of 40,000 per/f (GHz). Traditionally, aspect ratios (L/D ratios) for the dielectric resonators of L/D=0.4 were frequently used to insure that the nearest spurious mode was avoided. In the design context for the antenna apparatus of this invention, the glass wall effect should be considered in designing to suppress spurious modes and when using dielectrical resonator materials having a dielectrical constant of 80, an L/D ratio of less than 0.4 is generally suitable for almost all kinds of passenger vehicle glass.
In accordance with the preferred embodiments, the exciter strips 58 and 98 are employed in combination with the dielectric resonators to provide a wider bandwidth coupling. Preferably, the exciter strips 58 and 98 are selected to have an electrical length of less than about 0.25 waveguide wavelength and especially preferably will have an electrical length of about 0.22 waveguide wavelength. The impedance formed between the exciter strip 58 or 98 and the shroud end wall, such as 44 of the shroud member 42, may be selected to be from about 50 to 100 Ohms as required for any various antenna type.
Referring now to FIG. 6, an alternate antenna apparatus 128 is shown. Antenna apparatus 128 includes a radiator or antenna member 130 selected from any kind of sleeve dipole or elongated collinear array type having at least one RF choke 131 disposed at an end portion thereof to isolate the feeding line emissions and to lift the feeding point above roof level on the vehicle. A soft, thin cable assembly 142 having an outside conductor connected to a conductive shroud and having an inner conductor soldered to the exciter strip comprises the outside feed line. The end of the cable is connected to the antenna member 130. Housings 120 and 141 have essentially the same structure. Dielectric resonator exciter assemblies are constructed in the shielded cavity formed by the cylindrical conductive shroud housings 121 and 145 with dielectric resonator members 122 and 144 mounted inside by a support 143 and a coupler body 120, respectively. The strip exciters 124 and 146 on the sidewalls of the resonators 122 and 144 are metal strip lines made by conventional printed circuit printing techniques or are metal strips attached to the resonator members 122 and 144. A cable 150 is the feeding line connected to the PCN/PCS transceiver. A tuning plate 123 in accordance with this embodiment, may be provided to trim the frequency of the overall apparatus 128. Alternatively, the distance between the resonators may be changed because the resonator pairs have a smooth tuning chart when spurious modes are successfully suppressed. A tunable antenna system of the type depicted in the antenna apparatus 128 may be more useful when the thicknesses of the glass window structures vary a great deal. Generally, however, a tuning plate moveable toward and away from the exciter strip 124 by rotation of a threaded screw member is optional and not generally necessary.
In accordance with this invention, the dielectric resonators may have a generally square configuration and be adapted for TE111 mode coupling. TE111 couplers may also be employed wherein the exciter strip is disposed on a side edge surface of the resonating element. By way of illustration only and not limitation, the square ceramic dielectric resonators may have dimensions of about 23 mm×23 mm×7.1 mm to provide resonators having a dielectrical constant of about 80 and useful at a 1.8 GHz band.
Referring now to FIG. 7, the above described techniques are not limited to 50 to 50 Ohm couplings. By modifying the width of the strip exciter members, the antenna apparatus and coupling assembly may also work with regular whip collinear array radiators having a lower section length of nearly 1/2 wavelength or 5/8 wavelength. In the prior art, collinear arrays with a 5/8 wavelength lower section could not directly be used because the capacitively coupled design required that the load had to be inductive. As depicted in FIG. 7, an economical arrangement for a typical 3 dB collinear whip is shown. The collinear whip antenna is formed by elements 235 through 238 where 237 can either be 1/2 or 5/8 of wavelength in length. The element 238 is a swivel foot connected to the microstrip line member 272 which forms a 1/4 wavelength loop exciter strip on substrate 270 which is adjacent to resonator element 244. Element 271 is the ground plane on the other side of the microstrip line. The impedance of the microstrip line can be from 50 to 75 Ohms and then tapered to the required antenna base impedance. The internal module coupling box 220 may generally be the same as those described above.
Referring now to FIG. 8, a typical coupler used for PCN band in accordance with the present invention adapted for operating at frequencies ranging from about 1.7 GHz to 1.9 GHz shows that for the new and improved antenna apparatus 10 of this invention less than a 1 dB loss through a 6 mm thick windshield glass occurred over a bandwidth of 11% at 1.8 GHz. The curve shown in FIG. 8 indicate that the spurious response is kept away from the useful bandwidth. If a smaller bandwidth is preferred, the insertion losses can be made even smaller due to the high Q nature of the dielectric resonators.
Although the present invention has been described with reference to certain preferred embodiments, modifications and changes may be made therein by those skilled in this art without departing from the scope and spirit of the present invention as defined by the appended claims. | An improved glass mount antenna system employs a pair of high dielectric constant, high Q, low loss dielectric resonators for TE011 and TE111 resonance mode coupling to couple RF energy through the glass to thereby provide an omni-directional communication antenna system characterized by high radiation efficiency and low pattern distortion. The antenna assemblies are especially well suited for high frequency communication operations, for example at microwave bands of between about 1.5 GHz to 2.4 GHz, currently contemplated for PCN/PCS communications. | 7 |
FIELD OF INVENTION
This invention concerns a gas-generating composition useful for inflating air bags for protection of occupants of motor vehicles. More particularly, this invention is directed to a gas-generating composition wherein no water or toxic substances are formed during the gas-generating reaction and wherein the solid components resulting from the reaction are in the form of a glassy slag.
BACKGROUND OF INVENTION
Air bags for protection of motor vehicle occupants must be inflated by the gas-generating composition within a fraction of a second, and they are generally constructed so that their gas content is released at a controlled rate. The propellant formed for such air bags must not contain any toxic components.
Alkali and alkaline earth metal azides in particular, which form nonpoisonous gas consisting essentially of nitrogen when reacted with an inorganic oxidizing agent, come into consideration as the gas supplying component of such compositions. Alkali and alkaline earth metal oxides, which form during oxidation, are relatively difficult to separate and may reach the interior of the vehicle. To make the oxide harmless, it is known, for example, from German Auslegeschrift 2,236,175, that silicon dioxide may be added to the gas-generating composition. The silicon dioxide and the alkali and alkaline earth metal oxides form a glassy slag, the separation of which presents no problems.
The composition disclosed by German Auslegeschrift 2,236,175, as used in practice, contains 56% sodium azide on a weight basis, a relatively high proportion. Moreover, sodium azide is highly toxic, comparable in this respect to potassium cyanide. Due to the constant increase in the number of motor vehicles which are equipped with such protection equipment, the disposal problems which arise when scrapping are appreciable. These problems result both from direct contamination of the environment, particularly soil and subterranean water with this highly toxic salt, and from the reaction of sodium azide on the scrap heap with acids. For example, sodium azide can come into contact with bacterial acids to form highly explosive heavy metal azides.
Therefore, every effort is made to reduce the azide content of such compositions or to make do without azides. For example, azide-free compositions based on solid rocket fuels have been disclosed in German Auslegeschriften 2,334,063 and 2,222,506. However, these compositions have a serious disadvantage; carbon monoxide and other toxic gases are formed from the carbon containing components thereof.
To avoid carbon monoxide formation, the use of oxygen-free oxidizers, such as chromium chloride, molybdenum disulfide or iron fluoride and tetrazoles as a nitrogen source has been disclosed in European Pat. No. 0,055,904. In these reactions, a propellant is formed which contains free metal, i.e. chromium, molybdenum or iron, and in some cases, substances which are even substantially more toxic, such as potassium cyanide. Furthermore, in view of the long time span over which an air bag must be usable, for example, more than ten years, the chemical stability of this composition leaves much to be desired.
Azide-free gas-generating compositions based on nitrides or an amine have been disclosed by German Offenlegungsschrift 2,407,659; these compositions generate gas by reacting according to the following equations: ##STR1##
The nitrides used, namely sodium nitride in reaction (1), magnesium nitride in reaction (3), calcium nitride in reaction (4) and sodium amide in reaction (2) are exceptionally reactive compounds. In fact, these compounds react especially vigorously with water, forming ammonia. Since the complete absence of water is practically unattainable with such a finely dispersed system, the stability of these known compositions is inadequate. At the same time, the decomposition of these known compositions with water leads to malodorous, toxic ammonia.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a new azide-free gas-generating composition of high stability capable of forming an adequately large volume of nitrogen per unit volume of composition.
Another object of the invention is to provide a new azide-free gas-generating composition with high stability which, while forming an adequately large volume of nitrogen per unit volume of composition, leads to a physiologically safe propellant gas.
These and other objects are accomplished by the invention described below.
A gas-generating composition based on a nitride and an oxidizing agent has been discovered which fulfills the objects of the invention, according to which, the nitride is selected from at least member of the group consisting of boron nitride (BN), aluminum nitride (AlN), silicon nitride (Si 3 N 4 ) and a transition metal nitride or a mixture thereof.
DETAILED DESCRIPTION OF INVENTION
The nitrides used in accordance with the invention are exceptionally stable, thermally and chemically, to an extent that they are also used as ceramic materials. It is surprising, therefore, that these inert materials can be caused to react under the conditions of temperature and pressure existing in an air bag generator housing with conventional oxidizing agents for gas-generating compositions, i.e. ammonium, alkali and alkaline earth metal nitrates and perchlorates.
The nitride used in the gas-generating composition of the invention is selected exclusively from boron nitride (BN), aluminum nitride (AlN), silicon nitride (Si 3 N 4 ) and a transition metal nitride or a mixture thereof. As the transition metal nitride, preferably titanium nitride (TiN), zirconium nitride (ZrN), hafnium nitride (HfN), vanadium nitride (VN). niobium nitride (NbN), tantalum nitride (TaN), chromium nitride (CrN), dichromium nitride (Cr 2 N) or a mixture of these nitrides is used.
When either chromium nitride or a mixture of boron nitride and chromium nitride is used as the nitride and potassium nitrate is the oxidizing agent, the reaction of these compositions of the invention proceed according to the following equations:
10CrN+6KNO.sub.3 →3K.sub.2 O.5Cr.sub.2 O.sub.3 +8N.sub.2 +2626 kj/mole (5)
3BN+2CrN+3KBO.sub.3 →3KNO.sub.2.Cr.sub.2 O.sub.3 +4N.sub.2 +1168 KJ/mole (6)
As shown in equations (5) and (6), as a result of the gas-generating reaction of a composition of the invention, the total solid residue is bound in the form of 3K 2 O.5Cr 2 O 3 or 3KBO 2 .Cr 2 O 3 , i.e., as a glassy slag. Moreover, nitrogen is formed exclusively as the propellant gas.
With respect to the nitrides, it is important to note that although the proportion of nitrogen on a weight basis is appreciably less in the nitrides used in the composition of the invention than in conventionally used sodium azide, the proportion on a volume basis is comparable. For example, the proportion of nitrogen by weight in sodium azide is 64.6%; by volume it is 1.2 normal liters/cc. For CrN, the proportion by weight is only 21.2%; however, the proportion by volume is 1.02 normal liters/cc.
It follows from the foregoing, for example, that the mixture illustrated in equation (5) forms only 0.14 normal liters of nitrogen per gram, as compared with about 0.31 normal liters of nitrogen per gram which are generated by the known composition disclosed by German Auslegeschrift 2,236,175, which contains sodium azide. However, the volume of gas formed by the reaction of equation (5) is 0.58 normal liters/cc. compared with 0.65 normal liters/cc. for the known composition. In other words, per unit volume of composition, the formation of nitrogen by a composition of the invention is approximately comparable to that of a conventional gas-generating composition containing sodium azide.
To ensure that the nitride bonds with the alkali metal, the nitride and oxidizing agent are used in stoichiometric ratios, as illustrated in equations (5) and (6). Further, to achieve defined reactive or oxidative properties, it may be advantageous to employ mixtures of nitrides used in accordance with the invention.
Any inorganic oxidizing agent may be used as the oxidizing agent in the compositions of the invention. However, for practical reasons, potassium nitrate is preferred, since, despite a relatively low decomposition temperature, it is comparatively stable, has a low hygroscopicity and moreover, is readily available.
If necessary, an ignition aid based on a metal powder/oxidizing agent mixture may be added to the composition of the invention. As the metal powder, use may be made of boron, magnesium, aluminum, zirconium, titanium or silicon, for example. Examples of useful inorganic oxidizing agents include ammonium, alkali and alkaline earth metal nitrates and perchlorates.
The following example further illustrates the invention, but must not be considered to limit the invention in any manner.
EXAMPLE
A mixture of finely ground chromium nitride (CrN), potassium nitrate, and boron was prepared. The potassium nitrate was present in a stoichiometric amount such that it was adequate to oxidize the chromium nitride and boron completely. The mixture was compressed into tablets with a diameter of 6 mm. and a thickness of 2.5 mm. About 80 g. of the tablets were introduced into a conventional gas generator housing for an air bag, as described in German Patent No. 2,915,202 and ignited by means of an electrical igniter and a booster charge based on boron and potassium nitrate. The metal nitride is oxidized with release of the theoretical amount of nitrogen. | A nitrogen-generating composition useful for inflating air bags to protection for occupants of motor vehicles is disclosed which is composed of a stable nitride resistant to high temperatures and an inorganic oxidizing agent. | 2 |
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
[0001] This patent application claims the benefit of U.S. Provisional Patent Application No. 60/555,517, filed Mar. 23, 2004.
FIELD OF THE INVENTION
[0002] This invention pertains to motorcycle handlebars, and more particularly, to motorcycle handlebars with the electrical wiring disposed within the handlebars.
BACKGROUND OF THE INVENTION
[0003] Many biker enthusiasts upgrade various components of their motorcycle. One such component is the handlebar. The handgrip areas of a handlebar are almost universally used for mounting controls including electrical switches for operating lights, horns and directional signals. The manual operating controls such as throttles and brakes usually have external cables. However, the electrical switches, which usually are small gauged wires that are relatively fragile, often have their insulated wires protected by running through the interior of the handlebar tube from the handgrip regions and exit the handlebar somewhere near the tree.
[0004] Typically, the handlebars are formed from a single tube of tubular steel and bent in a suitable shape to provide the mounting location for the handgrips. The central section of the handlebar is secured to the top tree of the motorcycle with fasteners or via risers. The risers and associated clamps can loosen during operation, which results in the handlebar rotating if it is not properly secured. A better method to produce and install handlebars is needed.
[0005] The invention provides such a method to produce and install handlebars. These and other advantages of the invention, as well as additional inventive features, will be apparent from the description of the invention provided herein.
BRIEF SUMMARY OF THE INVENTION
[0006] The invention provides a handlebar assembly that provides the ability to economically produce handlebars. The handlebar is formed from multiple pieces. The pieces include a mounting piece that connects to two handlebar pieces that are bent to form the handlebar shape and mounts to the top tree. The mounting piece is sized to fit a particular style of tree. The pieces are permanently joined by means such as welding, bonding, brazing, etc.
[0007] The handlebar pieces are rotated to a desired horizontal angle and a desired vertical angle prior to being joined to the mounting piece. The handlebar pieces may be rotated or otherwise formed to a wide range of angles and configurations based upon the desired position of the rider. The mounting piece may be solid or be hollowed out with support members. The solid mounting piece has an internal channel for passing wire to and through the handlebar pieces.
[0008] Other aspects and features, and advantages of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is an isometric view showing the handlebar of the invention installed on a motorcycle;
[0010] FIG. 2 is an isometric view of the pieces of handlebar of FIG. 1 ;
[0011] FIG. 3 is a side view of the handgrip area of the handlebar of FIG. 1 ;
[0012] FIG. 4 a is a bottom view of an embodiment of the mounting piece in accordance with the teachings of the invention;
[0013] FIG. 4 b is a bottom view of an alternate embodiment of the mounting piece;
[0014] FIG. 4 c is an end view of the mounting piece of FIG. 4 a along line 4 c;
[0015] FIGS. 4 d - 4 h illustrate various tops of the mounting piece and is a cross-sectional view of the mounting piece of FIG. 4 a along line 4 d - h;
[0016] FIG. 5 is an isometric view of the handlebar of the invention installed on a top tree of a motorcycle;
[0017] FIG. 6 is an isometric view of the handlebar of FIG. 5 illustrating electrical wires running through the handlebar assembly;
[0018] FIGS. 7-8 illustrate various embodiments of the handlebar assembly of the invention;
[0019] FIG. 9 illustrates an alternate embodiment of the handlebar in accordance with the invention;
[0020] FIG. 10 a illustrates an embodiment of the handlebar having a mount for a tachometer and/or other instrumentation; and
[0021] FIG. 10 b is a cross sectional view of the handlebar of FIG. 10 a illustrating the pre-drilled slot section.
[0022] While the invention will be described in connection with certain preferred embodiments, there is no intent to limit it to those embodiments. On the contrary, the intent is to cover all alternatives, modifications and equivalents as included within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF THE INVENTION
[0023] The invention provides a method to build handlebars that allows standard parts to be put together to produce numerous styles of handlebars. The method eliminates the need for risers and clamps and streamlines and simplifies the installation process by having a single unit to install. In one embodiment, the handlebars when installed create the illusion that the fork tubes continue through the tree and become the actual handlebar. Turning to the drawings, wherein like reference numerals refer to like elements, the invention is illustrated as being implemented in a suitable motorcycle. Those skilled in the art will appreciate that the invention may be practiced with other motorcycle configurations.
[0024] FIG. 1 illustrates an example of a suitable motorcycle 20 on which the invention may be implemented. The handlebar 22 mounts on the tree 24 of the motorcycle 20 . In one embodiment, the handlebars create the illusion that the fork tubes continue through the tree and become the actual handlebar. This embodiment is illustrated in FIG. 1 . The handlebar 22 has a mounting piece 26 that is mounted to the tree 24 and handlebar sections 28 . Equipment and accessories (generally designated by 30 ), such as grips 32 , clutch lever 34 , brake lever 36 , mirror 38 and switches 40 , are attached to the handlebar sections 28 and grip tubes (as shown in FIG. 2 ).
[0025] FIG. 2 shows the handle bar sections. The handlebar 22 has a mounting piece 26 , handlebar tube 50 , grip tube 52 , and bushing 54 . The grip tube 52 is inserted into opening 56 of bushing 54 and is attached to handlebar tube 50 . The tube 52 and bushing 54 may be welded, brazed, bonded, etc. to handlebar tube 50 . The material of tubes 50 , 52 , and bushing 54 is metal, aluminum, or other durable material. The bushing 54 has opening 58 (see FIG. 3 ) for enabling electrical wire to be run through the tube 50 to connect to electrical components such as a throttle, horn, turn signal, and the like. Note that the size and location of opening 58 will vary, depending on model and manufacturer.
[0026] The handlebar section 28 , which consists of handlebar tube 50 , grip tube 52 , and bushing 54 , is attached by welding, brazing, bonding, etc. to mounting piece 26 at a desired horizontal and vertical angle. For example, the handlebar section 28 can be such that section 60 is straight up with respect to mounting piece 26 (i.e., angle θ=0 and angle δ=0 where θ is the angle from the vertical axis “z” towards the “xy” plane and δ is the angle from the horizontal axis “x” towards the “yz” plane) or at any other angles.
[0027] Turning now to FIG. 4 a, the mounting piece 26 has threaded holes 70 for mounting the mounting piece 26 to tree 24 from the bottom so that the top 72 of the mounting piece is continuous (see FIG. 4 c ). The mounting piece 26 is sized based on the tree being used. In one embodiment, the mounting piece is forged, machined, stamped, or extruded barstock and is chrome plated after assembly. A logo may be placed on the mounting piece 26 . A channel 74 for routing electrical wire 62 (see FIG. 2 ) is provided along one side of the mounting piece 26 . While FIGS. 4 a - h show the channel 74 along one side, those skilled in the art will recognize that the channel may be placed on the opposite side shown. The mounting piece 26 has an opening 76 that fits over the opening on the tree 24 for passing wire (see FIG. 6 ). The mounting piece may be a solid piece as shown in FIG. 4 a or it may have a solid section 78 as shown in FIG. 4 b that results in less material being used in mounting piece 26 . Solid section 78 may be welded or bonded to mounting piece 26 or it may be part of the mounting piece when the mounting piece is forged, machines, or stamped. The top 72 of the mounting piece 26 may comprise various radii. FIGS. 4 d - 4 h illustrate various radii 72 1 to 72 5 . Note that any other desirable profile or contour can be used.
[0028] FIG. 5 illustrates the handlebar 22 mounted to a tree 24 . The standard stock fork tube plug nut (not shown) on the tree is covered by handlebar section 28 . A replacement plug or a modified plug is used if the stock plug interferes with the handlebar installation. FIG. 6 illustrates electrical wires 62 1 , 62 2 routed through the opening 76 , channel 74 and handlebar tube 50 . FIGS. 7 and 8 illustrate various styles of handlebar tubes 50 1 to 50 29 attached to mounting piece 26 . The mounting piece is selected based on the style of handlebar tubes and the style of bike (e.g., motorcycle type).
[0029] Turning now to FIG. 9 , an alternate embodiment of the handlebar of the invention is shown. The handlebar has mounting piece 26 , handlebar tube 50 , grip tube 52 , and riser 80 . The riser is welded, brazed, or otherwise attached to mounting piece 26 . In this embodiment, only one handlebar tube 50 is required. The handlebar tube 50 is attached to riser 80 .
[0030] Turning now to FIG. 10 a, the mounting piece 26 may also have a slot 90 pre-drilled through a portion of the mounting piece 26 (see FIG. 10 b ) such that a consumer can finish drilling out the slot to mount instrumentation 92 (e.g., a tachometer) to the mounting piece. A mounting bracket 94 that has a mounting through-hole for the tachometer wiring and tachometer (or multiple through-holes) and a threaded hole (not shown) for mounting the bracket 94 to the mounting piece 26 is used. The instrumentation wiring is fed through the through-hole and tree to the appropriate location in the motorcycle.
[0031] The handlebar is manufactured by receiving customer parameters and manufacturing the handlebar to meet the customer parameters. The customer parameters include a desired handlebar style, a desired handlebar horizontal angle, a desired handlebar vertical angle, and a bike type. The desired handlebar style includes the various styles of handlebar tubes illustrated in FIGS. 7 and 8 as well as custom styles. The bike type indicates the type of motorcycle (e.g., Harley Davidson cruiser) from which the tree configuration and size can be determined. The mounting piece is selected from the bike type. The handlebar tubes are selected based on the desired handlebar style and are bent to the desired configuration (e.g., horizontal and vertical angles). The grip tube and bushing is connected to the handlebar tubes. The handlebar tube is mounted to the mounting piece and integrally attached therewith as previously described.
[0032] The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) is to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.
[0033] Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context. | A handlebar assembly that provides the ability to economically produce handlebars is presented. The handlebar is formed from multiple pieces. The pieces include a mounting piece that connects to two handlebar pieces that are bent to form the handlebar shape and mounts to the top tree. The mounting piece is sized to fit a particular style of tree. The pieces are permanently joined by means such as welding, bonding, brazing, etc. The handlebar pieces are rotated to a desired horizontal angle and a desired vertical angle selected by the consumer prior to being joined to the mounting piece. The mounting piece may be solid or be hollowed out with a central support member. The solid mounting piece has an internal channel for passing wire to and through the handlebar pieces. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention is generally directed to stands for use with hunting and target archery bows and more particularly to a bi-pod stand having a pair of detachable legs which include vibration damping elements to thereby reduce vibrational energy transmitted to the legs during use of the bows.
2. Brief Description of Related Art
A variety of stands have been developed for purposes of supporting archery bows not only to facilitate storage or display but also to provide stabilizing structures when bows are used for target use or hunting. In U.S. Pat. No. 3,256,872 to Koser, a stand and stabilizer for long bow type archery bows is disclosed which includes a bracket which is mountable to a portion of the riser or body of the bow and from which extend a pair of legs which form a bi-pod support structure. The legs are threadingly engaged with a block which is pivotally mounted to the bracket allowing the positioning of the legs. The stand is specifically designed for a long bow requiring that the bracket be attached to the body of the bow. When not in use, the legs are designed to be positioned adjacent to the body of the bow by pivoting the legs relative to the support bracket.
Stands have also been specifically designed for use with compound archery bows which generally include a stabilizer receiver or hole along the riser portions of the bows. U.S. Pat. No. 5,106,044 to Regard et al. discloses a portable compound bow stand having a bracket which is designed to be threadingly secured to the stabilizer receiver in the riser and which also includes a pair of legs forming a bi-pod stand. The legs are pivotal relative to the bracket to allow them to be positioned either at a forward support position or retracted against the lower portion of the bow when not in use.
A variation of support stand for compound type archery bows is disclosed in U.S. Pat. No. 4,360,179 to Roberts. The bow stand includes a single primary support leg which is treadingly received with the stabilizer receiver mounted or provided along the riser portion of the bow and a supporting bracket mounted at the bottom of the bow serving as a stabilizing surface.
At least a portion of each of the foregoing stands is specifically designed to remain fixed to the bow when not in use. Other examples of bow stands are disclosed in U.S. Pat. Nos. 6,205,992, 5,547,162 4,993,398, Des 314,303 and Des 406,302.
SUMMARY OF THE INVENTION
The present invention is directed to a stand for archery bows and particularly compound archery bows which have a stabilizer receiver or hole for selectively receiving a stabilizer device wherein the stand includes a bracket which is securable relative to the stabilizer receiver. The bracket includes a pair of spaced guide sleeves of a size to slidingly receive a pair of leg members therein such that the leg members are removable with respect to the guide sleeves. Securing means are provided in association with the guide sleeves to retain the leg members in position with respect to the bracket.
Each of the leg members includes a vibration damping member formed of a material which dampens vibrations along the length of the legs when the bow is fired. The stand functions as a bi-pod in cooperation with a lower cam or wheel of the compound bow to provide a stable support for the bow to maintain the bow in a vertical position. The legs may be easily removed and stored when not in use.
In preferred embodiments, the legs are formed of a carbon fiber material which may be solid or hollow in cross section. In some embodiments the vibration damping members are frictionally engaged about the legs whereas, in other embodiments, the vibration damping members are formed as plugs placed with the legs.
It is a primary object of this invention to provide a bow stand for use with different types of archery bows which can be easily mounted to a bow and wherein the legs may be removed from a mounting bracket associated with the bow stand.
It is yet a further object of the present invention to provide for vibration damping of the legs of a bow stand by providing vibration damping elements along each of the legs of a bi-pod stand such that vibrational energy directed along the legs is damped when a bow is fired.
BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the invention will be had with respect to the accompanying drawings wherein:
FIG. 1 is a front perspective illustrational view of the bow stand of the present invention mounted to a compound archery bow;
FIG. 2 is a front elevational view of the bow stand of FIG. 1 ;
FIG. 3 is a left side view of the bow stand of FIG. 2 ;
FIG. 4 is a partial rear elevational view of the bow stand of FIG. 2 ; and
FIG. 5 is a partial cross sectional view taken along line 5 — 5 of FIG. 1 ;
FIG. 6 is a partial rear elevational view of a varied embodiment of bow stand wherein the legs are hollow in cross section;
FIG. 7 is a cross sectional view taken along line 7 — 7 of FIG. 6 ;
FIG. 8 , is a partial cross sectional view taken through one of the legs of another embodiment of the invention showing an internal vibration damping plug; and
FIG. 9 is a partial view of one of the legs of a further embodiment of the invention showing the vibration damping member in a form of an external sleeve.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With continued reference to the drawings, a bow stand 10 is shown as being secured to a riser 14 of a compound bow 12 . Although the stand is shown as being particularly adapted for use with a compound bow having a conventional stabilizer mount 15 to which a stabilizer member 16 is selectively secured, the stand may be used with other bows having means for securing a stabilizer or other add-on devices associated therewith for purposes of securing the stand including recurve bows and long bows.
The compound bow shown in the drawing includes upper and lower mounting plates 17 and 18 which are used to secure upper and lower flexible limbs 19 and 20 , respectively, to the upper and lower ends 21 and 22 , respectively, of the bow riser 14 . The limbs are secured using hand manipulatable threaded fasteners 23 and 24 .
A bow string section 28 is operatively connected to a cable system 30 which extends about an upper pulley or cam wheel 32 and lower pulley or cam wheel 34 . In compound bows, the cable system is used with upper and lower wheels or upper and lower cams. A cable guide 35 extends rearwardly of the bow riser 14 .
The bow riser includes a hand grip 38 positioned below an arrow support notch or shelf 39 . Vibration dampers 40 and 41 may be provided along the upper and lower flexible limbs as is shown in FIG. 1 .
Most compound bows are provided with a threaded receiver along a lower portion of the riser for selectively permitting the mounting of a stabilizer. As previously noted, the bow shown includes a modified stabilizer mount 15 which extends forwardly of the riser and includes a threaded receiver 45 for receiving a threaded end 46 of the stabilizer 16 . The stand 10 of the invention is specifically designed to be quickly and easily assembled and mounted to the bow 12 using the stabilizer 16 as a securing element, however, a separated securing element or fastener could be used. The stand includes an upper bracket 50 having an opening 51 for receiving the threaded end 46 of the stabilizer therethrough so that, as the stabilizer is secured to the stabilizer mount 15 , the bracket is secured therebetween.
A pair of spaced guide sleeves 52 and 53 are provided on opposite sides of the bracket 50 . The sleeves are open at their lower end and are of a size to cooperatively slidingly receive upper ends of legs 55 and 56 . Adjustable locking bolts or set screws 58 and 59 are threadingly received within openings in the guide sleeves to thereby lock the legs in adjusted and assembled position relative to the bracket 50 . When not in use, the legs may be quickly detached and stored in the archers quiver or other device to permit easy transport through wooded terrain or while traveling.
The legs 55 and 56 are preferably formed of carbon fiber or vibration damping materials, and, when assembled, form a bi-pod structure which functions with the lower cam 34 as a third leg for stability. The legs are designed to reduce vibration and, in a first embodiment, are provided with vibration dampers 60 and 61 which are formed of any suitable elastomeric material such as a rubber or synthetic rubber material. The dampers include central openings therethrough of a size which is complementary to the configuration of the legs such that the dampers extend around and are frictionally slidably mounted to the legs to thereby reduce undesirable vibrations which are generated along the legs when the bow is in use. The leg dampers provide an added benefit to the archer or hunter when using the bow 12 . The lower end of each leg may include plastic or other type of cap 64 .
The dampers 60 and 61 may vary in size, material and configuration. In this respect, in FIG. 9 , the dampers are shown as elastomeric sleeves 65 which are frictionally engaged such as shown on leg 56 to thereby provide for vibration damping.
The specific reference to FIGS. 6–8 , a varied embodiment of the invention is disclosed in greater detail. In this embodiment, the stand includes the same bracket 50 including spaced guide sleeves 52 and 53 for mounting a pair of legs. In this embodiment, however, the legs 70 and 71 are formed as hollow tubes. The legs are removably mounted with respect to the sleeves 52 and 53 and are secured utilizing set screws 58 and 59 as previously described.
In the present embodiment, due to the hollow nature of each of the legs, a reinforcing metallic pin or plug 72 is mounted in the upper end of each of the legs and is adhesively secured within the upper portion of the tube. In this manner, set screws will not crush the upper hollow portion of the legs when tightened to secure the legs to the bracket 50 .
In the present embodiment, dampers such as disclosed at 60 and 61 in the previous embodiment may be used or dampers such as shown at 65 in FIG. 9 may be used. As an alternative, however, a damping plug 75 , as shown in FIG. 8 , may be inserted within each of the hollow legs in order to provide the necessary vibration damping. The same type of elastomeric material utilized with respect to the other embodiments of the invention may be used to form the plugs which are seated within either the upper or lower portion of the hollow legs. As with the previous embodiments, the damping members may be placed at substantially any place along the length of each of the legs depending upon the size and configuration of the damping members and the desired damping effect to be obtained.
With the present invention, the bracket may be left in mounted relationship between the stabilizer and the riser section of the bow with the legs being removed and stored for easy portability. With this arrangement, the bracket does not interfere with the normal use of the bow with the legs removed and therefore provides an additional benefit over conventional bow stands.
The foregoing description of the preferred embodiment of the invention has been presented to illustrate the principles of the invention and not to limit the invention to the particular embodiment illustrated. It is intended that the scope of the invention be defined by all of the embodiments encompassed within the following claims and their equivalents. | An adjustable and collapsible stand for archery bows which includes a pair of vertically adjustable legs carried by a bracket which is mounted to a bow and wherein vibration damping elements are mounted to each leg to thereby reduce vibrational energy created during use of the bow. | 5 |
[0001] The present application claims the benefit of the filing date of U.S. Provisional Application Ser. No. 60/974,115 (filed Sep. 21, 2007), incorporated by reference herein.
FIELD OF THE INVENTION
[0002] This invention relates to DNA isolation from a biological sample and more particularly to the isolation of DNA from whole blood having been fixed and preserved.
BACKGROUND OF THE INVENTION
[0003] The isolation of DNA is a necessary step in many diagnostic testing procedures. In general, DNA isolation uses a series of extraction and washing steps which often result in DNA shearing and the failure to remove unwanted materials from the DNA sample. A contaminated DNA sample makes it difficult if not impossible to use the sample as a diagnostic tool. A number of patent documents address such processes for the isolation of DNA and RNA. See, generally, U.S. Pat. Nos. 7,173,124; 6,914,137; 6,548,256; 5,945,515; and 5,898,071 all incorporated by reference herein. Notwithstanding the above, there remains a need for DNA isolation methods that can be performed in an efficient and inexpensive manner while maintaining the integrity of the DNA and eliminating the shearing and contaminants often associated with traditional methods of isolation.
[0004] The most common method for isolating nucleic acids involves lysing the sample containing the DNA, extracting the mixture with an organic solvent and precipitating the DNA through the addition of alcohol. This method is time consuming and involves the use of hazardous materials in that it commonly requires the use of phenol or other toxic organic solvents.
[0005] To avoid the use of hazardous materials, another method involves lysing the sample containing the DNA with a chaotropic substance such as urea or guanidinium chloride and combining the sample with a DNA binding solid phase. The DNA binds to the solid phase and any remaining unwanted components or impurities are washed away. While less time consuming, this process results in unwanted contaminants and often removal of sections of the DNA, or DNA shearing.
[0006] Further methods include mixing an initial sample with a detergent substance which acts to separate unwanted lipids and proteins from the DNA. The unwanted contaminants are removed and the DNA is extracted using a salt. While again avoiding the use of toxic chemicals, this method usually results in undesired DNA shearing and contaminants.
[0007] A blood or tissue sample fixed with certain fixatives is disclosed in U.S. Pat. Nos. 5,196,182; 5,260,048; 5,459,073; 5,460,797; 5,811,099; and 5,849,517, each incorporated herein by reference. A blood or tissue sample may also be collected and fixed in a specific type of tube, such as that disclosed in U.S. application Ser. No. 10/605,669, incorporated herein by reference.
[0008] The present invention addresses the need for an efficient and consistent method of DNA extraction by providing an improved method for the isolation of nucleic acids from a biological sample including the initial step of fixing the biological sample in order to maintain the structural integrity and purity of the isolated DNA.
SUMMARY OF THE INVENTION
[0009] In a first aspect, the present invention contemplates a method for isolating DNA comprising: providing a tube containing an anticoagulant agent and a fixative agent; suspending a sample in the fixative agent; contacting the sample with an erythrocyte lysis buffer; contacting the sample with a nucleus lysis buffer; contacting the sample with proteinase K; and contacting the sample with ethanol.
[0010] This aspect may be further characterized by one or any combination of the following features: the fixative agent is selected from the group consisting of diazolidinyl urea, imidazolidinyl urea, dimethoylol-5,5dimethylhydantoin, dimethylol urea, 2-bromo-2.-nitropropane-1,3-diol, oxazolidines, sodium hydroxymethyl glycinate, 5-hydroxymethoxymethyl-1-1aza-3,7-dioxabicyclo [3.3.0]octane, 5-hydroxymethyl-1-1aza-3,7dioxabicyclo [3.3.0]octane, 5-hydroxypoly[methyleneoxy]methyl-1-1aza-3,7dioxabicyclo [3.3.0]octane, quaternary adamantine and combinations thereof, the erythrocyte lysis buffer includes ammonium chloride, ammonium bicarbonate, and a chelating agent, wherein the chelating agent is EDTA, the nucleus lysis buffer includes ingredients selected from the group consisting of a chelating agent, a buffer, an anionic surfactant, a polysorbate surfactant, a non-ionic surfactant, and a chaotrope, the nucleus lysis buffer includes a buffer, a chelating agent and an anionic surfactant and the buffer is tris-HCL.
[0011] In another aspect, the present invention contemplates a method for isolating DNA comprising: providing a tube containing an anticoagulant agent and a fixative agent selected from the group consisting of diazolidinyl urea, imidazolidinyl urea, and combinations thereof; suspending a sample in the fixative agent; contacting the sample with ammonium chloride, ammonium bicarbonate, and EDTA; contacting the sample with a nucleus lysis buffer wherein the nucleus lysis buffer contains a buffer, a chelating agent and an anionic surfactant; contacting the sample with proteinase K; and contacting the sample with ethanol.
[0012] This aspect may be further characterized by one or any combination of the following features: the buffer is tris-HCl, the chelating agent is EDTA and the anionic surfactant is sodium dodecyl sulfate, the fixed sample is transferred to a remote location prior to a cell lysis processing step and the isolated DNA is analyzed and resulting data is provided to an initial sample draw location, the remote location, an additional location, or any combination thereof.
[0013] In a further aspect, the present invention contemplates a method of DNA isolation and analysis comprising: providing a tube containing an anticoagulant agent and a fixative agent selected from the group consisting of diazolidinyl urea, imidazolidinyl urea, and combinations thereof; extracting a sample from a patient at a sample extraction site; suspending the sample in the fixative agent; transporting the fixed sample to a remote location; contacting the sample with ammonium chloride, ammonium bicarbonate, and EDTA; contacting the sample with a nucleus lysis buffer wherein the nucleus lysis buffer contains a buffer, a chelating agent and an anionic surfactant; contacting the sample with proteinase K; contacting the sample with ethanol; analyzing any resulting isolated DNA; providing data regarding the resulting isolated DNA to the sample extraction site, the remote location, an additional site, or any combination thereof.
[0014] In a further aspect, the present invention contemplates a method for isolating DNA comprising: providing a tube containing an anticoagulant agent and a fixative agent; suspending a sample in the fixative agent; contacting the sample with an erythrocyte lysis buffer; contacting the sample with a nucleus lysis buffer; contacting the sample with proteinase K; and contacting the sample with ethanol.
[0015] This aspect may be further characterized by one or any combination of the following features: the fixative agent is selected from the group consisting of diazolidinyl urea, imidazolidinyl urea, dimethoylol-5,5dimethylhydantoin, dimethylol urea, 2-bromo-2.-nitropropane-1,3-diol, oxazolidines, sodium hydroxymethyl glycinate, 5-hydroxymethoxymethyl-1-1aza-3,7-dioxabicyclo [3.3.0]octane, 5-hydroxymethyl-1-1aza-3,7dioxabicyclo [3.3.0]octane, 5-hydroxypoly[methyleneoxy]methyl-1-1aza-3,7dioxabicyclo [3.3.0]octane, quaternary adamantine and combinations thereof, the fixative agent is diazolidinyl urea, the fixative agent is imidazolidinyl urea, the erythrocyte lysis buffer includes ammonium chloride, ammonium bicarbonate, and a chelating agent, the chelating agent is EDTA, the nucleus lysis buffer includes ingredients selected from the group consisting of a chelating agent, a buffer, an anionic surfactant, a polysorbate surfactant, a non-ionic surfactant, and a chaotrope, the nucleus lysis buffer includes a buffer, a chelating agent, a polysorbate surfactant, a non-ionic surfactant and a chaotrope, the nucleus lysis buffer includes a buffer, a chelating agent and an anionic surfactant, the chelating agent is EDTA, the buffer is tris-HCL, the chelating agent is EDTA and the anionic surfactant is sodium dodecyl sulfate, one or more samples are extracted from one or more patients at a sample extraction site, the sample suspended in the fixative agent is transferred to a remote location prior to a cell lysis processing step or isolated DNA is analyzed and resulting data is provided to the sample extraction site, the remote location, an additional location, or any combination thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a flow diagram illustrating an example protocol for a DNA isolation method.
[0017] FIG. 2 is a flow diagram illustrating an example protocol for a DNA isolation method.
DETAILED DESCRIPTION
[0018] In general, the invention herein contemplates a method of improved DNA isolation which includes initial fixing of a blood or tissue sample, proper storage of the sample in an appropriate device, and processing the blood or tissue sample through a number of lysing and protein removal steps to arrive at isolated DNA.
[0019] The present invention provides a method for the isolation of nucleic acids. The nucleic acid may be DNA or RNA or any combination thereof. In one preferred embodiment, nucleic acid is nuclear DNA or mitochondrial DNA. The samples from which the nucleic acids may be isolated include any biological sample including whole blood. The method disclosed herein allows for the efficient isolation of DNA and RNA samples with little to no shearing and few contaminants through the initial fixing of a tissue or blood sample.
[0020] The process for improved DNA isolation begins by contacting a blood or tissue sample with a fixative to maintain the integrity of the components within the sample, primarily the integrity of those components containing DNA. Fixatives that may be used include, but are not limited to, diazolidinyl urea, imidazolidinyl urea, dimethoylol-5,5dimethylhydantoin, dimethylol urea, 2-bromo-2.-nitropropane-1,3-diol, oxazolidines, sodium hydroxymethyl glycinate, 5-hydroxymethoxymethyl-1-1aza-3,7-dioxabicyclo [3.3.0]octane, 5-hydroxymethyl-1-1aza-3,7dioxabicyclo [3.3.0]octane, 5-hydroxypoly[methyleneoxy]methyl-1-1aza-3,7dioxabi cyclo [3.3.0]octane, quaternary adamantine and combinations thereof.
