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RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 11/281,212, filed Nov. 16, 2005, now U.S. Pat. No. 7,913,698; which application claims priority to U.S. Provisional Application No. 60/628,451, filed Nov. 16, 2004, and U.S. Provisional Application No. 60/648,036, filed Jan. 27, 2005, the entire contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to the treatment of a patient's lung, for example, the treatment of chronic obstructive pulmonary diseases (COPD). In particular this invention relates to systems, devices and methods for affecting lung volume reduction for the treatment of COPD, such as emphysema.
BACKGROUND OF THE INVENTION
Chronic obstructive pulmonary disease (COPD) includes chronic bronchitis and emphysema. COPD is generally characterized by airflow obstruction, which in particular limits the patient's air flow during expiration. Patients with chronic bronchitis have chronic cough with sputum production leading to obstructed expiration. In patients with emphysema, destruction of lung parenchyma can lead to loss of elastic recoil, reduced tethering of the airways, obstruction to expiration, and cough.
Lung function as well as quality of life in patients suffering with a COPD can be improved by reducing a patient's effective lung volume. One way to reduce effective lung volume is by surgically removing diseased portions of the lungs, both to promote expansion of the non-diseased regions, realign a patient's diagraph and to redirect inhaled air from diseased portions of lungs into healthier, better functioning lung regions. Surgery often results in effective volume reduction of about 15-30%, which may not be sufficient to cause an appreciable improvement in lung function. Also, conventional lung reduction surgery is traumatic, even when thorascopic procedures are employed.
Recently, bronchoscopic approaches for reducing effective lung volume have been proposed. See for example, U.S. Pat. Nos. 6,592,594, 6,679,264, 6,398,775 and 6,610,043; and U.S. Patent Publications 2003/0181922, 2004/0055606, and 2004/0047855. One challenge to achieving effective lung reduction, particularly in emphysematous lungs, is collateral ventilation or collateral pathways.
Accordingly, there is a need for devices, methods and systems for reducing effective lung volume without surgery, and also for reducing lung volume in the presence of collateral pathways. The present invention is directed to meeting these, as well as other, needs.
SUMMARY OF THE INVENTION
This invention relates to the treatment of a patient's lung, for example, the treatment of chronic obstructive pulmonary disease (COPD) and other conditions that can be treated by decreasing a patient's effective lung volume. In particular methods and devices of the invention relate to treatment for affecting lung volume reduction by delivering a thermal damaging agent to a targeted region of a patient's lung so that the region is essentially non-functional.
A method of treating a patient's lung includes delivering a thermal damaging agent to a targeted region of the patient's lung to raise the temperature of the tissue in the region sufficiently high to the extent that blood flow and air flow within the targeted region are terminated. Preferably the thermal damaging agent damages at least one of the group consisting of tissue defining at least in part an air sac of the targeted region, tissue of terminal bronchioles in the targeted region and collateral passageways in the targeted region. The method can also include occluding an airway of the lung through which the thermal damaging agent is delivered at a point proximal to where the thermal damaging agent enters the target region so as to isolate the region and prevent excursions of the thermal damaging agent to areas outside the target region.
One preferred method of treating a patient's lungs includes delivering a condensable vapor at a temperature above body temperature at atmospheric pressures to lung tissue of the target region, particularly the tissue defining at least in part an air sac within the patient's lung.
A device for delivering a thermal damaging agent to a targeted region of the patient's lung to raise the temperature of the lung tissue in the targeted region sufficiently high to render the targeted region essentially non-functional wherein neither blood flow nor air flow occurs within the region. The device for delivering a thermal damaging agent includes an elongate shaft having a proximal portion, a distal portion, and a thermal damaging agent delivering lumen extending within at least a distal portion of the shaft. The device has at least one discharge port in the distal portion of the elongate shaft in fluid communication with the thermal damaging agent delivering inner lumen. A thermal damaging agent generator is in fluid communication with the thermal damaging agent delivery lumen in the elongate shaft and is configured for generating a thermal damaging agent at a temperature above 40 ° C. to the tissue at the targeted region to render the region essentially non-functional. Preferably the device also includes an occluding member disposed on a distal portion of the shaft to occlude the airway passage proximal to the delivery location of the thermal damaging agent.
In one embodiment the device includes an elongate shaft having a proximal portion, a distal portion, and a vapor delivering inner lumen extending within at least the distal portion of the shaft. The device has at least one discharge port in the distal portion of the elongate shaft in fluid communication with the vapor delivering inner lumen configured to deliver condensable vapor to the target region. A condensable vapor generator is provided in fluid communication with the vapor delivering lumen of the elongate shaft for generating a condensable vapor at a temperature above 40° C. to thermally damage tissue at the targeted region sufficiently to terminate blood flow and air flow to the targeted region. Preferably the device also includes an occluding member disposed on a distal portion of the shaft. The delivered condensable vapor is generally about 40° to 80° C., and preferably is about 50° to about 60° C. The condensable vapor is delivered to the targeted region for a period of about 5 seconds to about 10 minutes, preferably about 5 seconds to about 10 seconds. Suitable liquids for forming the condensable vapor includes water based fluids and perfluorocarbon.
In addition to the treatment of COPD, other conditions can be treated, for example by applying the methods and devices described to pre-cancerous lesions, cancer tumors, or lung nodules. As will be recognized by those skilled in the art, reducing the total volume of a patient's lung, especially an emphysematous lung, can be an effective treatment for COPD.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A illustrates a method for treating a patient's lung embodying features of the invention.
FIG. 1B is an enlarged view of an air sac and alveoli within the patient's lung shown in FIG. 1A .
FIG. 2 is a longitudinal cross sectional view of the device shown in FIG. 2 .
FIG. 3A is a transverse cross sectional view of the device shown in FIG. 2 , taken along lines 3 A- 3 A.
FIG. 3B is a transverse cross sectional view of the device shown in FIG. 2 , taken along lines 3 B- 3 B.
FIG. 4 is an elevational view, partially in perspective, of a system embodying features of the invention.
FIG. 5A is an elevational view of a vapor generator connected to the device shown in FIG. 2 .
FIG. 5B is an elevational view of a vapor generator connected to the device shown in FIG. 2 which has a cartridge for storing vaporizable fluid.
FIG. 5C is an elevational view of a vapor generator connected to the device shown in FIG. 2 which is connected to a hand held operator or pistol grip handle.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a method for treating a patient's lung 10 embodying features of the invention that includes delivering a condensable vapor 12 to tissue defining an air sac or alveoli 14 within a patient's lung 10 at a temperature above body temperature, preferably about 40° C. to about 80° C., preferably about 50° C. to about 60° C. at atmospheric pressures, so as to damage the tissue of the air sac or alveoli 14 , the tissue of terminal bronchioles 16 and tissue of collateral passageways 18 . Such tissue damage renders the treated region non-functional in that the blood flow and air flow in the treated region is terminated. The treated region will no longer inflate.
The method includes delivering the condensable vapor through an airway 20 of the lung to the targeted lung region. Preferably the airway 20 is a bronchial passageway such as segmental bronchi, and most preferably a sub segmental bronchi 20 .
The condensable vapor 12 serves to rapidly heat the targeted lung region as the vapor 12 is delivered and induces tissue collapse, shrinkage, neointima hyperplasia, necrosis and fibrosis (collectively referred to herein as “bioeffects”) of the targeted lung region. Such bioeffects render the target lung region non-functioning.
The method may also include applying a vacuum to the targeted region after delivery of the condensable vapor to further supplement tissue contraction and collapse caused by introduction of the condensable vapor 12 . The vacuum generated in the targeted region is about 1 to about 50 mm Hg, preferably about 10 to about 30 mm Hg to effectively collapse the targeted region. The vacuum may also facilitate aspiration of any residual vapor or liquid.
In general the vapor is applied into the targeted region through an airway for anywhere from 5 seconds to 10 minutes or longer. Preferably the condensable vapor is delivered for a short period of time, about 5 seconds to 10 seconds. Because tissue heating and the resulting damage is rapid using energetic vapor, short vapor application times are preferred. In longer procedures, less vapor may be used to cause gradual tissue bioeffects or to treat larger regions or volumes of tissue. Separate procedures may be utilized for separate regions to be treated.
The condensable vapor 12 maybe generated from a liquid, for example, sterile water or other fluids such as perfluorocarbons, having relatively high liquid-gas phase-change temperatures, i.e. boiling points, preferably temperatures well above body temperature. In addition, preferably the condensable vapor 12 is at a temperature sufficient to increase the temperature of the surrounding lung parenchyma to cause damage, for example, above at least 40° C.
In one method of the invention the condensable vapor 12 additionally includes a detectable substance, such as a dye, preferably a biocompatible dye, to detect movement of the condensable vapor 12 and the affected lung regions. Alternatively or in conjunction with the visually detectable substance, diagnostic ultrasound, endoscopic and other conventional visualization techniques are used to monitor the vapor treatment and resulting tissue effects during and after treatment.
In another method embodying features of the invention, the condensable vapor 12 is delivered with microparticulates. Suitable microparticulates include talc, calcium carbonate, antibiotics such as tetracycline and other penicillin derivates, or other particulate substances which induce fibrosis or cause necrosis of the lung tissue.
In another method embodying features of the invention the condensable vapor 12 includes a treatment agent such as an anesthetic or painkillers to alleviate patient discomfort and pain during the treatment. A painkiller, such as lidocane in powder or liquid form, preferably is used or mixed with a condensable vapor 12 . Alternatively, pain killers may be delivered to the entire lung, or just to the targeted lung region. Patient preparation with pain medication before, during, and after the procedure is preferred in order to allow treatment using the present invention without the need for general anesthesia.
In another method embodying features of the invention helium or carbon dioxide is delivered in addition to the vapor 12 to lower the temperature of the vapor 12 .
A method of the invention includes occluding the airway of a lung proximal to the area where the condensable vapor 12 is delivered. In some embodiments, to prevent condensable vapor from entering and damaging adjacent airways and lung regions, the adjacent airways are filled with a fluid, such as saline. Airways leading to untargeted lung regions may be obstructed to prevent vapor flow therein.
In one method embodying features of the invention high intensity focused ultrasound (HIFU) energy is delivered to damage lung tissue such as the tissue of an air sac or alveoli in the lung. Preferably suitable ultrasound transducers that are capable of delivering high intensity. focused ultrasound (HIFU), generally between about 100-10,000 W/cm 2 at a focal spot.
The HIFU energy is delivered in amounts sufficient to cause contraction of lung tissue. Because HIFU can be tightly controlled, the ultrasound energy can be specifically targeted to the epithelium, smooth muscle layer, or collagen layer. Delivery of the HIFU energy can also serve to initiate a healing response (including neointima hyperplasia) which further serves to occlude the passageway. The method can include a wave guide to direct the HIFU sound waves to the intended treatment site. Additionally a vacuum may be applied prior the HIFU to draw down the airway or air sacs. Alternatively the vacuum may be applied after delivery of the HIFU energy as in the previously discussed embodiment to further supplement tissue contraction and collapse of the terminal bronchioles, air sacs and collateral passageways caused by introduction of the ultrasound energy.
In another embodiment, an ultrasound absorptive material, such as a liquid or gel, can be eluted into the airway of the lung. The absorptive material is heated by the HIFU energy in order to thermally damage the surrounding tissue, resulting in contraction of the airway and or neointima hyperplasia, which will occlude the airway and or damage the air sacs of the lung.
In an alternative embodiment, RF energy can be delivered to a desired location within a patient's lung to damage lung tissue but this usually requires a conductive fluid in contact with the lung tissue for effective ablation.
FIG. 2 depicts a system 22 embodying features of the invention including an elongate shaft 24 having a distal portion 26 and a proximal portion 28 . FIG. 2 is a longitudinal cross sectional view of the elongate shaft 24 and FIGS. 3A and 3B show transverse cross sectional views of the elongate shaft along the lines 3 A- 3 A and lines 3 B- 3 B shown in FIG. 2 . The elongated shaft 24 has at least one discharge port 30 in the distal portion 26 of the shaft configured to discharge condensable vapor 12 and a vapor delivering lumen 32 disposed within the elongate shaft 24 in fluid communication with the discharge port 30 . A vapor generator 34 is connected to the lumen 32 of the elongate shaft.
The elongate shaft 24 also contains a vacuum lumen 36 which is configured to be connected to a vacuum source for application of a vacuum through vacuum port 38 in the distal portion 26 of the elongate shaft.
The elongated shaft 24 is also provided with an inflation lumen 40 which leads to the inflation port 42 . Port 42 opens to the interior 44 of the inflatable balloon 46 which is secured to the distal portion 26 of the shaft. The inflation device 48 may be a conventional syringe. The occluding member 46 is preferably expandable, compliant, and is configured to prevent vapor flow proximal to the location of the member. Suitable balloon materials include silicone or latex. The exterior of the working surface of the inflatable balloon 46 is preferably provided with a knurled or roughened surface to better engage the airway walls and prevent recoil when the condensable vapor is delivered to the target location.
A venting system may be included with the device to ensure that high pressure does not exceed suitable limits. The venting system includes a venting lumen 50 in the shaft 24 which is in fluid communication with the port 52 in the distal end of the shaft 24 . The venting mechanism can be a pressure actuated relief valve 54 .
The device 22 also includes a temperature sensor 56 , for example a thermocouple, located on the distal portion 26 of the elongate shaft 24 to monitor the surrounding temperature. When the temperature is too high, the lung region is brought back to normal temperatures with a lavage or washout procedure to facilitate removal of residual vapor.
The device 22 preferably includes a pressure sensor 58 on the distal portion 26 of the elongate shaft 24 to detect pressure within the targeted lung region. The pressure sensor 58 communicates with a pressure gauge 60 on the proximal portion 28 of the elongate shaft 24 . The pressure sensing system may be tied in with the venting system to ensure that preset pressure limits are not exceeded during vapor delivery. Over inflation of the target region could lead to air leaks and tears in the lung pleura.
A suitable flow meter (not shown) may be included to monitor vapor flow to the targeted region of the patient's lung.
As shown in FIG. 4 the elongate shaft 24 is configured to be delivered through the working channel (not shown) of an endoscope 62 , preferably a bronchoscope. The working channel of the endoscope 62 is preferably between about 1.5 mm and 3.5 mm. The endoscope 62 is connected to an endoscope controller 64 and an endoscope monitor 66 . Preferably, the distal portion 26 of the elongate shaft 24 is flexible to facilitate advancement of the elongate shaft in the working channel of the endoscope 62 , while the proximal portion 28 is sufficiently rigid for good pushability of the shaft through and out of a distal opening of the endoscope. The distal portion 26 of the shaft 24 is about 1-6 French, the occluding balloon when inflated is larger than the working channel of the endoscope and is typically about 8 French. A suitable endoscope is the Olympus LF-TP bronchoscope.
Alternatively or in addition to the use of the occluding member 46 , airways adjacent the delivery airway can be obstructed, for example, with a fluid such as saline. The fluid in the adjacent airways prevents condensable vapor 12 from entering into other lung regions which are not targeted for treatment and prevents damage of the adjacent regions.
Preferably the vapor generator 34 , as shown in FIG. 5A , is external to the elongate shaft 24 and stores the liquid supply. The vapor generator 34 has an outer housing 72 which houses internal structures including a liquid chamber 74 and an inner vapor conduit 76 . Liquid may be loaded directly into the liquid chamber. The inner vapor conduit 76 extends from the liquid chamber 74 of the vapor generator 34 to the proximal portion 28 of the first lumen 32 and receives the condensable vapor 12 from the liquid chamber 74 a via an inlet port 78 . The vapor generator 34 couples to the elongate shaft 24 via a luer fitting or similar mechanism. The liquid chamber 74 has heating elements such as resistive heating elements, or a RF heater or the like for vaporizing liquid inside the liquid chamber to a condensable vapor. When the liquid is vaporized, the vapor travels from the liquid chamber 74 through the inner vapor conduit 76 and exits into the proximal portion of the vapor lumen 32 of the elongate shaft 24 of the device.
Alternatively, as shown in FIG. 5B the vapor generator includes a cartridge compartment 80 which receives a cartridge 82 in fluid communication with the lumen 32 and containing a predetermined amount of liquid for vaporizing. The cartridge 82 is configured to preferably snap-fit into the compartment 80 . When the vapor generator 34 is activated the fluid in the cartridge 82 is heated to a vapor. The condensable vapor 12 is then delivered to the proximal end of the first lumen 32 . A predetermined volume or amount of vapor pressure to be delivered to a patient's lung 10 can be determined or calculated based on diagnostic evaluations or parameters of the patient before the treatment procedure, such as forced expiratory volume (FEV) or other lung function and capacity indicators.
In one embodiment, the vapor generator 34 , as shown in FIG. 5C has an inner vapor conduit 76 which extends into a generator tube 84 . The generator tube 84 connects to a pistol grip handle 86 which is configured to couple to the proximal portion 28 of the elongate shaft. The pistol grip handle 86 can be used to activate heating of the vapor 12 within the liquid chamber 74 of the vapor generator 34 . The condensable vapor travels from the vapor generator 34 to the pistol grip 86 and into the elongate shaft 24 .
Alternatively, the vapor generator 34 can be disposed within the elongate shaft 24 . The heating elements, for example an RF electrode or emitter such as a helical coil, may be embedded within the wall of the shaft, surrounding the lumen 32 . The heater may be used as an alternative to the vapor generator 34 or to augment or further control the temperature of the vapor leaving the discharge port 30 from lumen 32 .
Preferably, the elongate shaft 24 of the device 22 is heat insulated to avoid overheating of the elongate shaft 24 inside the endoscope 62 . In one embodiment the elongate shaft 24 contains a liquid lumen (not shown) and a cooling fluid is delivered within this lumen to prevent overheating.
The condensable vapor 12 is a substance which is capable of rapidly heating a region of the lung to render the target region non-functioning where there is little or no blood flow or air flow within the region. Suitable condensable vapors 12 are selected from the group consisting of condensable vapors from aqueous based fluids, for example, sterile water, saline, contrast fluid, and other fluids such as perfluorocarbons, liquid antibiotics, and other liquids having high liquid-gas phase-change temperatures, i.e. boiling point, preferably above body temperature. In addition preferably the condensable vapor 12 is at a temperature sufficient to increase the temperature of the tissue at the target site to cause tissue damage.
In another embodiment of the invention the condensable vapor 12 includes a detectable substance, such as a dye or a biocompatible dye, to allow the physician to visually track progress of treatment and which lung regions have been treated. Alternatively or in conjunction with the visually detectable material, diagnostic ultrasound, endoscopic and other conventional visualization techniques are used to monitor the condensable vapor treatment and resulting tissue effects during and after treatment.
In yet another embodiment the condensable vapor 12 comprises a treatment agent such as a pain-numbing substance or painkillers to alleviate patient discomfort and pain during the treatment. A painkiller, such as lidocane in aqueous powder or liquid form, preferably is used or mixed with a condensable vapor 12 . Alternatively pain killers are delivered to the entire lung, or the targeted lung region. Preferably patient preparation with pain medication before, during, and after the procedure is preferred in order to allow treatment using the present invention without the need for general anesthesia. The device can include a drug delivery lumen in fluid communication with a drug delivery port in the distal portion of the elongate shaft. Painkillers or other drugs can be delivered to the desired area through the optional drug delivery lumen.
In yet another embodiment the elongate shaft 24 of device 22 has a helium or carbon dioxide delivery lumen (not shown) for delivering helium or carbon dioxide in addition to the vapor 12 to lower the temperature of the condensable vapor 12 .
While particular forms of the invention have been illustrated and described herein, it will be apparent that various modifications and improvements can be made to the invention. Moreover, individual features of embodiments of the invention may be shown in some drawings and not in others, but those skilled in the art will recognize that individual features of one embodiment of the invention can be combined with any or all the features of another embodiment. Accordingly, it is not intended that the invention be limited to the specific embodiments illustrated. It is therefore intended that this invention be defined by the scope of the appended claims as broadly as the prior art will permit.
Terms such as “element”, “member”, “device”, “section”, “portion”, “component”, “means”, “steps” and words of similar import when used herein shall not be construed as invoking the provisions of 35 U.S.C §112(6) unless the following claims expressly use the terms “means” or “step” followed by a particular function without reference to a specific structure or action. All patents and all patent applications referred to above are hereby incorporated by reference in their entirety. | This invention relates to the treatment of a patient's lung, for example, a lung exhibiting chronic obstructive pulmonary disease (COPD) and in particular to methods and devices for affecting lung volume reduction, preferably for achieving acute or immediate lung volume reduction following treatment. The lung volume reduction is effected by delivering a condensable vapor at a temperature above body temperature to the desired regions of the patient's lung to damage tissue therein. Blood flow and air flow to the damaged tissue region is essentially terminated, rendering the target region non-functional. Alternative energy sources may be used to effect the thermal damage to the lung tissue. | 0 |
TECHNICAL FIELD
This invention relates to a propeller pitch control apparatus for hydraulically operated variable pitch systems.
BACKGROUND OF THE INVENTION
Variable pitch propellers are employed in various applications including turboprop engines. Turboprop engines have proven to be desirable for aircraft because of high reliability and fuel efficiency. A turboprop engine uses a gas turbine engine to provide shaft power that rotates propeller blades. The blades provide thrust to propel an aircraft. The thrust is varied by changing the pitch of the blades. Forward thrust is achieved by rotating the blades to a positive angle. At cruise, the blades are adjusted to the intermediate positive position reducing engine torque and saving fuel. During landings, the blades are rotated to a negative angle to provide reverse thrust.
Propeller pitch for hydraulic applications is generally controlled through three devices: a propeller pitch control, a propeller governor, and a feathering valve. The propeller pitch control is operated through the use of a power lever connected to pitch control cam. The propeller pitch control allows the operator to adjust the blade pitch during ground operation, typically between the reverse and flight idle positions. The propeller governor automatically adjusts the blade pitch, typically between the flight idle and full power positions, to maintain a predetermined engine speed. The governor uses flyweights to mechanically start a chain reaction when engine speed increases above the predetermined speed by opening a pilot valve plunger to increase blade pitch. This increases engine load which will decrease engine speed back to the predetermined speed. Finally, the feathering valve is essentially a safety device to mechanically position the blade in the full feather position during emergencies. The device is a mechanically operated valve that, when opened, dumps the oil from the pitch control system and adjusts the blades to the full feather position.
Typically these systems operate a single acting propeller pitch control piston. In a single acting pitch system, the hydraulic fluid supplied by the prop governor or the pitch control is fed through a beta tube to bias the propeller pitch control piston against a spring. For a dual acting piston, two sources of oil are typically controlled by the same types of mechanisms mentioned above or other mechanical actuators connected to a spool type valve. These oil supplies are typically fed to the pitch control piston and react against each other to move the control piston.
While hydraulic pitch control systems are well known in the art and have good reliability, they require heavy and complicated actuation devices and associated linkages. Another problem is that the governor requires speed error to adjust the blade pitch resulting in fluctuations of blade pitch during transient conditions. Still another problem is that the pitch control cam requires large mechanical loads to operate.
Accordingly, a need exists for a pitch control device that can vary blade pitch from the reverse position to the feather position with a fewer number of components, that can control blade pitch during flight with minimum speed error, and that does not require great mechanical loads to operate.
SUMMARY OF THE INVENTION
The invention is an improvement to a hydraulically controlled variable pitch control assembly that includes a follow-up servo piston operated by a FADEC (Full Authority Digital Engine Control) controlled stepper motor. Thus, the propeller pitch can be controlled by the FADEC similar to existing fuel control systems by using data from various sensors that indicate flight conditions and engine speed. This will allow the FADEC to control the change in propeller pitch through the follow-up servo piston, and thus, greatly decrease the overall system weight by removing the propeller governor, the pitch control and the feathering valve. The present invention also eliminates fluctuations during transient conditions attributed to the flyweights in the propeller governor and removes the mechanical loads associated with the pitch control cam.
Accordingly, it is an important object of the present invention to provide a highly simplified propeller pitch control system directly responsive to low power electrical control signals as may be generated by a full authority digital engine control. The control signals control opposite directions of motion of a hydraulic servomotor which mechanically-positions a hydraulic power servo control valve. Movement of the power servo control valve then ports fluid in and out of the propeller pitch actuator.