[0021] The initial fixing of the tissue or blood sample has the effect of preserving the nucleic acids within the cells. The fixing step will also provide a sample with a longer shelf life. In a preferred embodiment, the fixative solutions comprise an active agent in solution. Suitable solvents include water, saline, dimethylsulfoxide, alcohol and mixtures thereof. Preferably, the fixative solution comprises diazolidinyl urea (Du) and/or imidazolidinyl urea (IDU) in a buffered salt solution. In a highly preferred embodiment, the fixative solution further comprises polyethylene glycol and EDTA.
[0022] The preferred solvent depends upon the tissue or cells being fixed. For example, where large pieces of tissue are being fixed, it is preferable to use an alcohol solvent since the alcohol solvents increase penetration. Preferably, the alcohol solvents comprise one or more alkanols and/or polyols.
[0023] The amount of an active agent used to fix a tissue or blood sample is generally about 10 to about 200 grams per liter. In a preferred embodiment the fixative solutions comprise about 4 to about 6 grams of IDU per 100 ml of buffered salt solution and/or about 1 to about 20 grams of Du per 100 ml of buffered salt solution.
[0024] In a preferred embodiment, the initial fixing step can occur within a specialized device, wherein the fixative agent is already present in the device prior to addition of the tissue or blood sample. More preferably, the device is an evacuated collection container, usually a tube. The tube is preferably made of a transparent material that will also resist adherence of the cells within a given sample. Most preferably, the tube further includes an anticoagulant agent and a fixative agent including but not limited to those disclosed above. The tube may also optionally include polyarcylic acid or another suitable acid. Preferably, the compounds included in the tube are in an amount sufficient to preserve the cells' morphology and nucleic acids without significant dilution of the cells. In another preferred embodiment, blood is fixed simultaneously as it is drawn into the specialized tube. The tube may also be coated with a protective coating.
[0025] In one preferred embodiment, the step of fixing allows the blood or tissue sample to be stored for a period of time prior to the DNA isolation process. More preferably, a blood or tissue sample may be drawn at one location and fixed and later transported to a different remote location for the DNA isolation process. In one preferred embodiment, the results from the DNA isolation process are analyzed at the remote location and the resulting diagnostic information is reported to the site of the original blood draw. In another preferred embodiment, the results from the DNA isolation process may be sent from the remote location and analyzed at a third location or alternatively the results may be sent back to the site of the initial blood draw and analyzed there. The resulting diagnostic information may then be sent to a third location or back to the remote location or the site of the initial blood draw.
[0026] In one preferred embodiment, the fixing step allows for the DNA isolation process to take place about 3 days after fixing. In another preferred embodiment, the DNA isolation process may take place about 24 hours after fixing. Preferably, the DNA isolation process may take place about 12 hours after fixing. More preferably, DNA isolation process may take place about 6 hours after fixing
[0027] At any time after the initial fixing of the tissue or blood sample, the sample can be treated to isolate the nucleic acids located within the sample cells. Preferably, if the DNA is being extracted from blood cells, it is first necessary to break the cell membranes or lyse the blood cells in order to access the nucleic acids within the cell nuclei or mitochondria. Post-lysing and throughout the isolation process it is important to constantly remove all unwanted materials and/or contaminants from the sample. Preferably, this is done by centrifuging the sample for any where from 2 minutes to 20 minutes and discarding the supernatant. Preferably, the lysing step followed by centrifuging is repeated a number of times in an effort to remove as many contaminants as possible.
[0028] One preferred embodiment of the present invention is a method for isolating DNA from whole blood. The method can be performed on a single sample or on a multitude of samples in a multi-well plate. The method includes fixing the starting material as previously discussed, then mixing the fixed sample with a lysing substance to break the red blood cells. The sample is then centrifuged and the supernatant is discarded. The lysing and centrifuging steps are repeated until a visual inspection indicates that contaminants have been minimized. An appropriate concentration of salt and alcohol is added to precipitate DNA containing material. Proteinase K or a similar enzyme is then added to release DNA from cross-linked proteins in the DNA containing material. An organic compound such as a phenol derivative or the like is then added to remove any remaining protein contaminants. Any protein contaminants that still remain can be removed by adding additional amounts of an organic compound such as a phenol derivative or the like. After centrifugation, ethanol is added and the sample is centrifuged again. Any remaining liquid is removed from the sample and only the DNA will remain. In one preferred embodiment, the finished product of isolated DNA is contacted with a buffer.
[0029] In a preferred embodiment, the cell lysis step is performed by a buffer, preferably an erythrocyte lysis buffer which may contain NH 4 Cl, NH 3 HCO 3 , EDTA, sodium dodecyl sulfate, NaOH, sodium citrate, sodium acetate, citric acid, HCl, cacodylic acid sodium salt, sodium dihydrogen phosphate, disodium hydrogen phosphate, imidazole, triethenolamine hydrochloride, tris-HCl, or combinations thereof.
[0030] The cell lysis step may also be performed by a nucleus lysis buffer which may contain tris-HCl, EDTA, SDS, NH 4 Cl, NH 3 HCO 3 , sodium dodecyl sulfate, NaOH, LiCl, sodium citrate, sodium acetate, citric acid, HCl, cacodylic acid sodium salt, sodium dihydrogen phosphate, disodium hydrogen phosphate, imidazole, triethenolamine hydrochloride, polysorbate, octyl phenol ethoxylate, or combinations thereof.
[0031] Incubation may occur on ice or at any temperature between −30° C. and 70° C. Preferably, a sample should be incubated at about −20° C. after all lysis steps have been completed. In one preferred embodiment, a sample is incubated in a water bath at about 50-65° C. after addition of a proteinase K. Preferably, centrifugation occurs at speeds of about 500 to about 15,000 rpm. More preferably, centrifugation occurs at about 1,000 to 13,000 rpm. In one preferred embodiment, centrifugation is performed at about 1-20° C. More preferably, centrifugation is performed at about 4-9° C.
[0032] It will be appreciated from the teachings herein including the teachings of U.S. Provisional Application Ser. No. 60/974,115, filed Sep. 21, 2007 (see e.g. Appendices I & II, incorporated by reference) that the following are illustrations of how the present invention may be practiced.
EXAMPLE 1
[0033] Mix 1 ml of whole blood with 5 ml of erythrocyte lysis buffer in a 15 ml centrifuge tube. Vortex briefly and incubate for 10 to 20 minutes on ice to lyse the red blood cells. Centrifuge at 1000 rpm for 10 minutes at 4-9° C. and discard the supernatant. Add 2 ml of erythrocyte lysis buffer to cell pellet. Re-suspend the cells by vortexing briefly at high speed. Centrifuge at 1000 rpm for 10 minutes at 4-9° C. and discard supernatant. It is important to remove the supernatant as much as possible to avoid incomplete lysis of white blood cells. If desired, the process can be stopped at this point and the cell pellet can be maintained at −80° C. for many months. To proceed, prepare a white blood cell lysis buffer by adding β-mercaptoethanol to nucleus lysis buffer in a 1:100 dilution ratio. Mix well by inverting. Add the white blood cell lysis buffer to the cell pellet and vortex until no cell clumps are visible. Transfer the cell lysate to a clean microcentrifuge tube. Add 1/10 volume ( 1/10 of cell lysate) of 5M NaCl to the cell lysate and mix well by inverting. Add 1 volume (equal volume of cell lysate) of 100% isopropanol to the cell lysate and mix well by inverting. Incubate at −20° C. for a minimum of 20 minutes. Again, the process can be stopped at this point as the DNA is considered stable. To proceed, centrifuge at 4° C. and 13,000 rpm for 20-30 minutes. Pour off the supernatant and discard. Add 1 ml 70% ethanol to the pellet, vortex for 1 to 10 seconds and centrifuge at 4° C. and 13,000 rpm for 10 minutes. Pour off the supernatant and discard. Repeat the addition of ethanol and centrifuging. Drain the microcentrifuge tube and allow DNA pellet to air dry in the open tube. Add 200 μl TE buffer to the tube. Add proteinase K (100 μg/ml) to the DNA solution, mix gently, and incubate at 56° C. for about 0.5 to 12 hours.
EXAMPLE 2
[0034] Repeat all steps of Example 1. Continue by adding an equal volume of phenol:chloroform:isoamyl alcohol (25:24:1 saturated with 10 mM Tris, pH 8.0 or 1 mM EDTA) to DNA solution. Vortex for 10 seconds and centrifuge at 12,000 rpm at room temperature for 5 minutes. Take the aqueous phase containing the DNA and transfer to a new tube. Add 1/10 volume ( 1/10 of cell lysate) of 5M NaCl to the cell lysate and mix well by inverting. Add 1 volume (equal volume of cell lysate) of 100% isopropanol to the cell lysate and mix well by inverting. Incubate at −20° C. for a minimum of 30 minutes. Again, the process can be stopped at this point as the DNA is considered stable. To proceed, centrifuge at 4° C. and 13,000 rpm for 20-30 minutes. Pour off the supernatant and discard. Add 1 ml 70% ethanol to the pellet, vortex for 10 seconds and centrifuge at 4° C. and 13,000 rpm for 10 minutes. Pour off the supernatant and discard. Repeat the addition of ethanol and centrifuging. Drain the microcentrifuge tube and allow DNA pellet to air dry in the open tube. Add 200 μl TE buffer to the tube.
EXAMPLE 3
[0035] Repeat all steps of Example 1. Add 67 μl of protein precipitation solution to DNA solution. Vortex to mix and incubate on ice for 5 minutes. Centrifuge at 13,000 rpm at room temperature for 10 minutes. Remove the supernatant to a clean microcentrifuge tube. Add 1/10 volume ( 1/10 of cell lysate) of 5M NaCl to the cell lysate and mix well by inverting. Add 1 volume (equal volume of cell lysate) of 100% isopropanol to the cell lysate and mix well by inverting. Incubate at −20° C. for a minimum of 30 minutes. Again, the process can be stopped at this point as the DNA is considered stable. To proceed, centrifuge at 4° C. and 13,000 rpm for 20-30 minutes. Pour off the supernatant and discard. Add 1 ml 70% ethanol to the pellet, vortex for 10 seconds and centrifuge at 4° C. and 13,000 rpm for 10 minutes. Pour off the supernatant and discard. Repeat the addition of ethanol and centrifuging. Drain the microcentrifuge tube and allow DNA pellet to air dry in the open tube. Add 200 μl TE buffer to the tube.
EXAMPLE 4
[0036] Mix 1 volume of whole blood with 5 volumes of erythrocyte lysis buffer in a centrifuge tube. Vortex briefly and incubate for 10 to 20 minutes on ice to lyse the red blood cells. Centrifuge at 1000 rpm for 10 minutes at 4-9° C. and discard the supernatant. Add 2 volumes of erythrocyte lysis buffer to the cell pellet, re-suspend the cells by vortexing at high speed. Centrifuge at 1000 rpm for 10 minutes at 4-9° C. and discard supernatant. Prepare white blood cell lysis buffer by adding β-mercaptoethanol to nucleus lysis buffer in a 1:100 dilution ratio and proteinase K (100 g/μl). Add white blood cell lysis buffer to the cell pellet, vortex and incubate cell lysate mixture at 50-65° C. for 15 minutes to overnight. Cool the lysate to room temperature for 2 minutes and add 1/10 volume (equal volume of cell lysate) of 5M NaCl to the cell lysate and mix well by inverting. Add 1 volume (equal volume of cell lysate) of 100% isopropanol to the cell lysate and mix well by inverting. Incubate at −20° C. for a minimum of 30 minutes. Again, the process can be stopped at this point as the DNA is considered stable. To proceed, centrifuge at 4° C. and 13,000 rpm for 20-30 minutes. Pour off and discard the supernatant. Add 1 ml 70% ethanol to the pellet and vortex for 1 second. Centrifuge at 4° C. and 13,000 rpm for 10 minutes. Pour off and discard the supernatant. Add another 1 ml 70% ethanol to the pellet and vortex for 1 second. Centrifuge at 4° C. and 13,000 rpm for 10 minutes. Pour off and discard the supernatant. Drain the tube and allow the DNA pellet to air dry in an open tube. Add 200 μl TE buffer to the tube.
[0037] It will be appreciated that concentrates or dilutions of the amounts recited herein may be employed. In general, the relative proportions of the ingredients recited will remain the same. Thus, by way of example, if the teachings call for 30 parts by weight of a Component A, and 10 parts by weight of a Component B, the skilled artisan will recognize that such teachings also constitute a teaching of the use of Component A and Component B in a relative ratio of 3:1.
[0038] It will be appreciated that the above is by way of illustration only. Other ingredients may be employed in any of the compositions disclosed herein, as desired, to achieve the desired resulting characteristics. Examples of other ingredients that may be employed include antibiotics, anesthetics, antihistamines, preservatives, surfactants, antioxidants, unconjugated bile acids, mold inhibitors, nucleic acids, pH adjusters, osmolarity adjusters, or any combination thereof.
[0039] The explanations and illustrations presented herein are intended to acquaint others skilled in the art with the invention, its principles, and its practical application. Those skilled in the art may adapt and apply the invention in its numerous forms, as may be best suited to the requirements of a particular use. Accordingly, the specific embodiments of the present invention as set forth are not intended as being exhaustive or limiting of the invention. The scope of the invention should, therefore, be determined not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are incorporated by reference for all purposes. Other combinations are also possible as will be gleaned from the following claims, which are also hereby incorporated by reference into this written description. | A method for isolating nucleic acids is disclosed, wherein a sample having nucleic acid containing starting material is fixed, lysed, and treated to remove unwanted contaminants. The initial fixing of the sample aids in maintaining the structure and integrity of the isolated DNA and reduces the incidence of end product contaminants and DNA shearing. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to a novel drainage quilt for use in a subterranean drainage system. More specifically, this invention relates to a filtered drainage quilt which may be used for removing water from soil around subterranean walls, for distributing water into leach, drainage or irrigation fields, and for a number of other uses where it is necessary to relieve or redirect water and other fluid flow.
When constructing a house or a building with subterranean walls, it is necessary to install a system which facilitates drainage of water away from the subterranean walls. Water must not sit near the foundation of the structure because, over time, the water can degrade the integrity of some waterproofing membranes or damproofing and leak into interior spaces. Most foundations are made of cinder block or poured or precast concrete, and waterproofed with various bituminous or rubber waterproofing membranes or bituminous damproofing materials. The presence of hydrostatic pressure encourages leakage of water through any void or weakness in the membrane or dampproofing, through sub-grade walls and floors to the interior of habitable spaces rendering them nonusable.
Different sources of water which could contribute to the presence of hydrostatic pressure include ground, surface, and roof and gutter water. Ground water must be taken into account when designing below grade spaces. It can be at different elevations at different times of the year. Surface water, generally the largest amount of water that needs to be controlled, comes from rain, melting snow, and drainage from other areas of the building site. Surface water may be diverted away from a house by building the structure on a high point. Additionally, the land surrounding the building is sloped downward in order to direct water away from the building. However, some amount of surface water seeps into the ground, and if not dealt with, will cause or add to hydrostatic pressure buildup.
Roof and gutter water may be routed away from the house in two ways: dispersed on the surface away from the building or piped away underground. Surface dispersal is attractive because it is easy to monitor; most problems that may occur are noticeable and correctable. Surface dispersal is also less expensive than piping. However, even when this method is effective, the water remains near the foundation. As a complement to surface dispersal, the underground system channels the water away from the foundation through a network of subterranean pipes.
The function of a drainage system is to remove water from the soil surrounding a building, while concurrently filtering or preventing movement of soil particles. In the past, removal of ground water and relief from hydrostatic pressure have been accomplished by underground drainage systems which include porous or perforated pipes, such as PVC, and gravel or crushed rock. In these drainage systems, gravel or crushed rock is placed over and around the pipe to relieve hydrostatic pressure and to direct the ground water to the perforated pipe. A filter fabric is placed on top of the gravel to prevent soil from mixing with the gravel and clogging paths to the perforated pipe. Backfill is then placed on top of the filter fabric and in the area next to the subterranean wall.
The filter fabric mentioned above is usually referred to in the art as a geotextile and is typically made up of non-woven fibers, such as polypropylene. The fibers are melted and extruded into continuous filaments, and are then formed into layered sheets and punched with barbed needles that entangles the filaments into a strong bond.
Problems have arisen in connection with the above described conventional drainage system. First, gravel or crushed rock is not readily available in all locals and may be expensive to transport to job sites. Additionally, gravel and crushed rock are heavy and somewhat burdensome and expensive to install at a job site. Finally, the geotextile fabric can be dislodged when placing backfill over the fabric, allowing possible mixing of the dirt and gravel. Dirt may then enter and clog the perforated pipes, thereby rendering the drainage system nonfunctional and providing no relief from hydrostatic pressure to the subgrade walls. Clogging remains a problem even when the system is carefully designed with the particle size distribution of filter media and aggregate media properly matching the native soil in the region to be drained.
Most current drainage systems utilizing geotextile wraps over gravel cores still require careful design and labor intensive installation procedures.
Subterranean drainage quilts are prefabricated and offer many advantages over the gravel/covering systems, including ease of installation and reduction of cost. A number of prior art prefabricated systems have been developed which utilize vertical fins comprising open plastic core surrounded by polymer filter fabric to intercept and channel the underground water into drainage pipes.
Such systems offer substantially more reliable drainage systems, but these systems are hampered by the need for careful installation and labour intensive on-site assembly of the drainage fins and the tubing into continuous lengths. The drainage tube necessarily incorporated into the system is an additional cost component, because the filter cloth covered fins themselves do not provide enough built-in flow capacity, when subjected to lateral soil pressure to conduct water away from the site quickly, without the provisions of the additional pipe or conduit.
Hence, the use of such systems has been restricted to specialized drainage situations where higher on-site installed costs can be tolerated.
A septic tank system receives all waste fluid from a house or small building and delivers the waste fluid to a septic tank. The septic tank then breaks down the waste fluid to liquified sewage and other wastewater by utilizing either anaerobic or aerobic bacteria. The liquified sewage is then piped from the septic tank via drain lines to a leaching field, where the liquid is dispersed into an absorption field.
The pipes which carry the liquid from the septic tank to the leaching field are perforated or porous, such as PVC, and are conventionally surrounded by a mineral aggregate, such as gravel.
The subterranean drainage systems, as described above, may be used in connection with a septic system; however, the aforementioned problems associated with present subterranean drainage systems remain.
The difficulties suggested in the preceding are not intended to be exhaustive but rather are among many which may tend to reduce the effectiveness of prior drainage systems. Other noteworthy problems may also exist; however, those presented above should be sufficient to demonstrate that drainage systems appearing in the past will admit to worthwhile improvement.
OBJECTS and BRIEF SUMMARY OF THE INVENTION
Objects
It is therefore a general object of the invention to provide a novel drainage quilt for use in conjunction with a subterranean drainage system which will obviate or minimize difficulties of the type previously described.
It is a specific object of the invention to provide a drainage quilt which will reduce hydrostatic pressure when positioned adjacent a subterranean wall.
It is another object of the invention to provide a drainage quilt which will prevent soil from entering porous or apertured fluid handling conduits used in conjunction with conventional subterranean drainage systems.
It is still another object of the invention to provide a drainage quilt which is flexible and may therefore be used in conjunction with varying shaped pipes.
It is a further object of the invention to provide a drainage quilt which is lightweight and therefore easy to transport and install.
It is yet a further object of the invention to provide a drainage quilt which will withstand sufficient compression loading from backfill to meet the drainage requirements of the site.
It is still a further object of the invention to provide a drainage quilt which will not degrade in situ and is biocompatible with chemicals in the soil.
It is yet another object of the invention to provide a drainage quilt which is inexpensive to produce, easily manufactured and recycles in a unique manner materials that would otherwise be disposed of in land fills or create disposal problems such as old rubber tires and certain plastics.
BRIEF SUMMARY OF A PREFERRED EMBODIMENT OF THE INVENTION
A preferred embodiment of the invention which is intended to accomplish at least some of the foregoing objects comprises a drainage quilt which operably rests adjacent to a subterranean conduit and facilitates water removal and dispersal from underground drainage sites. The drainage quilt includes a water permeable membrane configured in a generally rectangular container and a plurality of drainage members disposed within the container. The water permeable membrane is composed of a filter fabric and operably restricts earth fines from transversing the membrane. The container includes generally rectangular first and second surfaces, which oppose each other, and four side surfaces perpendicularly connected to the first and second surfaces to achieve the rectangular shape.
The drainage members are composed of cubes of expanded polystyrene, chunks of old rubber tires or other non ground polluting material and are positioned in a homogeneous fashion to create drainage paths through the subject quilt. These elements serve to increase the relative area of drainage delivered to a subterranean pipe. The drainage members may be fabricated in varying sizes to increase void space between adjacent members or for ease of handling.
Flexible positioning ties extend perpendicularly through the first and second surfaces of the drainage quilt and serve to retain the relative positioning of the drainage members. The ties prevent the drainage members from assembling at any one area of the drainage quilt and thus encourage an equal distribution of fluid flow throughout the quilt. This effect could also be achieved by stitching the filter fabric in the shape of adjacent tubes.
THE DRAWINGS
Other objects and advantages of the present invention will become apparent from the following detailed description of a preferred embodiment thereof taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is an axonometric view disclosing a context of the subject invention and depicts a subterranean building wall and a drainage quilt of the instant invention positioned between a drainage pipe and the surrounding earth;
FIG. 2 is a detailed axonometric view of a drainage quilt in accordance with the subject invention;
FIG. 3 is a detailed cross-sectional view of the subject drainage quilt, as taken along line 3--3 in FIG. 2;
FIG. 4 is a partial broken-away plan view disclosing another context of the invention and depicts the subject drainage quilt as utilized in a septic system.
DETAILED DESCRIPTION
Context of the Invention
Before discussing in detail a preferred embodiment of the subject drainage quilt, it may be useful to briefly outline an operative environment of the invention. Referring now to the drawings, wherein like numerals indicate like parts, and initially to FIG. 1, there will be seen an operative context of the subject invention. In this connection, FIG. 1 shows a detailed axonometric view of a subterranean wall 10, which may be composed of cinder block, poured or precast concrete, or the like. Such subterranean walls typically comprise foundations for residential and commercial buildings and rest upon a footer 12. An interior floor 14, typically composed of concrete, extends within the subterranean wall 10. Soil or porous backfill material 16 surrounds the wall 10 and is generally moisture laden. The exterior side of the wall 10 is waterproofed, to a degree, by a coating 18 composed of bituminous or sheet membrane waterproofing material.
In order to reduce hydrostatic pressure buildup on the exterior surface of the wall 10, a perforated or porous drainage pipe 20 rests on the footer 12 to collect ground water and drain the water to a peripheral location.
As a substitute for a crushed rock or gravel bed currently used in the construction industry, a drainage quilt or mat 22 of the instant invention is shown in an operative posture adjacent to the drainage pipe 20 and beneath the backfill 16. The drainage quilt 22 facilitates the passage of ground water from the backfill 16 to the drainage pipe 20, which drains the water away from the building foundation. In this context, the drainage quilt reduces the hydrostatic pressure adjacent the wall 10 and alleviates the problems described above in connection with conventional construction practice. The detailed structure and advantages of this novel drainage quilt will be discussed in detail below.
Drainage Quilt
Turning now to FIG. 2, shown is a detailed broken-away axonometric view of the subject drainage quilt 22. The drainage quilt 22 includes a first surface 24, a second surface 26 (not shown), and four side surfaces 28. In a preferred embodiment, the surfaces of the drainage quilt 22 are sewn together with thread or wire or alternatively stapled together to form a generally rectangular container. The standard dimension of the drainage quilt is approximately 10'×3'×1', though any dimension is possible depending on the requirements of the drainage system to be built.
The first 24 and second 26 surfaces and side surfaces 28 of the drainage mat 22 are composed of a flexible, water permeable membrane which restricts earth fines from entering the quilt 22. The membrane may be composed of one of any of the approximately two hundred available geotextile filter fabrics currently available in the market.
The drainage quilt 22 is filled with drainage members 30 composed of expanded or extruded polystyrene. The drainage members 30 fill the drainage quilt 22 in a generally homogeneous fashion so that sufficient void spacing is provided to permit the flow of water or other fluids through the quilt 22. While a cubical configuration for the drainage members is preferred, other three dimensional configurations are contemplated by the subject invention such as solid rectangles or other polyhedron configurations and the like as desired. In addition, materials other than polystyrene may be used in practicing the invention, such as polyisocyanurate, polyurethane, phenolic and the like. The drainage members may be fabricated with other materials, such as various recycled plastics, consistent with the requirements that chunks of used rubber tires, and the like, the material does not deteriorate when buried, is compatible with chemicals in the soil, is nonpolluting, and can withstand compression pressure from the backfill. Moreover, the size of the drainage members may be varied with different drainage quilts, or further within an individual drainage quilt, depending upon the desired drainage capabilities. However, it has been determined that optimum drainage results are achieved when the drainage quilt is fashioned with members having a cubic volume ranging from 0.125 to 3.375 inches cubed, with an average-sized cube having a 1"×1"×1" dimension.
Referring particularly to FIG. 3, there will be seen a cross-section of the subject drainage quilt 22 as taken along line 3--3 in FIG. 2. Positioning ties 32 extend from the first surface 24 of the drainage quilt 22 through the drainage members 30 to the second surface 26 and serve to retain relative positioning of the drainage members 30. The positioning ties 32 are fastened at approximately 12 inch centers with respect to the drainage quilt 22 by buttons 34, which are anchored at both the first 24 and second 26 surfaces, as shown. The positioning ties 32 are composed of a flexible, yet strong, material such as wire or heavy-duty string. The buttons 34 may be composed of plastic, wood, ceramic, or any other suitable material which prevents the positioning ties 32 from pulling through the drainage quilt 22.
In an alternative embodiment, the drainage quilt 22 is sewn in longitudinal tubes to maintain the generally homogeneous arrangement of drainage members.
Turning now to FIG. 4, another operative context of the drainage quilt 22 is shown. A septic system 36 includes a septic tank 38 which is fed sewage from a house through a sewage line 40. The liquified sewage then flows through a drainage line 42 to a distribution tank 44 which in turn reroutes the wastewater into a leaching field through perforated drainage lines 46. Drainage quilts 22 of the present invention may be placed adjacent the drainage lines 46 to create drainage channels away from the lines 46 and to prevent earth fines from entering the perforated drainage lines.
SUMMARY OF MAJOR ADVANTAGES OF THE INVENTION
After reading and understanding the foregoing inventive drainage quilt, in conjunction with the drawings, it will be appreciated that several distinct advantages of the subject invention are obtained.
Without attempting to set forth all of the desirable features of the instant drainage quilt, at least some of the major advantages of the invention include an aggregate of drainage members 30 disposed within a water permeable membrane in a generally homogeneous arrangement. This arrangement creates random void spacing between the drainage members 30 to permit the passage of ground water. When the drainage quilt 22 is placed adjacent a drainage pipe, as shown in FIG. 1, water may flow through the quilt 22 to reduce hydrostatic pressure build-up at the foundation of a building.
The water permeable feature of the quilt prevents earth fines from transversing the quilt and entering a perforated drainage pipe which would clog a subterranean drainage system. In this connection, a geotextile filter fabric is used to construct a generally rectangular container, readily permitting water to traverse the membrane and percolate through the drainage members 30.
In a preferred embodiment, the drainage members 30, which comprises the bulk mass of the drainage quilt, are composed of recycled expanded polystyrene, recycled chunks of rubber tire material, etc. Due to the composition of the drainage members 30, the drainage quilt is flexible and easy to install and transport. Further, the drainage members 30 will withstand compression loading from backfill sufficient to permit drainage.
Positioning ties 32 operably prevent the drainage quilt 22 from loosing shape or becoming bag-like by retaining the relative positioning of the drainage members 30.
In describing the invention, reference has been made to a preferred embodiment and illustrative advantages of the invention. Those skilled in the art, however, and familiar with the instant disclosure of the subject invention, may recognize additions, deletions, modifications, substitutions, and other changes which will fall within the purview of the subject invention and claims. | A drainage quilt which operably rests adjacent to a subterranean conduit and facilitates water removal and dispersal from underground drainage sites. The drainage quilt includes a water permeable membrane configured in a generally rectangular container and a plurality of drainage members disposed within the container. The drainage members are composed of recycled or new plastic or chunks of old rubber tires and are positioned in a homogeneous fashion to create drainage channels through the subject quilt. Flexible positioning ties extend perpendicularly through the rectangular container to retain the relative positioning of the drainage members. The ties prevent the drainage members from assembling at any one area of the drainage quilt and thus encourage an equal distribution of fluid flow throughout the quilt. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
This application is related to another U.S. patent application entitled "GROMMET ASSEMBLY AND METHOD OF ATTACHING SAME TO A VEHICLE," filed on even date herewith.
BACKGROUND OF THE INVENTION
1. Field of Invention
This invention relates to a grommet. In particular, this invention relates to a two-part grommet assembly that can be attached and removed from a vehicular wall panel.
2. Description of Related Art
Japanese Laid-Open Utility Model Hei 4-137432 discloses a typical grommet assembly. In this grommet assembly, a wire harness 5 is threaded through a hole formed in an appropriate location in a panel 2 of a vehicle, e.g., an automobile. In order to fix the grommet assembly with respect to the vehicle panel 2, a cylindrical member 28 must be inserted into a cylindrical member 24 and a fixed member 22. Once the cylindrical member 28 is fully inserted through the hole, a lip portion of the cylindrical member 24 is expanded to form a mechanical lock with an interior surface of the vehicle panel 2. At the same time, a sealing portion 25 is compressed by a flange 29 to form a seal on the exterior surface of the vehicle panel 2. See FIG. 2. Alternatively, in FIG. 5, screws 16 are provided to attach the grommet 14 to the vehicle panel 2.
This prior art assembly is disadvantageous in that it requires a large force to press the cylindrical member 28 into place. As a result, this type of grommet assembly is not suitable for large scale quantity production. In addition, because the cylindrical member 28 is a separate element, it becomes necessary to perform the inserting operation of the cylindrical member 28 a plurality of times. Thus, the assembly operation is complex.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a grommet easily assembled in an insertion hole of a vehicular body, such as an automobile.
It is a further object of the invention to assemble a grommet assembly using only a small force and a small number of operating parts, so that it is suitable for large scale production.
According to one aspect of the invention, there is provided a grommet assembly for a vehicle comprising a main grommet body having a centrally located wire harness aperture, a first surface including a sealing portion and a second surface opposite to the first surface, and an elastic spring member that applies a pressing force on the second surface.
In some embodiments of the invention, the elastic spring member is a metallic wire spring having a round cross-section. In addition, the sealing portion may include sealing lips and the elastic spring member may be aligned with the sealing lips. The grommet assembly may further include a hollow cylindrical extension protruding from the second surface that is aligned with the wire harness aperture. The grommet assembly may further include structure for maintaining the elastic spring member in close relation to the second surface prior to assembly. This structure may include a disk shaped brim or a plurality of blade members extending radially away from the hollow cylindrical extension. The grommet assembly may further include structure for uniformly distributing the pressing force from the elastic spring member to the main grommet body. This structure may include a rigid plate member interposed between the elastic spring member and the main grommet body, or a wavelike formation formed as part of the elastic spring member that contacts the second surface. Furthermore, the grommet assembly may include structure for supporting the elastic spring member in substantial alignment with the main grommet body prior to assembly. This structure may include at least one projection extending perpendicular to the second surface, a medium sized cylindrical portion formed as part of the hollow cylindrical extension, or it may be in the form of a modified bracket which includes a support surface for supporting the elastic spring member.
In some other embodiments, including those mentioned above, the elastic member may include a wire spring having open and closed ends opposite to one another. The open end may define a first bracket engaging part that engages with the first bracket mounted on a vehicle panel and the closed end may define a second bracket engaging part that engages with a second bracket mounted on a vehicle panel. The grommet assembly may further include a rigid plate member interposed between the main grommet body and the elastic spring member, and the rigid plate member may comprise a substantially U-shaped member, wherein an open end of the U-shaped rigid plate member has a width at least equal to a diameter of a hollow cylindrical portion of the main grommet body that extends away from the second surface.
According to a second aspect of the invention, there is provided a grommet assembly for attachment to a wall panel of a vehicle, comprising a main grommet body including structure for forming a waterproof seal with the wall panel and structure for applying a pressing force on the main grommet body opposite to where the waterproof seal is formed.
These and other aspects and salient features of the present invention will be described in or apparent from the following detailed description of preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention will be described with reference to the following drawings, wherein:
FIG. 1 illustrates a perspective view of a two-part grommet assembly according to an embodiment of the present invention;
FIG. 2 illustrates a cross-section of the two-part grommet assembly of FIG. 1;
FIGS. 3-5 illustrate an assembly process for assembling the FIG. 1 grommet assembly to a vehicular wall panel;
FIG. 6 illustrates a perspective view of the FIG. 1 grommet assembly in its assembled position;
FIG. 7 illustrates a perspective view of a modified wire spring according to the present invention;
FIG. 8 illustrates a wire spring according to another embodiment of the present invention;
FIG. 9 illustrates a wire spring according to yet another embodiment of the present invention;
FIG. 10 illustrates a side view of the wire spring shown in FIG. 9;
FIG. 11 illustrates a grommet assembly according to yet another embodiment of the present invention;
FIG. 12 illustrates a side view of the grommet assembly as shown in FIG. 11;
FIG. 13 illustrates a modified wire spring according to the present invention;
FIG. 14 illustrates a modified bracket according to the present invention;
FIG. 15 shows a side view of a wire spring according to FIG. 13 in its assembled position;
FIG. 16 illustrates a partial cross-section of a modified wire spring and modified bracket according to the present invention;
FIG. 17 illustrates a perspective view of the modified bracket shown in FIG. 16;
FIG. 18 illustrates a modified main grommet body according to the present invention;
FIG. 19 illustrates yet another modified main grommet body according to the present invention;
FIG. 20 illustrates still another modified version of the main grommet body according to the present invention;
FIG. 21 illustrates still another embodiment of the main grommet body according to the present invention;
FIG. 22 illustrates yet another modified main grommet body according to the present invention;
FIG. 23 illustrates a rigid plate member interposed between a wire spring and main grommet body according to the present invention;
FIG. 24 illustrates a side view of the assembly shown in FIG. 23;
FIG. 25 illustrates a detail view of the rigid plate member of FIGS. 23 and 24;
FIG. 26 is a reverse perspective view of the rigid plate member shown in FIG. 25;
FIG. 27 is a perspective view of a modified two-part rigid plate member according to the present invention;
FIG. 28 is a side view of the two-part rigid plate assembly as shown in FIG. 27;
FIG. 29 is an exploded view of the grommet assembly as shown in FIG. 27;
FIG. 30 is a perspective view of a modified wire spring according to the present invention;
FIG. 31 is a perspective view of the modified wire spring as shown in an assembled position;
FIG. 32 illustrates another two-part grommet assembly according to the present invention prior to attachment to a vehicular wall panel;
FIG. 33 illustrates a side view of the grommet assembly according to FIG. 32;
FIG. 34 illustrates an enlarged detail view of the pivotable arm according to the present invention;
FIG. 35 illustrates a reverse perspective view of the rigid plate member shown in FIGS. 32 and 33;
FIG. 36 is an elevation view of the rigid plate member according to the present invention; and
FIG. 37 is a plan view of the rigid plate member according to the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIGS. 1-6 illustrate a first embodiment of the present invention. In FIG. 1, a two-part grommet assembly 10 includes a main grommet body 100 and a pressing member in the shape of an elastic spring member in the form of a wire spring 200 made of a suitable metal, plastic or other material. The main grommet body 100 is made from a resilient material, e.g., rubber, and is shown as having a generally cylindrical shape. As shown in FIG. 2, the main grommet body 100 is provided with a centrally located aperture or opening 116 defined by a hollow cylindrical extension 106. The main grommet body includes a first surface 102 that includes a sealing portion including sealing lips 110. A flange 112 is located radially inside the sealing lips 110. A radial connector 114 connects the hollow cylindrical extension 106 to the outer section of the main grommet body 100. Opposite to the first surface 102 is a second surface 104. The first surface 102 and the second surface 104 are connected by a circumferential side surface 108.
The wire spring 200 includes an open end 201 and a closed end 203. The open end 201 includes two leg portions 202, and the closed end 203 includes two L-shaped leg portions 206 that are connected by a lateral connecting member 208. The open and closed ends 201, 203 overhang (i.e., extend beyond) the circumferential side surface 108 of the main grommet body 100. In addition, the open and closed ends 201, 203 are connected using semicircular portions 204 that rest against the second surface 104 of the main grommet body 100. In addition, the semicircular portions 204 contact the second surface 104 of the main grommet body 100 at a point substantially opposite to where the sealing lips 110 are formed on the first surface 102 of the main grommet body 100. As shown in FIG. 2, the lateral connecting member 208 has a round cross-section. The cross-section of the entire wire spring 200 also has a substantially round cross-section.
FIGS. 3-5 show a process for attaching the two-part grommet assembly 10 to a vehicular wall panel 14. The vehicular wall panel 14 includes an aperture 13 into which the main grommet body 100 is inserted. A wire harness 12 comprising a group of bundled wires is inserted through the aperture 116 (FIGS. 1 and 2) provided in the hollow cylindrical extension 106. A taped portion 20 may be provided to further enhance the waterproofing capability of the grommet assembly 10. The flange 112 of the main grommet body 100 protrudes partially within the opening 13 provided in the vehicular wall panel 14. At the same time, the sealing lips 110 come into light contact with an exterior surface 14e of the vehicular wall panel 14.
The wire spring 200 is attached to first and second brackets 16, 18 to firmly secure the main grommet body 100 against the exterior surface 14e of the wall panel 14. Initially, the two leg portions 202 of the open end 201 of the wire spring 200 are expanded (each is moved laterally) or twisted (one is moved forward, the other is moved rearward) such that the spacing between the leg portions 202 becomes greater than the diameter of the hollow cylindrical extension 106. This enables the wire spring 200 to fit over the hollow cylindrical extension 106. However, expansion of the leg portions 202 is unnecessary if the wire harness 12 is inserted into the aperture 116 after the wire spring 200 is attached to the main grommet body 100. In other words, the spacing between the semicircular portions 204 is greater than the diameter of the hollow cylindrical extension 106 such that the wire spring 200 can easily fit over the hollow cylindrical extension 106. In FIG. 3, the wire spring 200 is supported by the hollow cylindrical extension 106.
From the position shown in FIG. 3, the wire spring 200 is raised until the distal end portions of the two leg portions 202 engage with the first bracket 16, which is provided on (e.g., welded or affixed to) the wall panel 14. This position is shown in FIG. 4. After reaching the position shown in FIG. 4, the wire spring 200 is pivoted in the direction of an arrow A shown in the top portion of FIG. 4. The wire spring 200 is pivoted in the direction of the arrow A until reaching the position shown in FIG. 5, which shows the wire spring fixed in locked relation with respect to the second mounting bracket 18 also provided on (e.g., welded or affixed to) the vehicular wall panel 14.
As shown in FIG. 6, the first mounting bracket 16 has a simple construction and includes an S-shaped bracket that maintains the two leg portions 202 in a fixed position with respect to the wall panel 14. The second bracket 18 is an arrow shaped member including an enlarged head portion 17 and a reduced thickness portion 19. When pivoting the wire spring 200 from the position shown in FIG. 4 to the position shown in FIG. 5, the L-shaped leg portions 206 are deformed so as to expand by virtue of being pressed against the arrow shaped portion 17. In this respect, placement of the lateral connecting member 208 helps allow the L-shaped leg portions expand to overcome the size of the arrow shaped head portion 17. Also, the lateral connecting member 208 serves as a handle that is spaced from the second surface 104 when in the assembled position. However, it is not necessary for the closed end 203 of the wire spring 200 to include an L-shaped formation because the lateral connecting member 208 can be provided in the same plane as the rest of the wire spring 200.
In any event, the L-shaped leg portions 206 are expanded until reaching the reduced thickness portion 19. At that point, the L-shaped leg portions 206 return to their normal spacing, which is less than the width of the arrow shaped head portion 17. Accordingly, the closed end 203 of the wire spring 200 will be fixed in place with respect to the second bracket 18 and the vehicular wall panel 14. Also, because the open end 201 of the wire spring 200 is fixed to the first bracket 16, pivoting of the wire spring into its closed position will apply a pressing force to the second surface 104 of the main grommet body 100. As a result, the main grommet body 100 is compressed such that the sealing lips 110 provide a tight (preferably waterproof) seal against the exterior surface 14e of the wall panel 14.
With the two-part grommet assembly as shown in FIGS. 1-6, it is not necessary to access or modify an interior surface 14i of the wall panel 14. In addition, because of the simplicity in attaching the wire spring to apply the pressing force against the main grommet body 100, the assembly operation can be quickly and easily performed. In addition, because the semicircular portions 204 are substantially aligned with the sealing lips 110, the pressing force is directly applied to enhance the sealing performance between the first surface and the exterior surface of the wall panel 14. In addition, because the pressing force is evenly distributed along the semicircular portions 204, the sealing function is uniformly distributed substantially about the circumference of the main grommet body 100. Furthermore, the grommet assembly can be detached from the vehicular wall much more easily than prior art grommets.
As shown in FIGS. 1-6, the wire spring 200 is shown as having an annular or round cross-section. However, other cross-sectional shapes are also within the scope of the invention so long as a uniform pressing force can be applied to the main grommet body 100. For example, as shown in FIG. 7, a wire spring 200' includes a rectangular cross-section that can be manufactured, for example, using a conventional stamping process.
FIG. 8 shows a modified example of a wire spring 210. The wire spring 210 includes a modified closed end 212 and a modified open end 214. Because the closed end is substantially triangular in shape, the spacing between the L-shaped leg portions 216 is very small such that the pressure distribution is more evenly distributed along the entire circumference of the main grommet body 100. In addition, the open end 214 is substantially triangular in shape such that the spacing of the leg portions 218 of the open end 214 is also small to more uniformly distribute the pressing force.
FIG. 9 illustrates yet another modified version of a wire spring 220 according to the present invention. In this wire spring, the semicircular portions are shown to include a wavelike formation 222. The wavelike formation 222 more uniformly applies the pressing force on the second surface 104 of the main grommet body 100. Thus, even if the shape of the wire spring does not exactly match the shape of the main grommet body, the waterproofing capability is maintained. Thus, manufacturing tolerance requirements are low, and the shapes of the main grommet body 100 and the wire spring 220 need not match as precisely. FIG. 10 shows a side view of the wire spring 220 shown in FIG. 9. As shown in FIG. 10, the wire spring 220 includes a slightly arched shape so as to increase the pressing force applied to the second surface 104 of the main grommet body 100.
FIGS. 11 and 12 show a two-part grommet assembly similar to that shown in FIG. 1. However, the grommet assembly includes a wire spring 230 which is slightly different from that shown in FIG. 1. As shown in FIG. 12, the wire spring 230 includes a shape such that the open and closed ends 201', 203' of the wire spring 236 are bent towards the vehicular wall panel 14 in the assembled position. With this structure, the circumferential edge portion 108 of the main grommet body 100 is compressed to enhance the sealing effect between the sealing lips 110 and the exterior surface of the vehicular wall panel 14. Thus, the thickness T in the center of the main grommet body 100 is larger than the thickness t at the circumferential side surface 108 of the main grommet body 100. The wire spring 230 can be preformed in the shape shown in FIG. 12. However, the wire spring 230 could also be bent to create the shape shown in FIG. 12 by providing brackets 16 and 18 which are shorter than those shown in FIGS. 3-6. In either case, the effect of the structure shown in FIG. 12 is to compress the circumferential side surface 108 of the main grommet body 100 which also expands the diameter of the main grommet body 100.
FIG. 13 shows a modified version of a wire spring 240. The wire spring 240 includes a pair of bent portions 242 provided at the open end 201" of the wire spring 240. The bent portions 242 of the wire spring 240 are structured to cooperate with a modified bracket 16' shown in FIG. 14. The modified bracket 16' includes a hole 15 dimensioned to receive the bent portions 242 of the wire spring 240. The assembly process is similar to that shown in FIGS. 3-5, only the bent portions 242 are inserted into the hole 15 to achieve the assembled position shown in FIG. 15. The modified bracket 16' ensures that the open end of the wire spring 240 cannot rotate with respect to the bracket 16', thus facilitating assembly and ensuring that the pressing force is maintained against the main grommet body 100. Furthermore, in the process of attaching the two-part grommet assembly 10 to the vehicular wall panel 14 in the step shown in FIG. 4, if an assembly worker accidentally pulls the wire spring 200 in the extension line direction of the closed end 203, i.e., the upward direction, the open end 201 may become detached from bracket 16. However, in this modified example, the bent portions 242 of the modified wire spring 240 are engaged with the bracket 16' so that the open end will not detach. Therefore, the assembly process becomes easy.
FIG. 16 shows a modified bracket 160 which includes the same basic structure as the mounting bracket 16' shown in FIG. 14. However, the mounting bracket 160 includes an L-shaped support wall 162 that is spaced opposite to where the hole 15 for the bent portion 242 of the leg is inserted. A recess 164 is created between the support wall 162 and the insertion hole 15. With this structure, the support wall 162 receives and supports the bent portion 242 of the wire spring 240. Thus, the wire spring 240 is prevented from descending and is maintained in substantial alignment with the second surface 104 of the main grommet body 100. This arrangement further facilitates the assembly process by holding the open end of the wire spring in place while the closed end of the wire spring is secured, e.g., by being snapped into place over the arrow shaped head portion 17. As shown in FIG. 16, the modified bracket 160 includes a surface 168 adapted for mounting to a vehicular wall panel 14. Also, FIG. 17 shows the modified bracket 160 as including a reinforcement 166 that helps maintain the bracket 160 in a predetermined shape.
FIGS. 18-22 show grommet modifications that assist in maintaining the wire spring in place during assembly. These modifications further ease the assembly process.
FIG. 18 shows the main grommet body 100 as including a brim 130. The brim 130 is a substantially disk shaped member and is attached to the circumferential surface of the hollow cylindrical extension 106. The brim 130 has an inner surface 131 that faces the second surface 104 of the main grommet body 100 and defines a gap G between the inner surface 131 and the second surface 104 within which the wire spring 200 can move prior to assembly.
FIG. 19 shows a modified version of the brim shown in FIG. 18. In FIG. 19, a plurality of substantially flat blade members 140 define a gap G within which the spring 200 can move prior to assembly. In both FIGS. 18 and 19, installation of the grommet assembly is facilitated because the wire spring 200 is maintained in close proximity to the main grommet body 100.
FIG. 20 shows a main grommet body 100 that includes a medium sized diameter portion 107 provided between the hollow cylindrical extension 106 and the main grommet body 100. The medium sized diameter portion 107 maintains the wire spring 200 in substantial alignment with the second surface 104 of the main grommet body 100 in a position opposite to where the sealing lips 110 are positioned on the first surface 102 of the main grommet body 100. In addition, a plurality of substantially planar blade members 140' may be circumferentially disposed about and substantially between the hollow extension 106 and the medium sized diameter portion 107. The blade members 140' have substantially the same function as the brim 130 (FIG. 18) and the blade members 140 (FIG. 19).
FIG. 21 illustrates a main grommet body 100 including a plurality of projections 150 extending away from the second surface 104 and parallel to the hollow cylindrical extension 106. The blade members 150 have the same function as the medium sized diameter portion 107 (FIG. 20), i.e., to maintain the wire spring 200 in substantial alignment with the main grommet body 100. In both cases, the wire spring 200 is prevented from descending. As compared to the operation shown between FIGS. 3 and 4, it is not necessary to raise the wire spring 200 to engage the open end with the bracket 14. Thus, engagement and assembly of the wire spring 200 is made easier than the embodiment shown in FIGS. 1-6.
Each of the projections 150 may also include a brim portion 140". The function and effect of the brim portions 140" are substantially identical to the brim 130 (FIG. 18) and the blade members 140 (FIG. 19) and 140' (FIG. 20).
FIG. 22 illustrates a main grommet body 100 which includes a planar guide member 170 extending from the hollow cylindrical portion 106 to the second surface 104. The guide member 170 may have a circular arc shape and can be positioned between the L-shaped leg portions 206 to properly prealign the wire spring 200 with respect to the main grommet body 100. Accordingly, the open and closed ends 201,203 of the wire spring can be easily engaged with the brackets 16 and 18.
The guide member 170 can be used in combination with the brims of FIGS. 18-21.
FIGS. 23-26 show another embodiment of the present invention. FIG. 23 shows a substantially rigid plate member 300 interposed between the wire spring 200 and a main grommet body 100'. The rigid plate member 300 can be made of metal or synthetic resin and includes a rim portion 302 that extends about the circumferential side surface 108 of the main grommet body 100'. FIG. 24 shows a side view of the assembly shown in FIG. 23. The rim portion 302 includes an inner projection 304 that is inserted within a radial recess 124 provided on the main grommet body 100'. FIG. 26 illustrates a partial reverse perspective view of the rigid plate member 300 including the inner projection 304. The rim portion 302 and inner projection 304 hold the rigid plate member 300 in place on the main grommet body 100'.
Due to the presence of the rigid plate member 300, the pressing force applied from the wire spring 200 to the main grommet body 100 is more evenly distributed. Accordingly, waterproofing of the grommet assembly is made more uniform.
As shown in FIG. 25, the rigid plate member 300 is an upside-down U-shaped member. The rigid plate member 300 includes ends 306 which are spaced apart a distance S. The distance S is dimensioned such that it is equal to or larger than the diameter d of the hollow cylindrical extension 106. Accordingly, the rigid plate member 300 can be slipped between the wire spring 200 and the main grommet body 100' even if the wire harness 12 is previously inserted within the opening 116 of the hollow cylindrical extension 106.
FIGS. 27-29 illustrate an alternative arrangement for the rigid plate member. As shown in FIG. 27, the rigid plate member is a two-part assembly including a first piece 310 and a second piece 312. The second piece 312 includes a lower engaging part 318, and the first piece 310 includes an upper engaging part 320. The upper engaging part 320 is engaged within a recess of the second piece 312, and the lower engaging part 318 is received within a recess formed in the first piece 310.
As shown in FIG. 28, the first piece 310 includes a bent portion 316, and the second piece 312 includes a bent portion 314. The bent portions 314 and 316 fit within corresponding radial recesses 124 provided in a main grommet body 100". FIG. 29 is an exploded view of the two-part rigid plate assembly and illustrates the radial recesses 124 which receive the bent portions 314 and 316 of the first and second pieces 310 and 312. Other shapes for the first and second pieces 310, 312 are also within the scope of the invention so long as they collectively cover substantially the entire pressure receiving portion of the second surface 104 of the main grommet body 100".
FIG. 30 shows a metallic wire spring 250 constituting the pressing member of the two-part grommet assembly. The wire spring 250 includes a substantially circular inner member 252 and a substantially rectangular outer member 254. The inner member 252 contacts the second surface 104 of the main grommet body and the outer member attaches to brackets 16 and 18' formed on the vehicular wall panel 14. The brackets 16 shown in FIG. 30 are similar to the bracket 16 shown in FIGS. 3-5. However, the bracket 18' is a U-shaped member structured to receive a hook portion 258 that is formed as an integral part of the outer member 254. To attach the wire spring 250 to the main grommet body 100, a pair of connector legs 260 are twisted to expand the distance between the leg portions 260 to a distance that is greater than the diameter of the hollow cylindrical extension 106. the opposed arrows A in FIG. 30 illustrate the expansion. However, the wire spring 250 can be preassembled to the main grommet body 100 before the wire harness 12 is inserted within the hollow cylindrical extension 106. In either assembly process, the inner member 252 is set to lightly rest against the second surface 104 in the position shown in FIG. 30. At this point, a pair of double looped bracket engaging portions 256 are engaged with the brackets 16.
In the position shown in FIG. 30, the inner member 252 is in a first plane parallel to the plane in which the second surface 104 is located. The outer member 254 is provided in a plane disposed at an angle with respect to the plane of the inner member 252. The outer member is then pivoted in the direction of the top arrow B to engage the hook portion 258 with the bracket 18'. During this operation, the wire spring 250 is easily bent such that the spring energy stored in the relaxed position is converted into a pressing force which maintains the seal between the main grommet body 100 and the wall panel 14. FIG. 31 shows the outer member 254 after it has been pivoted into the assembled position.
FIGS. 32-37 illustrate another two-part grommet assembly according to the present invention. Like the previously described grommet assembly embodiments, the embodiment of FIGS. 32-37 includes a main grommet body and a pressing member that applies a force to the main grommet body.
As shown in FIG. 32, the two-part grommet assembly includes a main grommet body 400 and pressing member including a rigid plate member 404. The main grommet body 400 can be similar to the main grommet body described in previous embodiments. The rigid plate member 404 includes at least one tabbed hinge portion 402. In FIG. 32, a pair of tabbed hinge portions 402 are provided. A pivotable pressing member 401 is attached to the tabbed hinge portions 402.
The pivotable pressing member 401 includes an arm portion 410 that is attached via a hinge 416 to each tabbed hinge portion 402. The pivotable pressing member 401 is pivotal between a first position to apply a pressing force to seal the main grommet body 400 against a vehicular wall panel 422 and a second position to release the pressing force.
The pivotable pressing member 401 includes a handle or gripping portion 414 attached to the arm portions 410 and a hook portion 412 opposite to the gripping portion 414. The hinge 416 serves as a fulcrum and is located between the gripping portion 414 and the hook portion 412.
As shown in FIG. 32, the two-part grommet assembly is inserted into an opening 420 provided in the vehicular wall panel 422. The hook portions 412 are aligned with bracket portions 418 mounted on the vehicular wall panel 422.
FIG. 33 shows the grommet assembly and harness 12 after insertion thereof within the opening 420. From this position, the pivotable pressing member 401 is pivoted along a path shown by the arrow A into a position shown in the phantom dot and dash line. During pivoting action, each hook portion 412 engages with its respective bracket 418. At that time, a pressing force from the rigid plate member is applied from a second surface 426 to a first surface 428 of the main grommet body 400 which includes sealing lips 430. The sealing lips 430 form a waterproof seal with an external surface 422e of the vehicular wall panel 422.
As shown in FIG. 34, the hook portion 412 comprises a cam member having a width in the plane of the paper that increases from the distal end 411 thereof towards a proximal end 415 thereof adjacent the hinge 416 (FIG. 33). After pressing the sealing lips 430 to the vehicular wall panel 422, when the pressing member 401 is rotated toward the vehicular wall panel 422, the bracket 418 and the inside surface 413 are in an overlapped relationship shown by the dashed (phantom) line. The overlapping measurement t ranges between 0.5 millimeters and 1.5 millimeters. Preferably, the overlap is 1.0 millimeters. With this structure, the distal end 411 having a narrow width can fit between the bracket 418 and the vehicular wall panel 422. However, as the pivotable pressing member 401 is pivoted into the engaged position, the width of the hook portion 412 increases such that an inside surface 413 of the hook portion 412 adjacent the bracket 418 engages with the bracket 418. A pressing force gradually develops between the inside surface 413 of the hook portion 412 and the bracket 418. The pressing force is transferred to establish firm contact between the sealing lips 430 and the exterior surface 422e of the vehicular wall panel 422.
FIG. 35 shows a detail reverse perspective view of the rigid plate member 404. The rigid plate member 404 is similar to the rigid plate member 300 shown in FIG. 26 and includes a rim 425 and bent portions 427 that engage with recesses provided or formed in the main grommet body 400. FIGS. 36 and 37 illustrate, respectively, elevation and plan views of the rigid plate member 404. In FIG. 37, the rigid plate member 404 has a shape approximating an upside-down U. Ends 424 of the rigid plate member 404 define a space S which is larger than a diameter d of a hollow cylindrical member or extension 417. Accordingly, like the rigid plate member 300 shown in FIG. 25, the rigid plate member 404 can be fit into place even after the wire harness 12 is installed into the main grommet body 400.
The invention has been described with reference to preferred embodiments thereof, which are intended to be illustrative, not limiting. Various modifications can be made to the above preferred embodiments without departing from the spirit or scope of the invention as defined in the appended claims. | A grommet assembly has a main grommet body including first and second surfaces opposite one another. The first surface includes a sealing portion. An elastic pressing member operatively associated with the main grommet body applies a pressing force to the second surface. The elastic pressing member may attach to brackets provided on an exterior wall of a vehicle, e.g., an automobile. The grommet assembly may include a rigid plate member disposed between the elastic pressing member and main grommet body. The grommet assembly may include structure for substantially preventing relative rotation between the main grommet body and the elastic pressing member, structure for uniformly distributing the pressing force from the elastic pressing member to the main grommet body, and structure for supporting the elastic member in substantial alignment with the grommet body prior to assembly. | 5 |
FIELD OF THE INVENTION
[0001] The invention relates to suture passing surgical instruments. More specifically, the invention relates to a hand instrument and method for passing suture through tissue.
BACKGROUND OF THE INVENTION
[0002] Arthroscopic surgery often requires a surgeon to attach a length of suture material remotely to an internal body part. For example, a suture is passed through a detached tendon and is then secured to a hole or anchored in a bone. Various instruments have been developed for this purpose, many of them having an elongate configuration and low profile for facilitating use through cannulas in less invasive surgery. These devices have also typically have opposing jaws, which clamp onto either side of the tissue to be sutured. However, the various known mechanisms and configurations for loading the suture, grasping the suture, and threading a suture between the jaws shown in these prior art devices are exceedingly complex. Moreover, due to this complexity and poor design, in general, these devices have a tendency to create tangles in the suture or to simply fail to pass the suture through the tissue as intended. Many of these devices may also require the use of both hands to operate the instrument.
[0003] What is desired, therefore, is a suture passing device having a low profile that can accommodate many thicknesses of tissue, is easy to load with a suture and utilizes a mechanism that is easy and reliable for threading the suture through tissue.
SUMMARY OF THE INVENTION
[0004] Accordingly, it is an object of the present invention to provide a suture passing instrument that is of simple configuration so that a suture may be loaded into the instrument with relative ease. It is a further object of the present invention to provide a suture passing instrument having wide opening jaws so that it may be used with a range of tissue thickness. It is a further object of the invention to provide a suture passing instrument which prevents tangling of the suture and only threads one loop of suture through the tissue as desired. A further object of the invention is to provide a suture passing instrument which may be operated with one hand.
[0005] These and other objectives are achieved by providing a suture passing instrument comprising a first jaw coupled to an end of an elongated shaft, a second jaw coupled to the first jaw, and formed with a holder for supporting a suture, and a needle slidably disposed within the first jaw, the needle having a hook on a side for releasably capturing a portion of a suture. The first jaw defines a channel for receiving the needle and a ramp for deflecting the needle transversely of the shaft when advanced to an extended position. In some embodiments, the first jaw is stationary and the second jaw is movable and may be pivotally coupled to the first jaw. The needle may be made from a malleable material and may have a sharp distal tip for piercing tissue. An opening may also be formed in the second jaw that provides a clearance for a tip portion of the needle to pass when it is advanced to its extended position.
[0006] In some embodiments, the opening and the holder may be aligned such that a suture received in the holder extends across the opening. In further embodiments, the holder supports the suture on an inner surface of the movable jaw facing the stationary jaw. The holder may comprise at least one slot formed on an edge of the movable jaw which, in further embodiments, may comprise a first slot formed on a distal edge of the movable jaw and a second slot formed on an adjacent edge of the movable jaw. The second slot may be T-shaped. In further embodiments, a plurality of needles may be slidably disposed within the first jaw. In yet further embodiments, the elongated shaft may be semi-rigid or hinged.
[0007] Other objects of the present invention are achieved by provision of a suture passing instrument comprising a stationary jaw coupled to an elongated shaft, a malleable needle slidably disposed within the stationary jaw, the needle having a distal tip and a hook on an edge for releasably capturing a portion of a suture, a movable jaw pivotally coupled to the stationary jaw, and formed with a holder for supporting a suture and an opening that provides a clearance through which a tip portion of the needle passes when in its extended position, a first actuating member coupled to the movable jaw for moving it between a closed position alongside the stationary jaw and an open position spaced therefrom, and a second actuating member coupled to said needle for moving the needle between a recessed position and an extended position wherein the distal tip of the needle is deflected by the ramp and extends out of the stationary jaw transversely of the shaft such that the needle tip enters the opening in the movable jaw and the needle hook captures a portion of the suture supported in the holder. The stationary jaw may define an internal channel for receiving the needle and a distal ramp.
[0008] Other objects of the present invention are achieved by provision of a method of passing suture comprising the steps of providing a suture passing instrument having a first jaw coupled to an elongated shaft, a second jaw coupled to the first jaw, and formed with a holder for supporting a suture, and a needle slidably disposed within the first jaw, the needle having a hook on a side for capturing a portion of a suture; loading a suture into the holder of said second jaw; grasping tissue between said first jaw and second jaw; and passing suture through said tissue by advancing said needle to its extended position, capturing a portion of the suture supported in the holder with the hook, and returning the needle to a recessed position so that a loop of the suture portion captured by the needle is drawn through the tissue. The first jaw may define a channel for receiving the needle and a distal ramp for deflecting the needle transversely of the shaft when advanced to an extended position.
[0009] In some embodiments, the step of grasping tissue between the first jaw and second jaw further includes actuating a first actuating member displaced within the shaft and coupled to the second jaw such that the second jaw pivots toward the first jaw to grasp tissue therebetween. In further embodiments, the step of advancing the needle further includes actuating a second actuating member displaced within the shaft and coupled to the needle such that the distal tip of the needle is advanced proximally, is deflected by the ramp and extends out of the first jaw transversely of the shaft. The step of advancing the needle may include advancing the needle through tissue. In still further embodiments, the step of advancing the needle includes advancing the needle such that the needle tip enters the opening in the second jaw.
[0010] Other objects of the invention and its particular features and advantages will become more apparent from consideration of the following drawings and accompanying detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a perspective view of one embodiment of the suture passing instrument of the present invention.
[0012] FIG. 2 is a top view of one embodiment of the suture passing instrument of the present invention.
[0013] FIG. 3 is a sectional side view of one embodiment of the suture passing instrument of the present invention, taken along line B.
[0014] FIG. 4 is a side view of one embodiment of the suture passing instrument of the present invention.
[0015] FIG. 5 is a perspective view of the jaw portion of one embodiment of the suture passing instrument of the present invention.
[0016] FIG. 6 is a perspective view of the jaw portion of one embodiment of the suture passing instrument of the present invention.
[0017] FIG. 7 is a perspective view of the jaw portion of one embodiment of the suture passing instrument of the present invention.
[0018] FIG. 8 is a perspective view of the jaw portion of one embodiment of the suture passing instrument of the present invention.
[0019] FIG. 9 is a perspective view of the jaw portion of one embodiment of the suture passing instrument of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0020] One embodiment of the suture passing instrument 10 of the present invention is shown in FIG. 1 . Suture passing instrument 10 includes a shaft 12 connecting a proximally disposed handle portion 14 to a distally disposed jaw portion 16 . Shaft 12 may be semi-rigid or hinged along its length so that it can be bent or angled once the suture passing instrument 10 is inserted in a trocar (not shown). This allows a user to adjust the jaw portion 16 at different angles to reach the desired area. Jaw portion 16 includes an upper jaw 18 pivotally connected to a stationary lower jaw 20 , which may be formed integral with the shaft 12 . Alternatively, upper jaw 18 may be pivotally connected directly to the shaft 12 . The distal end 22 of lower jaw 20 is provided as a curved portion 24 .
[0021] As shown in FIGS. 2 and 3 , upper jaw 18 includes a holder 26 , which comprises at least one slot, for supporting a suture (not shown). In the present embodiment, the holder 26 comprises a first slot 28 formed on the distal edge 30 of the upper jaw 18 and a second slot 32 formed on an adjacent edge 34 . Second slot 32 may be provided in the shape of a “T”, having bar 36 , which aids in supporting the suture within the holder. An opening 38 is also provided on second slot 32 , the utility of which will be described below. Preferably, bar 36 and the first slot 28 both lie along an axis A. More preferably, bar 36 , first slot 28 , and opening 38 all lie along axis A. Axis A may, but need not, be the same as axis B, which bisects shaft 12 . The inner surface 39 of upper jaw 18 may also be provided with a plurality of ridges 40 to aid in gripping tissue between the jaws.
[0022] Suture passing instrument 10 also comprises a needle 42 . Preferably, needle 42 is flexible and may be composed of spring stainless steel or nitinol. Depicted in FIG. 7 , needle 42 is provided with a sharp tip 90 for piercing tissue and a hook 92 on an edge for capturing a suture, as will be described below. Needle 42 is disposed within an internal channel 44 which runs the length of shaft 12 and continues into the lower jaw 20 . Corresponding to the curved portion 24 of lower jaw 20 , internal channel 44 is provided with a ramp 46 , the utility of which will be explained below. In additional embodiments, multiple needles may be disposed within internal channel 44 , or individually within multiple channels. Accordingly, upper jaw 18 would be provided with multiple holders for supporting a suture so that multiple suture loops could be passed at one time.
[0023] Handle portion 14 comprises a trigger arm 48 and a stationary arm 50 , both terminating in finger grips 52 , 54 , and a spring loaded push button 56 . Spring 58 biases push button 56 in an inactive position. As shown in FIG. 3 , a first actuator 60 is coupled at a proximal end 62 to trigger arm 48 and at a distal end 64 to upper jaw 18 . When trigger arm 48 is moved in the direction of arrow A (shown in FIG. 4 ), upper jaw 18 pivots around pivot point 66 in the direction of arrow B from an open position 68 to a closed position 70 . This allows for a user to grasp an object, namely tissue, between the jaws 18 , 20 by squeezing trigger arm 48 . Moreover, the ample clearance provided when upper jaw 18 is in the open position 68 allows a user to grasp tissue of many thicknesses.
[0024] A second actuator 72 is coupled at a proximal end 74 to push button 56 and at a distal end 76 to needle 42 . Depressing push button 56 in the direction of arrow C, distally advances needle 42 from a recessed position 78 (shown in FIG. 3 ) to an extended position 80 (shown in FIG. 4 ), where it extends out of outlet 82 to channel 44 . Ramp 46 deflects needle 42 so that it exits channel 44 transverse of the shaft 12 . As shown in FIG. 3 , outlet 82 is vertically aligned with opening 38 when upper jaw 18 is in its closed position 70 . Thus, when needle 42 is in its extended position, it extends into opening 38 . Both first 60 and second 72 actuators are disposed within internal channel 44 .
[0025] Notably, a user can grasp the instrument and actuate trigger arm 52 with the fingers of one hand through finger loops 52 , 54 , leaving the thumb free to actuate push button 56 so that only one hand is necessary to operate the instrument. This leaves the user's other hand free to manipulate the suture threaded in the tissue or to perform other tasks.
[0026] In operation, a suture 84 is first loaded into holder 26 by sliding it into first 28 and second 32 slots, as shown in FIG. 5 , so that a portion 86 of suture 84 lies across the inner surface 39 of upper jaw 18 . As noted above, bar 36 , first slot 28 , and opening 38 preferably lie along a single axis A so that suture portion 86 lies squarely across opening 38 . Jaws 18 , 20 are then placed on either side of tissue 88 intended to be sutured. Upper jaw 18 is moved into a closed position 70 , as shown in FIG. 6 , clamping the tissue 88 between the lower and upper jaws.
[0027] Needle 42 is advanced to its extended position 80 , piercing tissue 88 as it passes through outlet 82 and into opening 34 , passing by suture portion 86 (shown in FIG. 7 ). When push button 56 is released, needle 42 then withdraws back through opening 38 and hook 92 catches suture portion 86 . As shown in FIG. 8 , as needle 42 continues to recede in a proximal direction, suture portion 86 is threaded through tissue 88 forming a suture loop 94 . The suture portion 86 is held by the hook 92 against the distal end 22 of lower jaw 20 as the user opens the jaws 18 , 20 to release the tissue 88 . The trailing ends of suture 84 are then released from holder 26 and the suture loop 94 is released by advancing needle 42 until the suture can clear the hook 92 ( FIG. 9 ). If desired, the user may pull one side of the suture loop 94 through the tissue 88 so that one end of the suture lies on either side of the tissue.
[0028] Notably, the length and configuration of the needle 42 is such that it only passes into opening 34 far enough to capture suture portion 86 . If needle 42 were allowed to advance such that all of hook 92 extended through opening 34 , it would be more likely to capture another portion of suture 84 in addition to suture portion 86 . This would cause the suture 84 to become tangled and or for more than one suture portion to be passed through the tissue, which is undesirable.
[0029] It should be understood that the foregoing is illustrative and not limiting, and that obvious modifications may be made by those skilled in the art without departing from the spirit of the invention. Accordingly, reference should be made primarily to the accompanying claims, rather than the foregoing specification, to determine the scope of the invention. | A method for passing suture through tissue and a suture passing instrument having a first jaw coupled to an end of an elongated shaft, a second jaw coupled to the first jaw, and formed with a holder for supporting a suture, and a needle slidably disposed within the first jaw, having a hook on a side for releasably capturing a portion of a suture, is provided. The first jaw defines a channel for receiving the needle and a ramp for deflecting the needle transversely of the shaft when advanced to an extended position. | 0 |
FIELD OF THE INVENTION
The present invention relates to a robotic gripping apparatus.
BACKGROUND OF THE INVENTION
Industrial robots often employ an articulated mobile structure, commonly referred to as an arm, with mobility approximating that of a human arm. Such a robotic arm is equipped with a so-called end effector to enable the robot to perform its assigned task.
In some applications, the end-effector performs a grasping or gripping function. One class of gripping end-effectors uses a set of individual prehensile mechanical fingers (typically two or more) which curl around an object, tightening around it in order to grip the object. This action closely mimics the grasping action of the human hand.
A mechanically simpler gripping action can be obtained by employing an attractive force, such as a magnetic or electric field or fluid suction. The gripper is placed against the object to be grasped and the attractive force is energized (e.g., the magnetic field or suction force is turned on). The object is then grasped for subsequent manipulation. When the robot is finished with the object, the attractive force is turned off, and the object is released.
However, some objects to be grasped are bulky and/or offer no obvious flat space against which to exert an attractive force. Examples include paint brushes and many surgical instruments. If, for example, a conventional electromagnet is used to grip a metal surgical instrument, the pole piece of the electromagnet may rest against a high spot or sharp surface or other irregular surface on the instrument. When the electromagnetic field is energized, the resulting grip may be less than satisfactory and the object may dangle, twist, or even be dropped.
SUMMARY OF THE INVENTION
In order to solve the problem of gripping objects that are not well-suited to being held using an attractive force, an improved gripping end-effector is proposed which is able to achieve a significantly more secure grip on bulky or oddly or irregularly shaped objects using an attractive force supplied at the end of each of a plurality of elongate members.
According to the present invention, a robotic gripping apparatus is provided which comprises a plurality of elongate members which independently adjust to the shape of an object to be gripped and are each capable of exerting an attractive force on the object.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention, together with further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings, wherein like reference numerals identify like elements, and wherein:
FIG. 1 shows a perspective cross section of a basic structure of a prior art pin and plate structure interacting with an object.
FIG. 2 shows a perspective cross section of an apparatus of the present invention and a pin locking mechanism of the present invention in an unlocked configuration.
FIG. 3 shows a perspective cross section of an apparatus of the present invention and a pin locking mechanism of the present invention in a locked configuration.
FIG. 4 shows a release mechanism of the present invention.
FIG. 5A shows an electromagnetic pin usable in the present invention.
FIG. 5B shows several permanent magnet pins usable in the present invention.
FIG. 5C shows a fluid suction pin usable in the present invention.
FIG. 5D shows a van der Waals force pin usable in the present invention.
FIG. 6A shows a fluid piston usable in the present invention for forcing a pin in either of two directions.
FIG. 6B shows a solenoid usable in the present invention for forcing a pin in either of two directions.
FIG. 6C shows a spring usable in the present invention for forcing a pin to a neutral position thereof.
FIG. 7 shows a cross section of a rounded tip of a pin usable in the present invention.
FIGS. 8A , 8 B, 8 C and 8 D show cross sections of an alternative locking mechanism according to the present invention.
FIGS. 9A and 9B show cross sections of another alternative locking mechanism according to the present invention.
FIG. 10 shows a cross section of a curved structure of a gripper device according to the present invention.
FIG. 11 shows a control unit usable with the present invention.
DETAILED DESCRIPTION
The elongate members of the present invention may be better understood by comparison with the action of a known children's toy called a PINPRESSIONS® 1000, a representation thereof being shown in FIG. 1 . This known device comprises an array of several hundred metal pins 1020 oriented vertically and parallel to each other. (For clarity of understanding, only a few of the pins 1020 are shown.) The pins 1020 are constrained to move parallel to each other by two parallel plates 1010 , both of which are perpendicular to the plurality of pins. The plates 1010 are spaced about one inch apart with each plate 1010 having matching sets of holes 1019 of slightly larger diameter than the pins 1020 . The fit between the pins 1020 and the holes 1019 allows the pins 1020 to slide freely in a direction perpendicular to the plates 1010 . A collar 1022 at the top of each pin 1020 prevents the pins 1020 from falling out of the toy 1000 in one direction, while a cover plate 1012 fastened to the two parallel plates 1010 by fastening structures 1015 prevents the pins from falling out of the toy 1000 in the opposite direction. In use, the toy 1000 is placed down onto an object 1050 and the pins 1020 adjust themselves in the vertical direction under the force of gravity to produce a relief image of the object 1050 .
According to the present invention, the end-effector 100 as shown in FIGS. 2 and 3 comprises a plurality of parallel, independently sliding or adjustable elongate members, hereinafter pins 120 . (For clarity of understanding, only a few of the pins 120 are shown.) Each pin 120 is movable or adjustable in an axial direction independent of the movement or adjustment of the other pins 120 in the axial direction and each pin 120 is also individually capable of exerting an attractive force on an object 50 . Various mechanisms to enable each pin 120 to exert such an attractive force may be applied, either the same mechanism for all pins in an end-effector 100 or different mechanisms for different pins in the end-effector 100 . For example, each pin 120 might comprise an electromagnet 120 a as in a first embodiment shown in FIG. 5A , a permanent magnet 120 b 1 , 120 b 2 as in a second embodiment shown in FIG. 5B , a tube 120 c through which a fluid pressure suction may be exerted as in a third embodiment shown in FIG. 5C , or a pad 120 d with microscopic hairs 125 d for increasing the surface area over which a van der Waals force acts as in a fourth embodiment shown in FIG. 5D .
In the embodiment shown in FIG. 5A , is provided by a wire 125 a wound around the electromagnet 120 a . In the embodiment shown in FIG. 5C , to enable exertion of the fluid pressure suction, a suction source 127 c is coupled to an interior 125 c of the tube 120 c via a connecting conduit 126 c.
In the embodiment shown in FIGS. 2 and 3 , there are three constraining plates 110 ; however, a single plate would be practicable in combination with pins 120 equipped with permanently attractive ends and a release plate 111 or in combination with pins 120 equipped with an attractive force which could be turned off. A locking mechanism utilizing the relative position of two or more constraining plates 110 would not be practicable with a single constraining plate. The number of constraining plates may therefore vary in different embodiments of the invention.
The constraining plates 110 each have a plurality of holes 119 through which the pins 120 are freely slidable, when the constraining plates 110 are not in a locking position described below. The pins 120 are prevented from falling through the constraining plates 110 by a collar 121 on each pin that is larger than the corresponding hole 119 in each plate 110 . Another form or construction may be provided, either in connection with the pins 120 and/or one or more of the constraining plates 110 , to maintain the pins 120 in the holes 119 in the constraining plate 110 .
The gripping process of the present invention comprises several operations.
First, conforming is performed, i.e., the end-effector 100 is conformed to the shape of the object 50 . Specifically, the pins 120 are pressed against the surface 51 of object 50 and they slide relative to constraining plates 110 to conform to the shape of the object 50 . Each pin 120 is equipped with a positioning member 131 (only one is shown for clarity of understanding) attached to an inside surface 106 of the main body 102 . As shown in FIGS. 6A , 6 B and 6 C, the positioning member 131 may comprise at least one of a spring 131 c , a solenoid 131 b , or a fluid-actuated piston 131 a for forcing each pin 120 in an outward normal direction of the constraining plates 110 . When the pins 120 are forced into contact with the surface 51 of the object 50 to be gripped by the end-effector 100 , the pins 120 conform to the shape of the object 50 because either the end-effector 100 is held stationary while the pins 120 are forced outwardly therefrom, or the object 50 is stationary while the end-effector 100 is moved closer to the object 50 or the object 50 is moved closer to the end-effector 100 . The pins 120 are constrained to move parallel to each other, i.e., in an axial direction of each pin 120 , by constraining plates 110 . A control unit 160 modulates or controls a force applied by the solenoid 131 b or the fluid piston 131 a , when present, on the pins 120 according to the nature of the object 50 .
Next, locking is performed. The pins 120 are locked in the positions obtained during the above-described conforming step by moving one or both of the constraining plates 110 relative to each other so that the pins 120 are locked in positions relative to the constraining plates 110 . Locking can be accomplished by translation and/or rotation of the constraining plates 110 by plate translating/rotating devices 112 . The plate translating/rotating devices 112 are attached to a main body 102 of the end-effector 100 by an attaching member 104 . If the fit between each pin 120 and its corresponding hole 119 in each constraining plate is a close one, only a small displacement by rotation and/or translation of one of the constraining plates 110 is necessary to exert a sufficient shear force on some or all of the pins 120 to lock the pins 120 in position. The required force could be provided by an actuator such as, for example, a solenoid, a fluid driven piston or other linear or arc actuator. Such an actuator would be preferably controlled by a control unit 160 shown in FIG. 11 (described later).
If only a single constraining plate 110 is used, locking does not occur.
Each plate translating/rotating device 112 must be capable of slightly translating or rotating at least one of the constraining plates 110 to provide sufficient force to lock the pins 120 in position. Each plate translating/rotating device 112 may comprise, for example, any number of linear or angular electromagnetic or fluid actuators.
After the pins 120 are locked in position, the attractive force is activated, preferably by the control unit 160 , in a gripping step (see FIG. 11 ). The object 50 can then be manipulated by the end-effector 100 during a manipulation step, and used for its intended purpose. Alternatively, the pins 120 can be locked in position after activating the attractive force.
Finally, the end-effector 100 may be operated to release the object 50 in a releasing step, e.g., after manipulation and/or use of the object 50 . One method of releasing the object 50 is to simultaneously de-energize the attractive force and release the locking mechanism. Alternatively, the pins 120 can be unlocked before the attractive force is deactivated or vice versa. After the object 50 is released, each pin 120 is returned to a neutral position by the positioning member 131 to the position it had before beginning the conforming step.
In some instances, it is advantageous to shape tips or ends 129 of the pins 120 with a shallow convex radius (see, for example, FIG. 7 ) or crown portion on the end rather than a flat end. This will enable the pins 120 to slide more easily over the surface of the object 50 (especially an irregularly shaped object 50 ) during conforming and release operations and will make them less prone to leaving scratch marks on the surface 51 of the object 50 .
In the embodiments of the present invention which utilize a permanent attractive force, the attractive force is permanently active and is provided by, for example, permanent magnets 125 b 1 and 125 b 2 located at the end 129 of each pin 120 . Conforming and locking are similar to those operations in the other embodiments, except that conforming occurs at the same time as gripping. Unlocking is also the same as in the other embodiments. Releasing the object 50 from pins 120 equipped with a permanently active attractive force requires retracting the ends 129 of the pins 120 into an interior 108 of the main body 102 of the gripper 100 or at least far enough apart from the object 50 so that the end 129 of enough of the pins 120 are prevented from being in contact with the object 50 so that the object 50 will not be held by the end-effector 100 .
In the case of permanent magnet equipped pins (see FIG. 5B ), the use of a holder 126 b 1 and 126 b 2 for a magnetic slug 125 b 1 and 125 b 2 is preferred because the slug itself may be difficult to machine. Each slug 125 b 1 and 125 b 2 has a North and South magnetic pole. The design as shown in FIG. 5B uses an array of slugs 125 b 1 and 125 b 2 with pole polarities alternating North and South. Such alternation of polarities is preferred because it results in little or no tendency to magnetize a metallic object after repeated grip and release cycles.
One configuration of the present invention, shown in FIG. 2 (see also FIG. 6C ), uses compression springs 131 c to drive the pins in an outward normal direction of the main body 102 of the end-effector 100 . A collar 121 on an interior end of each pin 120 interacts with a constraining plate 110 that can be moved by the plate translating/rotating device 112 to force all of the pins 120 entirely inside the main body 102 of the end-effector 100 so as to disconnect the pins 120 from the surface 51 of the object 50 .
An alternate configuration uses the pin positioning member 131 to retract the pins 120 . However, using a release plate 111 in combination with the pin collar 121 (see FIG. 4 ) to retract the pins 120 is preferable when the permanent attractive force being supplied is very large.
The gripping process of the permanent magnet equipped embodiments of the present invention is identical to the gripping process of other embodiments, except that the conforming and gripping steps occur at the same time. Locking of the pins should always follows conforming and gripping in permanent magnet equipped embodiments. Furthermore, release of the object 50 can only be adequately achieved by drawing the pins 120 entirely inside the main body 102 of the end-effector 100 .
FIG. 10 shows an alternate embodiment in which pins 220 are not parallel to each other and constraining plates 210 and 211 are curved. The pins 220 in this embodiment of the present invention are preferably locked by the locking mechanism shown in FIGS. 8A , 8 B, 8 C and 8 D (described below), due to the curved shape of the constraining plates 210 and 211 . This embodiment of the present invention is compatible with both permanent and temporary attractive forces. It is particularly suited to very oddly shaped objects 250 ( FIG. 10 ) with specific holding requirements. As in the previously described embodiments, the pins 220 in this embodiment are equipped with both positioning members 231 and collars 221 . A main body, control unit, and other parts of this embodiment are not shown in FIG. 10 for the sake of simplicity. All of the above-described pin and positioning mechanism designs are applicable to this embodiment.
As shown in FIGS. 8A , 8 B, 8 C and 8 D, the pair of constraining plates 110 may be movable closer together to compress a fluid chamber 141 (or alternatively a foam) between the two constraining plates 110 to cause flexible walls 142 of the chamber 141 to come into contact with the pins 120 . Alternatively, the fluid pressure in the chamber 141 may be increased by action of a pump or piston 146 connected to the chamber 141 which deforms the flexible walls 142 and cause them to come into contact with the sides of the pins 120 . The pump or piston 146 or the motion of the constraining plates 110 is preferably controlled by the control unit 160 . It is preferable that the flexible walls 142 be made of a high friction material such as rubber or coated with a high friction material 147 . Only a few pins are shown and the main body and other parts are omitted from FIGS. 8A , 8 B, 8 C and 8 D for the sake of clarity. The locking mechanism of FIGS. 8A , 8 B, 8 C, and 8 D can be used with all embodiments of the present invention.