These and other objects and advantages of the present invention are specifically set forth in or will become apparent from the following detailed description of a preferred embodiment of the invention, when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a perspective view of a turboprop engine employing a pitch control device according to the present invention.
FIG. 2A is a cross-sectional view of a follow-up servo piston propeller pitch controller according to the present invention.
FIG. 2B is a perspective cutaway of a single action propeller pitch control piston operated by the apparatus in FIG. 2A.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, FIG. 1 shows a turboprop engine 10 including a core engine 12 and a variable pitch propeller assembly 15. The core engine 12 is comprised of an air inlet 20, a compressor section (not shown), a combustor section (not shown), and a turbine section (not shown), all assembled in a flow series relation. Journaled to the forward end of the core engine 12 is the variable pitch propeller assembly 15 comprising a plurality of propeller blades 18 circumferentially disposed about and radially extending from a propeller hub 16. In operation, the core engine 12 provides shaft power to the propeller assembly 15 by compressing air in the compressor section, combusting the compressed air with fuel in the combustor section and expanding the combustion products in the turbine section to provide shaft power. The shaft power is used to rotate the blades 18 about axis 17 to move ambient air and provide thrust for an aircraft (not shown).
Referring to FIG. 2A, a full authority propeller pitch control 14 is comprised of a hydraulic servo motor in the form of a double-acting, linear servo piston 40 that is translated within a housing 60 by hydraulic fluid supplied from a pump 70 to opposing chambers 62, 64. A low power pilot control valve, in the form of a pilot sleeve 84, is responsive to a stepper motor 82 and a full authority digital engine control (FADEC) 80 to control the movement of the servo piston 40. Integral to the servo piston 40 is a first bored rod or shaft 50 that extends through one side of the housing 60 and receives one end of a hollow beta tube 32 described in greater detail below. The shaft 50 has a blind bore presenting a chamber 63 communicating with chamber 62 through passage 52, and has an end section 51 that has a smaller diameter that is approximately equal to the diameter of the beta tube 32. The diameter of end section 51 must be great enough to allow the beta tube to slide relative thereto.
Extending from the opposite face of piston 40 is a second rod or bored shaft 42 with a duct 58 extending to an exhaust port 56. A hole 54 allows fluid to flow between duct 58 and chamber 64. Shafts 50 and 42 are sized such that the reaction area of piston 40 subject to the fluid pressure from chamber 64 is greater than the area of piston 40 subject the opposing fluid pressure from chambers 62 and 63 combined.
The pump 70 continuously supplies the hydraulic fluid which can be recirculated through a relief valve 72 if the pressure in the housing 60 becomes too great. The hydraulic fluid from pump 70 is supplied to chamber 62 through conduit 74. The fluid flows through an orifice 66 in a flow restricting passage through piston 40, and passes between chambers 62 and 64. The fluid dumps from the housing 60 into a low pressure return such as the sump of a surrounding gearbox 73 (depicted by dashed lines for simplicity) through the exhaust port 56. The fluid also exits to low pressure return from the interior 34 of beta tube 32 through an opening 36. Pressurized fluid is supplied into the interior 34 of tube 32 through opening 38. Reduced diameter land 51 acts as a power servo control valve in covering and uncovering openings 36, 38 in their communications with the low pressure return gearbox 73 and pressurized bore 63, respectively.
FIG. 2B illustrates a conventional propeller pitch control actuator 19 as may be utilized in conjunction with the control contemplated by the present invention. The blades 18 (only one shown in FIG. 2B) are fixed to rotate with a rotating blade housing 27 about the hub centerline 17. The blade 18 can also rotate or swivel within the housing 27 about the blade pitch centerline 29 to change the blade pitch. An eccentric roller 23 is attached to the blade 18 on the periphery of the bottom of the blade 18 in offset relation to the pitch axis of rotation 29, and is moved by a pitch control piston 21. The pitch control piston 21 slides in a back and forth motion within the housing 27 moving the disk 23 to rotate blade 18. The pitch control piston 21 is biased on one side by a spring 22 and on the other by a chamber 24 that fills with hydraulic fluid. The piston also contains a bore 28 carrying beta tube 32 that is firmly secured to piston 21 to both rotate with the housing 27 and translate with piston 21. The hydraulic fluid is supplied from the beta tube interior 34 through a hole 30 to the piston bore 28 and then through a hole 26 to the hydraulic chamber 24. The pitch control piston 21 movement is thus dependent on the supply of hydraulic fluid to chamber 24 to react against the spring 22.
In operation, the propeller variable pitch control 14 is in a balanced or in a stationary state when the hydraulic exhausts 56 and 36 are partially covered by pilot valve sleeve 84 and the control valve 51 respectively. Fluid flow into chamber 64 through orifice 66 and subsequent discharge through port 56, maintains a pressure in chamber 64 which is lower than that in chamber 62. In this state, servo piston 40 is stationary because the product of the associated pressure times exposed piston area in chamber 64, is equal to the product of associated higher pressure times exposed piston area in chambers 62 and 63. The pitch control piston 21 is stationary because the product of pressure times area in chamber 24 is equal to the spring 22 force.
When changing blade pitch, a leftward movement of the pitch control piston 21 as depicted in FIG. 2B positions the blade 18 at a more positive pitch angle. In the preferred embodiment, the FADEC 80 increases blade pitch by signalling the motor 82 to move the pilot control sleeve 84 in the leftward direction in FIG. 2A. This exposes more of port 56 to the gearbox 73 and increases the flow therethrough. The increased flow through hole 56 decreases the pressure in chamber 64 because the area of opening of port 56 is now greater than the cross-sectional area of orifice 66. The pressure in chambers 62 and 63 then forces the servo piston 40 in the leftward direction until the port 56 is again partially covered by the pilot control sleeve 84. Once the port 56 is partially covered again, the pressure in chamber 64 increases and the servo piston 40 becomes stationary at the new location.
This leftward motion of servo piston 40 causes shaft rod 50 and associated power servo control valve 51 to cover opening 38 and to uncover opening 36. This allows rapid fluid dump from the beta tube 32 to the gearbox 73. The loss of hydraulic fluid from the beta tube 32 decreases the hydraulic pressure in hydraulic chamber 24, allowing spring 22 to push the pitch control piston 21 and the attached beta tube 32 leftwardly until hole 36 is partially covered and hole 38 is partially exposed again. Once the holes are partially exposed again, the product of pressure and area in chamber 24 again equals the force of spring 22, and piston 21 becomes stationary at the new location. As explained earlier, the leftward movement of piston 21 moves disk 23 which rotates blade 18 into an increased blade pitch.
In emergency situations the blade 18 can be forced into a feather position by dumping the hydraulic fluid from chamber 24 and allowing the spring 22 to position the piston 21 in its furthest leftward position. Spring 92 loads pilot sleeve 84 against stepper motor 82.
In a similar manner, the FADEC 80 decreases blade pitch by signalling the motor 82 to move the pilot sleeve 84 in the rightward direction, further covering port 56. This movement increases the pressure in chamber 64 to shift the servo piston 40 rightwardly until the port 56 is re-opened. The rightward motion of servo piston 40 causes shaft 50 to further uncover opening 38 while further covering the opening 36. This rapidly increases the amount of hydraulic fluid entering the beta tube 32 which increases the pressure in chamber 24. The hydraulic fluid shifts the pitch control piston 21 and the beta tube 32 rightwardly until openings 38 and 36 are both partially covered again. The rightward movement of the pitch control piston 21 also moves the disk 23 to decrease the blade 18 pitch angle.
The FADEC 80 can be programmed to adjust blade pitch similarly to when controlling fuel supplies, by using various flight control parameters. Using the FADEC 80 will avoid the overrunning required in prior art pitch control devices.
Accordingly, it will now be apparent that very low power electrical signals can readily shift pilot valve sleeve 84. This controls fluid flow in servo motor 14 to drive the latter in opposite directions to generate the much higher forces necessary to position the servo control valve (the reduced diameter section 51 of the shaft 50) to correspondingly drive the pitch actuator 19. The integral configuration of the double-acting servo motor 14 with its opposed rods or shafts provide a high compact, lightweight, economical pitch control.
While the present invention has been depicted and described by reference to a particular embodiment in order to explain the invention, no limitation upon the invention is implied by such reference. It is understood that various modifications may be made to the preferred embodiment without departing from the scope of the invention. For instance, one skilled in the art would understand that the invention is readily suitable for use with a double-acting propeller pitch actuator rather than the single acting actuator 19 illustrated. The invention is intended to be limited only by the spirit and scope of the appended claims. | A control for a hydraulic propeller pitch actuator includes a low power pilot valve responsive to digital electronic input signals to control movement of a hydraulic servomotor driving a higher power servovalve. Negative feedback motion is delivered from the servomotor to both the pilot valve and the servovalve. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This Application claims the benefit of the U.S. Provisional Application No. 60/480,798 filed Jun. 24, 2003, which is hereby incorporated by reference in its entirety.
BACKGROUND
[0002] The claimed inventions relate generally to boat to trailer couplings, and more particularly to watercraft docking systems that include automatic bow alignment and capturing operation.
BRIEF SUMMARY
[0003] Disclosed herein are various exemplary watercraft docking systems including a boat attachable portion that couples and aligns to a trailer portion. Detailed information on various example embodiments of the inventions are provided in the Detailed Description below, and the inventions are defined by the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] [0004]FIGS. 1A and 1B show an exemplary boat docking system with self-alignment and latching in a capture state.
[0005] [0005]FIGS. 2A and 2B shows the boat docking system of FIG. 1 in an entry state.
[0006] [0006]FIG. 3A and 3B shows the boat docking system of FIG. 1 in a release state.
[0007] [0007]FIG. 4 illustrates a capture and release control mechanism utilizing mechanical operation.
[0008] [0008]FIG. 5 illustrates a capture and release control mechanism utilizing electrical operation.
[0009] [0009]FIG. 6 illustrates conceptually the locations of various docking components relative to a trailer.
[0010] [0010]FIG. 7 depicts a capturable head having a collapsible profile.
[0011] [0011]FIGS. 8A, 8B and 8 C depict a capturable head having external pawls and an internal motor cavity.
[0012] [0012]FIG. 9 depicts a bow mountable portion having a motor included within a capturable head external to the hull of a boat.
[0013] [0013]FIG. 10A conceptually illustrates a bow mountable portion having a retractable head mechanism.
[0014] [0014]FIG. 10B conceptually illustrates a bow mountable portion having a head designed to retract into a recess in a hull.
[0015] Reference will now be made in detail to various systems incorporating a bow mountable portion capturable in a receiver or trailer portion which may include some more specific embodiments of the claimed inventions, examples of which are illustrated in the accompanying drawings.
DETAILED DESCRIPTION
[0016] Many persons have come to enjoy the activity of boating on many of the world's lakes and waterways. To transport watercraft from one's home to a water site, a trailer is used, which is generally towed behind a vehicle using roadways. To launch the watercraft a ramp is typically used. The trailer is backed onto the ramp sufficiently to cause the watercraft to begin to float At that point, a pilot enters the watercraft cockpit, while an assistant locates near the winch or other release mechanism. When the watercraft is released from the trailer, the pilot drives the motor in reverse to separate the craft from the trailer, after which the trailer and towing vehicle may be parked. The assistant might then enter the craft from a dock or by wading or swimming to the craft.
[0017] To retrieve the craft the process is substantially reversed. The trailer is backed into the water to a certain position. The pilot then carefully guides the craft over the trailer, following which the assistant latches and winches the craft onto the trailer. This procedure can be especially difficult in rough or choppy waters, as the craft may be jostled about in relation to the trailer. Of additional note, in both of the above procedures, the securing and releasing of the craft may be a two-person operation, however one person might perform the procedure if he doesn't mind wading or swimming between the trailer and the released craft.
[0018] Referring now to figures 1 A and 1 B, an exemplary boat docking system with self-alignment and latching is depicted in a captured position. That system is divided into a boat attachable portion and a trailer attachable portion. The boat attachable portion includes a protruding head 1 which protrudes from the hull 11 of the boat's bow. Head 1 may be machined from a unitary block of metal, or may be assembled as several rigid or semi-rigid parts. Head 1 might be machined from a metal, such as aluminum, from a plastic, such as Delrin® or nylon, or other composite materials. In this example, head 1 takes on an arrowhead shape, the head coming to a rounded point and having corners extending to provide latching surfaces 18 a and 18 b . Also in this example, a shaft 2 passes through a guide 3 , which maintains the shaft in a forward orientation, the forward direction being relative to the boat. A shaft end 4 provides a lateral securement, which might be through a collar or stop arrangement within hull 11 , which is not shown. Further in this example, the head 1 is attached to shaft 2 , which shaft is in rotatable communication with a swivel or bearing device located in guide 3 . Guide 3 may incorporate a unique mounting bracket specifically and uniquely designed for the particular contour of a receiving craft's bow.
[0019] The trailer portion includes two guides, 5 a and 5 b , which in this example provide several functions. First, the interface between guides 5 a and 5 b form a separation to enclose the protrusion of the boat portion, in this example shaft 2 . Second, guides 5 a and 5 b provide guidance for a forward moving head, whereby the head 1 may be directed to the separation between the guides. In this example, guides 5 a and 5 b are shaped as striking plates, although other shapes may be similarly utilized. Third and lastly, the guides 5 a and 5 b prevent head 1 from moving backward out of the capture position by physical holding force on latchable surfaces 18 a and 18 b . Further in this example, the ends of guides 5 a and 5 b may be profiled to provide contact over a wider area of surfaces 18 a and 18 b , which may be done to inhibit wear and generally provide strength. Also in this example, guides 5 a and 5 b are rotatably mounted to axial members 7 a and 7 b , which in this case are rigid cylinders, coupled by rotating sleeves 6 a and 6 b.
[0020] Referring now to figure 1B, the separation between guides 5 a and 5 b is generally vertical, permitting head 1 to move up and down while remaining captured between the guides. In this way, a boat is permitted some freedom to move, which may reduce stress of the various components and assist in properly seating of the boat to the trailer when the trailer is pulled from the water.
[0021] Guides 5 a and 5 b might be fashioned from plate metal, for example stainless steel. Alternatively, guides 5 a and 5 b may be lined with a substantially frictionless material, for example Dehrin®, which may improve resistance to marring and denting and assisting the aligning movement of the head 1 into the separation between guides 5 a and 5 b . That lining may also inhibit impact damage to the hull 11 of the watercraft, should the hull impact guides 5 a and 5 b.
[0022] Axial members 7 a and 7 b are mounted to a base 8 , which maintains the position of axial member 7 a and 7 b relative to each other. A top brace 12 is provided, in this example, to stiffen the system and reduce stress at the lower portions of axial members 7 a and 7 b . Brace 12 may be set at a height to restrict vertical travel of the head 1 , shaft 2 or the boat's bow from vertically exiting the receiver, and may further be lined with a relatively soft material to prevent marring, for example nylon. The vertical position of guides 5 a and 5 b are held in place by securable stops 14 a and 14 b . In this example, gravity is utilized to keep the guides 5 a and 5 b from moving upward, although additional stops may be installed if desired. Also in this example, the vertical position of guides 5 a and 5 b may be adjusted by moving stops 14 a and 14 b up or down, as desired. A tensioning component 15 is included to provide a convergent force between guides 5 a and 5 b , by which the guides are brought together in a restricted separation. Guide stops 10 a and 10 b , attached by rods 9 a and 9 b , are provided to maintain a selected separation between guides 5 a and 5 b . Rods 9 a and 9 b may provide adjustment of guide stops 10 a and 10 b , by which guides 5 a and 5 b may be brought to contact with hull 11 , providing further securing and/or clamping of the boat to the receiver in the capture position. In this way these components of the trailer portion act as a receiver for the head 1 and boat generally.
[0023] Guide 3 is configured to permit shaft 2 and head 1 to rotate into a capture position and a release position. FIGS. 1A and 1B show the head in a horizontal capture position, while FIGS. 3A and 3B show the head in a release, or vertical position. Referring now to FIGS. 3A and 3B, head 1 has a profile larger than the separation between guides 5 a and 5 b in one direction, and smaller in another direction. With head 1 in release position, i.e. in a position whereby the smaller profile is presented in the separation between the plates, the latching action is absent, as the latching surfaces 18 a and 18 b no longer make contact. With nothing to resist backward motion, the boat may gently exit the receiver and depart from the attached trailer.
[0024] The receiver may also act to assist alignment and coupling of a boat approaching the trailer. On approach of a boat, head 1 will first contact one of guides 5 a or 5 b . As guides 5 a and 5 b are angled forward, a forward motion of the boat may be continued. Alternatively, the boat may be pushed into coupling by it's motor, or pulled forward by a tow line. Should head contact one of guides 5 a or 5 b rearward of axial members 7 a and 7 b , stops 10 a or 10 b prevent guides 5 a or 5 b from presenting face-on, which would tend to limit the guiding function. The head 1 will continue forward along the guides until it contacts both guides, as shown in FIGS. 2A and 2B. Given continued forward force or motion, the separation between guides 5 a and 5 b widens to accept head 1 , though rotation of guides 5 a and 5 b about axial members 7 a and 7 b . Tensioning component 15 , in this example a spring, lengthens in response to the pressure of head 1 against guides 5 a and 5 b . With continued forward motion, head 1 moves through the separation and beyond guides 5 a and 5 b . The guides 5 a and 5 b are then brought together into the capture position of figures 1 A and 1 B by tensioning component 15 .
[0025] In an alternative operation, guides 5 a and 5 b do not rotate but rather slide apart. In that alternative configuration, guides 5 a and 5 b may be mounted in one or more tracks, permitting lateral guide motion. As head 1 presses against a guide it is forced in an outward direction, increasing the separation between the guides. A positioning device, such as a spring, might be included to bring a guide back to a default capture position in the absence of head pressure.
[0026] Now the rotation of head 1 and related components may be controlled from the cockpit of the boat, two exemplary control systems being shown in FIGS. 4 and 5. By locating the release mechanism inside the boat, it may not be necessary to have an assistant in the course of launching the boat One person can position the boat and trailer in the water, enter the boat, operate the release, and thereby launch the boat.
[0027] Now referring to FIG. 4, a capture and release mechanism is depicted utilizing mechanical operation. A disk 30 is in physical communication with the head, and may be rotated to bring the head into a capture and a release position, for example by a shaft 2 in figure 1A. In this example, disk 30 is located within the hull, and secured though a swivel or rotating bearing device, for example a ball bearing device. A lever arm 31 is connected to disk 30 , whereby a lateral force on the end of arm 31 may rotate disk 30 . A tensional spring 33 and spring securement 32 provides force to arm 31 , whereby the arm and disk 30 may be held in a default position, which is in this example the capture position. A stop 34 may also be provided to prevent the arm from over-rotating. A cable 36 attaches to arm 31 , whereby a tensioning force on cable 36 may overcome the force exerted by spring 33 and move arm 31 into a release position shown in dashed lines, also rotating disk 30 . Cable 36 is enclosed in a sheath 38 for a portion of its run, and is secured in place by brackets 35 and 37 . A handle 39 is finally connected to cable 36 whereby an operator may pull handle 39 and put tension in cable 36 , rotating arm 31 and disk 30 into the release position.
[0028] In FIG. 5 an electrical mechanism for rotating a head is depicted. A rotating disk or swivel device 50 is provided, which is physically connected to the head as in the example of FIG. 4. A protrusion 54 is provided in disk 50 , which prevents the disk from rotating beyond a range of motion defined by stops 53 a and 53 b . A reversible DC motor 52 is provided, which is coupled to the teeth in disk 50 through a set of reduction gears, or in this example one reduction gear 51 . DPST switch 55 provides a connection from a power source, such as a battery, to the forward and reverse terminals of motor 52 , thereby causing rotation of disk 50 to a capture and a release position. If desired, further electronics may be incorporated whereby a momentary switch may be used. In that example, the default position of the toggle will be sensed by the electronics, which causes motor 52 to drive the disk into the capture position. The electronics may further include a sensor that turns off motor 52 when disk 50 reaches a certain position. Alternatively, motor 52 may be driven for a fixed period of time, after which the motor is de-energized and battery power is conserved. Likewise, when the momentary switch is activated, motor 52 is driven into the release position. A circuit breaker or other current limiting device may be included to prevent motor 52 from being overdriven and/or overheating.
[0029] Motor 52 may be substituted with other electromechanical devices, for example a stepper motor or a solenoid, and thus the particular configuration of FIG. 5 need not be adhered to. An indicator light may also be incorporated into the cockpit, so as to give the pilot an indication of the position of the head, which he may not be able to see from the cockpit. The indicator light might utilize a sensor on the disk or motor, or a current sensor sensing the current to the motor. Many other configurations are possible, as will be seen by one of ordinary skill.
[0030] Shown conceptually in FIG. 6 is a trailer including elements as described above. Trailer 61 includes a vertically projecting member 62 , on which is mounted base 8 . Base 8 might attach through an insertable portion to vertical member 62 , secured with a setscrew or bolt. Likewise, base 8 might be attached through U-bolts, or any number of other attachments. Guides 5 a and 5 b are further mounted to base 8 , as described above. Head 1 projects from the bow of boat 63 , here shown in a decoupled position from guides 5 a and 5 b . A conventional winch tiedown system 16 may be incorporated into trailer 61 , which may secure boat 63 generally to vertical member 62 through a cable connectable to U-bolt 60 .
[0031] An alternate docking system differs from that shown in FIGS. 1A, 1B, 2 A, 2 B, 3 A and 3 B in that guides 5 a and 5 b are held in a fixed position. In that system, axial members 7 a and 7 b may be replaced by structural members, plates 5 a and 5 b firming affixed thereto through welding or other attachment. As guides 5 a and 5 b do not move in that example, tensioning component 15 and other components may be omitted, as will be understood by one of ordinary skill.
[0032] That alternate docking system utilizes a head incorporating retracting catch surfaces, one exemplary head 70 being depicted in FIG. 7. Head 7 includes a body 71 , with raised portions 72 , 73 , and 74 . In this example, body 71 may be machined from a block of metal or other hard composite or plastic as described. Alternatively, body might be fashioned from stamped and pressed metal, or many other manufacturing methods. Body also attaches to a shaft 77 , as in the above described examples. A cover, not shown, may be attached over raised portions 72 , 73 , and 74 to complete the head body assembly, for example by threaded fasteners or by welding.
[0033] Raised portion 72 provides impact strength to the front of head 70 , which is the area that may strike guides 5 a and 5 b . Raised portion 73 provides protection for the internal components of head 70 , and may further prevent insertion of foreign objects. Pawls 75 a and 75 b (catches), pivot about pins 78 a and 78 b , which might in one example be pressed into body 71 and the top. Pawls 75 a and 75 b may move into an extended and retracted position, pawl 75 a being shown in the extended and pawl 75 b shown in the retracted positions. Pawls 75 a and 75 b are forced outward into the extended position by compression springs 76 a and 76 b, which rest in recesses in raised portion 74 .
[0034] The docking operation of head 70 is as follows. Head 70 first encounters guides on it's forward surfaces, which surround raised region 72 . As the head moves forward, the head encounters the separation between the guides, which in one example is about three inches. The width of body 71 is dimensioned slightly smaller than that separation. Head 70 therefore moves forward until pawls 75 a and 75 b contact the guides. Inward pressure is exerted on pawls 75 a and 75 b as the head 70 continues to move forward between the guides, by which the pawls are brought into their retracted positions. As head 70 continues forward, pawls 75 a and 75 b move beyond the guides, and snap back into extended positions. Pawls 75 a and 75 b then present latchable surfaces 79 a and 79 b to the guides, which prevents backward motion of the head out of the receiver. Head 70 may be released from the receiver by rotating to a release position, as in the above described examples.
[0035] [0035]FIGS. 8A, 8B and 8 C depict components of another head having pawls and further having a cavity 86 wherein a motor may be placed. Referring now to FIG. 8A, a left pawl 80 a is shown having a pivot hole 82 through which a pin, rivet, bolt or other securement may pivotably attach the pawl 80 a to head body 81 . A slot 83 is also provided in pawl 80 a to further secure the pawl to head body 81 and further to permit a range of rotation about the pivot hole 82 . Pivot hole 82 and slot 83 are both recessed about the perimeter, permitting a bolt or other fastener to be seated at a lower profile in the assembled head. A side rail 85 extends downward, as if looking at FIG. 8A from above, providing a surface on which a guide or plate may ride. The pawl shown in FIG. 8A might be made using stamping and/or pressing operations using plate steel material. A right pawl 80 b may be fashioned to be the mirror image of left pawl 80 a
[0036] In FIG. 8B a body 81 is shown including a cavity 86 which is shaped to accept and mount a geared motor. Cavity 86 further includes a shaft passage, not shown, for communicating the motor shaft to the exterior of body 81 to a connection with a fixed member. Recesses 88 may be provided for reducing the profile of pawls 80 a and 80 b , perhaps flush with the remainder of body 81 . Fastener holes 87 and 89 are provided to accept fasteners securing pawls 80 a and 80 b using pivot holes 82 and slots 83 . Body 81 might be fashioned using machining techniques and a machinable material such as aluminum.
[0037] Finally, in FIG. 8C an assembled head is shown using body 81 and pawls 80 a and 80 b , which pawls are mounted externally to body 81 as described above. Pawl 80 a is shown in an extended position and pawl 80 b is shown in a retracted position, as if pressure were being applied to pawl 80 b and not 80 a
[0038] Referring now to FIG. 9, another exemplary docking and securing system is depicted having a motor 102 included in head 100 . Head 100 is shown in the captured position, generally between and afore guides 101 a and 101 b . Motor 102 is of the type including internal reduction gears, and is affixed to head by way of pin 104 . A shaft 105 extends toward the bow of the boat, ending and being attached to a mounting plate 107 by a hex key 109 . As motor 102 is energized, the housing of motor 102 rotates, and head 100 also rotates being fixed thereto. Swivel plate 106 riding on bearings 110 in a bearing race are provided to resist forces that may strike the forward portion of head 100 , particularly during docking operations when head 100 may strike guides 101 a and 101 b . In this example, the rotational motion of head 100 may be restricted through stop blocks located in plates 106 and 107 , perhaps within the circumference of the bearing race. A boat adapter 108 is fashioned to fit the particular hull 111 of the boat, and attaches to mounting plate 107 , thereby securing the head assembly to the boat A motor cable 103 is passed through swivel plate 106 through a slot or large hole and through mounting plate 107 , boat adapter 108 and hull 111 through a small channel, which may then be routed to a control device in the cockpit.
[0039] The example boat attachable portion of FIG. 9 is less intrusive than earlier examples on a boat's hull, as only small holes need by made therein for fasteners and the wire channel. Additionally, the space within hull 111 is not invaded, which makes that exemplary system more suitable for boats with limited bow space.
[0040] Another exemplary boat attachable portion is depicted in figure 10A, which includes a retractable head. In this example, a head 120 a is shown captured between guides 122 a and 122 b . In this example, guides 122 a and 122 b are thicker than in prior examples, which permit pawls 121 a and 121 b to rest against the edge of those guides. As in prior examples, pawls 121 a and 121 b pivot to permit insertion of the head 120 through the separation between guides 122 a and 122 b . A spring 123 provides tension to keep pawls 121 a and 121 b in a default extended position in the absence of pressure. Now it is to be understood that pawls 121 a and 121 b might be substituted with fixed head features having other contact surfaces, provided that guides 122 a and 122 b may be separated, as in earlier examples.
[0041] Head 120 includes a shaft 124 which passes through hull 135 , in this example, and is affixed to a motor shaft 128 . Shaft 124 is restricted laterally by a guide 125 , which is affixed to an internal structure of the boat. A bearing component 126 fixes lateral motion at the end of shaft 124 while permitting rotation thereof. Motor shaft 128 is driven by motor 127 through internal reduction gears to provide the necessary torque to rotate head 120 in operation. A carriage 134 provides a platform for motor 127 and other components, and is permitted to travel through a range in a forward and rearward motion relative to the hull 135 . In this example, carriage 134 is affixed to slides 129 a and 129 b , which are in turn attached to a bracket 130 affixed to an internal structure of the boat. The position of carriage 134 is controlled by driving motor 131 , on which is attached a gear 133 affixed to that motor's shaft. As gear 133 rotates, a force is exerted on carriage 134 through toothed track 132 , which teeth mesh and communicate with the teeth of gear 133 .
[0042] As gear 133 rotates in a forward-driving rotation, track 132 and carriage 134 are forced forward, which also forces shaft 124 and head 120 into a more extended position from the hull 135 . Likewise, a rearward-driving rotation on gear 133 retracts shaft 124 and head 120 toward the hull. Guide 125 may be configured to act as a forward stop for carriage 134 , perhaps using a surface of bearing component 126 . Other devices may be included to stop motion in the forward or rearward directions of carriage 134 , as will be understood by one of ordinary skill. Likewise, rotational stops may be included to restrict the rotation of shaft 124 , which might, for example, be accomplished by the insertion of one or more pins into the shaft coming into interference with other components fixed to the boat. In an alternate configuration, a solenoid replaces motor 131 , and gear 133 and track 132 are omitted.
[0043] Referring now to FIG. 10B, a bow-mounted portion is depicted similar to that of FIG. 10A further including a head 120 b retractable into a recess 136 . In that example, head 120 b is shaped to match the curve of hull 135 , although that is not a requirement Head 120 b may be painted or finished similarly to the hull 135 , which may serve to camouflage or reduce the noticeability of the head.
[0044] As for materials, many types of materials may be used, provided that consideration is given to the desirable strength and durability of the system. Aluminum may be particularly desirable, as it is not subject to rust and is relatively easy to machine. Stainless steel is also a good choice, with its relative strength. Steel might also be advantageously used, especially if plated with nickel or other rust-inhibiting material. Yet many other metals, plastics and composites might be used, as will be understood by one of ordinary skill.
[0045] In another exemplary system the bow portion is constructed of rust-impervious materials, such as aluminum and nylon, as the bow portion is the most likely to encounter long exposure to water. In that system, the receiver portion may be fashioned from steel, rubber and other weathering materials, provided that moving portions are lubricated sufficiently to ensure protection and movement of joints. The receiver portion may also be coated, for example with enamel, to prolong the life of the component parts.
[0046] Now although the systems described above have been discussed in relation to a boat, those systems may be adapted to other watercraft types with minor modification, for example hovercrafts and jet-skis, and many other types. Described systems might also be adapted for use with land vehicles, for example all-terrain vehicles. The scope of use of the above described systems should therefore be interpreted broadly rather than restrictively.
[0047] While various systems incorporating a bow mountable portion capturable in a receiver or trailer portion have been described and illustrated in conjunction with a number of specific configurations and methods, those skilled in the art will appreciate that variations and modifications may be made without departing from the principles herein illustrated, described, and claimed. The present invention, as defined by the appended claims, may be embodied in other specific forms without departing from its spirit or essential characteristics. The configurations described herein are to be considered in all respects as only illustrative, and not restrictive. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope. | Disclosed herein are various exemplary watercraft docking systems including a boat attachable portion that couples and aligns to a trailer portion. Detailed information on various example embodiments of the inventions are provided in the Detailed Description below, and the inventions are defined by the appended claims. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Application Ser. No. 60/862,906 filed on Oct. 25, 2006, entitled “DISPENSING METHOD FOR VARIABLE LINE VOLUME”, the entire contents of which are incorporated herein by reference.
BACKGROUND
[0002] 1. Field of the Invention
[0003] This invention relates to an apparatus and method of printing a conductive heater grid on plastic or glass glazing panels. More particularly, it relates to the printing conductive heater grids on glazing panels used as backlights in motor vehicles.
[0004] 2. Description of Related Art
[0005] Plastic materials, such as polycarbonate (PC) and polymethylmethyacrylate (PMMA), are currently being used in the manufacturing of numerous automotive parts and components, such as B-pillars, headlamps, and sunroofs. Automotive rear window (backlight) systems represent one application for these materials due to their many identified advantages, particularly in the areas of styling/design, weight savings, and safety/security. More specifically, plastic materials offer the automotive manufacturer the ability to reduce the complexity of the rear window assembly through the integration of functional components into the molded plastic system, as well as the ability to distinguish their vehicles by increasing overall design and shape complexity. Being lighter in weight than conventional glass backlight systems, their incorporation into the vehicle may facilitate both a lower center of gravity for the vehicle (and therefore better vehicle handling & safety) and improved fuel economy. Further, enhanced safety is realized, particularly in a roll-over accident because of a greater probability of the occupant or passenger being retained in the vehicle.
[0006] Although there are many advantages associated with implementing plastic windows, these windows are not without technical hurdles that must be addressed prior to wide-scale commercialization. Limitations relating to material properties include the stability of plastics during prolonged exposure to elevated temperatures and the limited ability of plastics to conduct heat. Regarding the latter, in order to be used as a backlight in a vehicle, the plastic material must be compatible with the use of a defroster or defogging system (hereafter just referred to as a “defroster”). For commercial acceptance, a plastic backlight must meet the performance criteria established for the defrosting or defogging of glass backlights.
[0007] The difference in material properties between glass and plastics becomes quite apparent when considering heat conduction. The thermal conductivity of glass (T c =22.39×10 −4 cal/cm-sec-° C.) is approximately 4 to 5 times greater than that exhibited by a typical plastic (e.g., T c for polycarbonate=4.78×10 −4 cal/cm-sec-° C.). Thus; a defroster designed to work effectively on a glass window may not necessarily be efficient at defrosting or defogging (hereafter just “defrosting” or “defrost”) a plastic Window. The lower thermal conductivity of the plastic may limit the dissipation of heat from the heater grid lines across the surface of the plastic window. Thus, at a similar power output, a heater grid on a glass window may defrost the entire viewing area, while the same heater grid on a plastic window may only defrost those portions of the viewing area that are close to the grid lines.
[0008] A second difference between glass and plastics that must be overcome is related to the electrical conductivity exhibited by a printed heater grid. The thermal stability of glass, as demonstrated by a relatively high softening temperature (e.g., T soften >>1000° C.), allows for the sintering of a metallic paste on the surface of the glass window to yield a substantially inorganic frit or metallic wire. Since the softening temperature of glass is significantly greater than the glass transition temperature of a typical plastic resin (e.g., polycarbonate T g =145° C.), a metallic paste cannot be sintered onto a plastic panel. Rather, it must be cured on the panel at a temperature lower than the T g of the plastic resin.
[0009] A metallic paste typically consists of metallic particles dispersed in a polymeric resin that will bond to the surface of the plastic to which it is applied. The curing of the metallic paste provides a conductive polymer matrix having closely spaced metallic particles dispersed throughout a dielectric layer. The presence of the dielectric layer (e.g., polymer) between dispersed conductive particles leads to a reduction in the conductivity, or an increase in resistance, of the cured heater grid lines, as compared to dimensionally similar heater grid lines sintered onto a glass substrate. This difference in conductivity manifests itself in poor defrosting characteristics exhibited by the plastic window, as compared to the glass window.
[0010] With the above in mind, it is clear that controlling the quality of the heater grid printed onto the panel is important in maximizing the efficiency and effectiveness of any defroster used with that panel. Various parameters affect the quality of the printed heater grid including variances in the width, height (i.e. volume) and straightness of the grid lines. The more variances that exist in width and height, the greater the negative impact on the effectiveness of the defroster. This is a result of unequal resistances in various sections of the grid line and busbars resulting in unequal resistive heating in various sections of the defroster. With regard to straightness, this is mainly an aesthetic concern that becomes more of an issue because of the ability of plastic window assemblies to have greater design flexibility and curvature.
[0011] A defroster may be printed directly onto the inner or outer surface of a panel, or on the surface of a protective layer, using a conductive ink or paste and various methods known to those skilled in the art. Such methods include, but are not limited to, screen-printing, ink jet printing and automatic dispensing. Automatic dispensing includes techniques known to those skilled in the art of adhesive application, such as drip & drag, streaming, and simple flow dispensing. Slower speeds and higher flow for the ink or paste rates can result in wider and higher grid lines although with the possibility of reduced line quality. Conversely, higher speeds and slower flow rates can result in slimmer and lower grid lines. With screen printing in particular, the height of the grid line is not readily variable.
[0012] From the above, it is seen that there is a need for an apparatus and method that can effectively control the quality and consistency with which grid lines are printed onto a panel.
SUMMARY OF THE INVENTION
[0013] In overcoming the enumerated drawbacks and other limitations of the related art, the present invention provides an apparatus for printing grid lines formed from a conductive ink onto a plastic substrate or panel. The apparatus includes a support bed adapted to support the panel and an articulatable arm positioned relative the support bed such that an end of the arm opposes a surface of the panel to be printed. A dispensing nozzle is carried by the arm and mounted at the end of the arm; the nozzle is coupled to a source of conductive ink and to a nozzle height actuator that mounts the nozzle to the arm. Finally, a flow regulator is coupled to the ink source and the nozzle whereby the flow rate of conductive ink out of the nozzle is regulated. The apparatus also includes a height sensor configured to output a height signal relative to the surface of the panel. A controller, coupled to the arm, the flow regulator, the nozzle height actuator and the height sensor, is configured to articulate the arm so as to move the nozzle in a predetermined pattern about the surface of the panel and dispense grid lines having a predetermined volume. The controller is also configured to retrace at least part of the pattern and vary the volume on the grid lines
[0014] The present invention also includes a method for printing a conductive trace on the plastic panel. The method includes locating a nozzle proximate to a surface of the panel; moving the nozzle relative to the surface; dispensing a conductive ink onto the surface to form a grid; and retracing at least a portion of the grid to vary a volume of grid lines forming the grid.
[0015] Further objects, features and advantages of this invention will become readily apparent to persons skilled in the art after a review of the following description, with reference to the drawings and claims that are appended to and form a part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIGS. 1A, 1B , 1 C and 1 D are schematic sectional views of four alternative embodiments of a window assembly as might be formed utilizing the present invention;
[0017] FIG. 2 is a perspective view of an apparatus according to the present invention and including a robot arm traversing a dispensing head over a panel of a window assembly;
[0018] FIG. 3 is a partial front view of the robot arm and dispensing head over the panel; and
[0019] FIG. 4 is a close up, cross sectional view of a heater grid line disposed on the panel utilizing the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Referring now to FIG. 1 , a cross-section of various examples of a plastic assembly 20 having a defroster or heater grid 16 is shown. The heater grid 16 may be positioned toward the external surface 18 of a plastic window assembly 20 (Example A), on an internal surface 22 of the plastic window assembly 20 (Example B and C), or encapsulated within the plastic panel (Example D) itself of the plastic window assembly 20 . Each of the possible positions of the heater grid 16 in the example offers different benefits in relation to overall performance and cost of the window assembly 20 . Positioning the heater grid 16 toward the external surface 18 (Example A) of the window assembly 20 is preferred so as to minimize the time necessary to defrost the window assembly 20 . Positioning the heater grid 16 on the internal surface 22 (Example B and C) of a plastic panel 24 of the window assembly 20 offers benefits in terms of ease of application and lower manufacturing costs.
[0021] The transparent plastic substrate or panel 24 itself may be constructed of any thermoplastic polymeric resin or a mixture or combination thereof. Appropriate thermoplastic resins include, but are not limited to, polycarbonate resins, acrylic resins, polyarylate resins, polyester resins, and polysulfone resins, as well as copolymers and mixtures thereof. The panels 24 may be formed into a window through the use of any of the various known techniques, such as molding, thermoforming, or extrusion. The panels 24 may further include areas of opacity 26 applied by printing an opaque ink on the panel 24 in the form of a black-out border by molding a border using an opaque resin.
[0022] The heater grid 16 may be printed directly onto the inner surface 28 or outer surface 30 of the plastic panel 24 . Alternatively, it may be printed on the surface of one or more protective layers 32 , 34 . In either construction, printing is affected using a conductive ink. The conductive ink may be modified with pigments, dyes, and/or fillers for aesthetic (color) and/or functional reasons (electrical conductivity). Common pigments may include: white pigments (e.g., titanium dioxide); yellow pigments, such as iron oxide yellow, chrome yellow, titanium yellow, diarylide yellow, monoarylide (monoazo) yellow, nickel azo yellow, vat yellow, and benzimidazolone yellow; red pigments, such as Iron oxide, toluidine red, naphthol red, quinacridone; blue and green pigments, such as iron blue, ferric ammonium ferrocyanide, copper phthalocyanine, phthalo blue, phthalo green; or black pigments, such as carbon black and acetylene black. Common dyes may include azo metal complexes in various colors. Common fillers may include: calcium carbonate, aluminum silicate (clay), magnesium silicate, silicon dioxide, and barium sulfate. A material with a positive temperature coefficient (PTC) may also be used as a filler. This filler would serve as a temperature regulating mechanism for the dispensed lines.
[0023] In its final construction, the plastic panel 24 may be protected from such natural occurrences as exposure to ultraviolet radiation, oxidation, and abrasion through the use of a single protective layer 32 on the exterior side of the panel 24 or additional, optional protective layers 34 on the interior side of the panel 24 . As the term is used herein, a transparent plastic panel 24 with at least one protective layer 32 is defined as a “glazing”.
[0024] The protective layers 32 , 34 may be a plastic film, an organic coating, an inorganic coating, or a mixture thereof. The plastic film may be of the same or different composition as the transparent panel. The film and coatings may comprise ultraviolet absorber (UVA) molecules, rheology control additives, such as dispersants, surfactants, and transparent fillers (e.g., silica, aluminum oxide, etc.) to enhance abrasion resistance, as well as other additives to modify optical, chemical, or physical properties. Examples of organic coatings include, but are not limited to, urethanes, epoxides, and acrylates and mixtures or blends thereof. Some examples of inorganic coatings include silicones, aluminum oxide, barium fluoride, boron nitride, hafnium oxide, lanthanum fluoride, magnesium fluoride, magnesium oxide, scandium oxide, silicon monoxide, silicon dioxide, silicon nitride, silicon oxy-nitride, silicon oxy-carbide, silicon carbide, tantalum oxide, titanium oxide, tin oxide, indium tin oxide, yttrium oxide, zinc oxide, zinc selenide, zinc sulfide, zirconium oxide, zirconium titanate, or glass, and mixtures or blends thereof.
[0025] The protective coatings applied as protective layers 32 , 34 may be applied by any suitable technique known to those skilled in the art. These techniques include deposition from reactive species, such as those employed in vacuum-assisted deposition processes, and atmospheric coating processes, such as those used to apply sol-gel coatings to substrates. Examples of vacuum-assisted deposition processes include but are not limited to plasma enhanced chemical vapor deposition, ion assisted plasma deposition, magnetron sputtering, electron beam evaporation, and ion beam sputtering. Examples of atmospheric coating processes include but are not limited to curtain coating, spray coating, spin coating, dip coating, and flow coating.
[0026] As an illustrative example, a polycarbonate panel 24 comprising the Exatec® 900 automotive window glazing system (Exatec®, LLC, Wixom, Mich.) with a printed defroster 16 generally corresponds to the embodiment of FIG. 1C . In this particular case, the transparent polycarbonate panel 24 is protected with a multilayer coating system (Exatec® SHP-9× or Exatec® SHX, (Exatec, LLC, Wixom, Mich.) and a deposited layer of a “glass-like” coating (SiO x C y H z ) that is then printed with a heater grid 16 on the exposed surface of the protective layer 34 intended to face the interior of the vehicle. As a further alternative construction, a heater grid 16 may be placed on top of a layer or layers of a protective coating or coatings 32 , 34 , and then over-coated with an additional layer or layers of a protective coating or coatings. For instance, a heater grid 16 may be placed on top of a silicone protective coating (e.g., AS4000 by GE Silicones) and subsequently over-coated with a “glass-like” film.
[0027] Turning now to the present invention, FIG. 2 illustrates one example of an apparatus 40 , which may be a robotic arm or other device, for dispensing conductive ink upon the panel 24 (or glazing), resting on a support 38 , to form a series of heater grid lines 54 . The machine 40 includes a robot arm 42 , mounted in a stationary manner to a support surface, and a dispensing head 44 attached to the end of the robot arm 42 . A controller 45 is electrically coupled to the robot arm 42 , the dispensing head 44 and a flow regulator 47 that is fluidly coupled to a conductive ink source 49 . The robot arm 42 is articulatable and capable of moving the dispensing head 44 to any point on the surface 22 of the panel 24 . Other examples of the machine 40 for dispensing a conductive material include those provided in U.S. patent application Ser. No. 11/321,567 filed on Dec. 29, 2005, which is herein incorporated by reference. The term dispensing utilized throughout the description of the invention presented here encompasses the various embodiments of the deposition method and apparatus described herein and in the aforementioned patent application. Alternatively, the dispensing head 44 may remain stationary while the support 38 is articulated to move relative to the dispensing head 44 .
[0028] In a preferred operation, the robot arm 42 moves the dispensing head 44 in a linear direction across the panel 25 and the dispensing head dispenses the conductive ink from the source 49 onto the panel 25 in lines, forming the heater grid lines 54 , only some of which are shown in FIG. 2 for clarity. While this is an exemplary embodiment, other examples may dispense the heater grid lines 54 in any other pattern, such as curves.
[0029] Looking more closely at the dispensing head 44 , it is primarily composed of a base 46 supported by the robot arm 42 . Coupled to the base 46 is a sensor 50 and an actuator 52 , to which a nozzle 48 is mounted and further coupled to the conductive ink source 49 and flow regulator 47 . The flow regulator 47 may be any device capable of controlling the flow rate of ink from the ink source 49 to the nozzle 48 . During operation, by means of the flow regulator, the conductive ink is dispensed through the nozzle 48 , onto the internal surface 22 of the panel 24 . The flow regulator 47 may include, but not be limited to, a means of positively displacing the fluid, such as that known to occur via an auger, a piston, or a gear mechanism. To minimize weeping/drooling and excessive material buildup at printing starts and stops, the flow of material may be reversed by the flow regulator to “suckback” and prevent dispensing of excessive material. This may be accomplished in a variety of ways including reversing the rotation of the auger in a screw-type delivery system or applying vacuum to a pressure type delivery system.
[0030] To ensure the ink is dispensed in a manner to form the grid lines 54 of the desired width and height, the sensor 50 , directly or indirectly, measures the distance of the dispensing head 48 from the surface 22 of the panel 24 . As a result, the controller 45 , while controlling the robot arm 42 to move the dispensing head 44 to a desired position over the surface 22 , actively controls a z-axis position (height relative to the panel 24 ) of the nozzle 48 using the actuator 52 based on input from the sensor 50 . The actuator 52 translates the position of the nozzle 48 to within a precise height 56 along the z-axis, (see FIG. 2 ), typically 0-3 mm or less, but more preferably between 0.51 mm, from the surface 22 , depending on the desired characteristics of the grid lines 54 . While the actuator 52 is a linear motor, alternative embodiments may use any electric, hydraulic, pneumatic, piezoelectric, electromagnetic, or other actuator 52 capable of similar precision and response time. Alternatively, the actuator 52 may be attached to the support 38 (not shown) to articulate the support 38 in the z-axis relative to the nozzle 48 .
[0031] The sensor 50 is any sensor capable of measuring a height 56 from the surface 22 of the panel 24 and must be capable of measuring relative to a semi-reflective and/or transparent surface. While the exemplary sensor 50 is a laser triangulation sensor, any other non-contact sensor 50 could also be used, for example, a photonic sensor (i.e. measures the intensity of the reflected light), an air pressure sensor, an ultrasonic sensor, a magnetic sensor, or any other sensor. Additionally, contact sensors with appropriate means contacting the surface 22 in an appropriate manner (i.e. rolling contacts, sliding contacts, etc.) are also anticipated as being applicable with the present invention.