As shown in FIGS. 9A and 9B , an electromagnet 143 may be used to drive the pins 120 against an inside surface 144 of holes 119 in one of the constraining plate 110 . In this embodiment, a single constraining plate may be used if it has sufficient thickness to maintain the pins 120 in positions substantially parallel to the inside surface 144 of the holes 119 . In this case, it is preferable that the inside surface 144 of the hole and the side surface 145 of the pin 120 are either roughened or grooved to enhance the effectiveness of the locking force provided by the electromagnet 143 . A fluid flowing parallel to and between the plates 110 may provide the locking force. Only a single pin is shown in FIGS. 9A and 9B and the main body, the other pins 120 , and other parts are omitted from FIGS. 9A and 9B for the sake of clarity.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. | A robotic gripping apparatus includes one or more constraining plates each having a plurality of holes formed therethrough and a plurality of elongate members. The elongate members are independently movable relative to one another. Each elongate member extends through a respective hole or set of aligning holes in the constraining plate(s). A distal end portion of one or more of the elongate members is capable of exerting a force for drawing an object against the distal end portion to thereby hold or grip the object. | 8 |
FIELD OF THE INVENTION
The present invention relates to the completion of wells and, more particularly, it relates to a method of drilling a productive bed.
BACKGROUND OF THE INVENTION
The completion of wells involves a wide range of technological operations including the tapping of productive beds, formation testing in an open shaft, well lining and cementing, as well as the tapping of beds by perforation with subsequent outfitting of the well with undeground and ground equipment and bringing in of the well. The well productivity and duration of its exploitation depend upon the quality of execution of the afore-listed technological operations.
The principal objective in the completion of well is maintaining the natural filtration characteristic of the reservoir bed. A deterioration of the reservoir properties of the bed is caused by the penetration of filtrate and the solid phase of flushing fluid into the well face zone, which leads to the various irreversible processes in the bed. In so doing, there taken place the blocking of interstitial space with water-oil emulsion, the clogging of pore canals with the solid phase of flushing fluid, the plugging of interstitial space with swelling clay and products of chemical interaction of the flushing fluid filtrate with reservoir fluids and rock, reduction of the pore size due to rock deformation upon tapping, etc.
At present, the work related to the completion of wells is directed mainly towards:
setting up conditions for efficient execution of operations while tapping a bed for maintaining reservoir properties of the latter; and
intensifying the influx of fluid to a well by chemical, thermochemical, hydraulic and other means.
Investigations have shown that there are up to 3,000 outlet openings of pore canals per square inch of common sandstone (cf., Maly George P. Minimizing Formation Damage. Proper Fluid Selection Helps Avoid Damage, Oil and Gas J., 1976, 22/III, No. 74, No. 12, pp. 68-70). Said openings differ in shape and size and are readily contaminated with solid particles of inorganic and organic substances, and with polymers. Even if the majority of such canal openings in the shaft zone of the bed are contaminated, the well is still of some commercial value; however, its rating is extremely low and the flow rate decreases rapidly.
If the shaft zone of the bed is contaminated through a considerable depth, the initial permeability of clogged rock cannot be restored. However, in the case of contamination of but a part of the shaft zone of the bed (natural filter), the rock permeability is restored following an appropriate treatment of the well face zone.
Four main types of bed contamination are distinguished, namely:
1. The clogging of pore canals in the rock with solid particles penetrating the bed from the flushing fluid upon drilling, perforation and maintenance work in the well.
2. The contamination of the bed due to a reaction between clays contained in the bed with fresh water penetrating the bed serves a reason for the swelling or dispersion of the clays.
3. The contamination of the bed associated with an increased water saturation of rocks near the well shaft, due to fluid filtration into the bed upon drilling.
4. The formation of pockets in the bed and evacuation of loose rock from the well.
It has been found that one of the reasons for reservoir contamination is the formation of a zone of increased water saturation in the reservoir, the penetration of the interstitial space of the bed by clay particles from flushing fluid, the clogging by said particles of pore canals and hydration of clays, which results in the swelling or dispersion of particles in pore canals, injection of contaminated water into the bed and evacuation of sand upon destruction of poorly cemented rocks (cf., Izucheniye haraktera zagriazneniya plasta s pomoschiyu kernov i kernovyh analizov--Studying the Nature of Bed Contamination with the Aid of Cores and Core Analyses. Express Information, series on Petroleum and Gas Mining, No. 41, VINITI, Moscow, 1977).
In order to preclude the formation of a zone of increased water saturation in the shaft portion of the bed or to reduce the size of such zone, while tapping the bed use is made of inert flushing fluids, oil-based solutions, compressed gas, water. However, the substitution of, for example, water for flushing fluid in the course of bringing in of wells accomplishes nothing, inasmuch as the bed has already been clogged and no additional hydrodynamic or thermochemical effect will restore its initial rating, since productive reservoirs are made up mainly of hydrophilic materials and, upon interaction with clay particles activated with adsorptive-active reagents, exhibit stable assimilation in the pores (clogging).
DESCRIPTION OF THE PRIOR ART
There are also known methods of drilling productive beds, comprising the tapping of the bed roof using flushing fluid, with subsequent replacement of the latter with a flushing fluid featuring altered physical-chemical properties (cf., K. Ghetlin, Bureniye i zakanchivaniye skvazhin--Drilling and Completion of Wells, Gostoptehizdat, Moscow, 1963, pp. 362-363).
Said prior art methods are characterized, depending on the rock being penetrated, by varying the properties of flushing fluid, reducing filtration, replacing the clay solution with water, oil or some other solution compatible with the given rock. However, all of said prior art methods fail to preclude reduction-oxidation reactions between the flushing fluid and bed rock which, in turn, leads to the clogging (colmatage) of the bed. In addition, the replacement of basic flushing fluid used in the drilling of common beds with a special flushing fluid of altered physical-chemical characteristics requires for additional expenses caused by the preparation of the latter fluid and by the execution of technological steps associated with the replacement of flushing fluid.
SUMMARY OF THE INVENTION
The present invention is aimed at solving the problem of developing a method of drilling a productive bed, by replacing the flushing fluid with a fluid of altered physical-chemical properties that would provide, owing to said variation of flushing fluid properties, for a considerable reduction of the degree of colmatage of the productive bed and for the preservation of its natural permeability, thereby increasing the rating of the bed while simultaneously reducing the consumption of labor and materials.
The problem of the invention is solved by the use of a method of drilling a productive bed, comprising tapping of the bed roof using a starting flushing fluid, and subsequent replacement of the latter with a flushing fluid of altered physical-chemical properties. According to the present invention, the value of redox potential of the bed-forming rock is determined at the moment of tapping the bed roof and the flushing fluid of altered physical-chemical properties is a fluid having a redox potential value and sign equal to those of the productive bed rock.
The tapping of a bed using a fluid featuring physical-chemical properties close to those of the rocks making up the protective bed, i.e., the properties which rule out mutual aggression of rock and flushing fluid, in particular, the equality of redox potentials eliminates ion-exchange processes between the minerals making up the rock and flushing fluid, which results in a sharp reduction of the flushing fluid filtrate penetration into the bed and of the colmatage power of the flushing fluid, as well as in the preservation of natural permeability of the productive bed.
It is expedient that the value and sign of the redox potential of the productive bed rock at the moment of tapping said bed be determined from their deviation from the value and sign of the redox potential of the starting flushing fluid.
This helps improve the information on the productive bed, accelerate the process of determining the redox potential of the productive bed rock and reduce the expenses by eliminating additional steps required for the analysis of slurry of rocks being drilled.
It is preferable that the variation of the value and sign of the redox potential of the flushing fluid be effected by treating the flushing fluid in one of the electrode zones of a diaphragm cell. This provides a possibility of varying the physical-chemical properties of the flushing fluid in a wide range while maintaining its basic working parameters and quality, with a simultaneous reduction of chemical reagent consumption by fully eliminating the need to use such reagents.
It is desirable that the variation of the value and sign of the redox potential of the flushing fluid be effected in the range of from -1.6 V to +1.8 V, depending on the mineral composition of the productive bed rocks. This provides a possibility of carrying out the process of drilling the productive bed made up of rocks of diverse mineral composition without the need for the colmatage of said rocks.
DETAILED DESCRIPTION OF THE INVENTION
As is known, all reservoirs making up productive beds feature a diffusion-adsorption activity. Said activity consists essentially in that, when solutions of different concentrations are separated from each other by a porous partition, there occurs the diffusion of ions from a more concentrated solution to a less concentrated one.
The diffusion phenomenon is due to reduction-oxidation reactions occurring in complex heterogeneous systems such as fluid-saturated productive beds and the flushing fluid coming in contact with the bed and fluids thereof in the course of tapping the beds.
When tapping a productive bed, the flushing fluid affected by pressure higher than the reservoir pressure penetrates the pores of the well face zone to leave clay particles in said pores. In the zone of flushing fluid contact with the rock being drilled, ion-exchange processes occur leadng to reduction-oxidation reactions. The redox potential serves the measure of intensity of the reduction-oxidation processes. The value of redox potential depends on the ratio of concentrations of the oxidation and reduction forms of ions making up the system under consideration.
Under stationary, i.e., very slowly varying in time, conditions of energy exchange with neutral environment, the redox potential of flushing fluid usually takes an equilibrium value corresponding to the ratio of oxidizer activity to reducer activity equal to 0.5. An important index of the system chemical activity such as pH also takes under these conditions a neutral value equal to 7.
Any deviation of said two characteristics from the equilibrium position means that the system is energetically unstable and that reduction-oxidation reactions may occur in said system both upon contact with the environment (rock of the well walls, fluids supplied to the solution in the course of drilling) and upon contact between particles and phases of the system proper.
As a result of difference between the redox potential values of the flushing fluid and rock, the flushing fluid filtrate is supplied to the bed, clogs the interstitial space of the reservoir (rock) and intensifies reduction-oxidation reactions between the flushing fluid filtrate and the system of filtrate-saturated bed.
For precluding the afore-described phenomena, in particular, for neutralizing the reduction-oxidation reactions between the flushing fluid and productive bed rock, use can be made of the herein disclosed invention. At the moment of tapping the productive bed, the value and sign of the redox potential of the rocks making up the productive bed are determined. To this end, the redox potentials are measured of the flushing fluid entering the well and of the flushing fluid leaving said well, which redox potentials will have different values because of chemical reactions occurring in the zone of contact of the flushing fluid with the productive bed rock. Then, the value of the redox potential of the productive bed rock is found, for example, from the difference between the values of redox potential of the incoming and outgoing fluid. Said difference between the redox potential values of the incoming and outgoing fluids provides information on the lithological composition of the rock being drilled. Using special monographic charts, the resulting difference is related to some or the other rock composition. Given the rock composition, one can find from the tables the normal redox potential of the rock being drilled.
The redox potential is measured by conventional means, for example, with the aid of a calomel electrode by Kryuikov (cf., A. I. Boldyrev, Fizicheskaiya i kolloidnaya himiya--Physical and Colloid Chemistry, Vyschaiya Shkola Publishers, Moscow, 1974, p. 319).
Thereupon, the starting flushing fluid circulating in the well is replaced with another flushing fluid whose physical-chemical properties differ from those of the starting fluid; but which, however, resemble closely the physical-chemical properties of the productive bed rock. In other words, a fluid is injected into the well having a redox potential equal in sign and value to that of the productive bed rock. The equality of redox potential values and the uniformity of their signs (positive or negative) preclude the occurrence of reduction-oxidation reactions between the bed rock and flushing fluid which, in turn, serves to reduce the intensity of diffusion-adsorption over-flows of the flushing fluid filtrate to the bed and of the reservoir fluids to the flushing fluid.
Used as the flushing fluid having a redox potential equal to that of the rock is the same flushing fluid which was used throughout the well drilling process, the only exception being that, prior to tapping the productive bed, said fluid is pre-treated in the zone of one of the electrodes of the diaphragm cell until reaching a redox potential equal in sign and value to that of the productive bed rock.
The redox potential of the flushing fluid can be varied by adding various chemical reagents thereto; however, this results in an increased cost of the drilling process.
The flushing fluid is pre-treated in the diaphragm cell until reaching a redox potential value in the range of from -1.6 to +1.8 V. This range of the redox potential values covers the entire gamut of rocks making up productive beds.
Presented hereinbelow is a detailed description of the preferred embodiment of the method of the invention, with references to the accompanying drawing which illustrates diagrammatically the process of drilling a productive bed.
At the moment of tapping a productive bed A-B or, rather, the roof thereof at point A, the redox potential is measured of a flushing fluid entering a well 1 and of that leaving said well. Depending on the composition of rocks making up the productive bed, the redox potential of the flushing fluid will exhibit an increase or decrease. The redox potential is measured by means of a pickup 2 with a recorder 3. A calomel electrode is used as the pickup 2. First, the difference is found between the redox potential values of the incoming and outgoing flushing fluids. Based on preliminary nomographic charts, there is determined the lithological composition of the rock to which the obtained difference of redox potential values corresponds. Then, the normal redox potential value corresponding to the given rock composition is found from the tables. In this manner, the sign and value of the redox potential of the productive bed rock is found. After that, the flushing fluid leaving the well is directed to a diaphragm cell 4 provided with a d.c. source 5, where it is subjected to electric treatment.
If the redox potential of the rock of the productive bed being drilled has a positive sign, the flushing fluid is treated in a zone 6 of a positive electrode 7. In case the redox potential of the rock has a negative value, the flushing fluid is treated in a zone 8 of a negative electrode 9. The flushing fluid is subjected to electric treatment until its redox potential reaches the same value and sign as those of the redox potential of the productive bed rock.
The variations in the value of the redox potential over the productive bed thickness are assumed to be close to average for the given type of rock in the range of from -1.6 V to +1.8 V. For example, the fluctuations of the redox potential caused by the difference in the properties and chemical composition of like rocks saturated with a fluid of one type may range (in terms of power) from several (often) to tens of (seldom) millivolts. The fluctuations of the redox potential caused by transition from rocks of one type to rocks of another type having a different chemical composition range from tens to hundreds of millivolts, depending on the extent of their difference. In addition, said values provide the limits of reversible electrochemical reactions. A deviation of the redox potential value to either side by more than 0.2-0.5 V may lead to irreversible chemical reactions within the flushing fluid itself, which may cause the deterioration of the latter. Therefore, the treatment of the flushing fluid in the electrolyzer should be carried out within the afore-specified limits of the redox potential value.
The thus treated flushing fluid is injected in the well 1 while continuing the tapping of the productive bed A-B by a drilling tool 10. Inasmuch as the flushing fluid is chemically passive with respect to the bed rock, there occur no diffusion-adsorption overflows therebetween, the bed is not clogged and its rocks retain their natural permeability.
The present invention will help increase the bed rating by at least 40-50% owing to reduced colmatage and retained natural permeability, as well as reduce material and technical costs due to the possibility of using the same flushing fluid with an altered redox potential and of eliminating the need to use costly chemical reagents for treating the flushing fluid. Presented hereinbelow is a specific example illustrating the execution of the method according to the present invention.
EXAMPLE
3,735 Meters were drilled in the course of well drilling. Prior to tapping the productive bed roof located at the 3,740-m level (the cover thickness of the productive bed roof was found from the geological column based on exploration data), measurements were begun of the redox potential values of the starting flushing fluid delivered to the well and discharged therefrom. Down to the level of 3,500 m, the well was cased; below the casing string, the rocks made up of quartzy sandstone were drilled. The redox potential value of the incoming flushing fluid was -400 mV and the outgoing fluid --380 mV. At the moment of tapping the productive bed roof, the redox potential value of the outgoing fluid varied sharply up to -300 mV. The circulation was discontinued for a period of 15 minutes, after which it was resumed. At the well outlet, the redox potential value of the batch of flushing fluid in contact with the tapped productive bed for 15 minutes was -200 mV. According to the data obtained from earlier experiments, such a deviation of the redox potential value is characteristic of a sandy reservoir bed saturated with highly viscous oil having a high content of taryy substances. According to a scale of values of own normal redox potentials of rocks (cf., A. I. Boldyrev, Fizicheskaiya i kolloidnaiya himiya--Physical and Colloid Chemistry, Vyschaiya Shkola Publishers, Moscow, 1974), the redox potential of an oilsaturated sand bed is +200 mV.
Thereafter, the starting flushing fluid was supplied to the zone of the positive electrode of a diaphragm cell wherein its redox potential value was brought to +200 mV as a result of unipolar treatment, thereby changing the physical-chemical properties of said fluid. Further circulation of the flushing fluid, as the productive horizon was drilled on, was effected using the flushing fluid having the redox potential value of +200 mV. Following the completion of the productive bed, the well was flushed with the same fluid. Inasmuch as the flushing was effected under conditions of some counter-pressure on the bed, part of said fluid entered the face zone of the bed, however, no physical-chemical ion-exchange reactions occurred between the flushing fluid, bed rock and reservoir fluids, since all these were chemically neutral with respect to each other. After that, the cementation of the extracting column was effected. Upon the injection of cement into the annulus, the plugging grout did not clog the face zone of the productive bed since the latter zone contained a flushing fluid with altered physical-chemical parameters, said fluid serving to preclude the grout penetration into the bed.
The natural permeability of oil sandstone was found from a core sample to be 240 md. After injecting in the well the flushing fluid of altered redox potential, according to the invention, the rock permeability was 230 md. When tapping productive beds by conventional methods, the permeability decreased to 160 md due to the colmatage of the face zone. After the casing perforation in the productive bed zone and generation of the influx of oil by generating depression on the bed, the well rating agreed with theoretical data calculated from natural permeability and amounted to 450 m 3 per day while the rating of an analogous well drilled by conventional methods amounted to 270 m 3 per day. Thus, the method of the present invention provides for a 40% increase of the well rating as compared with prior art methods.
Industrial Applicability
The herein disclosed method can find extensive application in petroleum and gas mining and in geological exploration. | The present invention relates to the completion of wells and, more particularly, it relates to a method of drilling a productive bed.
The herein disclosed method of drilling a productive bed comprises the tapping of the bed roof using a starting flushing fluid and the determination of the redox potential value at the moment of tapping the bed roof, and subsequent replacement of the starting flushing fluid with a fluid having redox potential value and sign equal to those of the productive bed rock. | 4 |
BACKGROUND
[0001] 1. Technical Field
[0002] The present disclosure is directed to a fabrication process of a structural component. More particularly, the present disclosure is related to a fabrication process for a structural component to be used with high strength structural applications. Even more particularly, the present disclosure relates to a fabrication process for a structural component that results in a component having a homogeneous nano/sub-micron grain structure.
[0003] 2. Description of the Related Art
[0004] High strength engineering components are known in the art. Plastic deformation has been used in the art to structurally alter and to enhance one or more physical properties of a work piece component for different metallic materials. One such known method entails using a die having a movable surface in a deformation channel of the die. The movable surface moves with a work piece material during a deformation process in the deformation channel. The billets have selected desired characteristics resulting from the deformation processing such as an improved strength and ductility. However, construction using such billets is expensive, due in part, because the billets or desired structural components can be formed only by using a very complex and cumbersome die structure. The complex die structure and components are expensive to use and make. They require additional expenses not only to form the die, but also to operate, and service the die for manufacturing a number of structural components or billets.
[0005] Moreover, such known dies have a detrimental operation and have die components that only minimize friction in one general direction or on the face of the work piece material. Such dies minimize friction in only a complementary location where a sliding die component moves. Such a reduction in friction may only provide a limited structural enhancement depending on the application. The friction on another side of the work piece material is relatively greater between the die component and the structural work piece component. This results in non-homogenous sized grains in the resulting structural component. This non-homogenous condition due to the increased friction on the one side relates to poor mechanical properties. This may lead to one or more unintended detriments depending on the structural application.
[0006] Thus, a need exists to develop a fabrication method which includes improved process steps that do not require an expensive die or die components to conduct the plastic deformation process. In addition, a need exists to develop a fabrication process that provides a homogenous sub-micron grain size across the cross section of the work piece component.
SUMMARY
[0007] According to a first aspect of the present disclosure, there is provided a method for processing a work piece having a front end, a back end, and a plurality of lateral sides. The method has the steps of providing a die having an entrance channel with a longitudinal axis and an exit channel. The entrance channel and the exit channel are connected to one another. The method has the step of placing the work piece in the entrance channel and disposing a first sacrificial material between the die and at least one lateral side of the work piece. The method also has the steps of extruding the first sacrificial material and the work piece material through the exit channel.
[0008] According to another aspect of the present disclosure, the method has the front end and the back end exposed and substantially free from contacting the first sacrificial material.
[0009] According to yet another aspect of the present disclosure, the method has all of the plurality of lateral sides in contact with the first sacrificial material.
[0010] According to still another aspect of the present disclosure, the method has first sacrificial material and the work piece with each being substantially orthogonal shaped members with a flat mating surface.
[0011] According to still yet another aspect of the present disclosure, the method has the work piece selected from the group consisting of nickel, a nickel alloy, a nickel base alloy, a nickel base alloy being strengthened by a precipitate, nickel base alloy being strengthened by a gamma prime precipitate or a nickel based super alloy, a co-base super alloy, an oxide dispersion strengthened alloy, a multi-layered combination of materials, an iron based alloy, and an aluminum based alloy, and titanium and titanium alloys.
[0012] According to another aspect of the present disclosure, the method has the first sacrificial material selected from the group consisting of carbon, graphite, aluminum, an aluminum alloy, copper, and a copper alloy.
[0013] According to still yet another aspect of the present disclosure, the method has sub-micron sized grains formed in the work piece. The grains are disposed in a substantially homogenous fashion throughout a cross section of the work piece.
[0014] According to yet another aspect of the present disclosure, the method has the first sacrificial material surrounding the work piece in a manner to reduce friction between the work piece during extrusion. The method also has the step of optionally repeating extrusion of the first sacrificial material and the work piece through the die.
[0015] According to another aspect of the present disclosure, the method has the first sacrificial material with substantially the same flow stress as the work piece.
[0016] According to another aspect of the present disclosure, the method has the first sacrificial material and the die have a first coefficient of friction at an interface therebetween. The first coefficient of friction is different relative to a second coefficient of friction being between a second interface between the die and the work piece.
[0017] According to another aspect of the present disclosure, the method has the sacrificial material and the work piece substantially filling the entrance channel.
[0018] According to another aspect of the present disclosure, the method has the first sacrificial material and the work piece substantially filling the exit channel.
[0019] According to another aspect of the present disclosure, the method has the first sacrificial material with a first vertical axis and the work piece having a second vertical axis. The first vertical axis and the second vertical axis form an angle. The angle is about zero.
[0020] According to another aspect of the present disclosure, there is provided a method for processing a work piece with a front end, a back end, and a plurality of lateral sides. The method has the step of providing a die with the die having an entrance channel and a longitudinal axis and an exit channel. The entrance channel and the exit channel are connected to one another, and the method also has the step of placing the work piece in the entrance channel with the step of disposing a first sacrificial material between the die and at least one lateral side of the work piece. The method further has the step of disposing a second sacrificial material between the die and at least one other lateral side of the work piece with the step of extruding the first sacrificial material, the second sacrificial material and the work piece through the die and through the exit channel.
[0021] According to another aspect of the present disclosure, the method has the first sacrificial material about the same size as the work piece.
[0022] According to another aspect of the present disclosure, the method has the second sacrificial material about the same size as the work piece.
[0023] According to still another aspect of the present disclosure, the method has the second sacrificial material and the first sacrificial material each with a flow stress. The flow stress is less than the flow stress of the work piece.
[0024] According to another aspect of the present disclosure, the method has the front end and the back end exposed and substantially free from contact with the first sacrificial material and the second sacrificial material.
[0025] According to another aspect of the present disclosure, the method has all of the lateral sides contacting either the first sacrificial material and the second sacrificial material.
[0026] According to another aspect of the present disclosure, the method has the step of imparting a clamping force perpendicular to the work piece to hold the work piece composite in the die.
[0027] According to another aspect of the present disclosure, the method further comprises the step of repeatedly extruding the first sacrificial material and the second sacrificial material with the work piece through the die.
[0028] According to another aspect of the present disclosure, there is provided an extrusion apparatus. The apparatus has a first “L” shaped die cavity forming an “L” shaped extrusion channel and a plurality of sacrificial materials in the extrusion channel. The apparatus also has the plurality of sacrificial materials contacting a first lateral side and a second lateral side of a work piece. The work piece also has a front side, and a rear side. The apparatus further has the plurality of sacrificial materials imparting a shear deformation on the first and the second lateral sides of the work piece material upon extrusion through the extrusion channel and the plurality of sacrificial materials leave the front side and the rear side exposed.
BRIEF DESCRIPTION OF THE FIGURES
[0029] Various embodiments will be described herein below with reference to the drawings wherein:
[0030] FIG. 1 is a flow chart of the fabrication process according to the present disclosure;
[0031] FIG. 2 is a schematic diagram of a die having a first extrusion channel and a second extrusion channel according to the present fabrication process;
[0032] FIG. 3 is a schematic diagram of a work piece material placed between a first sacrificial material and a second sacrificial material;
[0033] FIG. 4 is another schematic view of the die of FIG. 2 with the work piece material of FIG. 3 in the die and between the first sacrificial material and the second sacrificial material;
[0034] FIG. 5 is a lateral side view of a first sacrificial material made from aluminum and the work piece material made from nickel after being extruded;
[0035] FIG. 6 is a view of the nano/sub-micron grains of the work piece material at 50 nm;
[0036] FIG. 7 is another view of the nano/sub-micron grains of the work piece material at 50 nm;
[0037] FIG. 8 is a view of the nano/sub-micron grains of the work piece material at 110 nm; and
[0038] FIG. 9 is another view of the nano/sub-micron grains of the work piece material at about 122 nm.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0039] Reference should be made to the drawings where like reference numerals refer to similar elements throughout the various figures. The fabrication process of the present disclosure controls a microstructure of a work piece material resulting from a deformation of the work piece material. The fabrication process uses a first sacrificial material and, in some embodiments, a second sacrificial material, to reduce friction between a die and the work piece, and thus form a homogenous nano/sub micron sized grains in the work piece material or work piece.
[0040] Referring now to FIG. 1 , there is shown a process flow chart of the fabrication method 10 of the present disclosure. The method 10 has the first step 12 of arranging the die. Thereafter, the method proceeds to step 14 . At step 14 , the method has the step of providing a work piece in the die. The work piece is defined as the material that will undergo the plastic deformation in order to result in a controlled microstructure. Thereafter, the method proceeds to step 16 . At step 16 , a first sacrificial material is prepared. The first sacrificial material has dimensions that are complementary to the dimensions of the work piece material. The first sacrificial material moves with the work piece material during a shear process and thus reduces friction and contact between the work piece material and the die. Thereafter, the method proceeds to step 18 .
[0041] At step 18 , for those embodiments employing a second sacrificial material, the second sacrificial material is prepared. The second sacrificial material has dimensions that are also complementary to the dimensions of the work piece material and the first sacrificial material. Likewise, the second sacrificial material moves with the work piece material during the shear process and thus reduces friction between the work piece material and the die. The second sacrificial material is placed on an opposite side of the work piece material so that the first sacrificial material and the second sacrificial material are opposite one another with the work piece material between both the first sacrificial material and the second sacrificial material to form a composite or sandwich. Thereafter, the method proceeds to step 20 .
[0042] At step 20 , the first sacrificial material and the second sacrificial material (if used) opposite the first sacrificial material with the work piece material disposed therebetween are all placed in an entrance channel of the die. Thereafter, the method proceeds to step 22 . At step 22 , a suitable force is applied to the combined first sacrificial material/work piece material and second sacrificial material to extrude the composite billet through the die. Thereafter, the method proceeds to step 24 . At step 24 , the extrusion step may be optionally repeated. One should appreciate the method may advantageously be conducted with a single pass through the die, and the method is not limited to any multiple passes through the die. Notwithstanding, the extrusion step may be optionally repeated with a 180 degree rotation of the combined first sacrificial material/work piece material and second sacrificial material. Thereafter, the method proceeds to step 26 . At step 26 , the resulting work piece material having homogenous and uniform sub-micron grains is removed from the first and the second sacrificial materials and is ready for a final finishing operation to make the work piece material ready for the relevant high strength application. One such application may be an airfoil or a turbine blade. Various finished product configurations are possible.
[0043] Referring to FIG. 2 , there is shown a schematic diagram of one embodiment of the presently disclosed system 28 with a die 30 for forming a number of sub-micron sized grains in the work piece material. “Submicron” sized or “nano sized” grains means that the resulting deformation process forms grains in a range of size that includes below a millionth of a meter. This process is called equal channel angular extrusion. By decreasing a grain size of the work piece material, an increase in strength of the material will result. A microstructure with nano or sub-micron sized grains results from the deformation processing. The nano sized grains and the homogeneous arrangement of the nano sized grains enhance one or more mechanical properties of the work piece material resulting from the deformation. The resulting work piece material having increased strength can then be used in any number of applications, such a turbine application, a turbine blade application, a compressor application, a compressor blade application, a nuclear application, a combustor application, a fan compressor application, an airfoil application, an air inlet application, or an air or gas exhaust application, a transportation or aerospace application, a rotary rotational movement application, or any other number of applications that require a structural component with a controlled microstructure and high strength or improved ductility.
[0044] The die 30 has a first die component 32 and a second die component 34 with a die cavity 36 disposed between the first die component 32 and the second die component 34 . The first die component 32 and the second die component 34 each are made from a tool steel, or another suitable high strength suitable material, or alloy. The die 30 is made from a suitable material that will maintain integrity during an extrusion process. The first die component 32 and the second die component 34 are form substantially an “L” shaped die cavity 36 .
[0045] The die 30 also has other assemblies in order to clamp and connect the first die component 32 to the second die component 34 with another material therein disposed therebetween. The die 30 further has an entrance channel 38 and an opposite exit channel 40 . Each of the entrance channel 38 and the exit channel 40 are generally orthogonal shaped and communicate with the die cavity 36 . In another embodiment, the entrance channel 38 and the exit channel 40 may have different shapes or configurations relative to one another such as a circular configuration.
[0046] Referring now to FIG. 3 , the system 28 further has a first sacrificial material 42 and a second sacrificial material 44 . The first and the second sacrificial materials 42 , 44 are generally orthogonal or rectangular members each made of the same or a different material. In this embodiment, the first and the second sacrificial materials 42 , 44 each have a substantially flat outer surface. The term “sacrificial” means that the material of this element of the present disclosure is intended not to form any of the finished final structurally enhanced products, and is intended to be discarded.
[0047] The system 28 further has a work piece 46 . The work piece 46 is a member in which the nano/sub micron sized grains are to be formed, and that is to be used as the high strength component as discussed previously. The work piece 46 is generally an orthogonal shaped or a rectangular member. In another embodiment, the work piece 46 may have any desired shape as long as the sacrificial materials 42 , 44 have the complementary shape to accommodate the work piece 46 . In this embodiment, the work piece 46 has a substantially flat outer surface. The work piece 46 may be nickel, a nickel alloy, a nickel base alloy, a nickel base alloy being strengthened by a precipitate, nickel base alloy being strengthened by a gamma prime precipitate or a nickel based super alloy, a co-base super alloy, an oxide dispersion strengthened alloy, a multi-layered combination of materials or a composite, an iron based alloy, and an aluminum based alloy, and titanium and titanium alloys or a suitable combination of materials. The sacrificial materials have a flow stress less than or equal to the flow stress of the work piece 46 . The flow stress is the stress required to cause a plastic deformation in metallic materials. If the flow stress of the sacrificial materials 42 , 44 is low, the overall applied force required to deform the system is lowered. This places less demanding requirements on the press used for extrusion. Pure aluminum, as one non-limiting exemplary example, has a range of flow stress from 2 to 70 Megapascals (hereinafter “MPa”) depending on temperature, strain rate and strain. Work pieces 46 will usually be relatively much higher or as much as 1,000 Mpa.
[0048] The first sacrificial material 42 and the second sacrificial material 44 are both disposed to surround the work piece 46 so as to move with the work piece 46 during an extrusion process through the die cavity 36 of FIG. 2 . The first sacrificial material 42 is disposed on a first lateral side 48 of the work piece 46 and the second sacrificial material 44 is disposed on an opposite or second lateral side 50 . The first sacrificial material 42 is disposed substantially parallel to the work piece 46 on the first lateral side 48 so an angle therebetween is about zero. The second sacrificial material 44 is also likewise disposed substantially parallel to the work piece 46 on the opposite side 50 of the first sacrificial material 42 so an angle therebetween is about zero. Each of the first sacrificial material 42 and the second sacrificial material 44 has a similar and complementary configuration relative to one another. Additionally, each, in another embodiment, may have the same material having the same size and shape. In one embodiment, each is a substantially rectangular shaped member. The first sacrificial material 42 may be aluminum, an aluminum alloy, a copper, a copper alloy, a combination thereof, or any material with a relatively low flow stress. Likewise the second sacrificial material 44 may be the same or different than the first sacrificial material 42 and may be aluminum, an aluminum alloy, a copper, a copper alloy, a combination thereof, or any material with a low flow stress. The first and the second sacrificial materials 42 , 44 instead each have flow properties or characteristics that allow the first and the second sacrificial materials 42 , 44 to flow with the work piece 46 in a manner such that the work piece 46 experiences less friction between the work piece 46 and the die cavity 36 during extrusion. The first and the second sacrificial materials 42 , 44 are intended to prevent the work piece 46 from contacting some of the inner surfaces of the die 30 . This prevents friction forces arising from any contact with the die 30 thereby potentially causing a non-homogenous grain size in the work piece 46 during the severe plastic deformation in the die 30 during extrusion. The first and the second sacrificial materials 42 , 44 with low flow stress, also serve the purpose of reducing overall loads to effect extrusion. Moreover, the first and the second sacrificial materials 42 , 44 also enable extrusion of thin sheets of work pieces 46 .
[0049] Referring now to FIG. 3 , there is shown a perspective view of the first sacrificial material 42 , and the second sacrificial material 44 with the work piece 46 placed therebetween. As shown, each of the first sacrificial material 42 and the second sacrificial material 44 with the work piece 46 forms an unconnected composite structure collectively indicated by reference numeral 52 . Referring now to FIG. 4 , the composite 52 or sandwich is placed in the die 30 . One aspect of the present disclosure is that the first sacrificial material 42 has a first vertical axis 54 and the work piece 46 also has a second vertical axis 56 . The angle between the first vertical axis 54 and the second vertical 56 axis is zero when the first sacrificial material 42 is placed adjacent to the work piece 46 as shown in FIG. 3 .
[0050] Likewise, the second sacrificial material 44 has a third vertical axis 58 . The angle between the third vertical axis 58 and the second vertical axis 56 of the work piece 46 is also zero when the second sacrificial material 44 is placed adjacent to the work piece 46 as shown in FIG. 3 . A suitable lubricant is then applied to one or more inner surfaces of the die cavity 36 as shown in FIG. 4 . Various lubricants or lubricating configurations are possible and are within the scope of the present disclosure. The composite 52 then undergoes a severe plastic deformation by an Equal Channel Angular Extrusion using the die 30 , where the composite 52 is extruded from the entrance channel 38 through the exit channel 40 by Force F as illustrated by the reference arrow. The Equal Channel Angular Extrusion operation results in the work piece 46 during the extrusion undergoing an intense shear deformation by passage through the die cavity 36 . This leads to a refinement of the microstructure of the work piece 46 of the composite 52 or sandwich. The extrusion process can be performed using a suitable hydraulic pressing apparatus introduced into the entrance channel 36 of the die 30 . Various extrusion apparatus configurations or pressing apparatuses such as ECA pressing are possible and all are within the scope of the present disclosure.
[0051] Referring now to FIG. 5 there is shown a perspective view of an aluminum first sacrificial material 60 and a work piece 62 using an aluminum second sacrificial material and a nickel work piece. As can be seen by the figure, the nickel work piece has undulations 66 on a first lateral side 64 that are indicative of a shearing process. The undulations 66 indicate that the first lateral side 64 saw substantially no friction from the die cavity 36 or die component and a homogenous amount of undulations are present. The undulations 66 are present along substantially the entire lateral side 64 and are only absent only a slight proximal distance from a top surface 68 and a bottom surface 70 . This indicates that the friction from the first die component 32 is confined to the top and the bottom surfaces 68 , 70 . Referring now to FIGS. 6 and 7 , there is shown a microscopic view of the nickel work piece 62 of FIG. 5 . Diffraction patterns corresponding to FIG. 6 are shown in FIGS. 8 and 9 . Straight arrows connect the diffraction patterns to the areas from where they were obtained. The diffraction pattern from the central dark region in FIG. 6 corresponds to a zone axis close to about 110. The diffraction pattern from the area surrounding the central dark area region in FIG. 6 corresponds to a zone axis close to about 122. These two zone axes are at an angle of about forty five degrees. Hence, the central dark area in FIG. 6 is definitely a nano-grain. The nano-grain has a dimension of about 60 nanometers.
[0052] It should be understood that the foregoing description is only illustrative of the present disclosure. Various alternatives and modifications can be devised by those skilled in the art without departing from the disclosure. Accordingly, the present disclosure is intended to embrace all such alternatives, modifications and variances. The embodiments described with reference to the attached drawing figures are presented only to demonstrate certain examples of the disclosure. Other elements, steps, methods and techniques that are insubstantially different from those described above and/or in the appended claims are also intended to be within the scope of the disclosure. | A method of making nano/sub-micron sized grains in a work piece material having a lateral side has the steps of providing a die. The die has an entrance channel with a longitudinal axis and an exit channel. The entrance channel and the exit channel are connected to one another to form an angle. The method has the step of providing a first sacrificial material with a complementary size to the work piece and placing the sacrificial first material and the work piece in an entrance channel. The first sacrificial material and the work piece are aligned with the longitudinal axis. The method has the step of extruding the combination of the first sacrificial material, and the work piece through the intersection of the entrance and the exit channels. The resulting shear deformation forms the nano/sub-micron sized grains in the work piece. This configuration reduces frictional effects thereby producing homogenous nano grain structure. This configuration reduces applied load and enables equal channel angular extrusion of thin sheets. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority from U.S. Provisional Patent application Ser. No. 61/060,717 entitled “Nanofabricated Structured Diamond Abrasive Article”, filed Jun. 11, 2008, which is incorporated herein by reference in its entirety.
TECHNICAL FIELD
Some embodiments are related to methods and an article for abrasion or conditioning of polishing pads and more particularly to methods of manufacture of precision microfabricated or nanofabricated diamond abrasive surfaces with designed placement of geometrical protrusions capable of generating abrasion of designed shape and size.
BACKGROUND OF THE INVENTION
Chemical Mechanical Polishing or Planarization (CMP) is a planarization method used in the semiconductor industry and in other industries such as the optical and flat panel polishing industries, which typically involves removal of material by a combination of relatively gentle abrasion of the layer being planarized (e.g. a Si wafer coated with a metal or dielectric layer) by a polishing pad (composed of a polymer or other relatively soft material) in the presence of a chemically active slurry. The slurry typically contains abrasive nano-particles in colloidal suspension and a reactive chemical agent (e.g. an oxidizer, such as hydrogen peroxide for planarizing metal layers) whose reaction with the planarizing layer is facilitated by the mechanical action of the abrasive particles and a polishing pad typically designed in a particular structure or within a range of roughness. During the CMP process, the surface of the polishing pad may be gradually saturated with polishing nanoparticles, polishing debris and portions of abraded pad material, thus potentially increasing the contact area to an extent that modifies the removal rate of the planarizing material and/or increases the rate of defects of the planarization process through scratching of various sizes. In addition, the polishing pad surface can be abraded leading to a less controlled polishing process of the substrate being removed. Thus to perform a controlled and effective planarization process, these abrasive particles may need to be periodically removed from the polishing pad surface and the pad surface regenerated to a desired surface roughness and rate of defects. Such an action may be accomplished using a conditioning disk or CMP pad conditioner. Due to the hardness of typical abrasive particles and to increase its practical lifetime, the conditioning disk is often fabricated of a hard material, such as diamond. The uniformity and reproducibility of the CMP process often depends on the uniformity and reproducibility of the conditioning process.
Simple conditioning disks often use diamond grit (diamond particles of size from a few microns to a few tens of microns, selected by sieving though filters with different mesh sizes) incorporated into a metal layer (typically formed by electroplating). Such disks may have a Gaussian distribution of diamond particle sizes with a typical standard deviation of 15-20% of the maximum grit size. If, for a given applied force during the pad conditioning process, the penetration depth of the grit into the pad is less than 2-3 standard deviations of the grit height, a substantial number of grit particles (possibly less than 3%) may not touch the pad at all, thus leading to large variations in the uniformity of the pad conditioning process. Metal embedded diamond grit particles can also loosen and fall off, generating scratches or other defects on the substrates that are being planarized.