[0032] In the example shown, the sensor 50 comprises a triangulation laser arrangement made up of an emitter 58 and a receiver 60 . To measure the distance of the nozzle 48 from the internal surface 22 , laser light is projected from the emitter 58 and either directed or reflected onto the surface 22 . The light is then reflected back to the receiver 60 and, based on the relative positions of the emitter 58 to the receiver 60 , the sensor 50 calculates, by triangulation, the distance of the surface 22 from a reference point of the sensor 50 . The height 56 is then calculated by the controller 45 based on the signal from the sensor 50 and a known position of the actuator 52 and the nozzle 48 . As a result, the controller 45 may command the actuator 52 to raise or lower the nozzle 48 along the z-axis to compensate for variations in the surface of the panel 24 and maintain a predetermined height 56 above the surface 22 . To increase the signal to noise ratio of this and other light based displacement sensors for height measurement, the surface of the fixture used to hold the partially transparent substrate panel may be coated with an anti-reflective coating such as flat black paint. Other anti-reflective methods may include surface texturing and/or baffling.
[0033] While the present embodiment compensates for variations in the z-axis, alternate embodiments may also compensate for variations in the x-axis and y-axis in order to keep the nozzle 48 normal to the surface 22 as it traverses the panel 24 . Such an embodiment may be achieved using a plurality of sensor's 50 and actuator's 52 to manipulate the nozzle accordingly. In one embodiment, at least two additional sensor's 50 would measure the positions (x & y-axes) of the surface 22 to determine curvature in the panel. Based on inputs from these sensors, the controller 45 would command the robot arm 42 and/or additional actuator's to precisely rotate the nozzle 48 about the x-axis and y-axis, in addition to translating along the z-axis. As a result, the controller 45 may keep the nozzle 48 normal to the surface 22 at all times as it translates across the panel 24 .
[0034] To reduce application errors due to part-to-part variability in the manufacturing process, the support 38 may be a precision substrate fixture with sufficient clamping strength and rigidity to deform the substrate into a predetermined shape. For example, a vacuum may be applied through a plurality of holes (not shown) in the support 38 to clamp the panel 24 to the support 38 .
[0035] Those portions of the apparatus that come into contact with the conductive ink may be heated to a predetermined temperature to minimize the effect of temperature induced changes in the rheology of the ink. Preferably, this temperature would be high enough to encompass any fluctuations in room temperature yet not high enough to effect the ink in a negative way (i.e. degradation). For example, the panel 24 , the nozzle 48 , the flow regulator 47 and the source of conductive ink 49 may all be heated.
[0036] In order to achieve continuous, smooth motion along complex paths comprised of linear motion statements, approximate positioning of the dispensing apparatus and/or substrate is necessary. By specifying the percentage of the programmed velocity at which the approximate positioning begins, one can cause the articulation apparatus to move smoothly without the need to stop at each individual programmed location. This enhances the visual appearance of the dispensed feature while decreasing overall cycle time.
[0037] As a result, this arrangement allows for the precise control of the characteristics of the heater grid lines 54 by varying (increasing or decreasing) the height (h) 56 of the dispensing head 44 relative to the panel 24 and the flow rate (r) at which the ink is dispensed, based on the speed at which the dispensing head is being moved across the panel 24 . Therefore, by precisely adjusting the height 56 of the nozzle 48 relative to the contour of the panel 24 , and/or adjusting the flow rate of conductive ink from the nozzle 48 , the apparatus 40 is able to dispense the ink in straight lines of having a width 64 and a height 66 , resulting in a consistent volume unit (see FIG. 4 ) for the grid line 54 . The height 66 and width 64 , and hence the volume of the grid lines 54 , can be varied to control the resistivity over the length or in a section of the grid lines 56 . This is necessary in many applications to achieve a proper current density for thermal performance. It may be desirable to increase the volume of a grid line 54 to reduce the current density and alleviate a “hot spot” in a particular portion of the grid. In current automotive defroster designs, the grid lines may have a larger width near a busbar adjacent either end of the defroster and a taper to a smaller width in the center of the grid between busbars. With the present invention, a larger volume can be built near the busbars with a smaller volume near the center of the grid lines between the busbars
[0038] The volume can be varied by changing the width, the height and/or amount of conductive ink dispensed to make the grid lines. Changing the width and/or height of the traces requires dispensing the ink at a greater height, which may result in decreased line quality (i.e. waviness or meandering). Changing the volume by increasing or decreasing the amount of conductive ink dispensed is also problematic since adjusting the rate of ink delivery is difficult with current systems, often requiring hardware changes in the middle of dispensing the grid that require downtime and increase production costs.
[0039] However, the volume, via the width 64 ′ and height 66 ′, can also be changed by dispensing one initial set of gridlines having a minimum volume. This minimum volume may correspond to, for instance, the volume in the center of the automotive defroster grid. Thicker gridlines may be provided by retracing the initial grid lines and dispensing more material adjacent to and/or over the initial grid lines in areas where such material (additional volumes) is required (i.e. near the busbar of the automotive defroster grid). Where it is desired to maintain the initial volume of the grid lines, no additional material is dispensed in those areas during the retracing process. This permits variable line volumes with desirable aesthetic characteristics and without having to make hardware changes to the machine.
[0040] As a person skilled in the art will readily appreciate, the above description is meant as an illustration of implementation of the principles this invention. This description is not intended to limit the scope or application of this invention in that the invention is susceptible to modification, variation and change, without departing from spirit of this invention, as defined in the following claims. | An apparatus and method for printing a conductive grid onto a plastic panel, and a resultant product. A nozzle is mounted to the end of an arm, and the nozzle is coupled to a source of conductive ink. A flow regulator, coupled to the ink source, regulates the flow rate of ink out of the nozzle and is controlled by a controller. The controller is further configured to apply an initial conductive trace onto a panel and to apply a subsequent conductive trace beside or onto the initial conductive trace to vary the volume of the grid line along a portion of its length. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the priority of Korean Patent Application No. 2008-0048156 filed on May 23, 2008, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to film type antennas and mobile communication terminals, and more particularly, to a film type antenna that has a contact structure to stably connect the film type antenna, formed integrally with a case of a mobile communication terminal, with a board inside the mobile communication terminal, and a mobile communication terminal using the film type antenna.
[0004] 2. Description of the Related Art
[0005] Recently, mobile wireless terminals that separately use various kinds of bandwidths, such as CDMA, PDA, DCS, and GSM, or use all of the bandwidths, have come into widespread use. Terminals that have various kinds of functions and designs have appeared. As the terminals have gradually been reduced in size, thickness, and weight, the diversity of the functions of the terminals has attracted attention. Therefore, emphasis is placed on reducing the volume of the terminals while the terminals maintain the function of an antenna.
[0006] Particularly, in a case of an antenna, for example, a rod antenna or a helical antenna that protrudes from the outside of a terminal by a predetermined length has excellent characteristics because of omnidirectional radiation. However, the rod antenna or the helical antenna of the terminal is most susceptible to damage when it falls down, and reduces portability. Therefore, research has been conducted on an in-molding antenna that is formed integrally with a case of a mobile communication terminal.
SUMMARY OF THE INVENTION
[0007] An aspect of the present invention provides a film type antenna that has a contact structure to stably connect the film type antenna, formed integrally with a case of a mobile communication terminal, with a circuit of a board inside the mobile communication terminal, and a mobile communication terminal having the film type antenna.
[0008] According to an aspect of the present invention, there is provided a film type antenna including: a carrier film; a conductive pattern provided on one surface of the carrier film; and a conductive buffer layer provided on one surface of the conductive pattern.
[0009] The conductive buffer layer may be provided at a contact area where the conductive pattern is connected to an external circuit.
[0010] The conductive buffer layer may be a conductive rubber.
[0011] The film type antenna may further include an adhesive layer provided between the conductive pattern and the conductive buffer layer.
[0012] The adhesive layer may be copper foil tape.
[0013] According to another aspect of the present invention, there is provided a mobile communication terminal including: a carrier film; a conductive pattern provided on one surface of the carrier film; a conductive buffer layer provided on one surface of the conductive pattern; and a housing provided integrally with the carrier film.
[0014] The conductive buffer layer may be provided at a contact area where the conductive pattern is connected to an external circuit.
[0015] The conductive buffer layer may be conductive rubber.
[0016] The mobile communication terminal may further include an adhesive layer provided between the conductive pattern and the conductive buffer layer.
[0017] The adhesive layer may be copper foil tape.
[0018] The conductive pattern may be provided between the carrier film and the housing.
[0019] The carrier film may be provided on an outer surface of the housing.
[0020] The conductive buffer layer may be provided between the conductive pattern and the housing.
[0021] The mobile communication terminal may further include a connector in contact with the conductive buffer layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The above and other aspects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
[0023] FIG. 1 is a cross-sectional view illustrating a film type antenna according to an exemplary embodiment of the invention;
[0024] FIG. 2 is a cross-sectional view illustrating a film type antenna according to another exemplary embodiment of the invention;
[0025] FIG. 3 is a cross-sectional view illustrating a mobile communication terminal according to still another exemplary embodiment of the invention; and
[0026] FIG. 4 is a cross-sectional view illustrating a mobile communication terminal according to yet another exemplary embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0027] Exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
[0028] FIG. 1 is a cross-sectional view illustrating a film type antenna according to an exemplary embodiment of the invention.
[0029] Referring to FIG. 1 , a film type antenna 100 according to an exemplary embodiment of the invention may include a carrier film 110 , a conductive pattern 120 , and a conductive buffer layer 130 .
[0030] The carrier film 110 may be formed of a material that is appropriate to perform in-molding labeling (IML). Specifically, the carrier film 110 that has the conductive pattern 120 formed on one surface thereof is inserted into a mold for manufacturing a housing of a mobile communication terminal, synthetic resins used to form the housing of the mobile communication terminal are injected into the mold, and the housing are molded from the synthetic resins at the appropriate temperature and pressure. Therefore, the material that forms the carrier film 110 needs to be material that does not undergo significant deformation under the pressure and temperature during the in-molding labeling, and at the same time, can be formed integrally with the housing of the mobile communication terminal. In this embodiment, the carrier film 110 may include a thin, insulating polymer material.
[0031] The conductive pattern 120 may be an antenna pattern that is formed on one surface of the carrier film 110 .
[0032] The conductive pattern 120 may be formed by using various kinds of methods. First, a conductive pattern may be printed onto the conductive ink carrier film 110 by using conductive ink. Alternatively, a desired pattern may be directly formed on the carrier film by sputtering or evaporation. The conductive pattern 120 may be a conductive pattern that is formed of previously manufactured metal foil which is then attached to the carrier film 110 .
[0033] The conductive pattern 120 includes a power feed terminal, and may also include a connection terminal for providing an electrical connection to an external circuit, such as a ground terminal. In this embodiment, the power feed terminal may be a contact area where the conductive pattern is connected to an external power feed line.
[0034] The conductive buffer layer 130 may be formed at the contact area where the conductive pattern 120 can be connected to the external circuit. That is, the conductive buffer layer 130 may be formed over the area of the conductive pattern where the power feed terminal is formed.
[0035] In order to connect the conductive pattern 120 to a board, a connector may be used. The conductive buffer layer 130 is formed over an area where the connector is in contact with the conductive pattern. The conductive buffer layer 130 may serve as a buffer between the connector and the conductive pattern. The use of the conductive buffer layer 130 can improve contact stability between the connector and the conductive pattern.
[0036] The conductive buffer layer 130 may have conductivity since the conductive buffer layer 130 electrically connects the connector and the conductive pattern to each other. The conductive buffer layer 130 may be formed of a material having predetermined elasticity so as to improve the contact stability between the connector and the conductive pattern.
[0037] In this embodiment, the conductive buffer layer 130 may be conductive rubber. The conductive rubber features both conductivity and elasticity, making it suitable for use as the conductive buffer layer 130 .
[0038] FIG. 2 is a cross-sectional view illustrating a film type antenna according to another exemplary embodiment of the invention.
[0039] Referring to FIG. 2 , a film type antenna 200 according to this embodiment may include a carrier film 210 , a conductive pattern 220 , a conductive buffer layer 230 , and an adhesive layer 240 .
[0040] The carrier film 210 may be formed of a material that is appropriate to perform in-molding labeling (IML). Specifically, the carrier film 210 that has the conductive pattern 220 formed on one surface thereof is inserted into a mold for manufacturing a housing of a mobile communication terminal, synthetic resins used to form the housing of a mobile communication terminal are injected into the mold, and the housing is molded from the synthetic resins at the appropriate temperature and pressure. Therefore, the material that forms the carrier film 210 needs to be material that does not undergo significant deformation under the pressure and temperature during the in-molding labeling, and at the same time, can be formed integrally with the housing of the mobile communication terminal. In this embodiment, the carrier film 210 may include a thin, insulating polymer material.
[0041] The conductive pattern 220 may be an antenna pattern that is formed on the one surface of the carrier film 210 .
[0042] The conductive pattern 220 may be formed by using various kinds of methods. A conductive pattern may be printed onto the carrier film 210 by using conductive ink. Alternatively, a desired pattern may be directly formed on the carrier film by sputtering or evaporation. The conductive pattern 220 may be a conductive pattern that is formed of previously manufactured metal foil which is then attached to the carrier film 210 .
[0043] The conductive pattern 220 includes a power feed terminal, and may also include a connection terminal for providing an electrical connection to an external circuit, such as a ground terminal. In this embodiment, the power feed terminal may be a contact area where the conductive pattern is connected to an external power feed line.
[0044] The conductive buffer layer 230 may be formed over the contact area where the conductive pattern 220 can be connected to the external circuit. That is, the conductive buffer layer 230 may be formed at an area where the power feed terminal of the conductive pattern is formed.
[0045] A connector may be used to connect the conductive pattern 220 to a board. The conductive buffer layer 230 may be formed over the area where the connector is in contact with the conductive pattern. The conductive buffer layer 230 may serve as a buffer between the connector and the conductive pattern. The use of the conductive buffer layer 230 can improve contact stability between the connector and the conductive pattern.
[0046] The conductive buffer layer 230 may have conductivity since the conductive layer 230 electrically connects the connector and the conductive pattern to each other. Further, the conductive buffer layer 230 may have predetermined elasticity so as to improve the contact stability between the connector and the conductive pattern.
[0047] In this embodiment, the conductive buffer layer 230 may be conductive rubber. The conductive rubber features both conductivity and elasticity, making it suitable for use as the conductive buffer layer.
[0048] The adhesive layer 240 may be formed between the conductive pattern 220 and the conductive buffer layer 230 . The adhesive layer 240 increases adhesive strength between the conductive pattern 220 and the conductive buffer layer 230 , thereby preventing separation of the conductive buffer layer 230 from the conductive pattern 220 during the in-molding labeling.
[0049] In this embodiment, metal foil tape may be used as the adhesive layer 240 .
[0050] When the metal foil tape is used, copper foil tape 240 may be applied to the conductive pattern 220 , and the conductive rubber 230 may be applied to the copper foil tape. The copper foil tape has conductivity, and can strengthen the function of the conductive buffer layer 230 .
[0051] FIG. 3 is a cross-sectional view illustrating a mobile communication terminal according to still another exemplary embodiment of the invention.
[0052] Referring to FIG. 3 , a mobile communication terminal 300 according to this embodiment may include a carrier film 310 , a conductive pattern 320 , a conductive buffer layer 330 , and a housing 350 of the mobile communication terminal.
[0053] The carrier film 310 may be formed of a material that is appropriate to perform in-molding labeling (IML). Specifically, the carrier film 310 that has the conductive pattern 320 formed on one surface thereof is inserted into a mold for manufacturing the housing of the mobile communication terminal, synthetic resins used to form the housing of the mobile communication terminal are injected into the mold, and the housing is molded from the synthetic resins at the appropriate temperature and pressure. Therefore, the material that forms the carrier film 310 needs to be a material that does not undergo significant deformation under the pressure and temperature during the in-molding labeling, and at the same time, can be formed integrally with the housing of the mobile communication terminal. In this embodiment, the carrier film 310 may include a thin insulating polymer material.
[0054] The conductive pattern 320 may be an antenna pattern that is formed on one surface of the carrier film 310 .
[0055] The conductive pattern 320 may be formed by using various kinds of methods. A conductive pattern may be printed onto the carrier film 310 by using conductive ink. Alternatively, a desired pattern may be directly formed on the carrier film by sputtering or evaporation. The conductive pattern 320 may be a conductive pattern that is formed of previously manufactured metal foil which is then attached to the carrier film 310 .
[0056] The conductive pattern 320 includes a power feed terminal, and may also include a connection terminal for providing an electrical connection to an external circuit, such as a ground terminal. In this embodiment, the power feed terminal may be a contact area where the conductive pattern is connected to an external power feed line.
[0057] The conductive buffer layer 330 may be formed over the contact area where the conductive pattern 320 can be connected to the external circuit. That is, the conductive buffer layer 330 may be formed over the area where the power feed terminal of the conductive pattern is formed.
[0058] A connector may be used to connect the conductive pattern 320 to a board. The conductive buffer layer 330 is formed over the area where the connector is in contact with the conductive pattern. The conductive buffer layer 330 may serve as a buffer between the connector and the conductive pattern. The use of the buffer layer 330 can improve contact stability between the connector and the conductive pattern.
[0059] The conductive buffer layer 330 may have conductivity since the conductive buffer layer 330 electrically connects the connector and the conductive pattern to each other. Further, the conductive buffer layer 330 may have a material having predetermined elasticity so as to improve the contact stability between the connector and the conductive pattern.
[0060] In this embodiment, the conductive buffer layer 330 may be conductive rubber. The conductive rubber features both conductivity and elasticity, making it suitable for use as the conductive buffer layer.
[0061] The housing 350 of the mobile communication terminal may be manufactured by the in-molding labeling. That is, the carrier film that has the conductive pattern and the conductive buffer layer formed thereon is inserted into the mold for manufacturing the housing, and synthetic resins used to form the housing are injected into the mold, thereby manufacturing the housing. At this time, the carrier film 310 may be formed integrally with the housing 350 , and be formed on the surface of the housing.
[0062] In this embodiment, the carrier film 310 may be formed on an outer surface of the housing 350 . The conductive pattern 320 and the conductive buffer layer 330 may be formed between the housing 350 and the carrier film 310 .
[0063] In this embodiment, the mobile communication terminal may further include a connector 360 . The connector 360 may connect a board 370 with the conductive pattern 320 of the antenna that is formed on the surface of the housing 350 of the mobile communication terminal. The connector 360 may have predetermined elasticity.
[0064] The connector 360 may be fixed to the housing when the housing 350 of the mobile communication terminal is formed by the in-molding labeling.
[0065] Like this embodiment, when the conductive pattern 320 is formed on the outside of the housing 350 of the mobile communication terminal, and the connector 360 is used to connect the conductive pattern 320 to the board 370 inside the housing, the conductive pattern 320 on the surface of the housing may be deformed by the elasticity of the connector 360 . In this embodiment, the conductive buffer layer 330 is formed over the area of the conductive pattern that is in contact with the connector, thereby reducing a physical force that is directly applied to the conductive pattern due to the elasticity of the connector 360 .
[0066] FIG. 4 is a cross-sectional view illustrating a mobile communication terminal according to yet another exemplary embodiment of the invention.
[0067] Referring to FIG. 4 , a mobile communication terminal 400 according to this embodiment may include a carrier film 410 , a conductive pattern 420 , a conductive buffer layer 430 , an adhesive layer 440 , and a housing 450 of the mobile communication terminal.
[0068] The carrier film 410 may be formed of a material that is appropriate to perform in-molding labeling (IML). Specifically, the carrier film 410 that has the conductive pattern 420 formed on one surface thereof is inserted into a mold for manufacturing the housing of the mobile communication terminal, synthetic resins used to form the housing of the mobile communication terminal are injected into the mold, and the housing is molded from the synthetic resins at the appropriate temperature and pressure. The material that forms the carrier film 410 needs to be a material that does not undergo significant deformation under the pressure and temperature during the in-molding labeling, and at the same time, can be formed integrally with the housing of the mobile communication terminal. In this embodiment, the carrier film 410 may include a thin insulating polymer material.
[0069] The conductive pattern 420 may be an antenna pattern that is formed on one surface of the carrier film 410 .
[0070] The conductive pattern 420 may be formed by using various kinds of methods. First, a conductive pattern may be printed onto the carrier film 410 by using conductive ink. Alternatively, a desired pattern may be directly formed on the carrier film by sputtering or evaporation. The conductive pattern 420 may be a conductive pattern that is previously manufactured metal foil which is then attached to the carrier film 410 .
[0071] The conductive pattern 420 includes a power feed terminal, and may also include a connection terminal for providing an electrical connection to an external circuit, such as a ground terminal. In this embodiment, the power feed terminal may be a contact area where the conductive pattern is connected to an external power feed line.
[0072] The conductive buffer layer 430 may be formed at the contact area where the conductive pattern 420 can be connected to the external circuit. That is, the conductive buffer layer 430 may be formed at the area where the power feed terminal of the conductive pattern is formed.
[0073] A connector may be used to connect the conductive pattern 420 to a board. The conductive buffer layer 430 is formed at the area where the connector is in contact with the conductive pattern. The conductive buffer layer 430 may serve as a buffer between the connector and the conductive pattern. The use of the buffer layer 430 can improve contact stability between the connector and the conductive pattern.
[0074] The conductive buffer layer 430 may have conductivity since the conductive buffer layer 430 electrically connects the connector and the conductive pattern to each other. Further, the conductive buffer layer 430 may be formed of a material having predetermined elasticity so as to improve the contact stability between the connector and the conductive pattern.
[0075] In this embodiment, the conductive buffer layer 430 may be conductive rubber. The conductive rubber features both conductivity and elasticity, making it suitable for use as the conductive buffer layer.
[0076] The adhesive layer 440 may be formed between the conductive pattern 420 and the conductive buffer layer 430 . The adhesive layer 440 improves adhesive strength between the conductive pattern 420 and the conductive buffer layer 430 , thereby preventing separation of the conductive buffer layer 430 from the conductive pattern 420 during the in-molding labeling.
[0077] In this embodiment, copper foil tape may be used as the adhesive layer 440 .
[0078] When the copper foil tape is used, the copper foil tape 440 may be applied to the conductive pattern 420 , and the conductive buffer layer 430 may be applied to the copper foil tape. The copper foil tape has conductivity, and can strengthen the function of the conductive buffer layer 430 .
[0079] The housing 450 of the mobile communication terminal may be formed by the in-molding labeling. That is, the carrier film that has the conductive pattern and the conductive buffer layer formed thereon is inserted into the mold, and synthetic resins used to form the housing are injected into the mold, thereby manufacturing the housing. Here, the carrier film 410 may be formed integrally with the housing 450 and be formed on the surface of the housing.
[0080] In this embodiment, the carrier film 410 may be formed on an outer surface of the housing 450 . The conductive pattern 420 and the conductive buffer layer 430 may be formed between the housing 450 and the carrier film 410 .
[0081] In this embodiment, the mobile communication terminal may further include a connector 460 . The connector 460 may connect a board 470 disposed inside the housing with the conductive pattern 420 of the antenna that is formed on the surface of the housing 450 of the mobile communication terminal. The connector 460 may have predetermined elasticity.
[0082] The connector 460 may be fixed to the housing when the housing 450 of the mobile communication terminal is formed by the in-molding labeling.
[0083] Like this embodiment, when the conductive pattern 420 is formed on the outside of the housing 450 of the mobile communication terminal, and the connector 460 is used to connect the conductive pattern 420 to the board 470 inside the housing, the conductive pattern 420 formed on the surface of the housing may be deformed due to the elasticity of the connector 460 . In this embodiment, the conductive buffer layer 430 is formed over the area of the conductive pattern that is in contact with the connector, thereby reducing a physical force that is directly applied to the conductive pattern due to the elasticity of the connector.
[0084] As set forth above, according to exemplary embodiments of the invention, a film type antenna that has a contact structure to stably connect the film type antenna to a circuit of a board inside a mobile communication terminal, and a mobile communication terminal having the film type antenna.
[0085] While the present invention has been shown and described in connection with the exemplary embodiments, it will be apparent to those skilled in the art that modifications and variations can be made without departing from the spirit and scope of the invention as defined by the appended claims. | There is provided a film type antenna including: a carrier film; a conductive pattern provided on one surface of the carrier film; and a conductive buffer layer provided on one surface of the conductive pattern. | 7 |
PRIORITY CLAIM
[0001] This application is a Continuation application of, and claims the benefit of priority from, U.S. patent application Ser. No. 10/387,915 filed Mar. 13, 2003 and titled Audio Feedback Processing System, which is incorporated by reference. This application also claims the benefit of priority from U.S. Provisional Pat. App. Ser. No. 60/363,994, filed Mar. 13, 2002 and titled Employing Narrow Bandwidth Notch Filters In Feedback Elimination, which is also incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] This invention relates to feedback in audio systems. More particularly, this invention relates to identifying a feedback frequency in a signal and adaptively filtering the feedback frequency from the signal.
[0004] 2. Related Art
[0005] An audio system typically includes an input transducer (microphone), an amplifier, a microprocessor and an audio output (loudspeaker). The input transducer receives sound into the system, the amplifier amplifies the sound, the microprocessor performs signal processing, and the audio output (loudspeaker) provides sound to users of the system. Many audio systems allow for a duplex operation, where sound may be input to the microphone while audio is provided at the speaker. However, when the microphone receives a portion of the audio provided at the speaker as an input, an unstable, closed-loop system is created, resulting in audio feedback.
[0006] Audio feedback is manifested as one or more audio feedback signals at the speaker, where each feedback signal may be modeled as a sinusoidal signal (i.e. the feedback signal(s) exhibit characteristics of a sinusoidal signal). To eliminate a particular feedback signal, the microprocessor converts the audio signal into a discrete (sampled) frequency spectrum representation, such as a Discrete Fourier Transform (DFT), Spectral Estimation, Filter Banks, or like representation. The conversion of the audio signal to the sampled frequency spectrum allows for a general identification of the frequency of the feedback signal. The frequency sample having the greatest magnitude in the discrete frequency domain is selected as the frequency of the feedback signal.
[0007] A notch filter is placed at the identified frequency of the feedback signal to eliminate that particular feedback signal. However, because of computational and memory limitations of the microprocessor, the sampling resolution of the sampled frequency spectrum representation is limited. Thus, the selected frequency sample does not provide an accurate estimate of an actual frequency of the feedback signal. Because the selected frequency sample is not an accurate estimate, a notch filter is utilized that has a significantly wider bandwidth and/or a greater cut-depth than what is actually necessary for filtering the feedback signal. The wider bandwidth and/or greater cut-depth are necessary to ensure that the feedback signal is eliminated from the output signal. However, the use of a wider bandwidth and/or greater cut-depth notch filter can degrade the audio quality of the sound at the speaker.
[0008] The computational and memory limitations of the microprocessor limits the number of notch filters that may be used to eliminate audio feedback signals. Where the number of feedback signals exceeds the number of notch filters available, some of the feedback signals cannot be eliminated by the system. The failure to eliminate at least some of the feedback signals may require a system gain to be reduced, resulting in degraded system performance.
SUMMARY
[0009] This invention provides an audio system that identifies the frequency of a feedback signal using interpolative feedback identification. The interpolative feedback identification may be accomplished using frequency interpolation on a sampled frequency spectrum signal corresponding to a feedback signal. The feedback interpolation allows the frequency of the feedback signal to be identified, especially where the frequency of the feedback lies between samples of the frequency spectrum signal. The interpolation may include using samples of the sampled frequency spectrum signal to generate a unique quadratic (or higher order polynomial), which resembles the original main lobe of the feedback signal represented by the frequency spectrum signal. The polynomial may be constructed from the samples using polynomial interpolation, rational function interpolation, cubic spline interpolation, and the like. The peak of the polynomial and thus a representation/estimation of the actual frequency of the feedback signal may be determined, for example, by setting a derivative of the generated polynomial equation to zero. A narrowly tailored filter, such as a notch filter, may be placed at the determined frequency of the feedback to eliminate or reduce the feedback signal. The filter also reduces the effect on the audio signal quality provided by the audio system.
[0010] The audio system may adaptively filter multiple feedback signals using a single filter such as a notch filter. The adaptive filtering may include identifying frequencies of feedback in the audio signal, and determining which frequencies of feedback signals lie within a frequency window comprising adjoining samples of the sampled frequency spectrum. A filter, such as a notch filter is configured to filter out the frequencies identified as within a frequency range covered by the frequency window, thereby freeing-up notch filters for filtering other feedback signals, or for reducing memory and processing requirements for the microprocessor of the audio system. The frequency range covered by the frequency window may comprise any number of adjoining samples, and may be predetermined and/or configurable. Further, the frequency range covered by the frequency window may vary depending on the frequency band being examined, and/or the resolution of the sampled frequency spectrum.
[0011] Other systems, methods, features and advantages of the invention will be, or will become, apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the following claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The invention may be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like referenced numerals designate corresponding parts throughout the different views.
[0013] FIG. 1 is a block diagram of an audio system having feedback identification and reduction techniques.
[0014] FIG. 2 is a flow chart illustrating operation of the audio system of FIG. 1 in identifying the frequency of a feedback signal.
[0015] FIG. 3 is a graph illustrating a time-domain feedback signal.
[0016] FIG. 4 is a graph illustrating the Discrete Time Fourier Transform of the feedback signal of FIG. 3 .
[0017] FIG. 5 is a graph illustrating a time-domain window function.
[0018] FIG. 6 is a graph illustrating a Discrete Time Fourier Transform of the time-domain window function of FIG. 5 .
[0019] FIG. 7 is a graph illustrating the time-domain signal resulting from multiplying the feedback signal of FIG. 3 with the window function of FIG. 5 .
[0020] FIG. 8 is a graph illustrating the Discrete Time Fourier Transform of the windowed feedback signal of FIG. 7 .
[0021] FIG. 9 is a graph illustrating the Discrete Fourier Transform of the of the windowed feedback signal of FIG. 7 .
[0022] FIG. 10 illustrates an expansion of a portion of the graph of FIG. 9 , showing frequency bins which may be utilized in interpolating a frequency of a feedback signal.
[0023] FIG. 11 is a graph comparing characteristics of prior art notch filters with a notch filter configured using interpolative feedback identification.
[0024] FIG. 12 is another graph comparing characteristics of a prior art notch filter, with a notch filter configured using interpolative feedback identification.
[0025] FIG. 13 is a flow chart illustrating operation of the audio system of FIG. 1 for performing adaptive filtering.
[0026] FIG. 14 is a graph illustrating a frequency window covering a specified frequency range for a time-domain signal, which may be utilized in performing adaptive filtering.
[0027] FIG. 15 is a graph illustrating a frequency window covering a specified frequency range for a frequency-domain signal, which may be utilized in performing adaptive filtering.
[0028] FIG. 16 is a graph illustrating characteristics for two notch filters for filtering corresponding feedback signals.
[0029] FIG. 17 is a graph illustrating characteristics of a notch filter configured for adaptively filtering two feedback signals.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] FIG. 1 is a block diagram of an audio system 100 having feedback identification and feedback reduction or elimination techniques. The audio system uses interpolative feedback identification and may adaptively filter multiple feedback signals using one notch filter. The interpolative feedback identification provides for a single estimate of the feedback frequency achieved from more than one sample of a discrete frequency spectrum representation of a feedback signal. The interpolative feedback identification may include utilizing frequency interpolation by generating a second degree or higher polynomial using one or more samples of the discrete frequency spectrum representation. An accurate representation of the actual frequency of the feedback signal may be determined, for example, by setting a derivative of the polynomial to zero. A filter, such as a notch filter, may be placed in response to the interpolative feedback identification to reduce or eliminate the feedback signal with little or no effect on the audio signal quality provided by the audio system. The adaptive filtering involves configuring a filter, such as a notch filter, to eliminate multiple feedback signals, which allow other filters to reduce or eliminate other feedback signals. The adaptive filtering may also, or in the alternative, reduce processor memory and/or computational requirements of the audio system.
[0031] The audio system 100 includes an audio input, i.e. a microphone 102 , for receiving an audio signal. The microphone 102 is coupled with a microprocessor 104 , which is capable of controlling operation of the audio system 100 . The microprocessor 104 may perform any analog to digital conversions of audio signals received and digital signal processing. The microprocessor 104 is further capable of performing digital to analog conversions of audio provided by the audio system 100 . The microprocessor 104 is coupled with an amplifier 106 capable of amplifying an output audio signal. Amplifier 106 is coupled with a loudspeaker 108 for providing the output audio signal to a user of the audio system. While a particular configuration is shown, the audio system may have other configurations, including those with fewer or additional components.
[0032] FIG. 2 is a flow chart of a method for identifying and reducing and/or removing a feedback signal in an audio system. A time-domain audio signal s[n] from the microphone 104 is received 200 at microprocessor 104 . Audio feedback may result when one or more portions of the audio provided from loudspeaker 108 is received at microphone 102 , thereby causing an unstable, closed-loop system. Microprocessor 104 converts 202 the time-domain audio signal into a sampled frequency-domain signal |S(K)|. Microprocessor 104 may use windowing techniques such as Rectangular, Hamming, Bartlet, and like techniques to compute the frequency domain signal. The microprocessor 104 may then detect 204 the feedback. The detection of feedback may include performing frequency spectrum analysis such Discrete Fourier Transform (DFT), Spectral Estimation, Filter Banks, and like techniques. Samples of the frequency domains signal may be used in interpolating 206 to determine the frequency of the feedback signal, and the feedback signal may be filtered 208 . Interpolating 206 and filtering 208 will be discussed further below with respect to FIG. 10 .
[0033] FIGS. 3-10 illustrate detecting of the feedback signal by microprocessor 104 . FIG. 3 illustrates a time-domain feedback signal s[n]. FIG. 4 illustrates a frequency domain signal |S(e jw )| resulting from converting the feedback signal s[n] to the frequency domain using, for example, the Discrete Time Fourier Transform (DTFT). FIG. 5 illustrates a time-domain window function w[n]. FIG. 6 illustrates the DTFT(|W(e jw )|) of the window function w[n]. FIG. 7 illustrates the product of the time-domain feedback signal s[n] with the time-domain window function w[n]. FIG. 8 illustrates the windowed frequency domain signal |Ŝ(e jw )| centered about the frequency domain feedback signal |S(e jw )|, resulting from taking the DTFT of the product of s[n] and w[n]. FIG. 9 illustrates the sampled frequency domain signal |Ŝ[k]| resulting from taking the DFT of the product of s[n] and w[n]. This is, for example, equivalent to sampling the windowed frequency domain feedback signal |Ŝ(e jw )| of FIG. 8 at equally spaced frequency intervals. FIG. 10 illustrates a portion of the sampled, windowed frequency domain signal |S[k]| of FIG. 9 , specifically showing a more detailed view around a main lobe of the feedback signal. The frequency spectrum signals illustrated in FIGS. 4, 6 and 8 are DTFT. The frequency spectrum signals illustrated in FIGS. 9 and 10 are DFTs. Other frequency spectrum analysis techniques may be utilized in converting the time-domain signal to the frequency domain, and analyzing the frequency domain signal.
[0034] In the flowchart of FIG. 2 , the interpolating 206 provides a single representation/estimation of a feedback frequency determined from multiple samples of the discrete frequency spectrum representation of the frequency signal. The interpolative feedback identification may be determined using frequency interpolation techniques, for example, as will be described with respect to the graph of FIG. 10 , where each frequency sample defines a frequency bin. The notations used in FIG. 10 are as follows:
[0035] B estimate =The estimated frequency of the feedback signal.
[0036] B p =Peak (maximum) bin number.
[0037] B p−1 =Bin just below (in frequency) the peak bin number.
[0038] B p+1 =Bin just above (in frequency) the peak bin number.
[0039] A estimate =Amplitude at the estimated frequency of the feedback.
[0040] A p =Amplitude of the peak bin.
[0041] A p−1 =Amplitude of the bin just below (in frequency) the peak bin.
[0042] A p+1 =Amplitude of the bin just above (in frequency) the peak bin.
[0043] B estimate is the estimated frequency of the feedback signal which may be determined using the interpolation techniques described below. Ideally, the frequency B estimate will coincide with the actual frequency of the feedback signal. In any event, the frequency B estimate is typically a more accurate estimate of the actual frequency of the feedback signal than the frequency B p which is selected by systems of the prior art.
[0044] Interpolative feedback identification such as frequency interpolation provides a more accurate estimate of the actual frequency of feedback, and may be determined using samples of the DFT |S[k]|. Using the samples of the DFT signal |S[k]|, a unique quadratic (or higher order polynomial) may be generated which resembles the original main lobe of the DTFT representing the feedback signal. A polynomial may be reconstructed from the sample points of the DFT |S[k]|. An interpolating polynomial for degree N−1 is illustrated as a LaGrange polynomial by:
P ( x ) = ( x - x 2 ) ( x - x 3 ) … ( x - x N ) ( x 1 - x 2 ) ( x 1 - x 3 ) … ( x 1 - x N ) y 1 + ( x - x 1 ) ( x - x 3 ) … ( x - x N ) ( x 2 - x 1 ) ( x 2 - x 3 ) … ( x 2 - x N ) y 2 + … + ( x - x 1 ) ( x - x 2 ) … ( x - x N - 1 ) ( x N - x 1 ) ( x N - x 2 ) … ( x N - x N - 1 ) y N
[0045] Other interpolating polynomial techniques may be used, including polynomial interpolation, rational function interpolation, cubic spline interpolation and the like.
[0046] Applying the LaGrange polynomial equation to frequency interpolation (here, for a 2 nd order quadratic) yields a feedback frequency f(B) of:
f ( B ) = ( B - B P ) ( B - B P + 1 ) ( B P - 1 - B P ) ( B p - 1 - B P + 1 ) A P - 1 + ( B - B p - 1 ) ( B - B P + 1 ) ( B P - B P - 1 ) ( B P - B P + 1 ) A P + ( B - B P - 1 ) ( B - B P ) ( B P + 1 - B P - 1 ) ( B P + 1 - B P ) A P + 1
[0047] A peak of the quadratic curve, and thus an estimate/representation of the frequency of the feedback signal may be determined by solving for a maximum of f(B). Solving for the maximum may be accomplished, for example, by taking the derivative of f(B), and setting the derivative to zero, yielding the estimated feedback frequency B estimate as:
B estimate = ⌊ A P - 1 * ( B P + B P + 1 ) ( B P - B P - 1 )
( B P - B P + 1 ) ( B P + 1 - B P - 1 ) ( B P + 1 - B P ) ⌋ 2 + ⌊ A P * ( B P - 1 + B P + 1 ) ( B P - 1 - B P )
( B P - 1 - B P + 1 ) ( B P + 1 - B P - 1 ) ( B P + 1 - B P ) ⌋ 2 + ⌊ A P + 1 * ( B P - 1 + B P ) ( B P - 1 - B P )
( B P - 1 - B P + 1 ) ( B P - B P - 1 ) ( B P - B P + 1 ) ⌋ 2
[0048] The pole of the quadratic curve provides a more accurate representation of the frequency of the feedback signal than the frequency B p of the peak bin alone. Where it is known that, prior to the interpolation, A p is greater than both A p+1 , and A p−1 , it may be determined that the interpolated polynomial has no minimum at this location, and only a maximum. Thus, taking the derivative of the interpolation polynomial and setting it to zero yields the maximum, and thus the more accurate representation of the frequency of the feedback signal than the frequency B p . However, where it is not known prior to the interpolation that A p is greater than both A p+1 , and A p−1 , the system may verify that the frequency at B estimate is a maximum and not a minimum of the quadratic equation.
[0049] To determine that the frequency at B estimate is a maximum (and not a minimum) of the quadratic equation, a value A estimate may be computed by the microprocessor 104 using the equation for f(B) above, representing the amplitude of the feedback signal at the interpolated frequency B estimate . A estimate may be compared with the values A p+1 and A p−1 , which are amplitudes of the feedback signal at corresponding frequencies B p and B p+1 , to ensure that A estimate has the highest amplitude.
[0050] The interpolating 206 of FIG. 2 provides a more accurate estimate of the actual frequency of feedback signal. Using the frequency estimate B estimate , a filter may be configured for filtering 208 the feedback of the audio signal. The filter may be a bandwidth notch filter. Other filters may be used. Since a close estimate for the frequency of the feedback signal has been identified using frequency interpolation, the bandwidth notch filter may be configured (i.e., coefficients calculated therefore including Quality Factor and/or gain/cut-depth) by the microprocessor 104 as a narrow bandwidth notch filter capable of filtering-out the frequency of the feedback signal. The microprocessor 104 may also minimize at least one of a bandwidth and a cut-depth of the notch filter. The configured filter may then be placed at the frequency B estimate (i.e. designed with a center frequency of B estimate ). Such filtering may be employed utilizing filtering techniques such as Finite Impulse Response (FIR) and Infinite Impulse Response (IIR) techniques, or any other filtering technique sufficient for filtering out the feedback signal as would be appreciated by one skilled in the art. Thus, identifying the frequency of the feedback signal using interpolative feedback identification allows for more accurate placement of the notch filter at the frequency of the feedback signal, and thus is more accurately configured for filtering-out the feedback signal.
[0051] FIG. 10 illustrates an example of interpolation by generating a polynomial which models the original main lobe of the frequency spectrum, where the interpolation is carried-out by solving for a maximum of the polynomial by derivation. One skilled in the art would realize that any interpolation techniques may be utilized to identify the feedback frequency. For example, additional frequency bins may be interspaced between samples of the sample frequency domain signal shown in FIG. 10 , each interspaced bin having zero energy value. The sampled frequency domain signal may then be passed through a low pass filter resulting in an interpolated sampled spectrum. Using the interpolated sampled spectrum, one could identify a maximum of the filtered frequency spectrum to obtain a more accurate estimate of the feedback signal frequency.
[0052] FIGS. 11 and 12 illustrate graphs comparing characteristics of prior art notch filters with notch filters configured in accordance with interpolative feedback identification. The sampled frequency bin having a maximum amplitude B p in FIG. 10 , may correspond to 994 Hz in FIGS. 11 and 12 . A more accurate representation of the frequency of the feedback signal, B estimate in FIG. 10 , may correspond to 1000 Hz in FIGS. 11 and 12 . The sampled frequency bins and frequency of the feedback signal may have other frequencies. As shown at FIGS. 11 and 12 , prior art feedback identification techniques result in a notch filter being configured to filter out frequencies at the maximum bin frequency 994 Hz, and thus must have an increased bandwidth as shown by line 1100 FIG. 11 , or increased cut-depth as shown by line 1200 of FIG. 12 , to ensure that the gain (G) of the filter at the actual frequency of the feedback is sufficient for filtering the feedback signal.
[0053] In contrast, feedback identification techniques using interpolative feedback identification provide a more accurate representation (here about 1000 Hz) of the actual frequency of feedback. Accordingly, a notch filter having characteristics shown at 1105 and 1205 of FIGS. 11 and 12 may be placed at the more accurate estimate for the actual frequency of the feedback signal. Because the filter is more accurately placed, it may be more narrowly tailored (i.e. reduced bandwidth and/or cut-depth) while ensuring that the gain is sufficient at the frequency of the feedback signal to eliminate or reduce the feedback signal, and having little or no effect on the quality of the signal provided at the loudspeaker 108 , or in any event, less of an effect on the audio quality than notch filters configured using prior art feedback identification techniques.
[0054] FIG. 13 is a flow chart of a method for providing adaptive filtering of feedback in an audio system. Frequencies of a plurality of feedback signals are identified/estimated 1300 by the microprocessor 104 . Such frequencies may be identified as described above using interpolative feedback identification, or in any other fashion. The microprocessor 104 determines 1302 whether the frequencies of feedback signals are within a frequency window covering a specified frequency range. The frequency range covered by the frequency window may be predetermined and/or configurable, and may vary depending on the frequency band being examined. The specified frequency range covered by the frequency window will be discussed further below with respect to FIGS. 14 and 15 .
[0055] The microprocessor 104 filters 1304 the feedback signal within the frequency range covered by the frequency window. The microprocessor 104 configures a filter for filtering out any frequencies a feedback signal determines to be within the frequency range. The filter may be a notch filter or other type of filter. The microprocessor may determine filter coefficients such as quality factor, cut-depth and a center frequency for the filter.
[0056] FIG. 14 is a graph illustrating a frequency window covering a specified frequency range for time-domain representations of feedback signals, which may be utilized in providing the adaptive filtering discussed above with respect to FIG. 13 . As shown in FIG. 14 , a frequency window represented generally at 1405 may cover a specified frequency range, for example, αf. Where two feedback frequencies, for example feedback frequency f 1 and feedback frequency f 2 lie within the frequency window 1405 , it may be determined 1302 that adaptive filtering will be utilized to configure a single filter to filter out the feedback frequencies.
[0057] To determine whether the feedback frequencies lie within the frequency window 1405 , a frequency differential Δf may be determined between feedback frequencies, for example by subtracting one frequency from another. For example, as shown in FIG. 14 , Δf may be determined by subtracting the frequency f 1 representing a first frequency at which feedback is located from f 2 representing a second frequency at which feedback is located. Where the value Δf is less than αf, and thus the frequency range covered by the frequency window 1405 , it may be determined that the feedback located at frequencies f 1 and f 2 may be adaptively filtered by a single filter.
[0058] A filter may be configured, for example by the microprocessor 104 at a center frequency fc within the frequency window 1405 having sufficient quality factor and/or cut-depth to filter out the feedback at the frequencies f 1 and f 2 .
[0059] Concurrently or subsequently, if a feedback signal is identified as being located at a frequency f 3 , for example as shown in FIG. 14 , the microprocessor 104 may determine whether the frequency differential Δf between f 3 and fc is less than the frequency range Δf covered by the frequency window 1405 . Where it is determined that the newly calculated Δf is less than αf, the microprocessor 104 may determine that the feedback identified at f 3 may be adaptively filtered utilizing the filter at fc, and thus reconfigure the filter centered at fc (i.e., reconfigure the quality factor, cut-depth and/or fc) to filter out the feedback identified at the frequencies f 1 , f 2 and f 3 .
[0060] Alternatively, instead of determining the frequency differential between f 3 and fc, the microprocessor 104 may instead determine a frequency differential Δf between f 3 and f 1 for comparing with the frequency range αf of the frequency window 1405 in determining whether the feedback frequencies f 1 , f 2 and f 3 may be adaptively filtered by a single filter. As additional feedback frequencies are concurrently and/or subsequently identified, the microprocessor 104 may determine whether to employ additional filters, or to utilize existing filters to cover the concurrently or subsequently identified frequencies of feedback.
[0061] In addition, the microprocessor 104 may further utilize algorithms that may minimize the number of filters necessary to filter out the identified feedback frequencies. In FIG. 14 , the frequency of the feedback frequency f 1 may be 10000 Hz, where the feedback frequency f 2 may be 1012 Hz and the feedback frequency f 3 may be 1024 Hz. The specified frequency range αf of the frequency window 1405 may be any value, for example, 6 Hz, 12 Hz, 20 Hz, 100 Hz or any other value. The specified frequency range αf may vary across the frequency spectrum, as a function of the frequency of the particular feedback frequencies being examined. For example, the frequency range αf may increase logarithmically as the particular frequency being examined for feedback increases. Thus, at lower frequencies, αf may have a smaller value than αf at higher frequencies. In addition, the value of αf defining the frequency window 1405 may be configurable by a user of the system 100 .
[0062] The graph of FIG. 14 describes how the determining 1302 may be accomplished for feedback signals represented in the time-domain. The determining 1310 may similarly be carried-out for identified feedback signals in the frequency domain, for example as described with respect to the graph of FIG. 15 .