To overcome these problems and to lengthen effective work life, some conditioning disk manufacturers use CVD diamond to embed larger diamond particles, which are typically screened to reduce the distribution of their sizes. The extent of improvement can be measured, for example, by the number of wafers that can be processed with the same pad, which typically increases from 250 to 300 for the superior CVD diamond-embedded conditioners. However, for a range of applications, such as damascene and double damascene technologies, and as feature dimensions for silicon process technology continue to shrink in the sub-100 nm range, even such improved conditioning technology may still be prone to limitations imposed by irreproducibility in CMP removal rates and pad lifetime. Another issue with these embedded grit pads is that during the wear process of the conditioners, some of the embedded diamond particles may break or be dislodged. Since they might be quite large (e.g. 10-50 μm) hard diamond particles, they can be a significant source of defects on wafers as they are known to cause large scratches on polishing surfaces which can cause failure or reliability problems with surfaces polished by the pads being conditioned.
U.S. Pat. No. 6,076,248 describes a micro-structured surface with individually “sculpted” abrasive regions arranged in irregular arrays. It is primarily directed at the manufacture of a “master tool” for the preparation of other abrasives. It describes the individual sculpting of each abrasive region, i.e. many individual sculpting events. It does not describe a diamond abrasive structure (or diamond geometrical protrusion) covered surface.
U.S. Pat. No. 5,152,279 describes an abrasive surface with abrasive particles embedded in a surface in a roughly predetermined manner. U.S. Pat. No. 5,107,626 describes the method of using the abrasive article of U.S. Pat. No. 5,152,279 to provide a patterned surface. U.S. Pat. No. 6,821,189 describes a similar abrasive to the previous two patents but it also includes a diamond-like carbon coating. These patents do not discuss a method to tightly control the size and placement of the geometrical protrusions (sometimes referred to as “grit” in these various abrasive patents), on the surface.
US patent application 20050148289 describes CMP micromachining. It describes flexible polishing pads to aid in micromachining. Such polishing pads may benefit from embodiments presented here, both in terms of precision and in length of work life.
U.S. Pat. No. 7,410,413 describes another method of creating an abrasive article including the formation of “close-packed pyramidal-shaped composites”. This abrasive patent discusses the mixing and formation of a composite of abrasives and a binder. This patent does not describe the exact placement of each geometrical protrusion. Neither does it describe methods to select in advance or design a placement location, shape and size for each geometrical protrusion.
SUMMARY
Some methods described herein are designed to produce precision microfabricated or nanofabricated abrasive articles or polish pad conditioners. Such abrasive articles include a plurality of raised geometrical protrusions which produce abrasive action or material removal when placed into contact with a target surface with a given downward force and move in relation to the target surface. In some embodiments, the plurality of geometrical protrusions are preselected (or designed) for a specific sizes, shapes and placements on an abrasive article substrate. The geometrical protrusions are placed on the abrasive article substrate surface in tightly controlled placements and therefore it is possible to design or specify a series of protrusion placements that are highly regular to produce highly controlled abrasive action or more predictable removal rates.
In some embodiments, micro-fabricated (or nano-fabricated) conditioning disks or substrates with extremely narrow and carefully designed “grit” (i.e. geometrical protrusion) size distributions and shapes can be used. Some embodiments describe methods of fabricating such conditioners or structured abrasive articles. Such embodiments may comprise arrays of diamond tips, posts or other geometrical protrusions of well-controlled and designed geometry and distribution/placement across a disk or substrate surface. Such disks may combine the durable and monolithic nature of a diamond abrasive surface which impedes the loss of grit “particles” (abrasive structures or geometrical protrusions made of or coated with diamond), with ultra-narrow height distribution or controlled size distribution and placement of grit particles/geometrical protrusions. The geometry and surface density of the diamond spikes/geometrical protrusions can also be very well controlled and optimized, with negligible variation from conditioning disk to conditioning disk or from precision abrasive surface to precision abrasive surface.
Such structured diamond abrasives of predetermined size and shape can also be used in other applications requiring precision, reproducibility and long work-life. Such applications include, for example, the precision manufacture of other abrasives, precisely controlled nano-abrasion of surfaces (e.g. hard-drive rigid-disk surfaces, optical surfaces, MEMS structures, and aerodynamic/hydrodynamic surfaces of low drag coefficient).
BRIEF DESCRIPTION OF DRAWINGS
In the drawings, identical or corresponding elements in the different Figures have the same reference numeral.
The invention is described by the following detailed description and drawings wherein:
FIG. 1 . Diamond molding process for the production of precision abrasive articles or conditioners.
FIG. 2 . Fabrication of arrays of diamond spikes/geometrical protrusions for a conditioning disk or other abrasive article, using hard-mask etching of a thick diamond layer according to the 2nd embodiment of the invention.
FIG. 3 . Fabrication of diamond-coated arrays of tips or geometrical protrusions for conditioning CMP disks according to 3rd embodiment of the invention.
FIG. 4 . Array of diamond pyramids formed using a method according to a 1st embodiment of the invention
FIG. 5 . Diamond abrasive geometrical protrusions formed according to the 3rd embodiment of the invention.
FIG. 6 . Geometrical protrusions for an abrasive article formed according to a 3rd embodiment of the invention.
DETAILED DESCRIPTION
FIG. 1 depicts a diamond molding process for the production of precision abrasive articles or conditioners. In FIG. 1 a , an exemplary Si substrate 100 is patterned with crystallographic wet etching to form wedges 101 . FIG. 1 b shows an additional step for the formation of a sharpened mold. In this case, the thermal oxide 110 is grown inside the mold 101 and on the substrate 100 surface outside the mold. The resulting surface comprises a sharpened point 111 . FIG. 1 c shows the deposition of a diamond layer 120 into the sharpened mold or groove area. The molded diamond material forms a sharp tip 121 . FIG. 1 d shows a final step to remove both the substrate material 100 and the thermal oxide 101 leaving the released molded diamond material 130 with a sharpened point 131 .
FIG. 2 depicts fabrication of arrays of diamond spikes/geometrical protrusions for a conditioning disk or other abrasive article, using hard-mask etching of a thick diamond layer. FIG. 2 a depicts a photoresist cap 200 ; a masking layer 201 comprising SiO 2 ; a diamond layer 202 , and a silicon substrate 203 . FIG. 2 b depicts etching of the masking layer, with some erosion of the photoresist cap. FIGS. 2 c - e depict etching of the diamond layer, with the formation of a sharp tip 241 .
FIG. 3 depicts fabrication of diamond-coated arrays of tips or geometrical protrusions for conditioning CMP disks. FIG. 3 a depicts a silicon substrate 300 with a photoresist layer 301 comprising SiO 2 disposed thereon. FIGS. 3 b - 3 d depict etching by, for example, wet chemical etching, reactive ion etching, or the like. FIG. 3 e depicts formation of a sharp tip 340 .
FIG. 4 depicts an array of diamond pyramids. FIG. 4 a depicts an array of ultrananocrystalline diamond pyramids with four sides. Pyramid heights are approximately 7 μm. Pyramid density is approximately 250,000 protrusions per square centimeter. In FIG. 4 b , pyramid heights are approximately 2.8 μm. Pyramid density is approximately 2,777,777 protrusions per square centimeter.
FIG. 5 depicts diamond abrasive geometrical protrusions. Scale bar denotes 1 μm. UNCD spike heights range from below 1 μm to approximately 2 μm.
FIG. 6 depicts various geometrical protrusions for an abrasive article. FIG. 6 a depicts an UNCD-coated Si microtip. In FIG. 6 b , the structure of FIG. 6 a has had its tip removed and the Si core of the structure has been etched by a HF-HNO 3 solution. FIG. 6 c is a top view of the structure of FIG. 6 b , showing the conformal nature of the approximately 300 nm thick coating. FIG. 6 d depicts a series of UNCD-coated Si tips, with coating thicknesses ranging from approximately 0.1 μm to 2.4 μm. FIG. 6 is taken from N. Moldovan, O. Auciello, A. V. Sumant, J. A. Carlisle, R. Divan, D. M. Gruen, A. R. Krauss, D. C. Mancini, A. Jayatissa, and J. Tucek, Micromachining of Ultrananocrystalline Diamond , Proc. of SPIE 2001 International Symposium on Micromachining and Microfabrication, 22-25 Oct. 2001, San Francisco, Vol. 4557, pp. 288-298.
A first embodiment comprises starting with a Si wafer substrate, followed by SiO 2 growth (e.g. ˜0.3 μm) by thermal oxidation, followed by lithographic patterning and crystallographic wet etching of the exposed substrate surface with square or circular windows of size ˜2 to 30 μm (and preferably of size 5-20 μm, e.g. 14 μm), in regularly-spaced patterns or assembly to produce a desired density of spikes/geometrical protrusions (e.g. ˜300,000/cm 2 ). However, any desired pattern can be designed into the lithographic step to produce an essentially unlimited range of possible arrangements and designed structure placements, sizes and shapes. The SiO 2 is then removed by buffered HF or oxide CMP. Optionally, a seeding enhancement layer (such as 50 nm of sputtered W) can be deposited before diamond deposition. Seeding with a suspension of diamond nanoparticles (prepared, e.g., by ultrasonication and rinsing, with detonation diamond powder dissolved in methanol, or with ultra-dispersed diamond—UDD solution) is performed, then diamond growth is performed by CVD (for illustration and not for limitation, UNCD is deposited by HFCVD) to a thickness of 2-20 μm (more preferably 5-10 μm). A SiO 2 layer (preferably BPSG) is then deposited by CVD in a thickness to fully fill the pyramids (12 μm for the typical case of 10-μm-deep V-groves generated by the previously-mentioned typical window size of 14 μm), then polished by CMP for planarization. Glass frit bonding is then performed, for example by following the method of U.S. Pat. No. 7,008,855 to Baney et al., using a low melting temperature glass, e.g. Paste FX 11-036, produced by Ferro Corporation, deposited onto the substrate by screen printing followed by thermal conditioning for 30 min at 500° C. in a nitrogen atmosphere. The preferred bonding substrate is a highly planar ceramic substrate. The bonding itself can be performed without microscope alignment (only visual alignment, to overlap the two plates). Following the bonding process, the Si mold-wafer is then removed by Tetra-Methyl Ammonium Hydroxide (TMAH).
Abrasive structure (geometrical protrusions) sizes and shapes are dependent on the particular application or material being abraded. However, for abrasive purposes, a geometrical protrusion height of about 0.1-500 μm, or more preferably about 1.0-50 μm is desirable. The amount of downward force applicable to a given surface to generate abrasion from the abrasive articles manufactured using this method are dependent upon the material being abraded and the designed size, shape, uniformity and placement of the geometrical protrusions on the surface, however a downward force of at least about 0.5 psi (˜3.45 kPa), is preferred to generate a reasonable removal rate. Material removal rates of at least about 1 μm per hour are preferred and rates of at least about 100 μm per hour are more preferable, but this will depend upon the amount of downward force applied and the designed sizes, shapes and placements of the geometrical protrusions.
As a variant of this embodiment, it is possible to form “desharpened” protrusions using the method described above. Instead of depositing a material comprising diamond on top of the SiO 2 , some oxide is instead first removed. Diamond is thereafter deposited to produce structures with desharpened points.
A second embodiment comprises direct etching (or forming) of spikes/geometrical protrusions into a thick diamond layer, for example from a thick UNCD layer (e.g. ˜15 μm) deposited by HFCVD onto a planar ceramic or silicon substrate. This is followed by: a piranha clean of the UNCD layer (which also has as a goal to modify the hydrogen termination on the diamond surface into an oxide (—O) or a hydroxyl (—OH) termination which can provide for enhanced adhesion with a metallic or hydrophylic materials; deposition by PECVD of a SiO 2 layer (e.g. ˜1.5 μm); CMP planarization (e.g. with a Cabot Microelectronics SS12 slurry and a Rohm and Haas, IC 1000 polishing pad, under 20 psi downward force polishing pressure) by removing ˜1 μm of the SiO 2 , to leave behind a smooth, planar surface of SiO 2 , acceptable for lithography. This film is then patterned lithographically and etched (e.g. with CHF 3 —O 2 reactive ion etching) into an array of square islands, (e.g. ˜4 μm in size), then the pattern is transferred into UNCD to a depth of ˜12 μm using a O 2 —CF 4 Inductively Coupled Plasma-Reactive Ion Etch (ICP-RIE) plasma etch (typical ICP-RIE conditions: 50 sccm O 2 , 2 sccm CF 4 , 3 kW ICP, 5 W RIB). The degree of isotropy of the etch can be controlled by controlling the temperature of the substrate (e.g. ˜400° C.) to vary the aspect ratio and depth of the spikes/geometrical protrusions until the SiO 2 cap falls off, leaving behind a sharpened diamond tip. Typical desired surface densities of spikes/geometrical protrusions for this method are 1,500,000/cm 2 . If the structures are designed in a larger size (e.g. >20 μm or a width greater than the thickness of the deposited diamond) which do not etch laterally in an amount sufficient to remove the SiO 2 cap, then the height of the geometrical protrusions above the substrate in the resultant abrasive array will be approximately equal to the thickness of the diamond as deposited. If the designed size of the geometrical protrusions is small enough or significantly smaller than the thickness of the diamond layer (e.g. 4 μm for the initial dimension of the structures compared to 12 μm for the diamond layer thickness as in the example above) to allow the removal of the SiO 2 cap, then the resultant height of the geometrical protrusions (or spikes) will be dependent on the amount of over-etching and in the original designed size of the cap. In general, for these smaller structures (e.g. smaller than the thickness of the deposited diamond), the height of the resultant protrusion above the substrate surface will be less for the smaller structures since they will on average receive more over-etching. The larger structures will tend to be taller and the smaller structure shorter (see for example FIG. 5 ).
Abrasive structure (geometrical protrusions) sizes and shapes are dependent on the particular application or material being abraded. However, for abrasive purposes the preferred heights of protrusions are similar to those of the previous fabrication method, i.e. a geometrical protrusion height of about 0.1-500 or more preferably about 1.0-50 μm is desirable. The amount of downward force applicable to a given surface to generate abrasion from the abrasive articles manufactured using this method are dependent upon the material being abraded and the designed size, shape, uniformity and placement of the geometrical protrusions on the surface, however a downward force of at least about 0.5 psi (˜3.45 kPa), is preferred to generate a reasonable removal rate. Material removal rates of at least about 1 μm per hour are preferred and rates of at least about 100 μm per hour are more preferable, but this will depend upon the downward force applied and the designed sizes, shapes and placements of the geometrical protrusions.
A third embodiment comprises preparing an etched or fabricated of Si or other patternable substrate to form spikes/geometrical protrusions that may then be covered with a diamond film or layer. For example, a Si wafer may be covered with a layer of thermal oxide, e.g. ˜0.5 μm in thickness, or a layer of CVD oxide or nitride or other materials that are resistant to an etch chemistry used to etch silicon. The oxide (or alternative material resistant to silicon etch) may then be patterned into an array of square (or other desired shape) islands, each of them being e.g. ˜6 μm×6 μm in size, by wet etching, with a buffered HF etch, NH 4 F:HF 1:6, through a photoresist mask. The Si may then be etched with a SF 6 /O 2 plasma Reactive Ion Etch (RIE) (e.g. 50 sccm SF 6 , 5 sccm O 2 , 200 mTorr, 200W) having a slightly isotropic etching nature. The degree of anisotropy may vary from one piece of equipment to another, and depends upon, for example, the plate area and the surface area being etched. Etching may then be performed until the SiO 2 cap is attached to the so-formed Si pyramid at a spot of diameter or width of ˜2 μm (i.e. ˜4 μm of the original ˜6 μm width has been etch away. After this, etching may be continued by a XeF 2 isotropic etch until all the SiO 2 is removed and the caps fall off. The spikes/geometrical protrusions in Si obtained through use of this method may have a height of ˜6 μm. A preferred surface spike/geometrical protrusions density range for this method can be about 10,000 protrusions/cm 2 to about 10,000,000 protrusions/cm 2 in or more preferably about 1,000,000 protrusions/cm 2 .
Abrasive structure (geometrical protrusions) sizes and shapes are dependent on the particular application or material being abraded. However, for abrasive purposes the preferred heights of protrusions are similar to those of the previous fabrication method, i.e. a geometrical protrusion height of about 0.1-500 μm, or more preferably about 1.0-50 μm is desirable. The downward force applicable to a given surface to generate abrasion from the abrasive articles manufactured using this method are dependent upon the material being abraded and the designed size, shape, uniformity and placement of the geometrical protrusions on the surface, however a downward force of at least about 0.5 psi (˜3.45 kPa), is preferred to generate a reasonable removal rate. Material removal rates of at least about 1 μm per hour are preferred and rates of at least about 100 μm per hour are more preferable, but this will depend upon the downward force applied and the designed sizes, shapes and placements of the geometrical protrusions.
Various shapes capable of abrading a surface can be designed with these fabrication methods. However, one preferred set of shapes than can be used to great effect and that provide strength and relative ease of design, is that of 3, 4, 5, or 6-sided pyramids with relatively sharp tips or 3, 4, 5, or 6-sided truncated pyramids with relatively flat tops. Other types of geometrical protrusions can be advantageous, including cones with substantially circular or elliptical bases and sharpened points.
The precision microfabricated conditioners or abrasive articles made using the methods described above, can be designed with specific arrangements of geometrical protrusions to select particular abrasive properties. For example, if elongated geometrical protrusions in the shape of lines or “fences” (or similar structures with one dimension longer than another at the exposed edge, or highest point of the protrusion) are all aligned on the abrasive article surface the abrasive properties generated from this arrangement can be substantially different depending upon whether or not they are used to abrade a surface along the axis of the protrusion lines or at an angle with respect to the axis of the protrusion lines. It may be advantageous to abrade a pad surface with such lines of abrasive protrusions at approximately right angles to the motion of a pad surface underneath the protrusions.
The above-mentioned embodiments can be used to form structures for abrasion including CMP conditioning heads or other precision abrasives or for alternative applications. An example of an alternative application for these assemblies of microfabricated structures is in the area of stamping or manufacturing of articles that are pressed into a desired shape using a stamping press or mold. Such manufacturing methods are commonly used in the automotive and consumer products industries to stamp metallic and polymeric materials into desired shapes. Elevated temperatures are sometimes used to soften the target material and facilitate the stamping process. The hardness and temperature range of diamond materials and the small microstructured size of the structures created using the method described above, raises the possibility of using these designed assembly of structures to form metallic or polymeric materials into desired shapes at the micron or nanometer scale. It is therefore possible that these methods may lead to quick and inexpensive manufacturing methods for MEMS (Micro-Electro-Mechanical Systems) and NEMS (Nano-Electro-Mechanical Systems) using assemblies of diamond structures formed using the methods described herein. The range of structure heights for these may be broader than for abrasive applications. One possible range of heights of the structures for MEMS and NEMS applications would be ˜0.1 μm to 10 μm while for larger scale applications such as consumer products, a range of 1 μm to as much as 5 mm (5000 μm) may be desirable.
Another advantage of the methods of creating abrasive articles or conditioners with the methods described herein with ultrananocrystalline diamond (UNCD) of average grain size ˜2-5 nm, is that abrasive wear of the surface tends to cause failure along grain boundaries and to dislodge individual debris particles of a size approximately equal to the average grain size. Since the average grain size here can be very small (˜2-5 nm), preferably less than 100 nm, and more preferably less than 10 nm, and most abrasive applications are at larger dimensions, these dislodged grain debris are usually too small to cause damage or defects on such surfaces (e.g. scratches or gouges). Larger grain size diamond tends to dislodge under abrasive wear conditions with much larger debris size which are more likely to cause scratches or gouges of a size approximately equal to the size of the particle. Large grain size diamond films, e.g. microcrystalline diamond, grain size can be as high as 1-10 μm. The resultant scratches or defects would therefore be several orders of magnitude larger and be of much greater concern to a precision abrasive manufacturing process.
Although embodiments have been described and illustrated in detail, it is to be clearly understood that the same is by way of illustration and example only and not to be taken by way of limitation, the scope of the present invention being limited only by the appended claims. | The present invention describes a microfabricated or nanofabricated structured diamond abrasive with a high surface density array of geometrical protrusions of pyramidal, truncated pyramidal or other shape, of designed shapes, sizes and placements, which provides for improved conditioning of CMP polishing pads, or other abrasive roles. Three methods of fabricating the structured diamond abrasive are described: molding of diamond into an array of grooves of various shapes and sizes etched into Si or another substrate material, with subsequent transferal onto another substrate and removal of the Si; etching of an array of geometrical protrusions into a thick diamond layer, and depositing a thick diamond layer over a substrate pre-patterned (or pre-structured) with an array of geometrical protrusions of designed sizes, shapes and placements on the surface. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention provides a method for reducing, with a minimal loss of relevant information, the quantities of data in a data set from which a pattern of data must be recognized.
2. Description of the Prior Art
A data set can contain an array of elements such as pixels or picture elements in an image, each element of which can adopt a number of values, here called information values or codes. The importance of recognizing patterns in data sets is great. If the data set contains for instance pixels of a typed or handwritten text, the separate letters of this text can be recognized by pattern recognition. Even when noise is present in the image for recognition it is often still possible to recognize the original patterns. If the data set is for instance a medical photograph, cell abnormalities or cell tumours can be recognized at an early stage by pattern recognition.
In the prior art diverse methods are known for recognizing patterns in data sets. There are statistical methods which however cannot process very well the structural information in the links in complex patterns. There are for instance also descriptive methods, wherein the attempt is made to define the properties of the patterns for recognition. These methods result in problems when the patterns for recognition are complex. Use can also be made of neural networks to recognize patterns. However, the use of neural networks to recognize patterns in large data sets comes up against limitations in the capacity of the present computers with which the neural networks are computed.
SUMMARY OF THE INVENTION
The method according to the present invention extracts relevant information from the data set, based on the internal information content which is estimated from the statistical properties which are present in a training set of already known (a priori) patterns provided to the device of the invention during a training phase. Non-relevant or superfluous information is ignored according to the present method. The size of the data set is hereby reduced, wherein a minimal loss of relevant information occurs.
The present invention relates to a method and device for reducing the quantity of digital information in a data set for the purpose of pattern recognition. The method comprises the following steps of:
determining during a training phase digital a priori information values associated with at least one known pattern. These a priori information values form a training set which is used in a later step in the recognition of patterns.
determining digital information values of first elements associated with a pattern for recognition. The first elements can for instance be pixels of an image, in which image a pattern must be recognized. Digital information values are then for instance the grey tone values or colour values of the pixels.
grouping two or more first elements;
pairing the grouped first elements into second elements, wherein the number of digital information values for each second element is at least doubled;
for each second element, on the basis of pattern information from the training set formed in the training phase, merging a minimum of two digital information values into a reduced second element with a reduced number of information values. The pattern information is calculated on the basis of a statistical estimate of the probability that the digital information value is associated with a particular pattern. This statistical estimate is calculated from the data of the training set.
The merging of information values referred to in the final step takes place in a manner such that as little pattern information as possible is lost. On the basis of the a priori known possible patterns, the best estimate can be calculated of the probability that a combination of a determined information value and a determined pattern occurs. On the basis of the calculated estimate of the probability of all possible combinations of information values and patterns, a decision criterion is formulated with which the combination of pattern and information value can be determined which yields a minimal loss of pattern information when merged.
BRIEF DESCRIPTION OF THE DRAWING
The present invention will be described hereinbelow with reference to a preferred embodiment. The embodiment is illustrated in figures, in which:
FIG. 1 is a schematic overview of the device according to the present invention;
FIG. 2 shows a part of an image of a pattern for recognition;
FIG. 3 shows lists of the number of times that a combination of pattern and pixel value occurs;
FIG. 4 shows schematically the merging of pixels;
FIG. 5 illustrates the conversion of the coding of the information value after pairing;
FIG. 6 shows a graph which shows the progression of the total information as a function of the pairing and merging steps.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a device according to the present invention. The device comprises inter alia:
a computer 1 with which the methods according to the present invention to be explained below can be performed.
input terminal 2 for input into the computer of digital information values; the input can take place using a keyboard. However, the input generally originates from an external electronic device such as pixels from a video camera, scanner and the like.
connections 3 between the computer, input terminal 2 and output terminal 4 enabling data transfer therebetween.
output terminal 4 for output of the results of the method according to the present invention.
FIG. 2 shows an example of an image consisting of nine pixels which can adopt a value “1” (=black) or a value “0” (=white). For the sake of simplicity a black-and-white image, therefore without grey tones or colours, is taken as starting point. In the figure three pixels are designated respectively R, S and T. Suppose that two patterns, i.e. “/” and “\”, are to be recognized by the system. First of all, in the so-called training phase or preparatory phase the value of all pixels is determined, both when the pixels display the pattern “/” and when the pixels display the pattern “\”. The results of the training phase form the training set, in which a list is compiled per pixel which contains all combinations of patterns α and values i of pixels.
FIG. 3 shows these lists for the three pixels R, S and T. On the basis of the lists the frequency is determined with which the combinations of pixel values and patterns for recognition occur in the relevant pixel of the training set.
In the example each pattern has the same combination of pixel values. This is generally not the case, however. In the recognition of letters for instance, it is very well possible that a determined letter has multiple variants, since letters can be represented in different ways. It is hereby possible for different combinations of pixel values to occur in the same pattern (“letter”).Although a letter can have a plurality of representations, a large degree of mutual similarity is however present.
From the lists shown in FIG. 3 can be determined how often a combination of a particular pattern and a pixel value occurs. The number of times that such a combination occurs is designated with “n R iα , wherein R represents the relevant pixel, i represents the digital pixel value and a represents the pattern in question. Table 1 shows for pixels R, S and T the corresponding values for n iα .
TABLE 1
Number of times that a combination of pattern and
pixel value occurs.
element R
element S
element T
n 0/
2
2
0
n 1/
0
0
2
n 0\
0
2
2
n 0/
2
0
0
For all pixels and all possible pixel values the probability P iα is then calculated of these occurring in a particular pattern. The probability is calculated using the so-called Laplace Samplesize Corrector: p i α = p α n i α + 1 ∑ i ( n i α + 1 )
Using the above expression table 2 shows for the three pixel R, S and T the probabilities per pixel value and pattern. The probabilities for the other pixels can be calculated in analogous manner.
TABLE 2
Probabilities per pixel value and pattern for
pixels R, S and T.
pixel R
pixel S
pixel T
p 0/
⅜
⅜
⅛
p 1/
⅛
⅛
⅜
p 0\
⅛
⅜
⅜
p 0/
⅜
⅛
⅛
The pixels are subsequently grouped into groups of two pixels. Since the correlation, between adjacent pixels is generally greater than between pixels far removed from each other, adjacent pixels are preferably grouped. A grouped pair of pixels is then combined into a new pixel. The total number of pixels is hereby halved. The quantity of possible pixel values is however doubled. No information is hereby lost. The grouping of pixels can otherwise take place in a number of different ways: for instance initially between pixels located on a horizontal line and subsequently between pixels located on a vertical line. In the example pixels R and S located on a horizontal line are paired.
FIG. 4 shows the process of pairing pixels. In this figure numbered parallelograms designate the pixels. At each step from the one layer to the other layer (i.e. after each pairing) the number of pixels halves, until in this case after pairing four times only one pixel remains.
A new coding can be used for the possible combination of pixels. FIG. 5 gives a new coding for the different combinations of pixels R and S. The result of merging two pixels R and S is therefore in this case a single pixel V with pixel value 0, 1, 2 or 3. The probability P ijα of pixel R having the pixel value i, pixel S having the pixel value j and the pattern being equal to α can be determined iteratively or can be approximated by the expression: P ijα = P iα R P jα S P α
Herewith and with the information from FIG. 3 the probabilities for each combination of new pixel values and patterns can be determined. Table 3 shows the results hereof.
TABLE 3
Probabilities per pixel value and pattern for
pixel V
pattern “/”
pattern “\”
p 0/
{fraction (9/32)}
p 0/
{fraction (3/32)}
p 1/
{fraction (3/32)}
p 1/
{fraction (1/32)}
p 2/
{fraction (3/32)}
p 2/
{fraction (9/32)}
p 3/
{fraction (1/32)}
p 3/
{fraction (3/32)}
The above procedure can be repeated, wherein the number of pixels is halved each time, while the number of pixel values is doubled.
Since the number of possible pixel values increases exponentially with the number of successive combinations of pairs of pixels, it may be necessary to reduce this number. This can be effected by merging pixel values to a new pixel value, also referred to as “pruning”. Hereby the original pixel values can no longer be distinguished and it is inevitable that the information contained in the pixel values is lost. The number of pixel values has however decreased. In order to minimize the loss of information due to merging of pixel values, a criterion has been developed to decide which pixel values must preferably be merged.
Since the object of the present preferred embodiment of the invention is the recognition of patterns, the loss of information concerning the patterns due to merging of the pixel values must be minimal. Pattern information can be described as follows: - ∑ i ∑ α p i α ln ( p i α P i )
The loss of pattern information from merging of information values i and i′ therefore amounts to: - [ ∑ α p i α ln ( p i α P i ) + ∑ α p i ′ α ln ( p i ′ α p i ′ ) - ∑ α ( p i α + p i ′ α ) ln ( p i α + p i ′ α P i + p i ′ ) ]
This loss of information is determined for all combinations of pixel values i and i′ for a particular pixel. In table 4 the information loss is determined for all combinations of pixel values of pixel V with reference to the example above.
TABLE 4
Loss of information for all possible combinations
of pixel values
Combination
Loss of information
0 and 1
1.6653 10 −16
0 and 2
−0.09811
0 and 3
−0.004961
1 and 2
−0.049619
1 and 3
−0.032703
2 and 3
1.6653 10 −16
The pixel values of the combinations of information values with the smallest loss of information are chosen for merging. In this case the combination of 0 and 1 or the combination of 2 and 3, yields the smallest loss of information. When the combination 0 and 1 is chosen, each 0 therefore becomes a 1 or each 1a 0. When the combination 2 and 3 is chosen, each 2 therefore becomes a 3 or each 3 a 2.
By merging the pixel values i and i′ the probability of the merged pixel becomes P i+i′,α =P iα +P i′α .
It is necessary to record in a code list or code book which pixel values have been merged so as to be able to use the information concerning the merging at a later stage during recognition of images. The method of merging pixel values must generally be performed for all pixels individually. The calculations above must therefore be performed for each pixel, wherein the results are stored per pixel in a code book.
If the number of pixel values is still too large after merging, the method can be repeated until the number of pixel values is sufficiently reduced. Thereafter the process of pairing pixels and possible merging of pixel values can recommence.
The methods of pairing pixels and merging pixel values can be repeated as often as necessary until all pixels are paired and the number of pixel values has been reduced to an acceptable level.
FIG. 6 shows a graph in which the total pattern information of an image is plotted against the steps of pairing pixels (designated with C) and merging or pruning (designated with S) of pixel values. At each step of pairing pixels the pattern information increases on account of the strong correlation between the pixels of the images for recognition. At each step of merging or pruning pixel values (a small quantity of) pattern information is lost. After having performed pairing and merging so often that the whole image is processed, the value of the pattern information converges to a value close to zero since recognition is practically perfect. The final value of the pattern information (i.e. the difference with a zero value) is the recognition error. This value is a cumulation of all information losses due to the merging of pixel values and due to an intrinsic ambiguity resulting from the limited statistical properties of the training set.
The pairing of pixels and merging of pixel values of the above described preferred embodiment can be repeated as often as necessary until an input suitable for neural networks results. The recognition of the patterns is then taken over by the neural network. The reason that neural networks cannot be applied directly on pixels (therefore without processing according to the above described method) is that the number of nodes of the neural network would become much too large to enable recognition in rapid manner of a pattern, given the present computer technology.
A pattern in an image can also be recognized directly by pairing pixels and merging pixel values. In the described preferred embodiment of the method and device only correlations in each layer between adjacent, closely situated elements are examined, correlations with remote elements takes place later in “deeper” layers. The data reduction according to the method forms a layered structure, wherein depending on the environment (context) elements are combined, or the pattern recognition is brought about using contextual correlation. | A method for reducing the quantity of digital information in a data set for the purpose of pattern recognition, comprising: a) determining digital a priori information values associated with at least one known pattern; b) determining digital information values of first elements associated with a pattern for recognition; c) pairing two or more first elements into second elements, wherein the number of digital information values for each second element is at least doubled; d) for each second element, on the basis of the digital a priori information values, merging a minimum of two digital information values into a reduced second element with a reduced number of digital information values. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to methods of and apparatus for positioning pallets, and more particularly to a method of and apparatus for positioning a pallet whereby the pallet disposed upon the roller chains of a horizontally disposed free flow conveyor is able to be stopped at a required position with a high degree of accuracy.
2. Description of the Prior Art
In a production or an assembly line of electrical parts, conventionally, the free flow conveyor has favorably been put into practical use. This horizontally disposed free flow conveyor mounted upon a conveyor frame consists of a large number of pallets which are freely loaded on endlessly circulating roller chains, and feeds in order a printed circuit board for electrical parts held on a pallet toward a work station, where every pallet is securely stopped at a required position before automatic insertion of electrical parts with the aid of an inserter or other similar devices is generally performed.
The prior art free flow conveyors, however, have demonstrated substantially great technical difficulties in their positioning operations to securely stop the pallet at the required position. And to minimize this difficulty various devices or systems have been brought forward. For example, a device for positioning a pallet in x- and y-directions, as shown in FIG. 1, was proposed to fit a wedge-shaped stopper 14 into a triangular notch 12 cut away on one side edge of a pallet 10. But this device contained disadvantages in requiring intricate mechanisms as well as installation costs because another arrangement was required to control the height in the z-direction. Such being the case with the conventional pallet positioning device, as a result of incorporating an independently driving mechanism requisite for x-, y-, and z-dirctions respectively, the positioning operation must be performed with a two-step action cycle, and thus another disadvantage existed in taking much time for positioning the pallet.
OBJECTS OF THE INVENTION
Accordingly, it is an object of the present invention to eliminate the above-described disadvantages accompanying the previously known devices, namely, not only to securely obtain highly accurate positioning of a pallet with one-step action but to provide a method of positioning the pallet and a novel device therefor capable of shortening the cycle time as well.
SUMMARY OF THE INVENTION
In accordance with the present invention, to attain this object, the method of positioning the pallet is characterized by which: an oncoming pallet on a free flow conveyor fed at an indefinite interval is previously detected; the pallet is stopped by means of a stopper at an approximately required position on the conveyor; both x- and y-directions are controlled by means of the elevation of an elevating plate mounted under the required position of the pallet while respectively fitting two or more protruding pieces providing upon the upper side of the plate into bores of flanged members provided upon the underside of the pallet; and the z-direction is also controlled by contact mating of the edges of the flanged members by means of the elevation of the pallet together with the elevating plate against detent block members securely mounted at a required height.
To perform the above-described method of positioning, in the free flow conveyor feeding in order the pallet for work loading, the favorably applied device particularly comprises: a base bridged between an oppositely disposed pair of conveyor frames; a horizontally disposed support plate mounted through means of support members above the base; an air cylinder suspendingly mounted from the lower side of the support plate and having an upwardly extending piston rod extending through a central aperture provided within the support plate; required-height detent block members mounted on the upper side of the support plate upon opposite sides of the center line of the pallet flow; an elevating plate secured onto the piston rod of the air cylinder so as to be vertically movable in a contact-free mode with respect to the detent block members; two or more protruding pieces which are used for positioning the pallet in both the x- and y-directions are secured on the upper side of the elevating plate; flanged members having bores for mating with the protruding pieces and positioning the pallet in the z-direction by contacting the detent block members; a sensor for detecting an approaching pallet; and a stopper for stopping the pallet at the approximately required position by contact with the flanged members mounted on the pallet.
BRIEF DESCRIPTION OF THE DRAWINGS
The various features and novelty which characterize the present invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, its positioning advantages, and specific objects attained by its method, reference should be had to the accompanying drawings. and descriptive matters in which there are illustrated and described preferred embodiments of the present invention, wherein:
FIG. 1 is a schematic view of the pallet positioning device of the prior art;
FIG. 2 is a schematic top view of the pallet positioning device of the present invention;
FIG. 3 is a cross-section taken on line A--A in FIG. 2;
FIG. 4 is a side view taken in the direction of flow in FIG. 2;
FIG. 5 is a perspective view of the face of the elevating plate;
FIG. 6 is an exploded view in perspective of the relation between the support plate mounted on the base and the elevating plate driven up and down by the air cylinder located thereabove; and
FIG. 7 is a schematic view in perspective of the underside of the pallet used in the device of the invention.
DETAILED DESCRIPTION OF THE INVENTION
With specifiic reference to the form of the invention illustrated in the drawings, the numeral 16 indicates in general the two horizontally disposed conveyor frames installed in a laterally spaced parallel mode with respect to each other so as to leave a required spacing therebetween upon each of which roller chains 18 are provided in upper and lower flights so as to endlessly circulate and run forwardly and backwardly. A large number of rectangular pallets 20 are freely loaded upon the roller chains 18 mounted upon the pair of opposite frames 16, and are transported in the horizontal direction along the frames 16 as the roller chains 18 circulate and operate.
The pallet positioning device according to the present invention, as shown in FIG. 2, is provided in the required location of the frames 16, corresponding to which the work station, not shown, is installed on the side of the frames 16. A suitable inserter or an automatic inserting machine for electrical parts is, for example, provided at the work station, which is, of course, available for manual operations as a working table.
Below the pair of frames 16, as shown in FIG. 4, there is provided a base piece 22 which is installed, at right angles with respect to the direction of the conveyor flow, by means of bolts 24. At an approximately central part of the base 22, there is provided a rectangular bore within which an air cylinder 32, more particularly described hereinafter, is disposed. Above the base 22, a pair of vertically extending cylindrical support members 26 are installed so as to be disposed upon opposite sides of the bore, as shown in FIG. 2, and a horizontally disposed oblong support plate 28 is secured to the upper ends of the cylindrical support members 26. A round aperture 30 is bored within the central part of the support plate 28, the upper end of the extremely small stroke air cylinder 32 (so-called mini cylinder) being in contact with the underside of plate 28, and secured to plate 28, while the piston 34 extends upwardly within aperture 30.
Above the support plate 28, there is provided a rectangular elevating plate 36 which reciprocates upwardly and downwardly with a required stroke. Along the central axes of the pair of support members 26, there is respectively provided a bore of required diameter in which pins 38 are respectively inserted so as to be free sliding therewithin, and the elevating plate 36 is fixedly secured to the top of each pin 38, plate 36 being additionally secured to the free end of the piston rod 34 by suitable fixing means, not shown. Thus, the pins 38 disposed within the bores of the support members 26 function not only as guides which can smoothly guide the elevating plate 36 when the same is elevated above the support plate 28 but also serve as stoppers which can prevent the elevating plate 36 from swivelling with respect to the support plate 28.
Next, within the vicinity of each corner on the upper surface of the elevating plate 36, four protrusions 40, as described hereinafter, are respectively provided to receive a vertical load. Further, the elevating plate 36, as shown in FIG. 5, is provided with two rectangular bores 42 which are disposed upon opposite sides of the central axis line of the conveyor flowpath, and detent block members 44, having an L-shaped cross-section, pass through the bores 42.
As shown in FIG. 5, along the central axis line of the elevating plate 36, at least two protruding pieces 46, which position the pallet 20 in the x- and y-directions, as described hereinafter, are respectively secured to the upper surface of elevating plate 36 with a predetermined spacing therebetween.
On the upper surface of the support plate 28, as shown in FIG. 4, two detent block members 44, having an inverted L-shaped cross-section, are mounted upon opposite sides of the central axis line in the direction of the conveyor flow and also at the required height by means of bolt members 48. And, as shown in FIG. 5, the elevating plate 36 is freely disposed about each of the detent block members having the inverted L-shaped section through means of the two bores 42, and is provided with the piston rod 34 of the air cylinder 32. Thus, when the air cylinder 32 is energized, the piston rod 34 will be extended out of the cylinder 32 and the elevating plate 36 will be elevated by the required stroke, however, the bores 42 are sufficiently large with respect to the detent block members 44 so as to freely pass therearound whereby plate 36 and blocks 44 do not interfere with each other. And, as described above, the two pins 38 which are inserted into the support member 26 so as to be free sliding therewithin can allow the elevating plate 36 to be controlled in the x- and y-directions and be smoothly elevated in a linear manner without pivoting or rotating. As shown in FIG. 4, the elevating plate 36 is also provided with additional guiding members 50 which pass perpendicularly through the base 22 so as to be free sliding therethrough.
In view of the device according to the present invention, a mechanism which is fitted into the detent block members 44 having the inverted L-shaped cross-section is incorporated into the pallet 20, which will be apparent by reference to the following description which discloses further details taken in connection with the accompanying FIG. 7. FIG. 7 is a schematic view in perspective of the underside of the rectangular pallet 20 used in a free flow conveyor, and the flanged members 52 having horizontally extending sides are fixedly secured to pallet 20 along its central axis line with respect to the flow direction of the pallet 20. The buffer pieces 54 comprising highly elastic materials like urethane are respectively attached to both front and rear ends of the flanged members 52, as viewed in the direction of flow of the pallet 20, and there is provided upon the underside of each member 52 a round bore 56a and an oval bore 56b, which are respectively bored thereon so as to have a required spacing therebetween along the central axis line of member 52. The distance between round bore 56a and oval bore 56b is predeterminedly set, so that the distance may be the same as the protruding pieces 46 for positioning the pallet 20 in the x- and y-directions and which, as described above by reference to FIG. 5, extend out from the surface of the elevating plate 36. As shown in FIG. 4, when the pallet 20 supported by the roller chains 18 comes within the vicinity of the work station, the horizontally projecting flanges of the flanged members 52 which are provided upon the underside of the pallet 20 are predeterminedly sized, so that both sides can be smoothly inserted into and pass through the L-shaped regions of the detent block members 44 having the inverted L-shaped cross-sections.
Referring next to FIG. 3, on the upper side of the base 22, there is provided another air cylinder 58 having a configuration as illustrated, and the end of the piston rod 60 which belongs to air cylinder 58 is sized, so that the end may be located slightly below the underside of pallet 20 as well as above the underside of the flanged members 52 when the cylinder is energized, whereby the urethane pieces 54 will be in contact with the end of the rod 60, as illustrated in the drawing. When the air cylinder 58 is reversely energized, the rod 60 will retract into the cylinder 58 and, accordingly, it is apparently understandable that the rod 60 is released from contact with the urethane pieces 54, or in other words, the function as a stopper is complete.
In the next place, the operation and effect of the pallet positioning device in view of the foregoing description of the present invention will be described. In the free flow conveyor, for example, works such as printed circuit boards for tape recorders, not shown, are loaded upon the pallet 20 and fed in order toward the work station as the roller chains 18 operate. When the corresponding pallet 20 comes within the vicinity of the required position on the work station, the pallet 20 is detected with the air of the required detecting arrangements such as a photodelectric switch, or the like, not shown, which transmits a signal to the air cylinder 58 for operation as a stopper; whereby the piston rod 60 is energized so as to extend upwardly by the required stroke and, consequently, the pallet 20 fed on the free flow conveyor is stopped as a result of contact of the urethane pieces 54 provided upon the ends of the flanged members 52 with the piston rod 60.
In consequence of the foregoing actions, the air cylinder 32, which is provided for elevating the plate 36 upwardly and downwardly and which is provided on the support plate 28, is energized, and the piston rod 34 extends and elevates the elevating plate 36 by the required distance. At this time, one of the two protruding pieces 46 which extend out from the upper surface of the elevating plate 36 is fitted into the round bore 56a provided on the flanged member 52, and the other piece 46 is fitted into the oval bore 56b, whereby the pallet 20 is now accurately positioned in both the x- and y-directions. The reason the oval bore 56b is provided so as to be different in shaped from the round bore 56a is to slightly accommodate longitudianl play for only one bore, by which the protruding pieces 46 are respectively fitted easily and securely into the mating bores when the elevating plate 36 is elevated.
In this manner, the pallet 20 is allowed to be stopped at the approximately required position by means of the piston rod 60 acting as a stopper in the state that the flanged members 52 move relative to detent block members 44, and as the elevating plate 36 is elevated, the x- and y-positions of the plate 36 are enabled to be achieved by fitting the protruding pieces 46 respectively into both the round and oval bores, and therefore, the pallet 20 is finally positioned with a high degree of accuracy at the required position of the work station.
With the pallet 20 elevated by the elevating plate 36, the z-direction of the pallet 20 can be controlled through means of the contact of the flanged edges of the flanged members 52 with the inwardly extending leg portions the detent block members 44. The reasons why the four protrusions 40 are respectively provided upon each corner of the elevating plate 36 are that when the elevating plate 36 is reciprocated upwardly and downwardly, the vertical load of the pallet which is loaded with works or devices may be supported by the four protrusions directly in contact with the underside of the pallet 20, and that the pallet 20 may be prevented from sliding in a side-wise direction.
Referring to the foregoing description of the present invention, the method of positioning the pallet and the device thereof provide a secure and highly accurate positioning of the pallet on the conveyor line with a single action by which the cycle time can be shortened. Since the base 22 which supports the proposed positioning device is solely secured on the lower end of the frames 16 by means of the bolts 24, the base can be freely moved along the direction of the conveyor line with the bolts removed. Accordingly, the optimum location suitable for the work station can be freely varied to satisfy the requirements of field-proven FMS (Flexible Manufacturing System) methods.
Although the invention has been described in its preferred method of positioning the pallet and device thereof with reference to the drawings, it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in appended claims but many apparently widely different embodiments of this invention may be made without departing from the spirit and scope thereof. | An apparatus and a method of positioning pallets on roller chains mounted on a free flow conveyor is basically composed of a detector for detecting an oncoming pallet, a stopper for stopping the pallet at an approximately required position, a controller capable of positioning the pallet in the x- and y-directions, and another controller capable of positioning the pallet in the z-direction. With an application of the foregoing method proposed, a device is designed to provide a highly accurate positioning of the pallet with a single device and therefore contributes greatly to an economization of operating costs. | 1 |
REFERENCE TO PARENT APPLICATION
This application is a division of U.S. application Ser. No. 053,439, entitled CONTINUOUS MINING APPARATUS AND METHOD, which was filed on June 29, 1979, now U.S. Pat. No. 4,312,540.
BACKGROUND OF THE INVENTION
This invention is directed to a continuous mining apparatus and method for the underground mining of coal from seams.
In underground coal mining a shaft, hole or tunnel is usually excavated to the coal seam. The miners then develop horizontal entries through the seam of coal so that the coal is mined through tunnels spreading out from the shaft, hole or tunnel. Elevators or other conveying means are used to lower or raise miners and equipment between the mine entrance at the surface and the level of the coal. Similarly, elevators or handling devices lift or convey the coal out of the mine.
The principal method of mining coal today employs a continuous miner which bites into the face of the coal seam and causes the coal to pass from the front of the machine to the rear thereof where it flows into shuttle cars or onto a conveyor belt. The continuous miner operates at the working face of the mine and eliminates separate cutting, drilling, blasting and loading operations called for in conventional mining.
At the working face of the mine roof control methods are used in order to reinforce the roof and prevent its collapse during mining. One popular method of roof control involves the use of mine roof bolts and bearing plates. Such bolts are positioned in holes drilled into the mine roof. When tightened the mine roof bolt functions with the associated bearing plate as a clamp to hold the rock strata together to thus minimize the possibility of a roof fall.
In order to hold the mine roof bolt in place in the mine roof it is necessary to provide for some sort of anchorage system. Various devices are in use including mechanical expansion type anchors or shells and resin anchors, just to name a few.
The placement of mine roof bolts in an underground mine is time consuming. The precise locations of the bolts in the mine roof are set out in an approved roof control plan issued by the U.S. Department of the Interior, Mining Enforcement and Safety Administration. Each mine has its own mine roof control plan depending upon local conditions.
A typical mine roof control plan will call for the placement of mine roof bolts as a part of roof control at approximately five foot centers in the mine roof. Typical plans also provide that in mining the cut, the continuous mining machine shall not be advanced past the last row of permanent supports (bolts) until additional mine roof bolts have been put in place. Typically, only persons engaged in installing temporary supports or mine roof bolts are allowed to proceed beyond the last row of permanent supports or bolts. When installing supports or bolts in the face area typical plans permit workmen to be positioned not more than five feet from a temporary or permanent support.
Roof control methods including the placement of mine roof bolts thus limit the extent to which a continuous miner may operate in mining a cut. In some cases, the continuous miner is permitted to advance only approximately ten feet into the coal face before it must be withdrawn in order to permit miners to install roof support systems.
As a consequence, therefore, of the implementation of safety standards involving mine roof control the continuous miner operates for only relatively short periods of time before roof control measures have to be installed. This necessitates a great deal of movement of the continuous miner from place to place as cuts are made and roof bolts are installed. It is not uncommon in an eight hour shift to experience only two hours of continuous miner operation with the remaining six hours of the shift devoted to movement of the continuous miner and roof control procedures such as bolting.
This invention contemplates a continuous miner and method in which relatively long cuts are made in a coal face (on the order of 80-100 feet) and in which it is not necessary for a miner to work in an unsupported area of the mine. More particularly, this invention contemplates the use of a continuous mining apparatus in which the cutter assembly of the miner can be remotely advanced into the coal face for relatively long distances to enable relatively large amounts of coal to be removed from the seam without the necessity of stopping the miner and moving it to another location to permit mine roof control procedures to be put in place. Rather, applicant's apparatus and method contemplates the taking of relatively long cuts in the seam and the removal of the continuous miner to another location while mine roof control procedures are implemented in the relatively long cut just made.
BRIEF DESCRIPTION OF THE INVENTION
Briefly described, applicant's invention comprises apparatus and methods for the continuous mining of coal from underground seams.
Applicant's apparatus comprises a continuous miner having a cutter assembly, conveyor assembly and base assembly. The cutter assembly is provided with a plurality of cutter means which cooperate with a plurality of augers in order to remove coal from an exposed coal face and cause such coal to be transported to the conveyor assembly. The conveyor assembly of applicant's apparatus is defined by a plurality of telescoping members which provide support for an endless variable length conveyor belt which extends from the base assembly of the apparatus to the cutter assembly. At least one control cable is provided within the telescoping members in order to provide for either extension or retraction of the telescoping members relative to each other. The conveyor assembly serves principally two functions. First, the conveyor assembly provides for expansible or variable length conveyor means between the cutter assembly and the base assembly whereby coal may be transported or carried from the cutter assembly to the base assembly as the cutter assembly is extended outwardly from the base assembly over variable distances. The second function of the conveyor assembly is to provide for crowd means to impart and end thrust to the conveyor assembly forcing it into the exposed coal face. The end thrust is imparted by means of the control cable disposed within the telescoping support members.
The conveyor assembly of applicant's apparatus is supported by a base assembly which includes internal propulsion means in order to provide for movement of the continuous miner. In addition, the base assembly includes substantially vertically oriented hydraulic cylinders which provide for support of the mine roof immediately above the base assembly and, in addition, allow lateral height adjustment of the base assembly in the mine enabling the cutter assembly to be positioned in virtually any vertical location for a mining operation.
Also included within the base assembly of the apparatus of this invention are control means suitable for operator use in connection with the continuous miner.
The methods of mining of this invention include method steps for the primary mining of coal in a room-and-pillar manner as well as method steps for the secondary mining of coal from pillars.
BRIEF DESCRIPTION OF THE DRAWINGS
The preferred embodiment of applicant's invention will now be described with reference to the drawings in which:
FIG. 1 is a top plan view of applicant's continuous mining apparatus;
FIG. 2 is a side elevational view of applicant's continuous mining apparatus;
FIG. 3 is a top plan view, partly in phantom, and showing the cutter assembly of applicant's continuous mining apparatus;
FIG. 4 is a side elevational view, partly in phantom, and taken along the line 4--4 of FIG. 3;
FIG. 5 is a side elevational view, partly in phantom, taken along the line 5--5 of FIG. 3;
FIG. 6 is an elevational view, partly in section, taken along the line 6--6 of FIG. 1;
FIG. 7 is a front elevational view of the continuous mining apparatus of this invention taken along the line 7--7 of FIG. 1;
FIG. 8 is a top schematic view of the conveyor assembly of applicant's continuous mining apparatus and showing the telescoping support frame;
FIG. 9 is a side schematic representation of the conveyor belt of the conveyor assembly of applicant's continuous mining apparatus showing the manner of support thereof;
FIG. 10 is a side elevational view showing the conveyor assembly of the continuous mining apparatus of applicant's invention in a collapsed position;
FIG. 11 is a side elevational view showing the conveyor assembly of the continuous mining apparatus of applicant's invention in an extended position;
FIG. 12 is an elevational view, partly in section, taken along the line 12--12 of FIG. 10;
FIG. 13 is a side schematic view of the conveyor belt and control cable of the conveyor assembly of the continuous mining apparatus of the invention and showing the manner of support thereof with the conveyor assembly in an extended position;
FIG. 14 is a side schematic view of the conveyor belt and control cable of the conveyor assembly of the continuous mining apparatus of the invention and showing the manner of support thereof with the conveyor assembly in a retracted or telescoped position;
FIG. 15 is a side elevational view, partly in phantom, and showing a modified embodiment of the conveyor assembly of the continuous mining apparatus of this invention;
FIG. 16 is a side elevational view, partly in phantom, and showing a further modified embodiment of the conveyor assembly of the continuous mining apparatus of this invention;
FIG. 17 is a side elevational view of the continuous miner of this invention operating with an auxiliary conveyor;
FIG. 18 is a top schematic view of a mine and showing one conventional method of the primary and secondary mining of coal in a room-and-pillar configuration;
FIG. 19 is a top schematic view of a mine and showing applicant's method of the primary and secondary mining of coal in a room-and-pillar configuration; and
FIG. 20 is a schematic view of a pillar and showing applicant's modified method of the secondary mining of coal.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment of the invention will now be described with reference initially to FIG. 1. The continuous mining apparatus of this invention is generally designated 10 in FIG. 1 and is made up of a cutter assembly 12, conveyor assembly 14 and a base assembly 16. For ease of description each of the various assemblies will now be described individually.
CUTTER ASSEMBLY
As best seen in FIGS. 1 and 3, the cutter assembly of the invention extends from the outermost end 18 of the continuous mining apparatus to the trunnions 20, 22 which are supported generally by the frame of the conveyor assembly 14 and which provide pivotal support for the cutter assembly 12. A generally U-shaped frame 24 is pivotally supported by trunnions 20, 22 and provides support for the longitudinal augers 26, 28 and the transverse auger 30. Longitudinal augers 26, 28 are driven by drive shafts 32, 34 which are, in turn, powered by motors 36, 38. The motors 36, 38 along with the associated drive apparatus are mounted on frame 24. Motors 36, 38 may be either electrically driven or hydraulically powered at the option of the user. If electrically driven, provision must be made for the supplying of an electrical source of power to the motors. If hydraulically powered, provision must be made for the placement of hydraulic lines at the respective motors.
Transverse auger 30 is powered by a pair of bevel gears 40, 42 which are turned by complementary bevel gears 44, 46 driven by motors 36, 38, respectively.
Provided at the respective ends of longitudinal augers 26, 28 are cutters 48, 50. Cutters 48, 50 are provided with carbide cutting surfaces 52, 54 which are adapted to be rotated into cutting engagement with a coal face or seam. It should be understood that when motors 36, 38 are energized longitudinal augers 26, 28 along with the associated cutters 48, 50 are caused to rotate. Similarly, transverse auger 30 is caused to rotate.
The cutter assembly of applicant's continuous mining apparatus is adapted to be thrust or crowded into the exposed coal face or seam at the working face of the mine in order to break up and chew coal into relatively small chunks at the exposed face. Once broken up by the rotating cutters 48, 50 the coal is accumulated in the bottom pan 56 of the cutter assembly where, after a sufficient accumulation of coal has developed, a flow of coal will proceed to the transverse auger 30. The function of the transverse auger 30 is to enhance the rearward movement of coal from the cutters 48, 50 to a location substantially adjacent the belt 58 of the conveyor assembly 14. As best seen in FIGS. 4 and 5, the bottom pan 56 takes an upward slope at 60 in order to cause the coal to be fed upward to the moving belt 58. Carbide cutting tips 62 are provided on the transverse auger 30 in order to further facilitate breaking up of the coal as it is conveyed to the moving belt 58.
A front view of the cutter assembly is shown in FIG. 7. As will be seen from FIG. 7 frame 24, the forward end of the cutter assembly is generally U-shaped and defines a general scoop configuration in order to provide for the pick-up and retention of coal at the face after cutting has been accomplished by means of the rotating cutters 48, 50.
As was previously indicated, the entire cutter assembly 12 is pivoted to the conveyor assembly 14 by means of trunnions 20, 22 which are provided at the forward end of the conveyor assembly. As best seen in FIG. 2, a pair of attitude adjusting cylinders 64 are provided on either side of the cutter assembly 12. One end of adjusting cylinder 64 is connected to the conveyor assembly 14 at flange 66. The other end of adjusting cylinder 64 is connected to frame 24 at pin 68. It should be appreciated, therefore, that actuation of adjusting cylinder 64 through the application of either hydraulic or air pressure will cause the entire cutter assembly 12 to rotate about the axis of trunnions 20, 22 thus providing for adjustment of the attitude of the cutter assembly 12 relative to the coal face. Such coal face is designated 70 in FIG. 2.
CONVEYOR ASSEMBLY
Attention will now be directed to FIGS. 1 and 6 where the conveyor assembly 14 of applicant's continuous mining apparatus will now be described.
Before proceeding with a detailed description of the conveyor assembly 14 it should be understood that one of the purposes and functions of the conveyor assembly is to transport coal from the cutter assembly 12 to the base assembly 16. Base assembly 16, as shown in FIG. 2 and as will be described in greater detail below, is adapted to be fixed in place in the mine during operation of the continuous mining apparatus. That is to say, once positioned as shown in FIG. 2, the base assembly 16 is adapted to remain stationary in the mine while the cutter assembly 12 is caused to move outwardly from the base assembly 16 into the coal face as is shown in FIG. 2. The purpose and function of the conveyor assembly 14 is to provide for a variable length conveyor belt between the cutter assembly 12 and the base assembly 16 while, at the same time, providing a means to crowd or move the cutter assembly 12 into the coal face.
Conveyor assembly 14 is supported by a plurality of telescoping box-like support elements 74, 76, 78 and 80, 82 84. Support elements 74, 80 are themselves secured to the base assembly 16 as best seen in FIGS. 1 and 2. In turn, the support elements 74, 80 provide rigid support for the telescoping inner members 76, 78 and 82, 84.
As best seen in FIG. 6, support elements 78, 84 are telescoped within the larger support elements 76, 82. Rollers 92, 94 are positioned within the support elements 76, 82 for the purpose of providing rolling support for the support elements 78, 84. Additional rollers are provided behind rollers 92, 94 (not shown) to provide for further support. In turn, support elements 76, 82 are slidably received within the larger support elements 74, 80. Rollers 96, 98 are provided within the support elements 74, 80 to provide sliding support for the elements 76, 82. Additional rollers (not shown) are provided within elements 74, 80 to support elements 76, 82.
It should thus be appreciated that the respective support elements 74, 76, 78 are slidably received within one another in a manner so as to provide for an extension or contraction of these elements relative to the base assembly 16. Similarly, the support elements 80, 82, 84 are slidably received within one another in order to provide for the expansion or contraction of these elements relative to the base assembly.
The largest of the support elements, i.e., 74, 80, are in turn, slidably supported by rollers 100, 102 which are affixed to the base assembly 16 and which provide for sliding support of the elements 74, 80 relative to the base assembly 16. Additional rollers (not shown) are provided for the elements 74, 80.
Each of the respective pairs of support elements 74, 80; 76, 82 and 78, 84 are provided with a belt supporting structure of the type shown in FIG. 12. FIG. 12 shows the belt supporting structure for the outermost support elements 78, 84 and which includes supporting blocks 132, 134 which are secured respectively to the upper surfaces of the support elements 78, 84 and a transverse support member 136. Rollers 138, 140, 142 are rotatably supported by a framework which includes member 144 secured to support member 136 and upwardly extending side members 146, 148. It should be appreciated as shown in phantom in FIG. 12 that the rollers 138, 140, 142 provide rolling support for the belt 58.
Each of the respective pairs of support elements is provided with a belt support structure of the type shown in FIG. 12. That is to say, each of the respective support elements 74, 80 and 76, 82 are provided with belt support structure of the type shown in FIG. 12. This may be seen from FIG. 6 wherein belt support structures 150, 152, 154 are generally shown. Belt support structure 150 generally corresponds to that shown in FIG. 12 and is associated with the support elements 78, 84. Belt support structure 152 is associated with the support elements 76, 82. Finally, belt support structure 154 is associated with the support elements 74, 80. The just mentioned belt support structures are also shown in FIG. 2 where it may be seen that the general level or height of belt 58 is caused to rise from a low point adjacent the cutter assembly 12 to a high point at the base assembly 16.
As will be seen from FIGS. 10, 11 and 12, the supporting blocks 132, 134 are generally elongated and extend along the upper surface of the respective support elements. As seen in FIG. 12, the supporting blocks 132, 134 are provided with an internal recess 156 which is of dovetail shape adapted to receive a complementary dovetail element 158 which is provided on the side members 146, 148. With the relationship of parts as shown in FIG. 12 it should be appreciated that the side members 146, 148 are free to slide with respect to the supporting blocks 132, 134 in order to provide for longitudinal adjustment of the belt support structures 150, 152, as the conveyor assembly 14 is moved either in a retracted or extended position.
As shown in FIG. 10 the conveyor assembly 14 is in a retracted position with the support element 84 telescoped within support element 82. In turn, support element 82 is telescoped within support element 80. As the support elements 84, 82 are caused to be telescoped within adjacent support elements it can be appreciated that the respective side members 146, 148 will be moved to the left of FIG. 10. A continuous telescoping action of the support elements will cause continued movement to the left of FIG. 10 of the side members 146, 148 until such time as the side members contact an adjacent support element. Further telescoping action of the support elements may continue with a sliding action taking place between the side members 146, 148 and the respective supporting blocks 132, 134.
At such time as the conveyor assembly 14 is placed in an extended position, movement of the support elements will progress to the right as shown in FIGS. 10 and 11. A movement to the right as shown in FIG. 11 will cause a similar movement to the right of the side members 146, 148 until such time as the chains 160 become taut. As will be evident from FIG. 11 each of the respective chains is attached, at one end, to a side member 148 and at the other end to a support element. As the respective support elements are extended a point in time will be reached when the chains 160 become taut causing an associated side member 148 to become fixed relative to an adjacent support element. Continued outward movement of the support elements will cause a sliding motion to take place between the side members 146, 148 and the associated supporting blocks 132, 134.
The purpose and function of the dovetail interconnection between the belt support structures and the associated supporting blocks is to provide means to longitudinally adjust the belt supporting structures regardless of the degree of extension or retraction of the conveyor assembly 14. That is to say, as the conveyor assembly 14 is extended (as shown in FIG. 11) the belt support structures become more widely separated in order to provide for uniform support of the belt. Conversely, when the conveyor assembly 14 is retracted or telescoped (as shown in FIG. 10) the belt support structures come together but in a uniform manner so as to provide for a uniform or even support of the belt.
Turning to FIG. 1 it will be seen that the end of belt 58 nearest the cutter assembly 12 is supported by means of roller 90. Roller 90 is, in turn, supported by an internal roller shaft 91 which is itself supported by longitudinal supports 116, 118 (FIG. 6). Supports 116, 118 are secured to the support elements 78, 84 by means of pins 108, 114. It should thus be understood that the longitudinal supports 115, 118 extend generally parallel to the support elements 78, 84 and are affixed thereto by means of pins 108, 114.
Similarly, longitudinal supports 120, 122 are provided generally parallel to support elements 76, 82 and are affixed thereto by means of pins 106, 112.
In the same manner longitudinal supports 124, 126 extend generally parallel to support elements 74, 80 and are affixed thereto by means of pins 104, 110.
As best seen in FIG. 6, the longitudinal supports 116, 118, 120, 122, 124 and 126 are arranged in pairs one above the other so as to be capable of being nested when the conveyor assembly 14 is contracted or telescoped together. Additional support for the nested longitudinal supports is provided by lower supports 128, 130 (FIG. 6) which are affixed to the base assembly 16.
The purpose and function of the longitudinal supports 116, 118, 120, 122, 124 and 126 is to support a plurality of rollers over which the conveyor belt 58 is adapted to pass in order to define an adjustable length conveyor. The threading conveyor assembly is shown schematically in FIG. 9.
Referring to FIG. 9, it may be seen that the longitudinal support 116 (and the complementary support 118 not shown) support roller 90 with its associated roller shaft 91. In addition, longitudinal support 116 (and its complementary support 118) support roller 162.
Longitudinal support 120 (and its complementary support 122) support rollers 164 and 166.
Longitudinal support 124 (and its complementary support 126) support rollers 168 and 170.
Finally, lower support 128 (and its complementary support 130) support roller 172.
It should be appreciated from a study of FIG. 9 that the conveyor assembly 14 which is shown extended in the schematic view of FIG. 9 defines a variable length conveyor which utilizes an essentially fixed length conveyor belt 58. The nested longitudinal supports 116, 120, 124 and the complementary longitudinal supports 118, 122, 126 provide for an adjustable length conveyor which may be set to provide for any measurement of length from the fully telescoped or fully collapsed position of the conveyor assembly shown schematically in FIG. 14 to the fully extended position shown schematically in FIGS. 9 and 13.
Referring to FIG. 13, it will be seen that conveyor belt 58 is powered by drive 174 which is fixed to the base assembly 16. In addition to drive 174, idler rolls 176, 178, 180 and 182 are provided in the base assembly 16 in order to complete threading of the conveyor belt 58 throughout the assembly. It should thus be appreciated from a study of FIG. 13 that when powered the drive 174 causes the conveyor belt 58 to move in the arrow direction shown (from right to left in FIG. 13) in order to transfer coal from the cutter assembly (adjacent the roller 90) to the rear of base assembly 16 where it is thereafter conveyed to additional conveying apparatus provided in the mine as shown in FIG. 17.
As has been previously noted, the length of the conveyor belt 58 is essentially fixed when threaded into the conveyor assembly and base assembly in the manner shown schematically in FIG. 13. Because of the arrangement of the several elements of the conveyor assembly and base assembly the total length of the conveyor belt 58 will not vary regardless of the degree of retraction or expansion of the conveyor assembly.
Turning once again to FIG. 13, attention will now be directed to the graphical representation of the wire rope mechanism for telescoping and expanding the conveyor assembly 14 of the invention.
As seen in FIG. 13, a pair of drive means 186, 188 are housed within the base assembly 16. The drive means are adapted to rotate in selective clockwise or counterclockwise directions as will be described below. A cable 190 is wound about drive means 186, attached to support element 78 at 191 and is threaded through a plurality of rollers supported by the several longitudinal supports 116, 120, 124 where it is thereafter wound about drive means 188. Longitudinal support 116 provides support for cable rollers 193 and 194. Longitudinal support 120 provides support for cable rollers 196, 198. Longitudinal support 124 provides support for cable rollers 200, 202. Finally base assembly 16 provides support for cable roller 204.
The cable rollers 193, 194, 196, 198, 200, 202 and 204 and attachment point 191 are shown schematically in FIG. 13 as being associated with the longitudinal supports 116, 120, 124. This is for ease of description to show the interrelationship of the conveyor belt 58 and the cable drive 190. In actuality, however, the respective cable rollers 193, 194, 196, 198, 200, 202, 204 and attachment point 191 are carried by the respective support elements as is shown more particularly in FIG. 6. Thus the cable rollers 193, 194 and attachment point 191 are associated with the support element 78 and are carried by the wall of the support element 78 in the space defined between the support element 78 and the support element 76. Cable roller 193 is shown in FIG. 6. Cable roller 194 is not shown in FIG. 6 but it should be understood that it is located immediately behind the cable roller 193 and is supported by the support element 78 in the same manner as the support provided for the cable roller 193. The cable roller 196 is attached to and supported by the wall of the support element 76 in the space between the support element 78 and support element 76. The cable roller 198 is not shown in FIG. 6 but it should be understood that it is located immediately behind the cable roller 196 and is supported by the support element 76 in the same manner as the support provided the cable roller 196.
Cable roller 200, in FIG. 6, is supported by the support element 74 and is located between the bottom walls of the support element 76 and the support element 74. Cable roller 202 is not shown in FIG. 6 but it should be understood that it is located immediately behind cable roller 200 and is supported in a manner similar to cable roller 200.
Finally, cable roller 204 is positioned, in FIG. 6, beneath support element 74 and is supported by the base assembly 16.
It should be understood that cable rollers corresponding to those designated 193, 194, 196, 198, 200, 202 and 204 are provided in association with the support elements 80, 82 and 84. These cable rollers are designated 193', 196', 200' and 204' in FIG. 6.
Referring once again to FIG. 13, it should be understood that the conveyor assembly 14 as shown in FIG. 13 is in a fully extended position. If it is desired to shorten the length of the conveyor assembly, this is accomplished by a counterclockwise driving of drive means 186 and counterclockwise driving of drive means 188. Counterclockwise driving of the drive means 186 causes the cable 190 to be taken up in the upper portion of the conveyor assembly 14 (as viewed in FIG. 13). At the same time drive means 188 is permitted to rotate in a counterclockwise direction so as to pay out cable from drive 188. This, in turn, causes the support elements to become nested or collapsed as shown in FIG. 14.
Should it be desired to extend or open the conveyor assembly 14 from the collapsed position shown in FIG. 14, this may be accomplished by causing the drive means 188 to be driven in a clockwise direction so as to take up cable 190 in the lower portion of the conveyor assembly. At the same time drive means 186 is permitted to rotate in a clockwise direction so as to pay out cable from drive 186.
It may thus be seen that the cable drive mechanism of this invention provides for positive positioning of the conveyor asssemby 14 into a variable length conveyor having a minimum longitudinal length as shown in FIG. 14 and a maximum longitudinal length as shown in FIG. 13.
BASE ASSEMBLY
Attention will now be directed to FIGS. 1 and 2 where the base assembly 16 of this invention will now be described.
As best seen in FIG. 2, the base assembly 16 includes a main body 206, drive tracks 208 and a plurality of hydraulic cylinders 210, 212.
Main body 206 of base assembly 16 provides a convenient housing for internal elements of the apparatus of this invention including engine drive means for tracks 218, cable drive means 186, 188 (shown schematically in FIG. 13), conveyor belt drive means 174 (shown schematically in FIG. 13), and associated and additional control apparatus.
Drive tracks 208 are of conventional design adapted to be powered by internal engine means and, when activated, may propel the base assembly either forward, backward, or in a turning direction as by counterrotation of the tracks.
With reference to FIGS. 1 and 2 it will be noted that four generally vertical hydraulic cylinders 210 are provided at approximately the corners of the base assembly 16. Hydraulic cylinders 210 have two principal functions. First, the cylinders provide for roof support at the base assembly 16 thus protecting the operator and the base assembly from damage due to a cave-in of the roof. Second, hydraulic cylinders 210 function to position the base assembly 16 firmly in place during a cutting operation. Hydraulic cylinders 210 thus function to wedge the base assembly 16 in place as the cutter assembly 12 is advanced or crowded into the coal face.
Generally vertically disposed hydraulic cylinders 212 are also provided at corner extensions of the base assembly 16 as shown in FIGS. 1 and 2. The purpose and function of cylinders 212 is to adjust the height of the base assembly 16 in the mine. In the position shown in FIG. 2 the base assembly 16 is resting on the mine floor with the tracks 208 in contact with the floor. It can be appreciated, however, that by extending hydraulic cylinders 212 and retracting hydraulic cylinders 210 the entire base assembly 16 may be lifted from the floor to various heights
Also associated with the base assembly 16 are a plurality of belt support structures 214 which provide support for the drive belt 58 as it passes over the base assembly 16. An end roller 182 is supported by the base assembly 16 and defines the point where the conveyor belt 58 is routed back into the base assembly 16 to the internally disposed drive 174 (shown schematically in FIG. 13).
As shown in FIG. 2 the base assembly 16 is provided with an electrical cable 216 which extends from the base assembly 16 to the cutter assembly 12. Electrical cable 216 is adapted to provide electrical power to the motor 38. A similar electrical cable 216' (FIG. 1) is provided at the opposite side of the base assembly 16 for the purpose of supplying power to the motor 36.
In addition to supplying power to the cutter assembly 12 the base assembly 16 also provides for ventilation means at the face of the mine. Such ventilation means is shown schematically at 220 in FIG. 1 and includes exhaust fans (not shown) mounted in the base assembly 16 which are adapted to draw air from the face of the mine where the cutting operation is taking place and conduct the air through the interior of the telescoped supporting elements 74, 76, 78 and 80, 82, 84 where it is then conveniently transmitted through the base assembly.
OPERATION
The operation of the continuous mining apparatus of this invention will now be described with reference principally to FIG. 2. Assume initially that it is desired to make a cut into the coal face 70. The continuous mining apparatus including the cutter assembly 12, conveyor assembly 14 and base assembly 16 is caused to be positioned at the coal face 70 with the conveyor assembly in a collapsed or retracted configuration. That is to say, the conveyor assembly 14 of the continuous mining apparatus is in a minimum length condition.
Once positioned in place with the conveyor assembly 14 collapsed, the hydraulic cylinders 210, 212 are then adjusted in order to fix the base assembly 16 in place at the desired height. It should be appreciated that all times during the cutting operation to be described the base assembly 16 is fixed in place.
The operator of the continuous mining apparatus is positioned either adjacent or behind the base assembly 16. The cutting operation begins as power is directed to the motors 36, 38 causing the cutters 48, 50 to rotate. In addition to supplying a source of electrical energy for the motors 36, 38 the operator causes the conveyor belt drive means 174 to become operating as well as the cable drives 186, 188. It should be understood that with the belt drive 174 in operation the upper surface of the conveyor belt 58 is caused to move from right to left as shown in FIG. 2.
Activation of the cable drive means 186, 188 in the appropriate rotational mode will cause the fully collapsed conveyor assembly 14 to become elongated. This action not only causes the longitudinal length of the conveyor assembly 15 to increase but also causes the cutter assembly 12 to be advanced or crowded into the coal face 70. With an end thrust thus being provided at the cutter assembly, the cutters 48, 50 are driven into the coal face causing the coal at the face to become disintegrated where it is collected at the cutter assembly 12 and thereafter conveyed to the base assembly 16. Continued operation of the cable drive mechanism will cause the cutter assembly 12 to dig deeper and deeper into the coal face until such time as the continuous mining apparatus is shut down or, alternately, until the conveyor assembly 14 reaches a point of maximum extension. Once the conveyor assembly 14 is extended to a maximum degree no further end thrust may be applied to the cutter assembly 12. It is thus not possible to continue the cutting operation until the base assembly 16 has been repositioned.
While the length of the several components of the invention including the cutter assembly 12, conveyor assembly 14 and base assembly 16 may vary depending upon design considerations, it is projected that the cutter assembly 12, in the preferred embodiment, may be extended outwardly from its initial position at the coal face 70 at the start of the cutting operation to approximately 80-100 feet from its initial position with the conveyor assembly 14 completely extended. That is to say, the difference between the collapsed length of the conveyor assembly is approximately 80-100 feet in the preferred embodiment. This enables a single cut of approximately 80-100 feet to be made in the face of the coal by the cutter assembly 12.
As shown in FIG. 2, the cut 224 being made in the face 70 is in the lower portion of the face. In actuality, however, it may be desirable to make the initial cut in the face at the upper portion of the face near the roof. An upper cut may be made by causing the entire base assembly 16 to be elevated through extension of the hydraulic cylinders 212 and retraction of the hydraulic cylinders 210. Once elevated the entire continuous mining apparatus of the invention including the cutter assembly 12 will be caused to be elevated thus positioning the cutters 48, 50 in the upper portion of the mine. In the preferred embodiment the vertical height of the cut 224 made by the cutter assembly 12 is approximately five feet. Thus, should the vertical height of the coal face 70 be approximately 10 feet, two cuts may be conveniently made in the coal face (an upper cut and a lower cut) in order to remove all of the coal at the face.
Once the coal has been conveyed from the cutter assembly 12 to the base assembly 16 it, thereafter, is conveyed to the main entry where it is then taken from the mine. Suitable conveyors may be used for this purpose such as conveyor 226 shown in FIG. 17.
MODIFICATIONS OF THE INVENTION
Two modified forms of the drive mechanism for the conveyor assembly 14 are shown in FIGS. 15 and 16.
With reference to FIG. 15, a conveyor assembly designated 14' is made up of telescoping support elements 80', 82' and 84'. These telescoping elements extend from the base assembly 16'. In lieu of the cable drive mechanism shown schematically in FIG. 13, the interengaging support elements of FIG. 15 are adjusted by means of roller chains 230, 232 and 234. Roller chain 230 provides for relative movement of support element 80' with respect to base assembly 16' by means of the drive flange 236 which is secured to the support element 80'. Similarly, movement of support element 82' with respect to support element 80' is accomplished by means of roller chain 232 which is secured to drive flange 238 which extends from support element 82'. Finally, movement of support element 84' relative to support element 82' is achieved by means of roller chain 234 which is adapted to move drive flange 240 either to the right or to the left of FIG. 14. The several roller chains 230, 232, 234 of FIG. 15 may be driven by any convenient drive means including, but not limited to, electric motors or hydraulic motors.
A further modified embodiment of the drive means for the conveyor assembly 14 is shown in FIG. 16. In FIG. 16 the conveyor assembly 14' is shown as comprising the support elements 80", 82" and 84". Hydraulic cylinder 244 is attached to the base assembly 16" and provides for movement of the support element 80" with respect to base assembly 16". Hydraulic cylinder 246 is attached to support element 80" and provides for relative movement of the support element 82" relative to support element 80". Finally, hydraulic cylinder 248 is secured to support element 82" and provides for relative movement of the support element 84" relative to support element 82".
The various hydraulic cylinders 244, 246, 248 of FIG. 16 are adapted to be powered by any source of pressurized fluid as may be convenient.
METHOD
Applicant's method of mining coal from seams will now be described.
Referring first to FIG. 18 there is shown therein a schematic representation of a plan view of a coal mine and showing the conventional manner of removal of coal therefrom. The mine of FIG. 18 includes a number of main passageways or main entries 256 and a plurality of crosscuts 258. The crosscuts 258 generally extend perpendicular to the main entries 256. The several main entries and crosscuts define a plurality of pillars of coal 260. Depending upon applicable laws, pillars 260 may have various dimensions. A 50 by 50 foot dimension is a typical minimum pillar size in many states.
The primary mining of coal from a seam involves, therefore, the removal of coal by driving a series of "rooms" into the coal thereby defining a plurality of pillars which are left standing to support the roof until the area is mined out in secondary mining. FIG. 18 represents, therefore, a room-and-pillar approach to primary mining of coal. The process of secondary mining a mine involves the removal of a part or all of the pillars permitting the roof to cave in. Removal of the pillars is systematic in order to provide for protection of both miners and their equipment.
In a typical mine the pillars 260 of FIG. 18 will have a square dimension of approximately 50 feet on a side. The distance between the pillars, i.e., the width of the crosscut and the width of the main entry or passageway is approximately 20 feet.
A continuous miner operating today can remove in a single cutting operation a volume of coal having dimensions of approximately 10 feet wide, 20 feet deep and 5 feet high. The width dimension of the miner (approximately 10 feet) is governed by the width of the cutter of the miner. The length dimension of the cut made by the miner is governed by applicable safety regulations. As a miner makes a cut into a face of coal the newly exposed roof over the working miner is unsupported. Applicable safety regulations usually provide that the operator of the miner may not advance into the coal face more than a few feet (usually four or five feet) from the last mine roof support (bolt or post). Faced, therefore, with the limitation that the operator of a continuous miner cannot extend himself more than four or five feet from the last mine roof support it is not possible for a continuous miner to extend into a face of coal for more than approximately 20 feet. Having done so the miner is then withdrawn and mine roof control measures are then installed. Once installed the miner may re-enter the area of the cut and make a second cut for approximately an additional 20 feet.
The process of mining using a conventional continuous miner is thus one of stop and go. Once a cut of approximately 20 feet is made in the coal face it is necessary to withdraw the miner for bolting or other roof control measures During, the interim time when mine roof control procedures are being implemented the miner may proceed to another portion of the mine and make a new cut.
Referring once again to FIG. 18, a continuous miner may operate to make cuts 262, 264 before being removed to permit roof control procedures to be installed. While such roof control measures are being taken the continuous miner may make cuts 266 and 268. With the completion of roof control procedures at cuts 262 and 264 the continuous miner may re-enter the passageway 256 and make additional cuts 270, 272. The continuous miner is then withdrawn from the area of cuts 270, 272 to permit roof control procedures to be installed and may be transported back to the vicinity of cuts 266 and 268 in order to make further cuts 274 and 275. This procedure is repeated time and time again in order to define new pillars of coal in removing coal from extensions of the main entries 256 and the crosscuts 258.
As best can be seen from a study of FIG. 18, present day coal methods in utilizing continuous miners are largely governed by safety considerations with respect to the installation of mine roof control measures. Much of the time spent during an operating shift with the continuous miner involves the movement or transportation of the miner from cut to cut as roof control procedures are implemented In fact, it is not unusual for a continuous miner to have as much or more down time in transportation or the like as time spent mining coal.
The process just described involving the making of cuts 262, 264, 266, 268, 270, 272, etc. is one conventional method of the primary mining of coal called the room-and-pillar method.
Secondary mining of coal involves the removal of pillars 260 with the subsequent caving in of the mine roof. Pillar removal in secondary mining is, by its nature, systematic so as not to endanger lives or threaten equipment.
For illustration purposes reference is made to the secondary mining of coal from the mine shown schematically in FIG. 18.
Assume that it is desired to remove the bottommost pillars 260 in FIG. 18. To do this a typical mine roof plan will permit the continuous miner to make an initial cut 276 in the pillar 260 as shown. Once made the continuous miner is removed and a cut 278 is made in an adjacent pillar. Having completed cut 278 the continuous miner is again moved and a third cut 280 is made in a still adjacent pillar. After each of the respective cuts is made mine roof control procedures such as bolting are implemented. With the completion of the third cut 280 the continuous miner returns to the original pillar and makes a second cut in that pillar designated as cut 282. The miner is then removed and proceeds to the adjacent pillar where a cut 284 is made. After completion of cut 284 the miner is removed to the next adjacent pillar and a cut 286 is made. After each of the cuts has been made mine roof control procedures such as bolting are implemented.
In the final stage of secondary mining the miner will return to the end pillar and take diagonal cuts designated 288, 290. Similar diagonal cuts are taken in the adjacent pillar at 292, 294. Finally diagonal cuts 296, 298 are made in the third pillar.
The operation just described is typical of present day mining methods found in approved roof control plans.
FIG. 18 illustrates, therefore, the degree of movement experienced by a continuous miner whether the operation involves primary or secondary mining of coal. As indicated above, the extensive movement and transportation of the continuous miner from place to place is necessitated by the safety requirement that the operator of the miner must not be excessively exposed to an unsupported roof.