[0063] FIG. 15 is a graph illustrating a frequency window covering a specified frequency range for frequency domain representations of feedback signals, which may be utilized for the adaptive filtration discussed above. A frequency window 1505 is shown, covering a specified frequency range represented by a particular number of frequency bins (i.e., frequency samples) αB. To determine 1302 whether the feedback frequencies lie within the frequency window 1505 , a frequency differential represented here as a number of frequency bins, ΔB, may be determined between feedback frequency bins, for example by subtracting one feedback frequency bin from another. As shown in FIG. 15 , ΔB may be determined by subtracting the frequency bin# B 328 representing a first frequency at which feedback is located from the frequency bin# B 326 representing a second frequency at which feedback is located. Where the value ΔB is less than αB, and thus the frequency range covered by the frequency window 1505 , it may be determined that the feedback located at frequency bins B 328 and B 326 may be adaptively filtered by a single filter.
[0064] A filter may be configured, for example by the microprocessor 104 at a center frequency fc within the frequency window 1505 having sufficient quality factor and/or cut-depth to filter out the feedback at the frequency bins B 326 and B 328 .
[0065] Concurrently or subsequently, if a feedback signal is identified as being located at a frequency bin #B 333 , for example as shown in FIG. 15 , the microprocessor 104 may determine whether the frequency differential ΔB between the frequency bin #B 333 and fc is less than the specified frequency range αB covered by the frequency window 1505 . Where it is determined that the newly calculated ΔB is less than αB, the microprocessor 104 may determine that the feedback identified at frequency bin #B 333 may be adaptively filtered utilizing the filter at fc. The microprocessor 104 may reconfigure the filter centered at a center frequency fc (i.e., reconfigure the quality factor, cut-depth and/or fc) to filter out the feedback identified at the frequencies represented by frequency bins 326 , 328 and 333 . In FIG. 15 , the center frequency fc is shown, by example, at bin #B 327 .
[0066] Similar to as discussed above with respect to FIG. 14 , instead of determining the frequency differential between bin #B 333 and fc, the microprocessor 104 may instead determine a frequency differential ΔB between bins B 333 and B 326 . This frequency differential ΔB may be compared with the frequency range αB of the frequency window 1505 to determine whether the feedback frequencies represented at bins B 326 , B 328 and B 333 may be adaptively filtered by a single filter. As additional feedback frequencies are concurrently and/or subsequently identified, the microprocessor 104 may determine whether to employ additional filters, or to utilize existing filters to cover the concurrently or subsequently identified frequencies of feedback.
[0067] Additionally, and as discussed above, the microprocessor 104 may further utilize algorithms that may minimize the number of filters necessary to filter out the identified feedback frequencies. The specified frequency range αB of the frequency window 1505 is shown in FIG. 15 as being 3 frequency bins, where the bin # 326 may represent a frequency sample at 1000 Hz, and spacing between frequency samples/bins may be approximately 6 Hz. However, similar to as discussed above with respect to FIG. 14 , it will be appreciated by one skilled in the art that αB may be any number of frequency bins, for example 2, 3, 5 or 10 frequency bins, and that the frequency differential represented by αB may vary as a function of the feedback frequencies being examined. In addition, the value of αB defining the frequency window 1505 may be configurable by a user of the system 100 .
[0068] FIG. 16 illustrates a graph showing characteristics of adjacently placed notch filters that may benefit from the adaptive filtering discussed herein. Feedback has been identified at frequencies of f 1 equal to about 1000 and f 2 equal to about 1012 Hz. To eliminate the feedback identified at these frequencies, notch filters may be utilized having the characteristics 1600 and 1605 . The characteristics 1600 include a Quality Factor equal to about 128 and a cut-depth equal to about −6 dB to eliminate or reduce the feedback. The characteristics 1605 include a Qualify Factor equal to about 128 and a cut-depth equal to about −6 dB to eliminate or reduce the feedback. However, in utilizing adaptive filtering, microprocessor 104 is capable of determining that the frequency differential Δf between feedback frequencies at frequencies f 1 and f 2 are within a frequency range αf defining a frequency window, where αf may be 15 Hz. Microprocessor 104 may configure a single notch filter to filter out the feedback from both identified feedback frequencies.
[0069] In FIG. 17 , characteristics of a notch filter configured by the microprocessor 104 is shown at 1700 . The characteristics indicate a notch filter designed for a center frequency fc of about 1006 Hz and having a Quality Factor of equal to about 45, and a cut-depth equal to about −6 dB. The notch filter is placed between the two identified frequencies, here f 1 at about 1000 Hz and f 2 at about 1012 Hz, to filter out the feedback signal frequencies. The notch filter may be placed (i.e. designed with a center frequency) at a midpoint of the frequencies of identified feedback, here about 1006 Hz. The notch filter may be placed at any other frequency between the identified feedback frequencies, or within the frequency window being examined (not shown), sufficient for filtering out the identified feedback. Where more than two frequencies of feedback signals are determined to fall within the frequency range αf, an average frequency may be calculated for the determined frequencies of feedback, where the filter is placed at the average frequency. Alternatively, a midpoint frequency between the greatest and lowest frequencies determined to be within the frequency range αf defining the frequency window may be selected for placement of the notch filter.
[0070] Thus, instead of requiring two or more notch filters to filter out multiple feedback signals within the frequency window defined by the frequency range αf, a single notch filter may be utilized. Hence, the other notch filter(s) available in the audio system may be used to eliminate or reduce feedback at other frequencies. Rather than having additional notch filters, reducing the number of notch filters for filtering feedback signals may reduce the memory and/or processing requirements of microprocessor 104 . The filtering may be accomplished as software executed on the microprocessor 104 .
[0071] Further, multiple sets of frequencies of feedback signals may be identified by the microprocessor 104 , where the microprocessor 104 configures a notch filter to filter the feedback signals corresponding to each set of feedback frequencies.
[0072] The audio system 100 discussed above may be utilized in cellular telephones, public address systems, speakerphones having duplex operation, or any other audio system that may suffer from feedback. The microphone 102 may be any input transducer sufficient for receiving audio into the audio system 100 . The microprocessor 104 may be any microprocessor capable of performing the functionality/processing, including converting time-domain signals to sampled frequency domain signals. Further, although not shown, the microprocessor 104 may include, or may be coupled with, an external storage media such as computer memory that may include computer programming, executable on the microprocessor 104 , for carrying out one or more of the functionalities described herein. The storage medium may be magnetic, optical or any other storage media capable of providing programming for the microprocessor 104 .
[0073] The loudspeaker 108 may be any speaker capable of providing the output audio from the audio system 100 . Alternatively, hardware components not shown may be coupled with the microprocessor 104 for performing the sampled frequency domain conversion where the microprocessor 104 does not possess such functionality. The filtering may be accomplished using software, hardware or a combination, and need not be limited to notch filtering techniques. The software may be executable on a microprocessor such as performing digital signal processing or the like. The hardware may be coupled with the microprocessor 104 , which may configure the hardware to achieve desired processing and/or filtering characteristics.
[0074] In addition, the values illustrated and discussed in relation to the Figures are exemplary, and are not limitations on the feedback identification and elimination or reduction system. Further, the value for the frequency range αf with respect to adaptive filtering may be any value while achieving at least some of the advantages discussed herein. The frequency range αf/αB may be increased (made larger) to reduce the number of filters required to eliminate feedback. A lower number of filters may be desired where the number of feedback signals outnumber the number of filters available for filtering feedback, or where a processor performing the filtering has limited memory and/or processing capabilities. The frequency window defined by the frequency range αf/αB may be determined based on considerations within the particular audio system utilized, and may be user-configurable. Such considerations may include selection of a frequency range which allows frequencies of feedback signals to be combined without unduly affecting the audio quality provided by the audio system. However, different audio systems have varying requirements as to the audio quality provided thereby. For example, a public address system may have less stringent audio quality requirements than an audio system that may be used in a concert hall or the like. A larger frequency range value αf/αB may be desired for the former than for the latter to account for desired audio quality.
[0075] Further, one skilled would realize that various techniques may be employed in identifying which frequencies of feedback within the frequency range αf/αB. Further, the microprocessor may utilize various techniques in grouping identified feedback signal sets which are each to be filtered by a single filter, where the technique may minimize the number of filters required for filtering the identified feedback signals.
[0076] The audio system 100 may perform both interpolative feedback identification in identifying frequencies of feedback signals, and adaptive filtration for configuring a filter-to-filter out multiple frequencies of feedback signals. The audio system 100 need not perform the feedback identification using interpolative feedback identification and/or the adaptive filtering. Rather, the audio system 100 may be utilized in identifying the frequencies of feedback using interpolative feedback identification while being coupled with additional hardware or microprocessing capabilities which are utilized in eliminating or reducing the identified frequencies of feedback. The hardware may include adaptive filtering. Further, the audio system 100 may perform adaptive filtering using frequencies of feedback identified by external hardware or a processing functionality (which may or may not include feedback frequencies identified using the interpolative feedback identification).
[0077] The illustrations have been discussed with reference to functional blocks identified as modules and components which may be combined or further sub-divided. In addition, while various embodiments of the invention have been described, it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible within the scope of the invention. Accordingly, the invention is not to be restricted except in light of the attached claims and their equivalents. | A signal processing system improves signal quality by accurately locating and eliminating a feedback signal in an input signal, such as an audio signal. The signal processing system interpolates between frequency sample points to obtain a more accurate identification of a feedback signal frequency. A less intrusive filter reduces or eliminates the identified frequency signal frequency without excessive adverse effects on adjacent frequencies in the input signal. | 7 |
BACKGROUND OF THE INVENTION
Containers for storing or transporting powdered or granular commodities frequently employ pneumatic conveyors to facilitate movement and discharge of the commodity. Gas pervious membranes, such as canvas or other fabrics, are commonly used to diffuse and direct the flow of fluidizing gas into the commodity. However, such membranes require complicated and costly mechanical devices to hold them in place, and they can not be cleaned simply by hosing down with water. Also, they are frequently clogged by powdered commodities or the fines of granular materials. This sometimes prevents their use in railroad vehicles. Prior art pneumatic conveyors using gas impervious membranes possess serious deficiencies when fluidizing gas flow has to be accurately controlled for long distances, or has to be readily changeable for different commodities or conditions.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the invention to provide an improved arrangement for conveying and discharging a powdered or granular material.
Another object is to provide a container with a pneumatic discharge device that is not clogged by powdered material.
Another object is to provide a pneumatic conveyor with a gas flow space that can be accurately controlled for long distances and which can be easily changed when required.
Another object is to provide a transportable container for powdered or granular material with a pneumatic discharge arrangement that is inexpensive to clean and maintain.
Another object is to provide a pneumatic conveyor and discharge system that is usable over a wide range of temperatures, pressures, product densities and particle sizes.
Another object is to provide an enclosed railroad vehicle for powdered or granular commodities with a fluidized discharge system which is relatively inexpensive, durable, easily changed for different commodities, and which does not possess defects found in similar prior art systems.
Other objects and advantages of the invention will be found in the specifications and claims and the scope of the invention will be pointed out in the claims.
DESCRIPTION OF THE DRAWING
FIG. 1 is an elevational view of a railroad tank car constructed in accord with the invention.
FIG. 2 is an enlarged cross sectional view taken along the line 2--2 in FIG. 1.
FIG. 3 is a partially broken away bottom view of the invention.
FIG. 4 is a cross sectional view taken along the line 4--4 in FIG. 3.
FIG. 5 is a cross sectional view, corresponding to FIG. 2, of another embodiment of the invention.
FIG. 6 is a partially broken away side view of the embodiment of FIG. 5.
FIG. 7 is an end view of the inner clamping member of the embodiment of FIG. 5.
FIG. 8 is a side view of the end of the clamping member shown in FIG. 7.
DESCRIPTION OF THE INVENTION
This invention may be used as a pneumatic conveyor, or to promote fluidized discharge from a stationary storage container, but the invention is especially useful in sealed railroad tank cars for powdered materials such as cement having essentially the structure disclosed in application for U.S. Pat. Ser. No. 561,143 filed Mar. 3, 1975, now abandoned, and assigned to the same assignee as this invention. Such a tank car 10 has an elongated metal body 11 supported at its opposite ends through a bolster-shear plate-draft sill assembly 13 on wheel trucks 14 of conventional construction. Body 11 has a lower portion formed from a pair of V-shaped hopper or trough sections 16 which slope downwardly at a predetermined angle (e.g., 10° ) from each end of the car to meet at the center of the car. A pair of assymetric truncated cone sections 17 are secured to the upper edges of hopper sections 16 so as to form the upper portions of the car.
Hopper sections 16 are formed from side wall plates 18 extending downwardly toward each other at a predetermined angle (e.g., 60° ). The lower edges of plates 18 are secured to each other by flat bottom closure plates 19 which meet and terminate adjacent a bottom outlet opening 21 at the center and lowermost location of car 10. A conventional valve assembly 22 controls discharge flow through opening 21. Side stiffener channels 23 may be secured at intervals along plates 18. End sheets 24 close off the ends of body 11. Car 10 should include other necessary conventional accessories such as top inlet openings 25 with hatch covers 26, couplers, etc., and a complete description of the car may be obtained from the aforementioned application for U.S. Pat. Ser. No. 561,143.
Car 10 is equipped with a system for discharging and conveying a powdered or granular commodity by fluidizing in accord with the teachings of this invention, the preferred embodiment being shown in FIGS. 1-4. Pairs of separate, correspondingly U-shaped clamping members 31 and 32 lie in the bottom of the hopper troughs defined by sloping side wall plates 18. Lower member 32 is nested within upper member 31, and each pair of clamping members extends for a substantial distance (e.g., 14 feet) along a bottom plate 19. Members 31 and 32 are removably attached to plate 19 by nuts 33 threaded on to studs 34 which may be threaded into tapped holes in plate 19. The lower terminal edges of members 31 and 32 are spaced a slight distance above plates 19 by sleeves 36 which receive studs 34. Studs 34 and their telescoped sleeves 36 are spaced in pairs or staggered at intervals along plates 19 so as to accurately define a pair of long gas gaps 37 of predetermined size (e.g. one-eighth inch) on opposite sides of the clamping members. Sleeves 36 may be welded to member 32 as shown or may be unattached to facilitate changing the size of gaps 37 replacement with sleeves of different length. A continuous sheet 38 of thin, flexible, gas-impervious material (e.g., natural rubber one-fourth inch thick) is securely clamped and immobilized between each pair of clamping members 31 and 32. Perforations in sheets 38 permit studs 34 to pass therethrough. Edge portions 39 of each sheet 38 protrude beyond each side of members 31 and 32 into contact with bottom plate 19 so as to seal the entire length of both gaps 37, and thus prevent the commodity in car 10 from escaping into the enclosed space under members 31 and 32. The legs 41 of upper clamping member 31 diverge downwardly at a slightly smaller angle than the corresponding legs of member 32 in order to ensure pressure on sheet 38 that will keep seal portions 39 tight against plate 19. The central portion 42 of member 31 is curved slightly downwardly toward member 32 to ensure sealing around studs 34 by squeezing sheet 38 therebetween. As shown in FIG. 4, adjacent pairs of clamping members 31 and 32 may be spaced slightly from each other. An end closure piece 43 spans the inside of each inner member 32 at each end and seals off the end of such member 32. An inwardly directed ledge 44 on each closure piece 43 rests on a rubber spacer 45 so as to complete the end seal and to help maintain the accuracy of gaps 37 at the ends of members 31 and 32.
A pressurized gas (e.g., air at from about 5 to 30 p.s.i.) is forced into the sealed space beneath each member 32 through a plurality of spaced gas inlet conduits 46 which extend into holes 47 through plates 19. Each conduit 46 is connected to a lateral pipe 48 which branches off a gas distribution header 49 which is connected to a pressurized gas inlet pipe 51. Control and check valves 52 regulate the flow into each lateral pipe 48, and a master control valve 53 regulates the flow from a suitable source of pressurized gas.
Another embodiment of the invention shown in FIGS. 5-8 is identical to the embodiment of FIGS. 1-4, except as noted herein. A flat plate 56 is attached to side wall plates 18 above bottom plate 19. This permits the discharge angle of the material conveying surface at the bottom of the car to be different (e.g., 8°-12° ) from the angle of bottom plates 19. Pairs of separate correspondingly V-shaped clamping members 57 and 58 lie in the bottom of the hopper troughs defined by plates 18. Lower member 58 is nested within upper member 57. Members 57 and 58 are removably attached to plate 56 by nuts 59 threaded on studs 60 which are attached to plate 56. Each nut 59 bears against a circular washer 61 which is received in notch 62 in upper member 57. A plurality of round spacer lugs 63 attached at intervals to the under side of member 58 raise the lower terminal edges of members 57 and 58 slightly above plate 56 so as to define a pair of long gas gaps 64. A sheet 65 of gas-impervious material having sealing edge portions 66 is tightly clamped between members 57 and 58 so as to seal gaps 64, as previously described with reference to the embodiment of FIGS. 1-4. A closure piece 67 seals off both ends of each member 58, and an inwardly directed ledge 68 on each piece 67 seals and maintains proper air gap spacing as previously described. Pressurized gas is fed into the sealed spaces under members 58 through a plurality of spaced conduits 69 connected to laterals 48 and passing through holes 70 in plates 19 into openings 71 in plates 56.
Tank car 10 may be unloaded in known manner by connecting one or more hose couplings to discharge outlet 21 and connecting a supply of pressurized gas to opened inlet pipe 51. When a predetermined gas pressure is attained in body 11, control valve 22 is opened and the fluidized commodity is pumped under pressure through outlet 21 to a designated receiver, which may be at a higher elevation than car 10. Gravity discharge from car 10 may be achieved simply by opening valve 22 and one or more hatch covers 26. Then sufficient pressurized gas is pumped through inlet 51 to keep the commodity flowing through outlet 21. The gas flow to various areas of car 10 is controlled by valves 52. Sealing edge portions 39 and 66 flutter and vibrate along their entire length thus creating turbulence which promotes fluidized flow and thus breaking up any material clogs or bridges.
It has thus been shown that by the practice of this invention a railroad car can be provided with a durable, easily cleaned and easily changeable gas discharge system. The inside of car 10 can be cleaned simply by hosing with steam, water or a cleaning solution, or the clamping members 31 and 32 or 57 and 58 and the vibrating sheets 38 or 65 can be removed by detaching nuts 33 or 59 and removing the entire assembly through the top hatches 25 when more thorough cleaning or maintenance is necessary. Any material which has caked on sealing edge portions 39 or 66 can be flaked off by blowing air through the system so as to vigorously vibrate the sheets. Gas gaps 37 and 64 can be changed easily for products of different density, moisture content, or flow characteristics, or for use of car 10 with different commodity receiving systems, simply by replacing sleeves 36 with other sleeves 36 of different lengths, or by replacing specific clamping members 58 with other members 58 having lugs 64 of a different diameter; rubber spacers 46 should be replaced if necessary with other spacers 46 of different thickness.
While the present invention has been described with reference to particular embodiments, it is not intended to illustrate or describe herein all of the equivalent forms or ramifications thereof. Also, the words used are words of description rather than limitation, and various changes may be made without departing from the spirit or scope of the invention disclosed herein. It is intended that the appended claims cover all such changes as fall within the true spirit and scope of the invention. | An enclosed container for transporting a powdered material is aerated by a pressurized gas which is forced between a long sheet of flexible, gas-impervious material and a sloping surface of the container. The sheet material is held in place by a pair of clamps which accurately control the size of the space through which the gas flows so as to cause the sheet material to vibrate or flutter over a relatively long distance. | 1 |
SUMMARY OF THE INVENTION
This invention permits to impede present easiness for industrial spying or else by means of document reproduction or remote-diffusion devices. It permits, by the coupling between, on the one hand, the creation of complementary graphic elements in the document and, in the other hand, the conception of adapted methods:
forbidding or controlling the production or the diffusion of certain sensitive documents,
altering according to predetermined guidelines the copy of some documents having a intrinsic value in order to facilitate the distinction between the original and its copy,
authorizing the reproduction or diffusion of some documents provided the payment of expenses relative to author's rights,
authenticating an original paper or its copy by means of a direct reproduction of the electronic original detained by the original emitter,
producing from an paper original an electronic copy or making an electronic transaction controlled by the emitter of the original document,
producing a copy of the whole or a part of a global document from an excerpt of this one.
To these purposes, the present invention centralizes the following functions:
Acquiring the document and expressing of a reproduction request,
Processing the acquired document for detecting the sensitive character in the document and, should the occasion arise, extracting the reproduction rules linked to the document,
managing and applying the reproduction rules,
producing the copied document, and, in some cases, producing a electronic copy or carrying out an electronic transaction, according to the reproduction rules and the expressed request; if required by searching the electronic original.
Today, in the different characteristic elements of document making or reproduction, there are some risks linked to the confidentiality of the information contained in the document or in the use of the produced document:
A--Any paper document from a company can be easily and quickly copied by means of a copy machine within the company. The copy can be easily moved outside the company to its detriment and without any trace, since there is no disappearance of the original.
B--Any document from a company can be remote reproduced by means of facsimile systems and without any trace of this leak nevertheless very harmful to the company.
C--Color reprography systems today permit and increasingly will permit, by means of the integration of more and more efficient technologies, to get copies very faithful to the original, making the differentiation between the copy and the original difficult without having recourse to a more and less extensive expertise.
D--The photocopies of administrative, financial or transactions-related documents can cause, by means of some non-detectable alterings or falsifications, misappropriations of rights that they can generate (tax form, birth certificate, receipts, contracts, invoices, checks . . . ) whatever the sophistication brought to the elaboration of the original document.
E--Some documents have required high efforts to their author who is presently paid only by the diffusion of the original and not by the possible copies of these originals.
F--Some documents, or the global documents from which they are extracted, can't be easily copied by their owner, due to their nature (binding, clipping . . . ) or to their deterioration (incomplete document, partial diffusion).
G--For any computer-related document produced on a collective printer, the produced document that may be highly confidential can be consulted willingly or unwillingly by third persons between the instant of its production and the instant when it is recovered by its owner.
To all these problems related to the safety of diffusion and use of the documents, not very efficient or too awkward conventional solutions that are presently applied are:
A/B--These points are solved only by a harsh supervision (under lock and key) of the strategic documents of the company or by a limited access to the reproduction means. This is often ineffective, due to a bad estimation of the strategic importance of some documents and to the difficult discipline rarely applied for this protection.
C--The protection is ensured by a developed graphism, the use of specific media or technologies (metallic wire, magnetic ink or track, holograms . . . ) difficult to implement or costly. The complexity of these solutions limits their use and often only an expert can distinguish between true and false.
D--Today only the certified copies provide with a relative safety that can be absolute only by a written confirmation request to the emitting authority. This process is heavy and can often be implemented only exceptionally and when there is already a doubt.
E--Only the laws concerning the protection of the authors permit to prohibit such copies, but out of penal sanctions that are not easy to apply and that are not very dissuasive, nothing really impedes such infringements.
F--Today the user must "unbind" the document or make altered copies or else make a manual request to the author of the document when this one can be identified and when he has means for answering to this request; as a consequence the present limits.
G--The proliferation of personal printers with all the problems arising in terms of organization and maintenance and that can't prevent main structures from being provided with collective printers for more sophisticated works.
The method and devices for implementing this method permit to solve this problem for safety of production, diffusion and use of sensitive documents. Prior to the definition of the invention, it would be useful to define the different kinds of document that can be processed by the devices (these categories may overlap):
the first category of document concerns any free-diffusion document having neither confidential nature, nor juridical value, nor intrinsic value due to its aspect and not belonging to any of the following categories. This type of document is named as "conventional document" hereafter,
the second category concerns the documents of confidential nature, i.e. the contained informations of which must not be freely disclosed, this second category being named as "confidential document" hereafter,
the third category concerns documents certifying either transactions, or capabilities or rights; documents the authenticity of which is essential. In this category, it is possible to include the following elements: invoices, diplomas, receipts, contracts, law acts or administrative documents, tax report, checks, restaurant-checks, . . . This category is named as "authenticatable document" hereafter,
the fourth category concerns any document the matter of which results from some work and the diffusion of which justifies the payment of rights to its author. In this category, it is possible to include books, magazines. . . . This fourth category is named as "author's document" hereafter.
the fifth category concerns any document the identical copy (or approximately identical) of which may represent a damage for the emitter of the original due to a derived use of possible copies. Only the actual document has a value but not the informations it contains. In this category, it is possible to include the bank notes, the tickets and other documents with intrinsic value. This latter category is named as "valuable document" hereafter.