Applicant's method of mining coal eliminates much of the movement of the continuous miner. Applicant's method involves the use of an extensible cutter assembly extending from a stationary base assembly which permits the cutter assembly to reach out over longer distances in the mining of coal without exposing the operator to an unsupported roof.
With brief reference to FIG. 2 it will be remembered that the apparatus of this invention is comprised of three basic elements, i.e., the cutter assembly 12, conveyor assembly 14 and base assembly 16. The base assembly is fixed firmly in place by means of hydraulic jacks 210, 212. During a cutting operation the cutter assembly 12 is caused to be crowded into the coal face by means of the extensible conveyor assembly 14. The operator stationed at the base assembly 16 is, at all times, protected against an unsupported roof in two ways. First, the base assembly 16 is positioned in a supported area of the mine, that is to say in an area of the mine where roof control procedures have been implemented. Second, the hydraulic jacks 210 provide for localized roof support immediately over the base assembly 16.
As previously described, applicant's apparatus permits the cutter assembly 12 to be thrust forward approximately 80-100 feet without requiring the operator to leave the base assembly 16. Thus a cut on the order of magnitude of 80-100 feet may be made in a coal face in a manner so as to expose no miner to an unsupported roof.
The versatility of applicant's apparatus in practicing the method of this invention may be seen from FIG. 19. FIG. 19, like FIG. 18, illustrates a cross-section of a typical mine in which a plurality of pillars 300 have been defined by a plurality of entries 302 and a plurality of crosscuts 304. Assuming that it is desired to extend the mine in an upward direction of FIG. 19 applicant's apparatus and method provide for the making of single cuts 306 and 307 at one time. Remembering that the pillar dimensions in the example given with respect to FIG. 18 and FIG. 19 are approximately 50 by 50 feet and that the crosscut widths are approximately 20 feet, it will be seen that the longitudinal length of the cuts 306 and 307 is approximately 70 feet. Bearing in mind that applicant's apparatus is capable of making continuous cuts of 80-100 feet it may be seen that the 70 foot cuts 306 and 307 of FIG. 19 are readily within the capability of the miner of this invention. Having made the cuts 306 and 307 the miner may then be turned 90 degrees where additional cuts 308, 309 are made. After completion of cuts 308 and 309 still further cuts 310, 311 may then be made.
Of course it should be appreciated that after cuts 306, 307 are made, roof bolting procedures will be implemented while the cuts 308, 309 are being made. Similarly, while cuts 310, 211 are being made, roof bolting procedures will be implemented in the area of cuts 308, 309. After roof bolting has been completed the continuous miner of this invention may then be moved into position in order to make the next cuts 312, 313. Thereafter, cuts 314, 315 and 316, 317 may be made.
It can be appreciated from a study of FIG. 19 that the extensive reach of applicant's apparatus makes it possible to readily conduct primary mining of coal in a mine. Since the extensible cutter is able to reach out for fairly large distances in excess of the dimensions of the coal pillars and passageways, it can be seen that applicant's apparatus may be conveniently positioned to make cuts in the entryways and crosscuts without significant movement of the miner. The geometric pattern illustrated in FIG. 19 may be repeated as often as is necessary in order to provide for the primary mining of coal in the manner illustrated.
As to the secondary mining of coal, applicant's apparatus and method provides significant advantages not heretofore found. With further reference to FIG. 19 let us assume that it is desired to remove a part or all of the lower or bottom pillars 300 illustrated in FIG. 19. Assuming that it is desired to remove the lower right-hand pillar of FIG. 19 the continuous miner of this invention may be advantageously positioned at 320 where a plurality of continuous cuts 322, 324, 326 and 328 may be made in the pillar to remove substantially all of the pillar. During the second mining operation just described the miner, while positioned at 320, receives the roof support provided by adjacent pillars. In addition, timbers or other auxiliary supports may be used. The necessity, however, of making small cuts in the pillar with subsequent roof bolting is eliminated as the cutter assembly of applicant's apparatus is capable of being extended through an entire pillar in a single reach.
If it is not desired to remove an entire pillar in secondary mining, a procedure such as that shown schematically in FIG. 20 may be employed. In FIG. 20 there is shown schematically a pillar 330 in which a plurality of auger-like cuts 332 have been made through the pillar leaving some of the pillar in place.
METHOD OF PRIMARY MINING
Applicant's method of primary mining of underground coal consists of the following method steps:
(a) providing a continuous miner having a cutter assembly, conveyor assembly and base assembly. These elements are shown as 12, 14, 16 respectively in FIG. 1. The cutter assembly 12 is adapted to be projected outwardly from the fixed base assembly 16 (FIG. 2) in a manner so as to be crowded or forced into the face of a coal seam 70. The conveyor assembly 14, which is positioned intermediate the cutter assembly 12 and the base assembly 16, provides an end thrust on the cutter assembly 12 forcing the cutter assembly 12 into the coal face while, at the same time, defining an extensible or variable length conveyor means between the cutter assembly and the fixed base in order to transport coal from the cutter assembly to the fixed base.
(b) positioning the base assembly of the continuous miner (with the conveyor assembly in a collapsed condition such as shown in FIG. 14) at a fixed point in an area of the mine where there is roof support. The base assembly 16 (FIG. 2) which includes hydraulic cylinder 210 may be positioned in a manner so that the hydraulic cylinders 210 provide for roof support or, alternately, roof support means (such as bolts) may be provided in the roof itself.
(c) causing the cutter assembly 12 to be projected outwardly from the fixed base assembly 16 into the coal face with the variable length conveyor assembly 14 being positioned intermediate the cutter assembly 12 and the fixed base assembly 16.
(d) causing the cutter assembly 12 to travel away from the fixed base assembly 16 a distance equal to the dimension of the pillar being formed and the width of the passageway or crosscut adajcent the pillar being formed to make a first cut. Referring to FIG. 19 it will be seen that the length of the cut 306 is equal to the length of the pillar 300 and the width of the adjacent passageway which will be formed by the cuts 316, 317. In the example given above a pillar formed in a room-and-pillar manner of coal extraction may typically have a square dimension of 50 feet on a side. The adjacent passageways will typically have widths of approximately 20 feet. Thus, with the example just given, the cut 306 of FIG. 19 has a lengthwise dimension of approximately 70 feet.
(e) causing the cutter assembly to make additional cuts parallel to the first cut to remove all of the coal from the passageway being formed. Such additional cuts (along with the first cut) define cuts 306, 306 in FIG. 19.
(f) rotating the continuous miner approximately 90 degrees and causing additional passageways to be formed. Reference is made, in this regard, to cuts 308, 309 and 310, 311 in FIG. 19. While the additional passageways are being formed roof control procedures are undertaken with respect to the passageway formed by cuts 306, 307 and subsequently formed passageways.
(g) At such time as the three intersecting passageways are formed by the continuous miner (passageways defined by cuts 306, 307; cuts 308, 309; and cuts 310, 311) the continuous miner is then moved into the passageway formed by cuts 306, 307 to a position in order to make cuts 312, 313 where the entire process is then repeated. At each fixed location of the continuous miner three intersecting passageways are formed. As a consequence a plurality of pillars defined by intersecting main passageways and crosscuts are defined by applicant's method with a minimum of transportation of the continuous miner.
METHOD OF SECONDARY MINING OF COAL
Applicant's method for the secondary mining of coal will now be described with reference to FIG. 19.
As was indicated above, the secondary mining of coal involves the removal of coal from pillars in such a manner that the pillar is either totally or partially destroyed. Applicant's method involves the following steps:
(a) providing a continuous miner having a cutter assembly, conveyor assembly and base assembly as shown in FIGS. 1 and 2;
(b) stationing the base assembly of the continuous miner at a point adjacent the pillar to be removed. Such a point is shown at 320 in FIG. 19 and may, if desired, be in a portion of the mine having roof support measures installed;
(c) extending the cutter assembly away from the fixed base assembly a distance sufficient to permit the cutter assembly to extend completely through the pillar to be removed in order to make a single continuous cut through the entire pillar;
(d) repositioning the continuous miner in order to make additional cuts through the pillar thereby to remove a portion or all of the pillar.
As shown in FIG. 20 applicant's method for the secondary mining of coal may be used to remove coal in an auger-like fashion from pillars such as shown by cuts 332 in pillar 330. The upper cuts as shown in FIG. 20 are made by causing the base assembly 16 to be raised off of the floor of the mine thus permitting the cutter assembly 12 and the conveyor assembly 14 to be raised in a position to contact the coal face near the roof of the mine.
The ability to raise and lower the base assembly 16 through the use of hydraulic jacks (as shown in FIG. 2) not only permits applicant's method to be used for the secondary mining of coal in the manner shown in FIG. 20 but also gives flexibility in the primary mining of coal as it is possible to position the cutter assembly to remove individual layers of coal from the coal seam as desired. For example, it is possible to position the base assembly 16 (and, consequently, the cutter assembly 12 and conveyor assembly 14) relative to the mine face 70 (FIG. 2) in a manner to permit the removal of higher grades of coal from a seam in a single cutting operation while removing lower grades of coal in subsequent cutting operations. | A variable length conveyor assembly for use in the continuous underground mining of coal. The conveyor assembly comprises a base from which are adapted to extend a plurality of telescoping support elements. The support elements carry belt supporting members at the upper surfaces thereof and a plurality of longitudinal supports at the side surfaces thereof. The longitudinal supports, in turn, carry a plurality of rollers. An endless belt is supported by the belt supporting members and the rollers. Drive elements are located in the base for the endless belt. Cable rollers are associated with the support elements for purposes of receiving a control cable which is threaded through the cable rollers. Cable drive elements are positioned in the base which are adapted to move the control cable in a manner to selectively expand and contract the conveyor assembly. In alternate embodiments of the invention, the telescoping support elements are moved inwardly and outwardly by hydraulic rams or, alternately, chain drives. | 4 |
This application is filed within one year of, and claims priority to Provisional Application Ser. No. 60/449,442, filed Feb. 2, 2003.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to Emitter Locating Systems and, more specifically, to a Real-time Emitter Locating System and Method
2. Description of Related Art
Emitter Location (EL) Systems are used to locate the position of emitting radio transmitters. Presently in the industry today, finding the location of a radio transmitter involves triangulation methods using at least three radio Direction Finding (DF) “Sets”. Inherently though, the DF Sets that comprise EL Systems produce uncertainties in their measurements due to several factors which will be described later. The invention of this disclosure provides a far more accurate method of operating EL Systems than is presently done today.
As mentioned, present day EL Systems are comprised of multiple radio Direction Finding (DF) Sets which can either be fixed in location, or mobile on a vehicle, ship, aircraft, etc. The invention of this disclosure especially relates to EL Systems employing at least one mobile DF Set. In fact, with the use of the technique and method of this patent, only a single mobile DF Set is required in an EL System. To understand how uncertainties in the DF Set measurements are reduced with this invention, the background of direction finding operations needs to covered.
The basic components of a DF Set are: (1) a DF antenna array; and (2) a DF receiver/processor (hereafter referred to simply as “DF receiver”). The basic components of an EL System are: (1) at least one DF Set; (2) some device to interpret the streaming Line-Of-Bearing (LOB) data sets from the DF Set; (3) some sensor device to determine the DF Set's location; and (4) some sensor device to output the DF Set's orientation relative to true North.
The major sources of measurement errors in real-world DF Sets are: (1) uncertainties from the DF antenna array due to frequency dependent variations; and (2) received signal reflections (also known as multi-path).
Typically in a DF Set, a device is attached to the output that collects, interprets, and plots the line-of-bearing (LOB) data. This device is typically a computer which then displays the LOB's on some sort of map display. The LOBs that are displayed will vary from measurement to measurement depending on the aforementioned uncertainties. Most often in the industry today though, the DF Sets simply take the collected LOB data sets and average them to produce a best guess as to the true LOB to the transmitter. But as mentioned, the resulting LOB invariably has some level of error, which translates to errors in overall determination of the transmitter's location.
Another problem with present-day DF Sets is that the calculation of the transmitter's location is done by a batch process. That is, the output is calculated by taking every single previous measurement and doing an analysis on the entire aggregate set of data. This is a slow process and cannot be done in real time with large sets of data.
The invention described in this disclosure uses an improved method and technique to collect data from one or multiple DF Sets, and then to intelligently process that data in real time so that overall measurement uncertainties are reduced. Thus the transmitter's position plotted on a map will be more accurate. It should be reiterated that with the method and technique of this invention, it is possible to determine, and continuously plot on a map, the location of a transmitter by using only a single DF Set. This fact makes this invention further unique.
In conclusion, insofar as the inventor is aware, no invention formerly developed provides this unique application of methods to significantly reduce EL system measurement uncertainties.
SUMMARY OF THE INVENTION
In light of the aforementioned problems associated with the prior devices and methods, it is an object of the present invention to provide a Real-time Emitter Locating System and Method. The preferred system should provide a technique for taking in data sets (lines of bearing) from DF receivers and characterizing those signals with their respective probabilities of error. Then using a unique method, the preferred system can apply a recursive processing technique to this continuous stream of data, displaying transmitter positions with significantly less uncertainty. Furthermore, the preferred system must be able to perform these functions in real-time. It is a further object that this system is capable of being fully automated which would reduce the processing time and reduce the necessity of human intervention. It is still even further an object that an alternative embodiment of the present invention is to feasibly remote control the system over a network and collect and combine the same information from several DF Sets. In this way, a far more efficient EL System can be achieved in which the emitter's position can be determined more quickly from a centralized command facility. This combination of data filtering and data collection techniques significantly reduces measurement uncertainties and enhances the accuracy of EL systems.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and features of the present invention, which are believed to be novel, are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation, together with further objects and advantages, may best be understood by reference to the following description, taken in connection with the accompanying drawings, of which:
FIG. 1 is a drawing of a typical DF Set;
FIG. 2 is a drawing of the configuration of an EL System when employing the method of this invention;
FIG. 3 is a drawing of how emitter locating is presently done today with three or more DF Sets;
FIG. 4 is a drawing of the technique of this invention for collecting data;
FIG. 5 is a flow chart depicting the prior art DF method for locating a transmitter;
FIGS. 6A and 6B depicts the graphical approach employed by the present invention to determine a transmitter's position point; and
FIG. 7 is a flow chart depicting the real-time DF method for locating a transmitter of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description is provided to enable any person skilled in the art to make and use the invention and sets forth the best modes contemplated by the inventor of carrying out his invention. Various modifications, however, will remain readily apparent to those skilled in the art, since the generic principles of the present invention have been defined herein specifically to provide a Real-time Emitter Locating System and Method.
The present invention can best be understood by initial consideration of FIG. 1 . FIG. 1 is a drawing of a typical DF Set 10 . A DF Set 10 is comprised of a DF antenna 16 which is connected to a DF receiver 18 . The DF receiver then outputs LOB data 20 . The output LOB measurements are either raw data, or averaged data.
FIG. 2 is a drawing of the configuration of an EL System when employing the method of this invention. A single DF Set has its output LOB's and quality number data sent to a computer which runs the method of this invention. Other data from a GPS sensor and a Compass are also used. An EL System is comprised of a DF Set which outputs its LOB data to a computer device 26 . The computer also gets DF Set position data 24 from a positioning device 22 (which is often a GPS sensor), as well as DF Set orientation data 25 from a compass device 23 .
The computer 26 provides the following functions for the EL System: (1) Algorithms on the LOB data sets to reduce measurement uncertainties; (2) DF receiver control; (3) Mapping and LOB histogram displays; (4) Antenna calibration tables; (5) Networking capabilities; and (6) Integrated triangulation functions with other mobile/fixed DF Sets.
It should be reiterated and understood that present-day DF Sets contain inherent errors in their measurements, which translates to errors in the reported positions of transmitters in EL Systems. Averaging of the DF Set LOB data sets provides a very marginal approach to error correction. In summary, the disadvantages with this prior system and process are that:
(a) it is still subject to constant inherent uncertainties;
(b) the averaging methods typically used require full matrix multiplications of the LOB data-sets, which slows the computing process of determining a result;
(c) the uncertainties in individual DF Set measurements further create errors in multiple DF Set triangulation calculations.
What is needed therefore in order to fully optimize these EL systems is (1) The enhanced ability to evaluate the measurement data 20 and reduce the overall uncertainties; and (2) An enhanced technique to collect the LOB data. These two things are described in this description.
FIG. 3 is a drawing of how emitter locating is presently done today with three or more DF Sets. The DF Sets are connected through a communications link so the LOB data from each DF Set is used to triangulate the position of the transmitter. The result is a transmitter's location that sometimes contains large uncertainties.
FIG. 4 is a drawing of the technique of this invention for collecting data. In this case, at least one of the DF Sets is mobile. Only one is shown in FIG. 4 , the mobile unit can be a part of a larger network of more DF Sets though. The transmitter's position is calculated much more accurately and in real-time with a combination of data-taking technique and the specialized method to handle the data streams. The result is a transmitter's location that contains reduced uncertainties and errors and is more accurate.
The technique of this invention involves the use of a mobile DF Set in a EL System. There may be one or multiple DF Sets used. The first step is for the mobile DF Set to take an LOB measurement of transmitter 12 . This process involves taking the LOB data and the so-called “quality number” reading from the DF receiver. Modem DF receivers now produce a quality number with every LOB output. This quality number value is a metric by which the DF receiver manufacturer estimates the probability that a measurement is accurate. The computer 26 then takes this quality number along with the actual LOB measurement and stores them in memory for future processing.
The next step is for the mobile DF Set to move its physical position with respect to the transmitter's position. While moving, the DF Set is constantly taking in more LOB data and associated quality numbers. This process goes on for as long as required to find the transmitter. The more data that is collected, the higher will be the probability that the triangulated position of the transmitter is where it is expected to be.
This invention employs a specialized recursive method in the computer to process the LOB data that is continually being stored. The whole process begins after a “cross-over” point is first found. A cross-over point is the intersection between the last best LOB data entry, and the newly arrived LOB; typically a point where two LOB's cross (a position having a fairly high confidence level).
This cross-over point, when fixed on a map, is the original triangulated position (hereafter referred to as the “position point”) of the transmitter.
Next, a new LOB is measured and taken into account. The method calculates the shortest distance between the last best position point, and the newly arrived LOB. This will be a perpendicular vector from the point to the line-of-bearing. The method then calculates a new best guess position point along this vector, taking into account the new LOB's associated quality number as a weighting. Again, this calculation can be done in real time since the method is recursive, and therefore does not require the recomputing of every single LOB data entry taken up to that point.
In essence, the method uses a form of feedback control with an expected outcome. This recursive process is the basis of the method's uniqueness when applied to reducing measurement uncertainties in EL Systems. The measurement update steps of the method are responsible for incorporating every new measurement into the a priori estimate to obtain an improved a posteriori estimate.
LOB measurements that have a low quality number will be given less weight in the method when calculating the position points. LOB measurements that have a high quality number will be given much more weight in the same method. The method then outputs the “adjusted” output accordingly given the continuous stream of data points. This process will in effect prioritize the higher probability measurements designated by the quality number. Thus, the computer displays to the EL operator a much more accurate fix to the transmitter than can be achieved by simple averaging means of the entire data sets. The method of this invention is a form of statistical filtering.
This method has the ability to do real-time processing. Simple averaging of values requires more multiplications, thus the old method of averaging is slower and not able to be used in real-time if a large amount of data is used. The newer method of this provisional patent application uses fewer multiplications and thus can be performed by any standard processor and computer. To reiterate, the method's recursive nature thus makes practical implementations much more feasible than simple averaging, which is designed to operate on all of the data directly for each estimate. This is a unique and distinguishing advantage of the invention when used in EL Systems.
It is worthy of note that the spreading of position points across an integrated map display gives essentially the size of a “probability field” where the transmitter is most likely to be located. As more position points are calculated that deviate from each other, the probability field can be shown to grow on a map display. Such a display is the topic of another invention described in a provisional patent application entitled: “Technique and Method for Displaying Probabilistic Locations of Transmitters in Emitter Location Systems” that is the subject of pending patent application Ser. No. 10/785,356.
FIG. 5 is a flow chart depicting the prior art DF method for locating a transmitter. As shown, the EL system receives a stream of Line of Bearing and Quality information from at least three DF sets 42 A, 42 B and 42 C; three DF sets is generally the minimum necessary in order to achieve triangulation. Next, the EL system calculates the average Line of Bearing from a particular segment of each DF set 44 A, 44 B and 44 C. These averaged Lines of Bearing from each DF set to the transmitter are then plotted 46 to result in a conclusion by the EL system as to the transmitter's location 48 . As discussed above, the target problems to be resolved by the present invention is the delay in arriving at the average Line of Bearing for each DF set, the lack of control and understanding of the inherent error in each of the LOB averages, and also the need for three or more active and high-quality DF set LOB signals in order to arrive at any sort of reliable transmitter position. FIG. 6A shows the fundamentals of how the present approach operates.
FIG. 6A depicts the DF set at two subsequent locations. For the purpose of clarifying the geometry of the locating solution method, however, the DF set is shown as stationary (relative to the transmitter location graphical solution). As a result, FIG. 6A can be considered to be a DF Set-centric view, wherein the DF set appears to be stationary and any lines of bearing or transmitter locations are in relation (or relative to) the moving DF set. In fact, the transmitter might actually be stationary in the depicted FIG. 6 , with all relative movement being provided by the transmitter. First, PP( 0 ) (the cross-over point) is determined as discussed in the Specification previously. As the DF Set is then moved, the line of bearing to the cross-over point will continue to “point” towards PP( 0 ). When a new DF Set location is reached and a new line of bearing is “drawn” to the newly-detected transmission. The connecting vector, in this example, is then drawn perpendicular to the latest line of bearing, through the last line of bearing or estimate position (in this case it is PP( 0 )).
FIG. 6B graphically depicts the method of the present invention (as specifically described below in connection with the description associated with FIG. 7 ), from an “Earth-centric” or reference frame fixed in relation to the earth.
Next, the EL system obtains another Line of Bearing (LOB( 1 )) to the transmitter (PP( 1 )), and constructs a connecting vector 52 that is perpendicular to the current line of bearing (LOB( 1 )), and ends at the last line of bearing (in this case, PP( 0 ), the cross-over point). This method assumes that the higher the quality number associated with LOB( 1 ), the higher the probability that PP( 1 ) actually lies on the connecting vector 52 . This process is repeated, and more LOB's are obtained, until such time as the EL system determines a high probability of the location of the transmitter.
FIG 6 depicts the DF set at two subsequent locations. For the purpose of clarifying the geometry of the locating solution method, however, the DF set is shown as stationary (relative to the transmitter location graphical solution). As a result, FIG. 6 can be considered to be a DE Set-centric view, wherein the DF set appears to be stationary and any lines of bearing or transmitter locations are in relation (or relative to) the moving DF set. In fact, the transmitter might actually be stationary in the depicted FIG. 6 , with all relative movement being provided by the transmitter. First, PP( 0 ) (the cross-over point) is determined as discussed in the Specification previously. As the DF Set is then moved, the line of bearing to the cross-over point will continue to “point” towards PP( 0 ). When a new DE Set location is reached and a new line of bearing is “drawn” to the newly-detected transmission. The connecting vector, in this example, is then drawn perpendicular to the latest line of bearing, through the last line of bearing or estimate position (in this case it is PP( 0 )).
Three things should be noted: (1) in order to be most effective, the DF set 10 must be exhibit motion relative to the transmitter, so that the LOB's will change somewhat as more and more readings are taken; (2) there is no need for three or even two DF sets in order to determine a “fix” or actual position for the transmitter with this method; and (3) all position determinations are made “on the fly,” in real-time. Turning to FIG. 7 , we can see how the entire method of the present invention executes.
FIG. 7 is a flow chart depicting the real-time DF method 54 for locating a transmitter of the present invention.
First, the EL system receives at least one transmission from a transmitter 56 A. The system will next generate a first Line of Bearing that represents the received transmission from transmitter( 1 ) 58 A. Next, the DF set is relocated 60 A (preferably relative to transmitter( 1 )). Another transmission is received from transmitter( 1 ) 56 B, and a new Line of Bearing is generated 58 B representing the direction that transmitter( 1 ) was from DF set( 1 ) when the transmission was received. The LOB's are then analyzed to determine whether or not they cross one another 62 . If they do not, then the implication is that one or both have so much error in them that it would not be advisable to use their data. In this case, DF set( 1 ) is relocated again 60 B, and another transmission is received and LOB generated, until such time as when two sequential LOB's do cross one another. When two LOB's cross, a cross-over point in identified 64 at the spacial location of the crossing of the LOB's—this is the first “Best Guess” at the location of transmitter( 1 ). It should be noted that the operator can simply select a cross-over point manually, in order to expedite the process—while this will effect the initial accuracy of the position locating process, as more sample data is taken, even this error will be resolved.
Once the cross-over point has been determined 64 , DF set( 1 ) is relocated again 60 C, and another transmission is received from transmitter( 1 ) 56 C. Another LOB is generated 58 C representing the direction to transmitter( 1 ) from DF set( 1 ). At this stage, a “connecting vector” (see FIG. 6 ) is generated from the last “Best Guess” location to the latest LOB 66 . Next, a “New Best Guess” location is generated along the connecting vector, with its proximity to the last best guess being determined by the quality number of the latest transmission (and LOB), weighed against the weight of the last best guess (which is a factor of sample size and quality of the data that led to the last best guess's location).
The New Best Guess location will be identified for the user as transmitter( 1 )'s location 70 , updated in real-time (unlike the prior systems). The system 54 then continues to relocate the DF set 60 D and receive transmissions in order to continue to determine the location of transmitter( 1 ).
It should be understood that no matter how bad the transmission data and resultant LOB's are, it will not impact the system's ability to provide a transmitter location to the user, since the “best guess” approach described herein is resilient to erroneous and/or random data.
Those skilled in the art will appreciate that various adaptations and modifications of the just-described preferred embodiment can be configured without departing from the scope and spirit of the invention. Therefore, it is to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described herein.
DIAGRAM REFERENCE NUMERALS
10 DF Set
11 EL System
12 Transmitter (Emitter)
14 RF signals
16 DF antenna array
18 DF receiver
20 Line-Of-Bearing (LOB) measurement data and quality number
22 GPS device
23 Compass device
24 DF Set Position data
25 DF Set Orientation data
26 Computer
30 Communications link
32 Triangulated position data plotted on a map display
34 Triangulated position data that has reduced uncertainties, plotted on a map
36 Direction movement vector of mobile DF Set in an EL System
42 Conventional LOB receipt steps
44 Conventional LOB average calculation steps
46 Conventional LOB intersection plotting step
48 Conventional transmitter location determination step
50 and 54 Real-time DF determination method
56 – 70 steps incorporated into the method of the present invention | A Real-time Emitter Locating (EL) System and Method is disclosed. The system provides a technique for taking in data sets (lines of bearing) from DF receivers and characterizing those signals with their respective probabilities of error. Then using a unique method, the preferred system applies a recursive processing technique to this continuous stream of data, displaying transmitter positions with significantly less uncertainty. Furthermore, the preferred system is able to perform these functions in real-time. The system is further capable of being fully automated to reduce the processing time and reduce the necessity of human intervention. Still further, in an alternative embodiment of the present invention the system can be remotely controlled over a communications network whereby collected locating data from a single DF set, or alternatively from more than one DF sets can be combined to arrive at estimated positions for a transmitter. In this way, a far more efficient EL System can be achieved in which the emitter's position can be determined more quickly from a centralized command facility. This combination of data filtering and data collection techniques significantly reduces measurement uncertainties and enhances the accuracy of EL systems. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to a method of preserving sperm to be used for the artificial insemination of domestic animals, and especially for the artificial insemination of swine.
THE PRIOR ART
Sperms of domestic animals have heretofore been preserved at temperatures below the freezing point. For example, the freeze-preservation method has been widely employed for preserving the sperm of cattle. However, no attempt has been successful for preserving the sperm of swine because of the following reasons, namely, the insemination of swine requires sperm in amounts larger than those of other domestic animals, and there is so far available no suitable substance for protecting the sperm from the freezing temperatures.
Therefore, there has been proposed a method of preserving the sperm in a liquid state by adding a diluting solution to the sperm. This method is effective when the sperm is to be preserved for only short periods of time. When the sperm is to be preserved for 7 to 10 days, however, the above method is not capable of maintaining the spermatic activity which is necessary for accomplishing the artificial insemination. With the above-mentioned liquid preservation method, furthermore, an increased number of spermatozoa turn out to be defective in the acroworm (head cap).
Therefore, it has been attempted to preserve the sperm at a temperature of as low as several degrees centigrade to extend the time over which the sperm can be effectively preserved. According to this method, however, the sperm collected from the animal must be cooled from a temperature close to the body temperature (about 37° C.) of the animal to the cooling temperature at such a low rate as 1° to 2° C. per hour. Therefore, the lower the preservation temperature, the longer the cooling time required, while necessitating a specially designed cooling apparatus.
OBJECT OF THE INVENTION
The object of the present invention is to provide a method of preserving the sperm which is free from the defects inherent in the above-mentioned conventional methods, which helps maintain the spermatic activity which is necessary for the artificial insemination even when the sperm is preserved for extended periods of time, which prevents the spermatozoa from becoming defective during the preservation, and which does not require any complicated cooling operation.
SUMMARY OF THE INVENTION
The present invention involves a method of preserving the sperm of a domestic animal by contacting through a dialytic membrane said sperm with a Ringer's solution containing albumin or activated carbon.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings illustrate a preservation vessel used for putting the method of the present invention into practice,
FIG. 1 being a cross-sectional view, and
FIG. 2 being a plan view.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The method of the present invention is put into practice by using a vessel shown schematically in FIG. 1. The vessel 1 contains a dialytic tube 2 which has an injection port 3. An injection port 4 is also formed in the space between the dialytic tube 2 and the vessel 1. The injection ports 3 and 4 are secured by a ring 7, and are hermetically closed by plugs 5 and 6, respectively.
The sperm which is collected or the sperm which is diluted with a diluting solution is injected into the dialytic tube 2, and the injection port is hermetically sealed by the plug 5. A Ringer's solution 9 containing albumin or activated carbon is injected into the space between the dialytic tube 2 and the vessel 1. The vessel 1 containing the sperm 8 and the Ringer's solution is preserved in a refrigerator maintained at a constant temperature (which is desirably set at about 15° C.).
The method of the present invention is effective for preserving the sperm presumably because of the reasons mentioned below.
At a preservation temperature of about 15° C., the activity of the sperm is halted but the metabolism continues. Consequently, nutrients such as carbohydrates are consumed, and substances such as organic wastes which are harmful to the survival of the spermatozoa are formed.
Proteins such as albumins or the activated carbon works to adsorb harmful substances such as organic wastes and, hence, presumably remove harmful substances, formed in the sperm, through the dialytic membrane. The albumin can be selected from glair albumin, serum albumin, and the like. The activated carbon should be washed with hot water and should be relieved of harmful substances such as chlorine and the like.
Although it may vary depending upon the shape of the preservation vessel, the albumin or the activated carbon exhibits sufficient effects when it is used in the amount of a dialytic solution (about 0.5 to about 1.0% for the albumin, and about 0.25 to about 0.5 NT% for the activated carbon). The Ringer's solution is saline water containing about 0.9% of sodium chloride, and works to dissolve or disperse the albumin or the activated carbon as well as to adjust the ion concentrations and pH values inside and outside the dialytic membrane. In the specification of the present application, however, saline waters to which is added a reflux for artificial kidney use, such as a KRB solution (KreboRinger bicarbonate solution), or a KRP solution (Krebo-Ringer phosphate solution) in addition to the sodium chloride, will also be referred to as the Ringer's solution. An anti-biotic substance such as streptomycin or sulpenicillin may be added to the sperm which is to be preserved so that the spermatozoa are prevented from being killed by the propagation of bacteria.
The dialytic membrane is a film having fine pores of a size which permits the organic wastes formed in the sperm to pass through but does not permit the spermatozoa or the albumin or the activated carbon to pass through. The dialytic membrane can be prepared by utilizing a commercially available dialytic membrane for artificial kidneys made of a cellulose film or a plastic film, or by utilizing a porous film. In the embodiment shown in FIG. 1, the sperm 8 is contained on the inner side of the dialytic tube 2, and the Ringer's solution 9 is contained on the outer side of the dialytic tube 2. As illustrated in FIG. 2, furthermore, the dialytic tube 2 may be hermetically sealed and immersed in the dialytic solution without being fitted with the plug. In other words, the vessel may be of any shape provided the sperm and the Ringer's solution are permitted to come into contact with each other via the dialytic membrane.
In preserving the sperm, good results can be obtained when the dialytic tube 2 is maintained horizontally, rather than vertically supported. This is presumably due to the fact that organic wastes can be easily removed when the spermatozoa precipitated by the force of gravity are dispersed over wide areas on the surface of the dialytic membrane.
EXAMPLE 1
The sperm of a swine contained in the vessel 1 shown in FIG. 2 was preserved for 7 days in a refrigerator in which the temperature was maintained at 15° C., to measure the activity of the spermatozoa and the ratio of spermatozoa having a normal head cap. The results were as shown in Table 2. The sperm preserved was also introduced into the dialytic tube 2 in its own form and was dialyzed with Ringer's solutions of compositions as shown in Table 1.
TABLE 1______________________________________No. Sperm Composition of Ringer's solution______________________________________1 5ml of sperm 20ml of KRB solution containing 0% ofin its own adsorbing agent, and 20% of glucoseform solution at a concentration of 5.05%2 same as 20ml of KRB solution containing 0.125%above of activated carbon and 25% of glucose solution at a concentration of 5.05%3 same as 20ml of KRB solution containing 0.25%above of activated carbon and 25% of glucose solution at a concentration of 5.05%4 same as 20ml of KRB solution containing 0.5%above of activated carbon and 25% of glucose solution at a concentration of 5.05%5 same as 20ml of KRB solution containing 1.0% ofabove activated carbon and 25% of glucose solution at a concentration of 5.05%6 same as 20ml of KRB solution containing 2.0% ofabove activated carbon and 25% of glucose solution at a concentration of 5.05%______________________________________
TABLE 2______________________________________ Ratio of spermatozoa having normal headSpermatic activity (%) cap After AfterSpeci- Before pre- Before pre-men pre- servation pre- servationNo. servation for 7 days servation for 7 days______________________________________1 95 +++ 58.4 ± 11.9 89 +++ 47.0 ± 13.1 KG31 + activated carbon (0%)2 95 +++ 63.7 ± 10.8 89 +++ 55.6 ± 12.4 KG31 + activated carbon (0.125%)3 95 +++ 69.6 ± 6.9 89 +++ 62.5 ± 10.3 KG31 + activated carbon (0.25%)4 95 +++ 67.5 ± 8.7 89 +++ 57.6 ± 10.2 KG31 + activated carbon (0.5%)5 95 +++ 61.8 ± 15.6 89 +++ 56.0 ± 12.4 KG31 + activated carbon (1.0%)6 95 +++ 50.3 ± 18.5 89 +++ 49.8 ± 12.9 KG31 + activated carbon (2.0%)______________________________________
The collected sperm was introduced in its own form into the dialytic tube 2, inserted into the vessel 1 filled with the Ringer's solution, and after the vessel was sealed, the sperm was cooled to about 15° C. over a period of 3 to 4 hours to preserve it in a refrigerator. The thus preserved sperm was then centrifugally precipitated, and the spermatozoa were allowed to float in the KRP solution to which a glucose and a catalase had been added, to culture them at 37° C. for 1 hour. The spermatic activity was then examined. The spermatic activity was indicated by percentage (+++%) relying upon the number of actively moving spermatozoa in the sight of a microscope with the total number of spermatozoa in the sight being 100. The ratio of spermatozoa having a normal head cap was examined relying upon the samples of Dott and Foster dyed with Eosine and Nigrosine as viewed through a microscope having a magnification of 600 times. Those which were not apical ridge-deformed were regarded to be normal, and other spermatozoa were regarded as defective. The ratio of normal spermatozoa was indicated by a percentage. The Ringer's solution, to which are added, as anti-biotic substances, the streptomycin in an amount of 1 mg/ml and sulpenicillin in an amount of 1 mg/ml, added to the sperm and to the dialytic solution, is usually called a KRB solution, and has the following composition:
______________________________________Sodium chloride 0.9% solution 100 parts by volumepotassium chloride 1.15% solution 4 parts by volumecalcium chloride 1.22% solution 3 parts by volumepotassiumdihydrogenphosphate 2.11% solution 1 part by volumeheptahydrate of 3.22% solution 1 part by volumemagnesium sulfatesodium bicarbonate 1.30% solution 21 parts by volumesaturated withcarbon dioxide gas______________________________________
According to the method of the present invention as mentioned above, the spermatic activity necessary for the artificial insemination can be maintained even when the sperm is preserved for as long as 7 to 10 days, permitting the spermotozoa to become less susceptible to damage during preservation. Furthermore, since the sperm can be desirably preserved at a temperature of 15° C., which is close to room temperature, the collected sperm can be cooled to the preservation temperature simply by leaving it to cool at room temperature for 3 to 4 hours. Consequently, the method of the present invention does not require a cumbersome cooling operation which is needed for the method of low-temperature preservation. | In a method of preserving sperm of domestic animals, especially for the purposes of artificial insemination, a quantity of the sperm, diluted if necessary with a diluting solution, is maintained in communication, through a dialytic membrane, with a quantity of Ringer's solution containing albumin or activated carbon, the whole being maintained at a constant temperature preferably of about 15° C. An antibiotic may be added to the sperm to prevent bacterial growth. | 0 |
This application is a continuation of U.S. application Ser. No. 14/012,720 filed Aug. 28, 2013, which is a continuation of U.S. application Ser. No. 12/888,188 filed Sep. 22, 2010, now U.S. Pat. No. 8,524,457 issued Sep. 3, 2013, which claims priority to U.S. Provisional No. 61/244,770 filed Sep. 22, 2009, each of which are incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
The invention generally relates to the field of immunochemistry including antibody therapy, diagnostics, and basic research and specifically relates to the area of selecting affinity molecules such as natural antibodies, including artificial antibodies, antibody mimics, and aptamers. The invention relates particularly to a method of selecting affinity molecules using a homogeneous noncompetitive assay in a high throughput process.
BACKGROUND OF THE INVENTION
Antibodies and specific alternatives are a standard tool for research product, diagnostic, and therapeutic applications. Discovery and characterization of affinity reagents for these applications can be challenging and arduous, involving antigen preparation, in vitro and/or in vivo development of binders, as well as screening and isolation of those binders. For example, mouse monoclonal antibodies are generated by immunization of mice with a purified antigen, to allow in vivo development of IgG antibodies by the B cells, and selection of an appropriate antibody by screening the expression of hybridomas (Köhler & Milstein Nature (1975) 256(5517):495-7). More recently, antibody fragments (e.g., single chain variable fragments (scFv), and V H H domains) and artificial affinity binders (e.g., Affibodies, Monobodies, and DARPins) have been created and are developed by screening large gene libraries of potential binders with various panning technologies. These technologies have allowed the development of numerous protein scaffolds with unique affinity interaction domains that bind target epitopes.
A plethora of affinity molecule panning/screening technologies have been developed over the past decade and all share the requisite association of expressed protein with its nucleic acid coding sequence, which serves to identify the affinity binder. These technologies can be generally divided into two groups: in vivo and in vitro display. In vivo technologies are based on the introduction by viral infection or cellular transfection of a single gene into a cell, expression of the affinity binder protein from the gene, delivery of the binder to the surface of the cell or phage, selection of the affinity molecule to an immobilized target molecule, and identification of the gene associated with the affinity binder (Hoogenboom, H. R. (2005) Nature Biotech 23(9), 1105-16). Examples of in vivo type display technologies are bacterial, yeast, mammalian, insect, and phage display.
In vitro technologies use the basic protein expression apparatus of a cell, either as a cell extract or a purified system (Shimizu, et al. Nature Biotechnology (2001) 19, 751-755), but do not require a viable cell to express the affinity binder. Therefore, the required association of coding sequence with affinity binder is through a physical bond. For ribosome display, this is done by “freezing” the ribosome at the end (stop codon) of an mRNA transcript after it has completed translating the transcript into a protein, which is also bound to the ribosome (Hanes, J. et al. (1998) Proc Natl Acad Sci USA 95(24), 14130-5). Affinity molecules to the target molecule are selected similarly to in vivo display technologies (i.e., with an immobilized target molecule) and the mRNA transcript reverse transcribed into DNA for amplification, identification, and cloning. RNA display covalently links the 3′ end of an mRNA transcript to the translated affinity molecule protein using a linker, which is added to the 3′ ends of the mRNA and incorporated into the affinity binder protein at its C-terminal end (Roberts, R. W., and Szostak, J. W. (1997) PNAS 94(23), 12297-302). DNA display physically associates the affinity molecule to the DNA coding sequence, either using a DNA replication initiator protein (RepA) fused to the affinity binder (ref) or a Hae III DNA methyltransferase that specifically recognizes methylated sequences (Bertschinger & Neri Protein (2004) Eng. Des. Sel. 17(9), 699-707). While the former can be performed in solution, the latter requires individual reactions for each protein expression event using in vitro compartmentalization.