In order to gather all the categories of documents other than "conventional document", these categories will be gathered into a general category "sensitive document".
Furthermore, a distinction will be made hereafter between a paper document concerning a conventional document on a paper medium and an electronic document characterizing the electronic element that corresponds to the whole definitions under the form of electronic files of a document that may correspond after printing request to a paper document.
In order to describe the invention, it will be referred to the digitized form of a document: for a paper document, it means its decomposition into black or white elementary points or defined by a color attribute. This decomposition allows an electronic storage of the file and brings the opportunity of a logical processing.
The main feature of the invention consists in the following method based, on the one hand, on the definition of additional specific graphic elements on the document to be processed, and on the other hand, on the definition of the actual processing.
On the documents, the new elements are:
the marking,
the rules.
The "marking" is an element which permits to differentiate the "sensitive documents" from "conventional documents". This "marking" is achieved by a peculiar graphism (visible or not) on the whole document that does not alter the readability of the actual document but that must be detectable even on a reduced part of the document. This "marking" is present on any document considered as a "sensitive document" and consequently is missing from any "conventional document".
The rules are an element concerning all the "sensitive documents" and define the rules and restrictions of reproduction of the concerned document, this element is referred as "rules" hereafter. The reproduction rules and restrictions may require the knowledge of elements of referencing and identification of the presented document that are then integrated to the "rules". These "rules" permit associate to the document the indications concerning the reproduction opportunities as well as the actions that the processing device must achieve when a copy of the document is requested to it. This element is a complement to the "marking" (a document without "marking" has no "rules", and an element having a "marking" must detain the "rules"). The "rules" are encoded on the document by using a technique that alters at a minimum the readability of the actual document. If the "rules" enable the reproduction of the document but with an alteration of the original, the alteration guidelines are included in the "rules" by using a appropriate language (already existing or specifically defined for this use).
The techniques used for the definition of the "marking" and the "rules" must be compatible with the digitization of the document in view of a search and an extraction of these elements within the actual document.
The corresponding method includes the following steps when a document reproduction is requested:
a definition request of the reproduction work to carry out,
a presentation of the original paper document concerned by the reproduction request,
a digitization of the original document,
an analysis of the digitization result for detecting a possible "marking" of the document in order to determine the "conventional" or "sensitive" nature of the document; carrying out of the request when the presented document is a "conventional document",
If a document is identified as a "sensitive document" after the previous step, an additional analysis for searching and extracting the "rules". In the case of an anomaly, a rejection of the request with possibly safety actions.
If the document is identified as a "sensitive document" farther to the previous steps, authorization controls of the request with regards to the elements defined in the "rules" and to the elements characterizing the request and the requester; rejection of the request if this request is not authorized with possibly safety actions.
If the document is identified as a "sensitive document" and the request is authorized further to the previous steps, processing of the actions defined in the "rules" or deriving from them in combination with complementary elements provided by the requester,
Production of the requested reproduction according to the guidelines deriving from the interpretation of the "rules" if the presented document is a sensitive document and the reproduction is authorized. In the case of an authorized reproduction of a "sensitive document", the carrying out of actions provided in the "rules" or those deriving from said "rules" may have the effect of getting a different or altered copy compared to the original and equally may generate management actions linked to the achieved reproduction. The document produced from a "sensitive document"-type original is also a "sensitive document" that has own "marking" and "rules" (that may be different from those linked to the original).
For the implementation of the method, the following "markings" matching the above-cited definition are proposed in a non-limiting way (it is better as a way of normalization that only one among possible "markings" be chosen):
A first recommended "marking" consists in the superposition to the actual document of a fog of elementary points or signs.
Another recommended "marking" consists in a peculiar elementary-thickness pattern superposed to the actual document.
A third "marking" consists in framing any character within the document by an elementary-thickness filet.
For the implementation of the method, the "rules" that comprise several informations that can be characterized by strings of alphanumeric characters and consequently by using a conventional digital encoding (1 byte for one character) can be described by a succession of binary values. For the encoding of these values, the use of bar-codes is satisfactory. However for discretion reasons (the insertion of the "rules" must not damage the aesthetic of the document) and efficiency reasons (the decoding is made by analysis of the digitized document but not by scanning of the laser beam), the following encoding is proposed as a non-limiting way:
At predefined locations, several occurrences of the "rules" are inserted.
Each occurrence comprises a graphic heading and actual data,
The heading permits the identification of the character "rules" of the set heading and data and the definition of an origin and a direction for reading coded data,
The coded data are represented by a succession of regularly-spaced elementary-thickness bars, the presence or the absence of this bar corresponding to the value 0 or 1 of the corresponding position.
In order to ensure a larger dependence between the "rules" and the document on which they are inserted (i.e. in order to avoid a potential easy substitution of the "rules" of a document by those more permissive of another document), the encoded values could be modulated by statistical values linked to the document (number of characters of the page for example) so as that the decryption could establish a coherence diagnostic between the read "rules" and the corresponding document.
For the "marking" and for the "rules", an ink reflecting only in the infrared can be used for achieving their materialization: in this case, the digitization of the document will have to provide each elementary point of the document with an "infrared" attribute. This peculiar "marking" can be limited only to the "valuable documents": provided that any device technically able to produce a copy with a sufficient quality to be confounded with the original, could detect both the conventional "marking" and the peculiar "marking" (the other devices will produce, due to their technologic limitations, sufficiently altered copies not to be as a consequence considered as "sensitive documents").
For the implementation of this method to the local reproduction of "sensitive documents", the following device is defined. This device comprises the following functional modules: "user interface module", "digitization module", "analysis module", "control module", "creation module" and "printing module".
The user interface module can include existing features on the photocopier-type systems with the opportunity for the user to define his request and to be able to precisely identify himself (name, password, service . . . ) either by acquisition or by badge presentation.
The "digitization module" could be a conventional digitizer ("scanner") with if necessary an automation of paper flow in order to be able to digitize a set of documents in entrance. The digitizer provides a decomposition in black and white elementary points or with color attributes according to the case in order to permit an electronic operation of the presented document, if the "marking" and the "rules" use inks that reflect only in the infrared, the digitizer must be able to provide an infrared attribute at each elementary point of the document in surplus of the conventional digitization.
For the "analysis module", the "control module" and the "creation module", the functions are carried out by a computing entity (microprocessor or the like) with internal communication buses complying with the driving of the whole modules of the device. The analysis module includes algorithms adapted for the detection and the extraction of the "marking" and the "rules" from the digitized document. The "control module" carries out the control of the whole modules and their cohesion.
The "creation module" composes the digitized image of the document to be produced (when authorized) from the digitized image of the original document without its "marking" and its "rules" while respecting the modification guidelines included in the rules of the original. The document built this way comprises its own "marking" and its own "rules".
The "printing module" that permits to obtain the paper copy defined by the user request from corresponding electronic elements when it is authorized, could be implemented by the analogue module existing in the digital photocopiers or in the printers. If the "marking" and the "rules" use inks that reflect only in the infrared, the "printing module" will have to carry out the printing.
The set of such defined modules constitutes a functional entity named "document server" hereafter. The functional entity "document server" could be completed with new functional modules according to the following characteristics of the invention.
The device defined this way will be able to make the following actions when a user wishes to reproduce a "sensitive document" (identified as sensitive by the "marking")
Carrying out authorization controls deriving from the decrypting of the "rules" of the presented document in view of the user via the "user interface module",
Actuating safety systems (capture of the original, alarm . . . ) in the case of a non authorized reproduction of a "confidential document"-type document,
Accounting author's rights concerning the document in order to get a regular report of these rights by an authorized person or organization in the case of a reproduction of an "author's document"-type document,
Generating a modified copy versus the original by carrying out the modification guidelines of the document derived from the reproduction in view of the original; these guidelines derive from the interpretation of the rules, more peculiarly and in a non-limiting way for the "valuable document"-type documents.
For the implementation of the method in the case of a remote reproduction, the same device than above-cited can be used, provided that two new functional modules be included: a "communication module" and an "output management module". These two new modules belong to the functional entity "document server".
The "communication module" permits a dialogue and exchange of any electronic file required for the reproduction of documents, between two "document servers". Thus, a receiving "document server" carries out the reproduction request of an emitting "document server"; the two "document servers" altogether globally respect the above-described method according to the invention. The "communication module" may include the equivalent modules from telecopiers or computer stations connected to a computer network. At this level, any protocol ensuring the securing of transmitted data at a confidentiality level can be integrated.
The "output management module" is a computer module activated when the requested copy results from an external request (from another device) and that makes a retention on the document to be produced, freeing it only when the receiver has identified himself to the receiving "document server" producing the document.
In order to make the device not only reproducing "sensitive documents" locally or remotely but also producing the originals of "sensitive documents", said device keeps the functional entity "document server" identical in terms of components to the previous definition, with only adaptations in its operation. In parallel, a "driver" is added in every computer system provided for printing sensitive documents. This "driver" is a computer module that is integrated to the host computer system that is provided for sending to the "communication module" of the "document server" by using the communication capabilities of the computer system.
The actual document under digitized form derived from an application resident on this system,
The "rules" associated with the document or the elements permitting their reconstitution,
The actual characteristics (paper Format, Recto-Verso, Pages to be printed, numbers of exemplars Orientation . . . ) as well as the identifier of the emitter in relation to the receiver device when the document to produce is a "sensitive document",
The transmission of these informations permits the execution by the device of printing of an original of a sensitive document by using the same method than for the local reproduction from a remote reproduction request.
For implementing the method in the case of the production of originals of "authenticatable documents" and the production of authenticated copies from these originals, the device comprising the "document server" and the "driver" as previously defined includes two new functional modules: the "directory module" integrated to the functional entity "document server" and the "archiving server";
The "directory module" is an electronic module, it permits to make locally correspond electronic addresses (permitting on an electronic communication network the establishment of a communication session with the designed correspondent) with the identification of the emitting organization as can be defined in the rules. This "directory module" is updated by the holder of the "document server" (via a suitable dialogue at the level of the "user interface module" or by a computer link with the computer systems of the holder of the "document server") so as to accept to authenticate only documents from perfectly identified authorized organizations. This prevents from using falsified "rules" referencing fictive organizations; in this case, the device will not be able to authenticate the document because it will be impossible for the forger to establish a link between the device and this false organization.
The "archiving server" is a conventional computer system having sufficient storage, processing and communication characteristics. It mainly comprises two functional sub-modules: a "communication module" (of the archiving system) and an "archiving manager",:
the "communication module" (of the archiving server) allows the "archiving server" to communicate with any computer system having to produce originals of "authenticatable document" and with any "document server" having to produce an authenticated copy from an original of a "authenticatable" document,
the "archiving manager" carries out any required management and control on the "archiving server" for the production of an "authenticatable document" and for the production of an authenticated copy from an "authenticatable document".
Thus, when a computer system produces an authenticatable "sensitive document" on a "document server", the "driver" associated with the device simultaneously sends the same document under its electronic form accompanied with complementary elements defining the "rules" to the "archiving server".
When a user wishes to get an authenticated copy of an "authenticatable document" on a "document server", after the identification of the sensitive character of the document by means of the detection of the "marking" and the authorization control following the interpretation of the "rules", the "archiving server" linked to the document to be reproduced is searched in order that said "archiving server" send electronic elements required for the carrying out of the request. When the presented original features only an excerpt of the corresponding archived electronic original, the "archiving server" permits the requester to enlarge his request by sending to the "document server" all the required elements defining the global document. The "archiving server", in parallel with the carrying out of the request, makes any required additional authorization control or any management action associated with the delivering of the copy; it can also send guidelines that are complementary with the "rules" encoded in the presented original in view of the production of the copy (for example, in order to make appear in clear on the copy the copying character as well as the obtaining date of this copy). The "archiving server" also manages the royalties concerning the author's rights when required.
From an "authenticatable document", the obtaining of an electronic copy, or even the carrying out of an electronic transaction (for example, a check issued by an organization X and presented by a user Y generates under the control of the archiving system of X a transfer from the account of X to the account of Y) depending on the presented original can be better than the obtaining of a paper copy.
For implementing the method in the case of a production of an electronic copy or electronic transaction authenticated from an original of a "authenticatable document", the device comprising the "document server", the "driver" and the "archiving server" as previously defined includes the new functional module: "processing module":
the "processing module" is integrated on any electronic system having to receive the required authenticated electronic copy or transaction, it manages the reception of electronic elements from the "archiving server" following the request expressed at the level of the "document server" for producing on the host computer system the required element, the "document server" carries out all the analysis and control processing required for the processing of the "sensitive document".
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a flow-chart of the method,
FIGS. 2 to 4 feature the various examples of "markings" recommended according to the definition made in the method,
FIG. 5 is a representation of an occurrence of "rules" according to the recommendation made in the present invention,
FIG. 6 is an example of implantation of the various occurrences of "rules" in a document using the first recommended type of "marking",
FIG. 7 illustrates the adaptation made on an encoding of "rules" according to the recommendation for a pattern-type "marking",
FIG. 8 illustrates the organic composition and the operation of the device for implementing the method in the case of a local reproduction,
FIG. 9 illustrates the organic composition and the operation of the device for implementing the method in the case of a remote reproduction,
FIG. 10 illustrates the organic composition and the operation of the device for implementing the method in the case of a printing from a computer system,
FIG. 11 illustrates the organic composition and the operation of the device for implementing the method in the case of the production of an authenticatable original, and
FIG. 12 illustrates the organic composition and the operation of the device for implementing the method in the case of the production of an authenticated paper copy, of an authenticated electronic copy or of an authenticated electronic transaction from an authenticatable original.
DETAILED DESCRIPTION
A detailed description of the invention follows, with reference to these drawings and figures:
The method links up the following steps:
Formulation of the request (101)
The method is initialized by a reproduction request that mentions which work has to be done on the original that will be presented. This definition allows to define, among others, the paper and the output format, the number of copies, the local or remote nature of the copy. If the presented document features only a part of a more global "authenticatable document", the requester indicates at this level only his wish to get an authenticated copy, the whole request being defined in this case in the request authorization control step (cf. 108).
Presentation of the paper original (102)
Further to the request, the document to be duplicated is presented. The page or the pages to be reproduced are therefore presented in the desired order. However, in the method, each page is an integral element that is processed in a distinct way, the following steps can generate different actions according to each of the presented pages. The presented document may feature only an excerpt of a more global document if this document is an authenticatable document-type document and if the requester desires to get a copy of the whole or of a part of this global document independently of the presented excerpt.
Digitization of the original (103)
In order to be processed by a logic algorithm, the paper document that is a material element is transformed into a logic element. To this aim, the digitization modelizes each presented page into a matrix of points. An attribute is associated with each point; white, black, color, infrared or other according to the technology used to materialize the information on the document.
"Marking" search (104)
A search is carried out on the logic image of each page (i.e. after digitization), for detecting the presence of a "marking". As the "marking" is a graphic element that is predetermined and normalized in the present invention, a detection algorithm can be defined according to the selected "marking". The algorithm must take into account an error margin corresponding to the imperfection of the printing and of the digitization. The result of this step is a logic value: YES if a "marking" is detected on the processed logic page and NO when no "marking" is detected on the logic page. This value conditions the following steps of the processing.
Processing in case of non-detection of a "marking" (105)
If no "marking" has been detected on the processed page, the initial request is made for this page since said page constitutes a "conventional document". However, the global request will only be integrally taken into account if all the presented pages for a same request are "conventional documents".
Processing in case of positive detection of a "marking": Search of the "rules" and coherence control (106)
When a "marking" is present, the document is considered as a "sensitive document". In this case, reproduction constraints are defined and are inserted under the form of "rules" into the document. The aim of the present step is to detect said rules and to check their validity, as well as to extract them. The rules being encoded under the form of a predetermined and normalized graphic binary coding, an algorithm of detection and extraction can be defined, including the controls of binary validity if it is required in the encoding. If the encoding is provided for several occurrences in the page, the coherence of the decrypting of the various occurrences is carried out. If the encoding is modulated by statistical values related to the content of the actual document, these statistical values are computed again in order to validate the values of the extracted "rules". The result of this step is a logic value: YES if valid "rules" are detected in the processed page and NO if the document does not include "rules" and if the document includes invalid "rules". In parallel with this value. a more precise diagnostic can be provided in view of suitable processing.
Processing in case of presence of "markings" and of absence of valid "rules (107). This case being considered as abnormal (the method defines the complementary presence of a "marking" and "rules"), the initial request concerning the processed page is rejected. Furthermore, safety actions can be generated: alarm, capture of the original, memorizing of the request and his author. . . .
Processing in the case of the presence of a "marking" and the presence of valid "rules" (108). The "rules" are interpreted in order to verify that the expressed request is authorized and additional controls towards the requester are made (the authorization may depend on the characteristics of the requester or on the request itself: for example, the local reproduction may be authorized but not the remote reproduction). If the expressed request concerns the obtaining of an authenticated copy, independently from the authorization controls that are systematically made for any sensitive document, an additional control is made in order to check that the presented document is effectively an "authenticatable document"; in this case, the elements characterizing the electronic original of the global document corresponding to the presented "authenticatable document" are searched in order to allow the requester to complete if necessary the definition of his request, or even to leave it. At the end of these controls, a logical value is updated: NO if the expressed request is not authorized or not maintained and YES if the request is authorized and maintained (the control step may make appear a royalty that the requester may accept or refuse).
Processing in the case of a non authorized or non maintained request (107)
Like in the case of the presence of a "marking" and the absence of valid "rules", the request is rejected and there is possibly activation of safety systems if the initial request corresponds to a violation attempt of a "confidential document"-type document by a non authorized person.
Processing in the case of an authorized request on a "sensitive document" (109)
The digitized image of the document to be produced is generated according to guidelines deriving from the nature of the request and of the operation of the "rules", further including modifications towards the original (masking, overprinting, color suppression, graphism modification . . . ); a consequence of that can be the building of the image of the actual copy not versus the digitized image derived from the presented document but from an electronic original linked to the presented document when an authenticated copy is required. These guidelines could have been encoded according to the rules by elementary orders expressed in a suitable language. The image made this way includes a proper "marking" independent from the "marking" of the original document and proper "rules" that could be different from the initial "rules" (in particular, the reproduction rights of the obtained copy could be different from those of the original). In addition to these direct actions on the produced document, additional actions could be made concerning the accounting of author's rights (according to informations contained in the "rules") or globally on the production management of sensitive documents (date, hour, references of the produced documents, identity of the requesters . . . ) for consultation by an appropriate manager.
Carrying out of the request (110)
The document under its digitized form is transformed into a paper document.
For the implementation of this method, a predefined and normalized "marking" has to be established, for that, various typical "markings" are recommended by the invention. Schemes 2 to 4 give a representation of said "markings".
In the following definitions, whenever an elementary thickness is indicated, it means that the thinnest thickness able to be printed and then to be detected after a digitization is chosen (possibly modulated by an algorithm able to partially compensate these limitations).
The first recommended "marking" concerns a typical document (201) comprising several coherent parts that are paragraphs or graphics (in the mentioned example, this document has two coherent parts that are 2 paragraphs (202) and (203)). Out of the coherent parts, the document has two main margins (204) and margins separating the coherent parts (205). Only in the coherent parts outside the characters (207) or graphics constituting the document, isolated points (206) are disposed within the whole coherent parts without being superposed to printing components of the texts and graphics according to pre-established density norms. Unlike the representation of scheme 2, the points are thin enough not to alter the visibility of the document (here, they are more imposing for illustrating aims, moreover the used density is not representative of the one that will be used as a normalization); the points can be advantageously replaced by any more complex symbol (with an elementary thickness in order not to be harmful to the readability of the document).
The second recommended "marking" consists, for a typical document (210) including a set of text and graphic elements (211) in superposing a pattern. In the present case the pattern comprises parallel oblique bars (212) extending from one edge of the document to the other alone a predefined spacing with an elementary thickness in order not to be harmful to the readability of the document.
The third recommended "marking" consists for a typical document (non represented), in framing each character (221) by a rectangular filet (222) with an elementary thickness.
The recommended "rules" are encoded on a document under the form of several identical occurrences. Each occurrence comprises a heading (231) and a data part (232). The heading (231) permits the identification of an occurrence and the determination of its reading direction: to this aim, the heading in the proposed recommendation comprises a sign "+" (233) with an elementary thickness followed by an orientation bar (234) with an elementary thickness. This heading (231) permits the identification and the decryption of the data part (232) for which at each predefined spacing an elementary-thickness bar provides with a binary value 0 or 1 by its presence (235) or its absence (236). The assembling of these binary values permits the reconstitution of the interpretable values of the "rules".
For a same document, several occurrences of "rules" are inserted, thus in a typical document (241) using for example a fog-of-points-type "marking", it is possible to define main margins framing the document and intermediate margins separating each coherent part of the document (242): paragraphs, graphics. . . . An occurrence of "rules" is inserted in each main margin, at each end and at the middle (243) in the limit of the available place. Similarly, an occurrence is inserted at each end and at the middle of each intermediate margin (244) in the limit of the available place.
If the used "marking" is a pattern-type "marking", the graphism of the "rules" is adapted for being inserted between two pattern elements (251). The "rules" still consist in a heading (252) and a data part (253), the signs and bars constituting the encoding of these elements ((254)(255)(256) and (257)) are adapted for maintaining a parallelism between themselves, when it is justified, and with the pattern elements (251).
The device proposed for the implementation of the method to its use for a local reproduction is materialized by a "document server" (1) that mainly includes the following functional modules: a "user interface module" (11), a "digitization module" (12), a "control module" (15), an "analysis module" (6), a "creation module" (17) and a "printing module" (14). This "document server" (1) permits a user (31) to request a paper copy document (43) from a paper original document (41). For that, the user (31) enters his original (41) into the "digitization module" (12) and defines his copy work to the "user interface module" (11). Following this request. the "user interface module" (11) sends it to the "control module" (15).
This module (15) controls the "digitization module" (12) to make it providing a digitized document (42) from the paper original (41), thus exploitable by an electronic-type entity. When the initial digitized document (42) image of the presented document (41) is obtained the "control module" then requests to the analysis module" (16). This module (16) extracts from the initial digitized document (42) the actual basis document (44), i.e. excluding any "marking" or any element corresponding to the "rules". In parallel with this result the analysis module determines the presence or not of a "marking" and if this detection is positive, searches the "rules" and reads them to form from them a exploitable electronic file (45); this module (16) validates at this level the concordance between the read "rules" and the presented document (41), a diagnostic concerning this concordance is integrated to the exploitable "rules" (45). When no "marking" is detected, that means that the original (41) is a "conventional document"-type document; the "control module" (15) then requests to the "creation module" (17) to make it directly fabricating the final digitized document (47) from the basis digitized document (44). Then, the "control module" (15) requests to the "creation module" (17) for the direct obtaining of the requested copy (43) from the final digitized document (47). If a "marking" has been detected and if no "rule" could have been read or if the different occurrences of the read "rules" are not coherent between themselves or of the read "rules" do not correspond to the presented document (41), the "control module" (15) refuses to achieve the copy by destroying the resulting files from the analysis (42) and (45); and, possibly, alerts the user by requesting to the "user interface module" (11) or initiates a safety action: alarm, capture of the original. . . . If a "marking" has been detected and coherent "rules" have been read, the control module processes these "rules" and achieves the corresponding processes. If the copy (43) must be produced and the original is a "sensitive document", the "control module" (15) builds the new "rules" (46) associated with the document to be produced (43) and passes the hand to the "creation module" (17). This module (17) builds from the basis digitized document (44) and from the new "rules" (46) an image under the form of a digitized document (47) of the document to be produced (43) including the actual document, the "marking " and the possible "rules" linked to this document; then the "printing module" builds the document to be produced (43) from this electronic modeling (47).