In vitro compartmentalization (IVC) was developed in 1998 by Andrew Griffiths and Dan Tawfik (Nature Biotech. 16, 652) as an alternative to standard reaction vessels. Using cellular compartmentalization as a model, this technology facilitates the creation of minuscule aqueous solutions using water-in-oil emulsions, that is, small droplets of hydrophilic fluid exist as individual compartments in a sea of hydrophobic fluid. Droplets can be less than a micron in size (less than a femtoliter in volume) and an emulsion can have greater than 10 10 droplets per ml. Griffiths and Tawfik demonstrated that a gene library distributed in a cell-free extract and compartmentalized into droplets can express their individual proteins in each droplet. In one case, the protein is an enzyme that reacts with a substrate and the technique can be used to evolve the enzyme with desired attributes. In another case, the gene is covalently bound to a bead that also contains an affinity molecule that captures the gene product (e.g., using a protein tag), thereby associating the gene with its expression product for affinity molecule selection. In addition, there is the technique noted above that uses Hae III DNA methyltransferase.
Homogeneous noncompetitive immunoassays by definition do not require physical separation of an affinity molecule bound to its target before detection. A common example of this technique is aggregation or agglutination immunoassays. Another example is Förster (or fluorescence) resonance energy transfer (FRET), which is based on the transfer of Förster energy (nonradiative transfer) from an excited fluorophore to another fluorophore that is in proximity (Valanne et al. (2005) Anal. Chim. Acta 539, 251-6). A similar method uses a bioluminescent protein, such as luciferase, to excite a proximal fluorophore (BRET), typically a fluorescent protein (Xu et al. (1999) Proc. Natl. Acad. Sci. USA 96(1), 151-6). Another homogeneous assay alternative is a luminescent oxygen-channeling chemistry (Ullman et al. (1994) Proc. Natl. Acad. Sci. USA 91(12), 5426-30), wherein a light induced singlet oxygen generating system transfers the singlet oxygen to a chemiluminescent system in proximity. The NanoDLSay system is a single-step homogeneous assay that uses conjugated gold particles to form aggregates in the presence of an antigen (Liu et al (2008) J. Am. Chem. Soc. 130 (9), 2780-2). Proximity ligation assay (PLA) uses two DNA single strands, one attached to each affinity molecule partner, that are complementary to a third oligonucleotide (Gullberg (2004) Proc Natl Acad Sci USA 101(22), 8420-8424). When the affinity molecules are proximal to each other, the strands hybridize to the linker oligonucleotide in an orientation where ends (3′ and 5′) are next to each other and can be ligated together. The resulting DNA is amplified and quantified using Q-PCR.
Protein fragment compartmentalization (PFC) is similar to PLA in that 2 complementary molecules are fused to potentially proximal binders that interact preferentially when in proximity. In this case, the molecules are protein fragments capable of assembling into a complete and functional protein, typically an enzyme or fluorescent protein. Protein-protein interaction sensors using protein fragments were first developed by Nils Johnsson and Alexander Varshaysky using a split ubiquitin and this idea was further developed by Stephen Michnik in 1997 (Pelletier et al. (1998) J. Biomol. Tech. acc. No. 50012) as an in vivo protein-protein interaction analysis tool. The technique was used to develop an in vivo antibody (scFv) screening method by fusing one protein fragment on the antigen and the other protein fragment on a library of scFv (Mössner et al. J. Mol. Biol. (2001) 308(2), 115-122; Koch et al. J. Mol. Biol. (2006) 357, 427-441; Secco et al. (2009) Prot. Evol. Des. Sel. 22(5), 149-158). Recently, Panbio Diagnostics has developed a homogeneous assay for the detection of antigen or antibodies using protein fragment complementation, which they call Forced Enzyme Complementation (FEC).
Most examples of affinity binder screening by PFC are in vivo, that is, the binding reactions are compartmentalized using cells. As mentioned above, an alternative to using live cells is encapsulated cell-free extracts using IVC, preferably manipulated using microfluidics. While there are numerous examples of in vitro protein expression using IVC, only recently has this been done using microfluidic devices. Dittrich, et al. (Chembiochem. (2005) 6(5):811-4), has recently demonstrated in vitro expression of a green fluorescent protein (red-shifted mutant) in 5 micron (˜65 fL) microdroplets that were detected using confocal fluoroscopy. Few other researchers have developed this technology, preferring to use compartmentalized cell based assays (Brouzes et al. PNAS (2009) early edition).
SUMMARY
In some embodiments, the present invention provides a method for screening specific affinity molecules to target molecules using a homogeneous noncompetitive assay. In some embodiments, the method comprises use of reagents to perform a homogeneous non-competitive assay, in which candidate affinity molecules are used to conduct the homogeneous non-competitive assay in order to identify candidate affinity molecules with affinity for the target as indicated by a positive result in the homogeneous non-competitive assay. In some embodiments, the affinity molecules are native antibodies, antibody fragments, artificial antibody scaffolds, peptides, or nucleic acids. In some embodiments, the native antibodies are IgG, IgM, IgA, or IgE molecules; the antibody fragments include (Fab) 2 , Fab, and scFv; and the artificial antibody scaffolds include Nanobodies, Affibodies, Anticalins, DARPins, Monobodies, Avimers, and Microbodies. In some embodiments, peptides are greater than three amino acids, consist of either natural or non-natural amino acids, and include peptide aptamers; the peptides are covalently attached to a carrier molecule. In some embodiments, the nucleic acid includes nucleic acid aptamers and peptide nucleic acids (PNA). In some embodiments, the affinity binders are expressed from genes or chemically synthesized. In some embodiments, the affinity molecules are comprised of a tyrosine/serine binary-code interface or a tyrosine/serine/X amino acid tertiary-code interface. In some embodiments, two or more affinity molecules are required to bind to at least 2 different epitopes of a target molecule. In some embodiments, the binding of the first known affinity molecule and a second unknown affinity molecule is an individual reaction performed in an individual vessel. In some embodiments, the individual vessel is a single reaction tube or a well of microtiter plate. In some embodiments, the individual vessels are water microdroplets, wherein water microdroplets can be created by water-in-oil technology. In some embodiments, the water microdroplets are created using micro- or nanofluidic devices, wherein a micro- or nanofluidic device is used to manipulate microdroplets to mix reagents, perform reactions, heat, cool, detect and analyze assay output, and sort into various collection systems. In some embodiments, the reaction vessels are in vivo cells including bacteria, archaebacteria, fungal, insect, and mammalian cells.
In some embodiments, one affinity molecule is associated with a protein fragment via a flexible linker that complements another protein fragment associated with the second affinity molecule via a flexible linker. In some embodiments, complementation of the protein fragments associated with affinity molecules generates a measurable signal. In some embodiments, the measurable signal includes color, fluorescence, and bioluminescence. In some embodiments, the affinity molecules are in proximity when bound to the target to allow complementation of associated protein fragments. In some embodiments, one affinity molecule is associated with a donor fluorophore via a linker that can transfer Forster energy to an acceptor fluorophore that is linked via a linker to the second affinity molecule. In some embodiments, one affinity molecule is associated with a bioluminescent protein via a linker that can transfer Förster energy to an acceptor fluorophore that is linked via a linker to the second affinity molecule. In some embodiments, one affinity molecule is associated with a light induced singlet oxygen generating system via a linker and the second affinity molecule is a singlet oxygen dependent chemiluminescent system (luminescent oxygen channeling). In some embodiments, the affinity molecules are associated with gold particles conjugated with anti-epitope antibodies that aggregate when the reference affinity molecule and the unknown affinity molecule (each with a different epitope tag) bind.
In some embodiments, the first affinity molecule is the reference affinity molecule and is known to bind the target with relatively high affinity while the binding affinity of the second affinity molecule is not known, but is determined by the homogeneous noncompetitive assay. In some embodiments, the first affinity molecule has affinity for an epitope tag that is added to the target, wherein the epitope tag is polypeptide expressed along with the protein affinity molecule, including, but not limited to, His-tag, FLAG-tag, V5-tag, HA-tag, and c-myc-tag. In some embodiments, the epitope tag is covalently bonded to the target. In some embodiments, the second affinity molecule is derived from a library of potential affinity molecules.
In some embodiments, the target molecule may be a protein, glycoprotein, phosphoprotein, other post-modification protein, protein complex, nucleic acid, protein:nucleic acid complex, carbohydrate, lipid complex, organic and inorganic molecule, including natural and synthetic versions of any such molecules. The target or target molecules may comprise a single protein or other biomolecule or multiple molecules (e.g., in a multi-molecular complex). For example, in some embodiments, affinity molecules are used to simultaneously bind two or more molecules that are in proximity to one other, to, for example, detect such proximity.
Embodiments of the present invention further provide methods of using the complexes in therapeutic, diagnostic, and basic or applied research settings (e.g., drug screening applications).
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing summary and detailed description is better understood when read in conjunction with the accompanying drawings which are included by way of example and not by way of limitation.
FIG. 1 shows a cartoon representing a simple design of some embodiments, showing an affinity complex comprising a target and two affinity molecules with attached complementary detection molecules. The target is represented by the spotted square with corner knockouts, which represent epitopes of the target. The reference affinity molecule (oval with downward diagonal) binds to one epitope and is associated to a detection molecule (oval with checkerboard). The unknown affinity molecule (oval with downward diagonal) binds to another epitope of the target and is associated to a complementary detection molecule (oval with squares). The 2 complementary detection molecules function only when in proximity.
FIG. 2 shows an example of a microfluidic device. An immiscible fluid is pumped through the pathway of the device and an aqueous fluid containing an affinity molecule gene library in a cell-free translation solution is injected forming microdroplets. Upon protein expression, the affinity molecules bind to a target, the detection molecules are allowed to interact, and detected in a sorting chamber. Positive samples are gated to a collection bin while negative microdroplets are gated to the waste.
DEFINITIONS
As used herein, the term “about” means encompassing plus or minus 10%. For example, about 200 nucleotides refers to a range encompassing between 180 and 220 nucleotides.
As used herein, the term “gene” refers to a nucleic acid (e.g., DNA) sequence that comprises coding sequences necessary for the production of a polypeptide, precursor, or RNA (e.g., rRNA, tRNA). The polypeptide can be encoded by a full length coding sequence or by any portion of the coding sequence so long as the desired activity or functional properties (e.g., enzymatic activity, ligand binding, signal transduction, immunogenicity, etc.) of the full-length or fragment is retained. As used herein, the term “heterologous gene” refers to a gene that is not in its natural environment. For example, a heterologous gene includes a gene from one species introduced into another species. A heterologous gene also includes a gene native to an organism that has been altered in some way (e.g., mutated, added in multiple copies, linked to non-native regulatory sequences, etc). Heterologous genes are distinguished from endogenous genes in that the heterologous gene sequences are typically joined to nucleic acid sequences that are not found naturally associated with the gene sequences in the chromosome or are associated with portions of the chromosome not found in nature (e.g., genes expressed in loci where the gene is not normally expressed).
As used herein, the term “nucleic acid molecule” refers to any nucleic acid containing molecule, including but not limited to, DNA or RNA. The term encompasses sequences that include any of the known base analogs of DNA and RNA including, but not limited to, 4 acetylcytosine, 8-hydroxy-N6-methyladenosine, aziridinylcytosine, pseudoisocytosine, 5 (carboxyhydroxyl-methyl) uracil, 5-fluorouracil, 5 bromouracil, 5-carboxymethylaminomethyl 2 thiouracil, 5 carboxymethyl-aminomethyluracil, dihydrouracil, inosine, N6 isopentenyladenine, 1 methyladenine, 1-methylpseudo-uracil, 1 methylguanine, 1 methylinosine, 2,2-dimethyl-guanine, 2 methyladenine, 2 methylguanine, 3-methyl-cytosine, 5 methylcytosine, N6 methyladenine, 7 methylguanine, 5 methylaminomethyluracil, 5-methoxy-amino-methyl 2 thiouracil, beta D mannosylqueosine, 5′ methoxycarbonylmethyluracil, 5 methoxyuracil, 2 methylthio N6 isopentenyladenine, uracil 5 oxyacetic acid methylester, uracil 5 oxyacetic acid, oxybutoxosine, pseudouracil, queosine, 2 thiocytosine, 5-methyl-2 thiouracil, 2-thiouracil, 4 thiouracil, 5-methyluracil, N-uracil 5 oxyacetic acid methylester, uracil 5 oxyacetic acid, pseudouracil, queosine, 2-thiocytosine, and 2,6 diaminopurine.
As used herein, the term “oligonucleotide” refers to a nucleic acid that includes at least two nucleic acid monomer units (e.g., nucleotides), typically more than three monomer units, and more typically greater than ten monomer units. The exact size of an oligonucleotide generally depends on various factors, including the ultimate function or use of the oligonucleotide. To further illustrate, oligonucleotides are typically less than 200 residues long (e.g., between 15 and 100), however, as used herein, the term is also intended to encompass longer polynucleotide chains. Oligonucleotides are often referred to by their length. For example a 24 residue oligonucleotide is referred to as a “24-mer”. Typically, the nucleoside monomers are linked by phosphodiester bonds or analogs thereof, including phosphorothioate, phosphorodithioate, phosphoroselenoate, phosphorodiselenoate, phosphoroanilothioate, phosphoranilidate, phosphoramidate, and the like, including associated counterions, e.g., H + , NH 4 + , Na + , and the like, if such counterions are present. Further, oligonucleotides are typically single-stranded. Oligonucleotides are optionally prepared by any suitable method, including, but not limited to, isolation of an existing or natural sequence, DNA replication or amplification, reverse transcription, cloning and restriction digestion of appropriate sequences, or direct chemical synthesis by a method such as the phosphotriester method of Narang et al. (1979) Meth Enzymol. 68:90-99; the phosphodiester method of Brown et al. (1979) Meth Enzymol. 68:109-151; the diethylphosphoramidite method of Beaucage et al. (1981) Tetrahedron Lett. 22:1859-1862; the triester method of Matteucci et al. (1981) J Am Chem Soc. 103:3185-3191; automated synthesis methods; or the solid support method of U.S. Pat. No. 4,458,066, entitled “PROCESS FOR PREPARING POLYNUCLEOTIDES,” issued Jul. 3, 1984 to Caruthers et al., or other methods known to those skilled in the art. All of these references are incorporated by reference.
The term “sample” is used in its broadest sense. In one sense it can refer to an animal cell or tissue. In another sense, it is meant to include a specimen or culture obtained from any source, as well as biological and environmental samples. Biological samples may be obtained from plants or animals (including humans) and encompass fluids, solids, tissues, and gases. Environmental samples include environmental material such as surface matter, soil, water, and industrial samples. These examples are not to be construed as limiting the sample types applicable to the present invention.
A “sequence” of a biopolymer refers to the order and identity of monomer units (e.g., nucleotides, etc.) in the biopolymer. The sequence (e.g., base sequence) of a nucleic acid is typically read in the 5′ to 3′ direction.
As used herein, the term “affinity complex” refers to an interacting multicomponent collection of molecules that specifically interacts through interactions (e.g. hydrogen bonding, Van der Waals forces, electrostatic forces, hydrophobic forces, etc.) with a target molecule.
As used herein, the term “affinity molecule” refers to any molecule that specifically interacts through interactions (e.g. hydrogen bonding, Van der Waals forces, electrostatic forces, hydrophobic forces, etc.) with a target molecule.
As used herein, the term “artificial antibody” or “antibody mimic” refers to any non-immunoglobulin molecule or molecular complex that is created to specifically interact with a target molecule.
As used herein, the term “epitope” refers to any surface region of a target molecule to which an affinity molecule binds.
As used herein, the term “discontinuous epitopes” refers to two or more surface regions of a target molecule or molecules that are separated by a defined distance.
The term “paratope” refers to the surface region of an affinity molecule that interacts with the epitope of the target molecule.
As used herein, the term “affinity” refers to the non-random interaction of two molecules. The term “affinity” refers to the strength of interactions and can be expressed quantitatively as a dissociation constant (K D ). One or both of the two molecules may be a peptide (e.g. antibody). Binding affinity (i.e., K D ) can be determined using standard techniques. For example, the affinity can be a measure of the strength of the binding of an individual epitope with an antibody molecule.
As used herein, the term “avidity” refers to the cooperative and synergistic bonding of two or more molecules. “Avidity” refers to the overall stability of the complex between two or more populations of molecules, that is, the functional combining strength of an interaction.
As used herein, the term “protein fragment complementation” refers to a protein that can be fragmented into two or more parts so that when the fragments are in proximity they reform the original functional protein.
As used herein, the term “in vitro compartmentalization” refers to a method of creating cell-like compartments using emulsion (water-in-oil) technology.
As used herein, the term “Förster resonance energy transfer” or “FRET” refers to a process in which energy is transferred between an excited fluorophore (donor) and an acceptor fluorophore.
As used herein, the term “Bioluminescence resonance energy transfer” or “BRET” refers to a process in which energy is transferred between a bioluminescent protein and an acceptor fluorophore.
DETAILED DESCRIPTION OF EMBODIMENTS
In some embodiments, the present invention provides a method for screening specific affinity molecules to target molecules using a homogeneous noncompetitive assay in a high throughput process. In some embodiments, the present invention provides compositions, systems, and methods related to the screening of specific affinity molecules to target molecules using a homogeneous noncompetitive assay in a high throughput process. In some embodiments, the method comprises use of reagents to perform a homogeneous non-competitive assay, in which candidate affinity molecules are used to conduct the homogeneous non-competitive assay in order to identify candidate affinity molecules with affinity for the target as indicated by a positive result in the homogeneous non-competitive assay.
In some embodiments, a target molecule contains two or more epitopes to which the affinity binders can interact. In some embodiments, the epitopes are discontinuous. In some embodiments, the affinity molecules recognize the same epitopes. In some embodiments, the affinity molecules recognize different epitopes. In some embodiments, the affinity molecules recognize multiplexed targets.
Affinity Molecules
In some embodiments, the affinity molecule comprises or consists of a scaffold that has a region known as a paratope or a target epitope interaction domain and a detection molecule connected via a linker. In some embodiments, the paratope and detection molecule are situated to allow interaction with a target epitope and a freedom of the detection molecule. In some embodiments, each affinity molecule can comprise or consist of the same scaffold. In some embodiments, each affinity molecule can comprise or consist of different scaffolds.
In some embodiments, affinity molecules can be any antibody, antibody fragment, scaffold or molecular construct that has a paratope domain or region and a detection molecule domain or region. For example, IgG antibodies known to interact with a single target can used with a molecule that interacts with each Fc domain of the IgG (such as Protein A or G) and contains the detection molecule. In some embodiments, Fab fragments of an IgG antibody are employed as the affinity molecule and can be linked to the detection molecule through the constant domains (CL and CH1) of the molecule. In some embodiments, single chain fragments of the variable domains (scFv) are employed due to their increased stability. In some embodiments, the smaller size of the VHH domain of camelids (Nanobodies) is a preferred affinity molecule.
In some embodiments, the affinity molecule is a monobody (fibronectin type III domain) derived from a human cell surface protein. This scaffold is structurally similar to antibody variable domains, but does not contain disulfide bonds that can hinder expression in prokaryotic systems. In some embodiments, monobodies have a molecular weight of ˜10,000 Daltons, they are very soluble, and thermally and proteolytically stable. In some embodiments, the monobody scaffold contains three loops (BC, DE, and FG loops) that can be collectively employed as a paratope, similar to the CDR regions of an immunoglobulin. The polar opposite end of the paratope region contains three additional loops (AB, CD, and EF loops). In some embodiments, the N-terminal, C-terminal, or AB, CD, and EF loops can be employed as a linker to the detection molecule. In some embodiments, other linkers can be used, such as an abbreviated rPEG.
In some embodiments, the affinity molecule is a DARPin (designed ankyrin repeat protein) that is derived from a large class of repeat proteins found in various cellular sections in a variety of species. Each repeat consists of 33 amino acid residues that form a beta-turn followed by two anti-parallel helices and a randomized loop that is joined to the beta-turn of the next repeat and functions to “stack” the repeats generating a very stable hydrophobic core. In some embodiments, the loop and beta-turn sequences are involved in the paratope of the molecule. In some embodiments, residues of the helices can contribute to the paratope. In some embodiments, the combination of the loop and beta-turn sequences and the residues of the helices generate a broad paratope interface. In some embodiments, three or more of these repeats are created to generate a molecule with very high affinity. In some embodiments, the ends of the repeats are “capped” to preserve the hydrophobic core, increase its solubility and stability, and can be used for labeling or immobilization. In some embodiments, N-terminal and C-terminal caps are employed as linkers to the detection molecule.
In some embodiments, the affinity molecule is an Affibody (the Z domain of Staphylococcal protein A) that comprises or consists of 58 amino acids arranged as a bundle of 3 anti-parallel alpha helices. In some embodiments, the small size of the affibody molecule provides easier expression and solubility in prokaryotic systems. In some embodiments, the affibody polypeptide is chemically synthesized then folded, which allows the introduction of non-canonical amino acids in the interaction domain or the addition of labels or reactive groups. In some embodiments, the interaction domain comprises or consists of 13 amino acid residues that are randomized to generate a library from which an affinity molecule is panned. In some embodiments, binding affinities for affibodies and their substrates are in the nanomolar range.
In some embodiments, the affinity molecule is a Microbody (Nascacell Technologies). In some embodiments, a microbody is based on natural cysteine-knot microproteins and cyclical knottins. In some embodiments, Microbodies are small (28 to 45 amino acids), yet very stable due to three disulfide bonds within the structure, which allows the display of a single peptide loop up to 20 amino acids. In some embodiments, microbodies are very soluble and are expressed from bacteria or synthesized by chemical means then properly folded. In some embodiments, the stability and solubility of these proteins provides alternative therapeutic delivery modes to the standard injection of most biologicals. In some embodiments, a very similar molecule called a Versabody (Amunix), acts as a primary affinity molecule. In some embodiments, a Versabody is a very small high disulfide density scaffold based on natural biopharmaceuticals, such as scorpion toxin. Versabodies are extremely stable, soluble, and non-immunogenic.
In some embodiments, the affinity molecule is an Anticalin, an Avimer or the domain A of an Avimer, a thioredoxin, an ubiquitin, a gamma-crystallin, CTLA-4 (Evibody), or other recombinant artificial antibodies. In some embodiments, a primary affinity molecule is any molecule capable of binding a target with a suitable affinity.
In some embodiments, the affinity molecule is a nucleic acid or peptide aptamer, wherein the nucleic acid or peptide contains a target affinity domain and a detection molecule affinity domain.
Paratopes of Affinity Molecules
In some embodiments, the binding interaction of a paratope to its epitope is based upon a combination of molecular contacts that together account for the affinity strength (e.g. Van der Waals interactions, hydrogen bonding, and hydrophobic interactions), specific amino acid side groups of the paratope polypeptide form bonds with amino acid side groups of the epitope polypeptide. In some embodiments, a portion of the amino acids in the paratope function as structural support. In some embodiments, antibody mimics have a single polypeptide paratope, such as Affibodies and Versabodies. In these embodiments, the sum of those interactions determines the affinity. In some embodiments, affinity molecules comprise multiple polypeptide loops or CDRs (complementarity determining regions), such as fibronectin Type III domains, ankyrin repeats, and IgG molecules. These embodiments demonstrate additional number and spacing of those interactions. In some embodiments, the structure of the paratope should be adaptable to fit the epitope. In some embodiments, the paratope has enough flexibility to form bonds with the epitope without introducing intramolecular strain. In some embodiments, a large number of affinity molecules are be screened (e.g., in a binding assay) to achieve a suitable structure.
In some embodiments, only moderate affinity interactions are required. In some embodiments, only moderate affinity interactions are preferred. In embodiments, increased effectiveness of screening libraries is achieved when moderate affinity is sought. In some embodiments, binary- or tertiary-code library systems reduce the size of the libraries, increase their effectiveness, and further simplify the process. In some embodiments, the basis of the binary-code interface within affinity molecules is that effective affinity binders can be generated by using only 2 amino acids, tyrosine and serine (e.g. fibronectin type III domains that were developed using the Tyr/Ser binary-code interface demonstrated affinities to 3 different proteins of 5 to 90 nM (Koide, A., et al., Proc. Nat. Acad. Sci. 104, 6632-6637, herein incorporated by reference in its entirety)). In some embodiments, a nanomolar affinity level, which can be achieved in binary-code interface, is very effective in an affinity complex where the binding affinities are multiplied by the linkage of the affinity molecules. In some embodiments, the combination of a simplified binary-code interface library system and a cooperative affinity complex system greatly reduces the time and resources necessary to development high affinity and specific affinity complexes.
Detection Molecules
In some embodiments, the detection molecule is a protein fragment complementation system, wherein one protein fragment fused to one affinity molecule is complementary to another protein fragment fused to the other affinity molecule and complementation of protein fragments generates a measurable signal (protein fragment complementation assay). In some embodiments, the complementary protein fragments generate an active enzyme.
In some embodiments, the active enzyme is β-lactamase that can generate a colored product from a substrate such as nitrocefin, a fluorescent product from the substrate such as Fluorocillin Green, or a bioluminescent product (in combination with firefly luciferase) from a substrate such as Bluco (β-lactam-D-luciferin).
In some embodiments, the active enzyme is a luciferase that can generate bioluminescence from a substrate such as D-luciferin for firefly luciferase and coelenterazine luciferin for renilla and gaussia luciferases (ref).
In some embodiments, the complementary protein fragments generate a fluorophore such as green fluorescent protein, red fluorescent protein, or mutants of these proteins.
In some embodiments, the detection molecule is a donor or acceptor fluorophore that can be used in a Förster resonance energy transfer (FRET) assay. For example, one affinity molecule would be fused to the donor fluorophore via a linker and the second affinity molecule would be fused with the acceptor fluorophore via a linker. In some embodiments, the donor molecule is cyan fluorescent protein (CFP) and the acceptor molecule is yellow fluorescent protein. In some embodiments, the donor molecule is CyPet and the acceptor molecule is YPet. In some embodiments, the donor molecule is TagGFP and the acceptor molecule is TagRFP. In some embodiments, each affinity molecule fluorophore fusion protein contains domains that have complimentary affinity, wherein proximal donor and acceptor fluorophores are spatially oriented to allow efficient energy transfer. In some embodiments, the complimentary affinity domains are leucine zipper or other coiled-coil domains. In some embodiments, the complimentary affinity domains are affinity molecules designed for expressly this purpose.
In some embodiments, the donor and/or acceptor fluorophore is a small organic or inorganic molecule that is fused to a polypeptide or other molecule that has specific affinity for an expressed polypeptide fused to the affinity molecule. For example, fluorescein isothiocyanate can be conjugated to the end of the K-coil of a coiled-coil dimer that is complementary to the E-coil that is fused to the affinity molecule as it is expressed. In some embodiments, the fluorophore is conjugated to a chelated metal, such as nickel or copper, that binds a HisTag (4-10 histidines) fused to the affinity molecule as it is expressed. In some embodiments, the fluorophore is conjugated to streptavidin that binds to a 15 amino acid Nanotag fused to the affinity molecule as it is expressed.
In some embodiments, the fluorophore is conjugated to an affinity molecule that has affinity for the expressed affinity molecule (that has affinity for the target). In some embodiments, the affinity molecule to the target is fused with another affinity molecule that has affinity for the fluorophore or a conjugated fluorophore. In some embodiments, the organic fluorophore is a derivative of fluorescein, rhodamine, Alexa Fluors (Invitrogen), CyDye Fluors (GE Healthcare Life Sciences), DyLight Fluors (Dyomics GmbH), HiLyte Fluors (Anaspec) and the IRDye Near Infrared Fluors (Li-Cor).
In some embodiments, the inorganic fluorophore is a derivative of a rare earth metal chelate or cryptate (crown ether) such as lanthanium, terbium, samarium, dysprosium, or europium. In some embodiments, the fluorophore is a latex bead containing more than one fluorophore. In some embodiments, the fluorophore is a phycobiliprotein, such as R-phycoerythrin or allophycocyanin. In some embodiments, the fluorophore is a quantum dot.
In some embodiments, fluorophores are linked to either a NHS ester reactive group (reacts with ε-amine of lysine and the α-amine of the polypeptide N-terminal) or a maleimide reactive group (reacts with reduced sulfhydryl of cysteine). In some embodiments, labeling proteins non-specifically, especially small polypeptides can potentially interfere with their function. In some embodiments, it is important to demonstrate no loss of utility of the affinity molecule. In some embodiments, if the affinity molecule does not have a cysteine in the polypeptide sequence (such as an Affibody or fibronectin scaffold), a cysteine can be introduced at the C-terminal and specifically labeled with any maleimide fluorophore.
In some embodiments, the FRET assay is time-resolved (TR-FRET), wherein detection of fluorescence of the acceptor fluorophore is determined after a short delay (for example, 100 μsec) after excitation of the donor fluorophore, that is, the fluorescence of the donor has diminished significantly and the lifetime of the acceptor is sufficiently extended to measure its fluorescence.
In some embodiments, the donor detection molecule is a bioluminescent enzyme that can transfer resonance energy (BRET). For example, a luciferase enzyme typically generates light upon oxidation of its substrate, but can also transfer the energy to a fluorophore that is in proximity. In some embodiments, the bioluminescent enzyme is expressed as a fusion protein with one of the affinity molecules. In some embodiments, the bioluminescent protein is firefly, renilla, or gaussia luciferase. In some embodiments, the acceptor fluorophore is a fluorescent protein that is fused to an affinity molecule. In some embodiments, the acceptor fluorophore is an organic or inorganic
In some embodiments, the bioluminescent enzyme is fused to a polypeptide or other molecule that has specific affinity for an expressed polypeptide fused to the affinity molecule. For example, firefly luciferase can be fused to the K-coil of a coiled-coil dimer that is complementary to the E-coil that is fused to the affinity molecule as it is expressed. In some embodiments, the bioluminescent enzyme is conjugated to a chelated metal, such as nickel or copper, that binds a HisTag (4-10 histidines) fused to the affinity molecules it is expressed. In some embodiments, the bioluminescent enzyme is conjugated or fused to an affinity molecule that has affinity for the expressed affinity molecule (that has affinity for the target). In some embodiments, the affinity molecule to the target is fused with another affinity molecule that has affinity for the bioluminescent enzyme. In some embodiments, the acceptor fluorophore is protein expressed as a fusion protein with one of the affinity molecules such as GFP, YFP, and RFP. In some embodiments, the acceptor fluorophore is an organic fluorophore, inorganic fluorophore, or quantum dot.
In some embodiments, the donor detection molecule is a light induced singlet oxygen generating system and the acceptor detection molecule is a chemiluminescent system that is excited by singlet oxygen (luminescent oxygen channeling).
In some embodiments, the detection system is a dynamic light scattering assay, wherein the detection molecules are gold nanoparticles conjugate to affinity molecules with affinity for either reference of unknown affinity molecule. For example, a portion of gold nanoparticles can be conjugated with anti-His tag antibodies and another portion with anti-FLAG antibodies. Aggregation occurs in the presence of the target when both the affinity molecule expressing the His tag and the affinity molecule expressing the FLAG tag bind the target.
In some embodiments, the detection molecule is covalently linked to the affinity molecule via a flexible polymer such as a polypeptide (e.g. glycine/serine polypeptides), a nucleic acid strand, polyethylene glycol, and peptide nucleic acid (PNA) that has sufficient degree of freedom to allow the interaction of the secondary affinity molecules with the primary affinity molecules. In some embodiments, the affinity molecules are linked, either directly or linked via a suitable linker. The present invention is not limited to any particular linker group. Indeed, a variety of linker groups are contemplated, suitable linkers could comprise, but are not limited to, alkyl groups, ether, polyether, alkyl amide linker, a peptide linker, a modified peptide linker, a Poly(ethylene glycol) (PEG) linker, a streptavidin-biotin or avidin-biotin linker, polyaminoacids (e.g. polylysine), functionalised PEG, polysaccharides, glycosaminoglycans, dendritic polymers such as described in WO93/06868 and by Tomalia et al. in Angew. Chem. Int. Ed. Engl. 29:138-175 (1990), PEG-chelant polymers such as described in W94/08629, WO94/09056 and WO96/26754, oligonucleotide linker, phospholipid derivatives, alkenyl chains, alkynyl chains, disulfide, or a combination thereof.
In some embodiments the linker comprises a single chain connecting the detection molecule to the affinity molecule. In some embodiments, there are multiple linkers connecting the detection molecule to the affinity molecule. In some embodiments, a linker may connect multiple the detection molecules to the affinity molecule. In some embodiments, a linker attaches an additional functional portion to affinity molecule. In some embodiments, a linker may be branched, connecting more than two detection molecules to the affinity molecule. In some embodiments, the linker may be flexible, or rigid. In some embodiments, the linker of the present invention is cleavable or selectively cleavable. In some embodiments, the linker is cleavable under at least one set of conditions, while not being substantially cleaved (e.g. approximately 50%, 60%, 70%, 80%, 90%, 95%, 99%, or greater remains uncleaved) under another set (or other sets) of conditions. In some embodiments, the linker is susceptible to enzymatic cleavage (e.g. proteolysis). In some embodiments, the enzymatic cleavage is site specific (e.g. sequence specific). In some embodiments, the enzymatic cleavage is at a random site along the linker. In some embodiments, the enzymatic cleavage may occur at multiple random sites along the linker. In some embodiments, the linker is susceptible to cleavage under specific conditions relating to pH, temperature, oxidation, reduction, UV exposure, exposure to radical oxygen species, chemical exposure, light exposure (e.g. photo-cleavable), etc.
In some embodiments, detection molecules are prepared by any suitable method. In some embodiments, IgG antibodies are used as affinity molecules and can be linked via their reduced thiol groups, preferably using a crosslinking system from SoluLink. In some embodiments, one part of the anti-Fc IgG/Fab is labeled with MHPH (3-N-Maleimido-6-hydraziniumpyridine hydrochloride) and the other part with MTFB (Maleimido trioxa-6-formyl benzamide). In some embodiments, the hydrazine moiety of the MHPH-modified molecules react with 4-formylbenzamide of the MTFB-modified molecules to form stable bis-arylhydrazone-mediated conjugates. In some embodiments, alternative methods for crosslinking proteins, known to those skilled in the art, are utilized. In some embodiments, an oligonucleotide can be synthesized with chemically reactive moieties (for example, a maleimide) on each end that would react with the secondary affinity molecule. In some embodiments, each molecule could be conjugated to an oligonucleotide, one with a 3′ is free and the other with a 5′ free so that the two strands can be ligated. In some embodiments, any suitable methods to link the secondary affinity molecules would also be appropriate so long as the linker has flexibility to allow interaction of the secondary affinity molecules.
Target Molecules
In some embodiments, the target may be a protein, nucleic acid, carbohydrate, lipid, or other cell component. In some embodiments, the protein may be native or denatured, modified (such as glyco- or phosphoproteins), part of a complex with other proteins, nucleic acids, or lipids (such as a lipid micelle), or part of a cell (or cell debris). In some embodiments, the nucleic acid may be DNA (single or double stranded), RNA (message, ribosomal, transfer, transfer-message, small interfering, short hairpin, micro, piwi-interactive), or PNA (peptide nucleic acid). In some embodiments, the carbohydrate may be any number of polysaccharides including glycogen, cellulose, and chitin. In some embodiments, the lipid may be a polyglyceride, wax, steroid, vitamin, or other natural hydrophobic molecules. In some embodiments, the target may be native (natural) or recombinant, expressed, transcribed, or synthesized, purified or part of a crude mixture, and with or without an epitope tag.
In some embodiments, the target may be a synthetic molecule, organic or inorganic, particle, or polymer.
Assay Screening
In some embodiments, the method of screening for an affinity molecule includes a target molecule, a reference affinity molecule that is known to bind the target molecule with a known affinity, and an unknown affinity molecule. In some embodiments, the reference affinity molecule has affinity for a specific epitope on the target or an epitope tag added to the target. In some embodiments, the coding sequence (either DNA or mRNA) for the reference affinity molecule (when it is a protein) is fused to the coding sequence of the detection molecule (when it is a protein) and is expressed in the screening reaction using a cell-free translation. In some embodiments, fusions of affinity and detection molecules is expressed in a separate reaction, purified, and added to the screening assay. In some embodiments, affinity and detection molecules are chemically conjugated in a separate reaction, purified, and added to the screening assay.
In some embodiments, the affinity molecule is fused or conjugated to a secondary affinity molecule that has affinity for the detection molecule or the detection molecule may be fused or conjugated to a secondary affinity molecule that has affinity for the affinity molecule, and both the affinity and detection molecules are added to the screening assay. For example, a monobody that has affinity for a target protein is expressed with 10 histidine amino acids at the C-terminus and purified. This protein is mixed with a donor fluorophore conjugated to a nickel chelate complex that has affinity for the histidine tail and the entire complex is used in a FRET screening assay. This complex can be used for either the reference affinity molecule or the unknown affinity molecule, but not both in the same reaction.
In some embodiments, the unknown affinity molecule is prepared in the same way as the reference affinity molecule and added to the screening assay containing the target and the reference affinity molecules in a single reaction. In some embodiments, numerous unknown affinity molecules are prepared and added to a multi-well plate containing the target and the reference affinity molecules in a multiplexed screening assay. In some embodiments, a gene coding library of unknown affinity molecules are mixed with the target molecule and the reference affinity molecule (or the gene code for the reference affinity molecule) with its detection molecule in a cell-free extract capable of translating the gene library and the mixture is separated into microdroplets that are individual reactions. In some embodiments, a microfluidic device is used to create the microdroplets, merge and mix droplets, optimally heat the reactions (both translation and enzymatic assay if required), detect the output of the detection molecules (color, fluorescence, or bioluminescence light), sort and collect those droplets that exhibit a positive signal. In some embodiments, the microfluidic device amplifies the DNA in each droplet by polymerase chain reaction (PCR), or other amplification techniques, creating sufficient DNA to identify the gene sequence that codes for the positive binding reaction. In some embodiments, the microfluidic device (instrument) is a RainDance Technology instrument capable of creating, processing, and analyzing 3000 droplets per second, which would allow the screening of over 10 million reactions per hour (2.6×10 8 per day).
Epitope Mapping
In some embodiments, a target molecule is mixed with various combinations of affinity molecules known to have affinity for the target and, in association with their detection molecules, determined which combination produces a negative result indicating that both affinity molecules have affinity for the same epitope. For example, a gene library that has been screened for affinity molecules to a target molecule generates 25 positive clones, each of which is PCR amplified with both the detection molecule coding sequences and expressed in cell-free extract to generate the specific affinity molecules fused with a reference detection molecule and its complement detection molecule. Affinity molecule # 1 with its reference detection molecule is mixed with the target molecule and placed in each well of the first row (24 wells) of a 384 well plate to which affinity molecule # 2 with its complementary detection molecule has been added to well A 1 , affinity molecule # 3 with its complementary detection molecule has been added to well A 2 , and so on. The second row contains affinity molecule # 2 with its reference detection molecule, the third row with # 3 and so on. Positive signals indicate affinity binding of both affinity molecules to the target while negative signals indicate conflicting binding sites.
Systems and Kits
The present invention further provides systems and kits (e.g., commercial therapeutic, diagnostic, or research products, reaction mixtures, etc.) that contain one or more or all components sufficient, necessary, or useful to practice any of the methods described herein. These systems and kits may include buffers, detection/imaging components, positive/negative control reagents, instructions, software, hardware, packaging, or other desired components.
EXPERIMENTAL
Example 1
Exemplary Use
The first example demonstrates homogeneous FRET analysis and its implementation in a microfluidic device. A small His tag labeled protein target is mixed with HiLyte Fluor™ 488 conjugated mouse anti-His tag monoclonal antibody and a known anti-target antibody (IgG) labeled with HiLyte Fluor™ 555 in a cuvette tube and the fluorescence at ˜600 nm determined when exciting the solution at ˜500 nm (FRET). The same binding reaction is loaded into a microfluidic device set up to measure FRET fluorescence in the same way. Next, each component is loaded into individual compartments of the microfluidic device, droplets created, merged, and mixed in line, and the FRET fluorescence determined.
Example 2
Exemplary Use of Protein Fragment Complementation
The second example demonstrates utility of complementary renilla protein fragments fused to monobody affinity molecules via a peptide linker. A protein target is chosen for which the protein is available and the monobodies exist. The coding sequence for at least 2 monobodies is cloned into a cassette containing either the N-terminal renilla peptide or the C-terminal peptide, both using a ser/gly linker. The target protein, N-terminal renilla monobody, and C-terminal renilla monobody is mixed, added to renilla Luciferase Assay Reagent (Promega), and the bioluminescence measured using a luminometer. The same binding reaction is loaded into a microfluidic device set up to measure bioluminescence in the same way. Next, each component is loaded into individual compartments of the microfluidic device, droplets created, merged, and mixed in line, and the bioluminescence determined. Finally, a gene library of C-terminal (or N-terminal) renilla monobodies coding for various peptide sequences at the BC and FG domains of the monobody is screened for binding to the target using the known renilla monobody as the reference.
Example 3
Exemplary Use of BRET
The third example demonstrates utility of a BRET system for screening affinity molecules. A protein target is chosen for which the protein is available and the monobodies exist. The coding sequence for one of the monobodies is cloned into a cassette containing a renilla luciferase sequence and the coding sequence for the other monobody is coned into a cassette containing a red fluorescent protein (RFP). The target protein, renilla monobody, and RFP monobody is mixed, added to renilla Luciferase Assay Reagent (Promega), and the fluorescence of the RFP measured using a near infrared light detector. The same binding reaction is loaded into a microfluidic device set up to measure bioluminescence in the same way. Next, each component is loaded into individual compartments of the microfluidic device, droplets created, merged, and mixed in line, and the bioluminescence determined. Finally, a gene library of C-terminal (or N-terminal) renilla monobodies coding for various peptide sequences at the BC and FG domains of the monobody is screened for binding to the target using the known renilla monobody as the reference.
REFERENCES
The following references are herein incorporated by reference in their entireties:
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