For the first recommended "marking" (fog of points), the "marking" search can be done in the following manner:
Searching coherent zones of the presented document, i.e. as a way of example the zones (202) and (203). For that, eliminating any white rectangular part of the document that has a width in elementary points ("dots") larger than a predefined width and similarly for the height (a part is considered as white when the density of present isolated points is less than a predetermined value), it results an elimination of the margins (204) and (205) in the case of the example of scheme 2. Any graphic element potentially belonging to an occurrence of "rules" (sign + or bar, within the recommendation) is considered as a "white part" within the present search.
From the resulting zone of the previous step, for example in the case of the example the parts (202) and (203), the potential surface is counted in elementary printing points of this whole zone. This gives a number NDOT. Any printing element characterized by the juxtaposition of several printing elementary points is searched in this zone; this is for example the case of a character, i.e. in the example of scheme 3, the characters equivalent to (207). The global surface in dots of these whole elements is counted, to get NUTIL. A new search permits the counting of all the printing isolated elementary points, to get NMARQ.
From the previous results, the marking density is computed by the formula D=NMARQ/(NDOT-NUTIL); this density is compared to the normalized density characterizing the "marking". The result of this comparison will be used as a diagnostic to define the sensitive or conventional nature of the presented document.
For the second recommended "marking" (pattern), a search is carried out on the whole document(210) to detect all the occurrences of bits of pattern (212) (in the example: a bit of pattern could be defined as an oblique bar with an elementary thickness and a length of at least 1 cm for example). According to the number of such found elements and their geographic distribution within the page, a diagnostic of normalized pattern presence can be done and consequently a diagnostic concerning the nature of "sensitive document" or "conventional document" of the presented page can be carried out.
For the third recommended "marking" (filet framing), a search is carried out on the whole page to identify all the characters (221) composing it. For each identified character, there is a checking whether said character has a framing by an elementary filet (222). If a document has more than a predetermined number of characters in the page having such a framing, the document is considered as a "sensitive document" and as a "conventional document" on the contrary.
If the document is considered as a "sensitive document" (further to the detection of a "marking"), any occurrence of "rule" is searched. For that, there is a search of the graphic identifier of "rules" (233) or (254) validated by the orientation bar (234) or (255). After detection of the heading (231) or (252) defined this way, the data (232) or (253) are searched. For that, at each elementary spacing, there is a detecting of the presence (235)/(255) or the absence (236)/(257) of bar. The complete detection permits to decrypt the encoding of the occurrence and possibly to validate it. If encoding integrity control values are defined (control binary total, for example), this validity is controlled. If several occurrences of "rules" are detected, their coherence is validated. If the encoded values are modulated by statistical values linked to the presented document, these statistical values are computed again to check the concordance of the read "rules" with the presented document.
If the document can be reproduced with constraint, the "control module" links up the processing resulting from the interpretation of the "rules" (45) of the document (41); said processing will include, as the case may be:
control requesting to the "user interface module" (11) of an authorization of the user (31) towards the access defined in the "rules",
accounting the author's rights if the document is a "author's document"-type document,
if the reproduction is authorized, fabricating from the "initial rules" (45) "final rules" (46) that are the "rules" associated with the document to be produced (43),
requesting to the "creation module" (17) with possible transmission of guidelines for modification of the basis digitized document; these guidelines correspond to the interpretation of the "rules" of the initial document (41).
The "control module" (15) requests to the "printing module" (14) when the "creation module" (17) has completed the fabrication of the "final digitized document" (47).
In all the cases where the reproduction is not authorized (further to a diagnostic of the "analysis module" or after failed request of identification of the user (31) to the "user interface module" (11)), the "control module" possibly actuates the safety systems (alarm, capture of the original . . . ) and destroys in the device any internal element built from the initial document (41): "initial digitized document" (42), "initial rules" (45) and "basis digitized document" (44).
The "creation module" (17) builds the "final digitized document" (47) directly from the "basis digitized document" when the document to be reproduced (41) is a "conventional document"-type document. In the other cases, the final digitized document (47) is built from the "basis digitized document" (44), the "final rules" (46) and the possible modification guidelines transmitted by the "control module" (15); the "creation module" (17) introduces a new "marking" to these elements.
The device proposed for the implementation of the method to its use for a remote reproduction is materialized by a "document server" (1) that further includes modules used for the remote reproduction: the "communication module" (18) and the "output management module" (19).
When a user (31) requests to his "document server" (1) to transmit a document (41) to his correspondent via the remote "document server" (2) of this correspondent (32), said user (31) introduces his document (41) on his "document server" (1) as for a local copy; the two "document servers" (1) and (2) of the user (31) and the correspondent (32) are identical. The driving of the modules is achieved by the "control module" (15) of the concerned "document server". After the expression of the request via the "user interface module" (11) of the emitting "document server" (1), the "digitization module" (12) of the emitter (1) produces a document under digitized form (42). This document (42) is analyzed by the "analysis module" (16) of the emitter (1) according to the same principle than for obtaining a local copy. This module (16) on the emitter (1) produces, like in the case of the local operation, the basis digitized document (44) (excluding any "marking" and any "rule"), and the "initial rules" (45) linked to the original document (41). At this level, the "control module" achieves the same tasks of control, counting, fabrication of final "rules" (46), or fabrication of copy modification guidelines deriving from the operation of the initial "rules" (44) while checking that the document (41) can be remotely reproduced (according to informations contained in the "rules") and then carries out a request to the user (31) via the "user interface module" (11) of the emitting "document server" (1) for obtaining the identification of the receiving "document server" (2) and the identifier of the correspondent (32) towards the receiver(2) or any equivalent information. The identification of the "document server" (2) is either a phone number in case of a telephone-type link, or a computer network address in the case of the use of a computer link. The identifier of the correspondent (32) is the same than the one that allows a user to identify himself to the "document server" in the case of a local copy; this identifier, in the case of the chosen example, must be accompanied by a password (this is not necessary if the correspondent has other means of safe identification: magnetic badge or equivalent). If the remote copy is authorized, after providing by the user (31) of the identification of the receiver (2) and the identification of the correspondent (32) towards the receiver(2), the control module requests to the "communication module" (18) of the emitter (1) for transmitting to the receiver (2) the elements permitting the remote copy. The "communication module" (18) of the emitter (1) establishes a communication session with the communication Module (18) of the receiver (2) by using, depending on the case, either a telephone network, or a computer network (71). The basis digitized document (44), the final "rules" (45) and possibly the guidelines of modification of the copy versus the original, are transmitted through this communication; this is completed by the identifier of the correspondent (32) towards the receiver (2). Further to this reception, the "control module" (15) of the receiver (2) requests to the "creation module" (17) of the receiver (2) for building on the receiver (2) the final digitized document" (47) from the "basis digitized document" (44) on the receiver (2) and the "final rules" (46) on the receiver (2) and possibly the guidelines of modification of the copy versus the original. The "final digitized document" (47) is then processed by the "output management module" (19) of the receiver (2) that stores it on a specific queue (non represented on the scheme) by linking to it the identifier of the correspondent (32) designed by the emitter user (31). For obtaining the desired copy, the correspondent (32) must identify himself to the receiver (2) via the "user interface module" (11) of the receiver (2) by seizing his identifier and his password (or depending on the case, by a magnetic badge or the like). Further to this identification, all the documents received on the receiving "document server" (2) and linked to the identified correspondent (32) are listed. Then the correspondent (32) frees the document(s) that he wishes to obtain, in this case, the "output management module" (14) of the receiver sends back the corresponding document(s) of his queue to the "printing module" (14) of the receiver (2) in order to obtain the desired copy(ies) (43). If management tasks are necessary concerning the provided copies of "sensitive documents", said tasks are done only at the moment of effective delivery of the document(s) (43).
The device proposed for the implementation of the method in its use for carrying out a printing from a computer system is materialized by a "document server" (1) that includes the same functional components than for the remote reproduction, and a "driver" (82) present on any computer system having to produce "sensitive documents". The computer user (33) conceives a document by means of the use of an application (81) resident on a computer system (72). The result of this conception is the image of the document under a digitized form (48). In fact, the result will be the image of the document under a descriptive form by the use of primitives of a page description language: in this case, an interpreting sub-module must be introduced either at the level of the computer system (72), or at the level of the "documents server" (1). For simplification aims, scheme 9 assumes the simplification hypothesis that the result of the application is a document under a digitized form. To send the document on the "document server" (1), a driver (82) is installed on the computer system (72). This driver permits to gather the elements required for establishing "rules" (49) associated with the document to be produced, either by an initial parametering, or by a dialogue with the user (33), or by a search of elements stored on the system (72), or by combination of these means. These "rules" are identical to those defined for a document normally derived from the device, only the encoded values being adapted to this new type of source. The set document (48) + "rules" (49) + identifier of the user (33) is transmitted to the "document server" (1) via a computer network (71) by use of the communication modules (83) then (18) of the two concerned systems. After reception of these elements ((48)(49) and identifier) on the "document server" (1), the "control module" (15) requests to the "creation module" (17) that produces the final document under a digitized form (47) from the received document (44) and the received "rules" (46). This document (47) is processed by the "output management module" (19) that stores it on a specific queue(non represented on the scheme) while linking to it the identifier of the user (33). The printing is freed only in presence of the user (33). To obtain the desired copy, the user (33) must identify himself to the "document server" (1) via the "user interface module" (11) by seizing his identifier and his password (or depending on the case, by a magnetic badge or the like). Further to this identification, all the documents received on the "document server" (1) and linked to the identified user (33) are listed. Then the user (33) frees the document(s) that he wishes to get, in this case, the "output management module" (19) sends back the documents(s) corresponding to its queue to the "printing module" (14) to obtain the desired printing(s) (43). The control of identifier/password can be done by request to the computer system (72). If management tasks are required concerning the provided printings of "sensitive documents", said tasks are done only at the moment of the effective delivery of the document(s) (43).
The proposed device for the implementation of the method to its use in the production of an original of a "authenticatable document" for carrying out a printing from a computer system, and, in the production of an authenticated paper copy from an original of a "authenticatable document", comprises a "document server" ((1) or (3)), a "driver" (82) present on any computer system having to produce "sensitive documents" and an "archiving server" (73). This latter (73) mainly includes a "communication module" (84) and an "archiving manager" (85). The "document server" (1) further includes, besides the previously defined functional modules, a "directory module" (20). The operation of this device is as follows:
When an entity desires to produce "authenticatable documents" (92), said entity defines on its computer system (72) via the application manager (34) the documents to be produced (48) and, according to the invention, the elements permitting a definition of the "rules" (49) of these documents. The document to be produced is directly built by an application (81). The rules are produced by a driver (82) according to the same operation than previously. When the document is ready to be produced, it is sent via a computer network (71) to the "document server" (1) for printing and to an "archiving server" (73) that stores the electronic image of the document (91) via a "archiving manager" (85). This manager (85) must be able to find every document from elements contained in the "rules", it also possibly carries out every access or memorizing management of the provided copies. The transmission is done from the computer system (72) via its respective communication module (83) to the "document server" (1) and the "archiving server" (73) via their respective communication module (18), (83) and (84). On the "document server" (1), the final document (92) is produced like in the previous characteristics via the possible control of a production manager (35). The produced document (92) is transmitted to his addressee (36) via the conventional transmission means by mail and the conventional means of circulation of paper documents. This addressee may be either the direct addressee addressed by the emitter (34) or an external organization to which this document will have been transmitted by the initial addressee of said document (for obtaining of any right). When the addressee (36) identified this way desires an authenticated copy of this document (92), he presents said document to his "document server" (3) while requiring to the user interface (11) an authenticated copy but not a conventional copy (However, the possibility of obtaining an authenticated copy does not prevent the user from requiring a conventional copy without authentication from an authenticatable original). The user may also present only an excerpt of the authenticatable original document in view of obtaining a copy of all or a part of the global document, in this case, he expresses in his request only the wish to obtain an authenticated copy while reserving the precise definition of the request when he will have complementary elements on the global document. Then the document (92) is digitized by the "digitization module" (12) of his "document server" (3) to get a digitized image (42) of this document (92). The analysis module (16), after detection of the marking, analyses the "rules" according to the previously defined process. From the result of this analysis, the "rules" are transcript under an exploitable form (45) without obtaining an actual image of the document (43). The "control module" (15) makes a request to the "directory module" (20) in order to obtain the electronic address of the "archiving server" (73) associated with the computer system (72) having produced the initial document. In the case of a failure for this request, the operation is stopped with a corresponding message at the level of the user interface (11) in order to make the emitting organization being registered on the device by the authorized person. When the "directory module" (20) sends back the electronic address, the "control module" (15) sends said address accompanied by suitable references of the document to the "communication module" (18) in order to get an authenticated copy of the document. If the presented document is only an excerpt of the global document from which the user wants to more precisely define the desired copy (the excerpt of the copied document may diverge from the presented excerpt), the "archiving server" (73) sends back in a first time all the elements necessary to the document server (3) to permit the user to complete his copy request (detailed summary, reproduction cost for author's right . . . ). When the request is definitely expressed, the archiving server (73) searches via its manager (85) the electronic image (91) of the corresponding document (92) or defined from this latter. If the production of the required copy is associated with the payment of author's rights, the corresponding management is achieved by the "archiving manager" (85) of the "archiving server" (73). The communication is done via a computer network (71) by use of the respective "communication modules" (18) and (84). The "document server" (3) receives the electronic image of the document (91), allowing said "document server" to store both the digitized image of the actual document (46) and the "associated rules" (44) possibly adapted to the nature of copy of the document to be produced. Then the "creation module" (17) produces the digitized document under is final form (47) from the digitized image of the document (46) and the "final rules" (44). The authenticated copy (93) is produced from this element (47) by the "printing module" (14) via possibly the "output management module" (14).
The proposed device for the implementation of the method in the production of an authenticated electronic copy or the carrying out of an authenticated electronic transaction (i.e. under the control of the emitter of the document used for the transaction) from an original of an "authenticatable document" (92) comprises a "document server" (3), an "archiving server" (73) and a "processing module" (87) on any computer system having to receive the electronic copy or register the electronic transaction. The "document server" (3) and the "archiving server" (73) are identical to their previous definition, the "driver" (82) is not used in the present example.
The user (36) can request to obtain from an "authenticatable document" (92) under paper form, an electronic authenticated copy (94) or even an electronic transaction (95) associated with the presented document. The process is identical to the obtaining of an authenticated paper copy, but in this case, the "document server" (3), after analyzing the document (92) and obtaining the corresponding "rules" (42) as previously, requests to the "communication module" (18) after a request to the "directory module" (20) in order to have the concerned "archiving server" (73) directly sending the electronic image (91) of the presented document (92) to the computer system (74) indicated by the user (36). The transfer from the "archiving system" (73) to the receiving computer system (74) is done by the use of a computer network (71) via the use of the respective communication modules (84) and (86). The "archiving manager" (85) manages for the emitter of the original document the produced copies (94) or the generated transactions (95). A "processing module" (87) present on any receiving computer system (74) permits the storage and management in said system of the authenticated electronic copy (94) and the generation of elements (95) corresponding to the generated transaction (possibly) from the presented original (92).
The present invention can be used, according to its characteristics, within a same entity to guarantee a secured flow of the paper documents. A company, being equipped with the described devices, to the exclusion of any other document production or reproduction apparatus, is ensured that, within said company, no sensitive document will be printed in view of a non-authorized third person. In the same way, it will not be possible to locally reproduce or fax the document within the entity. The hacking of "sensitive documents" then involves a substitution of the document, which compels the hacker to take risks and leave marks of his hacking. If the invention becomes a norm for document-production or reproduction, it will permit to avoid the identical copy of valuable documents (bank note, ticket . . . ) and to ensure to the producers of documents a remuneration for every diffusion or copy of their works.
For every company brought to print documents opening rights (administrative, accounting documents, or documents associated with transactions), and for the companies registering the corresponding rights, using the device at the emission permits the use of an ordinary paper to the exclusion of any complex technology, while spoiling any falsification attempt since said falsification is ineffective on the generated transaction. Thus, it is for example possible to transform an emitted check into a transfer if the banks are equipped with an adapted device, to collect the restaurant-tickets, to process the additional reimbursements from the mutual funds in relation to the social security statements, to register, for the accountants or tax controllers, pay slips, invoices or any accounting document. For imposing documents, stapled or bound, the user can obtain an entire copy without breaking the presented document, just by presenting one page of the document (if authorized by the emitter). The emitter can keep an entire control of the documents that he produces, as well as of the reproductions or transactions obtained from these documents, or even perceive author's rights on any copy produced from the emitted original. | A method and device for securely duplicating sensitive documents. A marking element is entered on the original document to identify its confidential nature, as well as an encoded rules elements which defines duplication restrictions of the document. For each duplication request (101) for a sensitive document (102), the document is digitized (103) to determine the presence of a marking element (104) and to find the duplication restrictions, i.e., the encoded rules elements (106). Duplication may be performed (110) depending on the restrictions defined in the rules elements (106) and after an authorization check (108). A duplication may be obtained by requesting the computerized original of the document from the document issuer. In addition to the selective control of reproduction of documents the method and device is particularly suitable for preventing the duplication of documents for fraudulent purposes, multiple duplication of selected documents, and for copyright administration. It enables the issuer to retain control over the use of sensitive documents without fear of forgery. | 7 |
This invention relates to apparatus for the recovery of gold and other heavy minerals contained in dry alluvial and eluvial mining deposits. In particular, the invention is directed to an air concentrator for separating gold and other heavy minerals from such deposits.
BACKGROUND OF THE INVENTION
Most mining operations on alluvial or placer type deposits use "wet" gravity separation technology. That is, particles of gold and other heavy metals are separated from lighter weight dust and dirt by using a current of water. Although wet plant technology is usually sufficiently efficient to render mining operations profitable, it requires a large supply of water and also generates a large amount of debris. Consequently, wet gravity separators cannot be used in dry areas. Furthermore, dams are often required to be built to contain the environmentally hazardous slimes created by dirty water, adding to the cost of production. For environmental reasons, the use of large-scale wet separation plants is restricted or even prohibited in some countries.
To overcome such problems, air separators or concentrators, sometimes called "dry blowers", have been used for waterless recovery of gold and other heavy minerals from dry placer deposits. There are several categories of air concentrators or dry blowers, but most involve passing air through the deposit as it is conveyed along the concentrator to thereby separate heavy particles from lighter material. Apparatus such as bellows, fans and compressors are typically used to vary air flow through the deposit being processed, while vibrating feed devices, angled shaking tables and screens, gravity bypass methods, air tunnel devices and perforating moving belts are used to convey the deposit through the concentrator. Examples of known air concentrators or separators can be found in U.S. Pat. Nos. 2,752,041; 3,105,040; 3,080,056; 3,108,950; 3,207,306; 3,367,502; 4,294,693; 4,615,797; 4,642,180 and Australian patent application no. 14534/83.
Many concentrators, such as those described in U.S. Pat. Nos. 2,752,041; 4,615,797 and 4,642,180, are limited to small scale batch operations and are of limited application. Others may be suited to continuous or larger scale operations, but are invariably of expensive and complex construction with many moving parts, and generally require vibratory mechanisms to achieve high throughput of deposit. Such concentrators are not easily transported. As a result of these disadvantages, the known air concentrators have failed to find widespread user acceptance.
A common design feature of known air concentrators is that the deposit is processed as it passes along a generally linear path in single direction, e.g. down an inclined riffle board or longitudinally along a table. Consequently, known concentrators are generally of elongated configuration, and their throughput is limited by their maximum dimension.
Perhaps the most significant disadvantage of most known air concentrators or dry blowers is their low efficiency, i.e. poor concentration rates and relatively low recovery rates. Since, for any given deposit, the average grade of ore is generally constant, and as the price of gold and other minerals are fixed by the market, the only remaining variable which will determine whether a particular deposit is viable is production cost which, in turn, is directly dependant upon efficiency. Many deposits therefore, are not viable with known air separation plants of low efficiency.
It is an object of the present invention to overcome at least some of the disadvantages of prior art air separation plants by providing a relatively low cost, high volume, environmentally compatible, efficient air concentrator.
SUMMARY OF THE INVENTION
In one broad form, the present invention provides apparatus for dry separation of heavier materials from a mixture of particulate materials of different densities, comprising:
a housing having a screen thereon;
means for moving the mixture of materials across at least a portion of the screen; and
means for creating a flow of air from beneath the screen through the mixture so as to at least partially fluidize the mixture of materials thereby enabling heavier materials to settle to the bottom of the mixture by gravitational stratification and pass through the screen if less than the size of the screen apertures;
characterized in that the housing comprises a plurality of open-topped chambers which are arranged in a ring-like configuration subjacent the screen, and which in use, are sequentially supplied with air under pressure on a cyclical basis
whereby the portions of the screen above the respective chambers are pulsed with air flow successively and cyclically.
The apparatus is suitably used as an air concentrator or separator for recovery of gold and/or other heavy minerals from dry placer deposits and the like.
In the preferred embodiment, the housing is cylindrical in shape and is divided by radial walls into segments which form the chambers. Air under pressure is directed to each chamber successively by a rotary valve formed by a cylindrical or tubular casing located in the centre of the housing with the ring of chambers. The rotary valve has a vent at a predetermined circumferential location on the casing, and the bottom of the casing communicates with the source of pressurized air, typically a fan unit. The vent communicates with the inner opening of each compartment when it is aligned with said opening, otherwise the inner opening is effectively sealed by the cylindrical wall of the rotary valve casing. As the rotary valve rotates, pressurized air from the fan unit is directed through the vent to the chambers sequentially and cyclically. This design is very compact and economic as ducting is minimized and all space in the housing is utilised. In addition, the only principal moving part is the rotary valve, and the flow of air from the fan unit is continuous.
Each chamber is suitably provided with sloping bottom and/or sides so that heavy minerals falling therein are gravity fed to a spigot at the bottom of each chamber. Material passing through the spigots may be collected in any suitable manner. The spigots are of sufficient diameter to allow smooth flow of material therethrough yet small enough to not significantly reduce the air pressure in each chamber when pressurized via the rotary valve.
The screen is typically formed by an annular wedge wire screen which rests on the radial chamber walls of the cylindrical housing. A number of rings are provided on the screen to form annular beds in which particulate materials such as gravel etc. collect to form the screen beds. As each chamber is pressurized by the rotary valve, a puff or pulse of air flows upwardly through the beds over that chamber causing lighter material to lift while allowing heavier minerals such as gold to filter or percolate down through the fluidized bed and screen and into the chamber for collection through its spigot.
The moving means preferably comprises a wiper bar assembly located above the screen beds and having a plurality of off-centre radial arms connected to a central hub member. The mixture of materials is initially fed onto the hub member from where it falls onto an annular apron around the hub. As the hub member rotates, the wiper arms sweep around the top of the screen to spread the deposits falling onto the apron and maintain appropriate air bed environment. More particularly, the wiper bar assembly includes inner wiper arms which convey the materials from the apron to outer wiper arms which, in turn, spread the materials over the screen in a generally spiral trajectory. As the lighter material is lifted by the air pulses, it is bladed outwardly by the wiper arms, while the heavier materials settle down through the screen beds. As the particulate material mixture spreads radially, its rate of travel drops as it spreads over a larger area, thereby allowing a longer time for the heavier minerals to drop out and filter through the screen beds. The tailings are spread to the outside of the screen. Typically, a tailings trough is provided around the screen to collect the tailings for disposal.
The wiper bars are mounted to the hub member and the assembly is rotated by a suitable drive unit located within the hub member.
The wiper bar assembly is preferably mounted at its outer ends on rollers adjustably mounted on the outside of the cylindrical housing. The height of the wiper bars are adjusted to ensure correct height above the screen beds and to correctly condition the deposits material for maximum interaction with the fluidized screen bed.
In order that the invention may be more fully understood and put into practice, a preferred embodiment thereof will now be described with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view of the air concentrator of the preferred embodiment illustrating its assembly;
FIG. 2 is a part-sectional elevation of the concentrator of FIG. 1;
FIG. 3 is a schematic sectional plan view of the module and rotor of the concentrator of FIG. 1;
FIG. 4 is a schematic elevation of part of the module of FIG. 2;
FIG. 5 is a part-sectional elevation of the rotor of the concentrator of FIG. 1;
FIG. 6 is a sectional plan of the rotor of FIG. 2 along A--A;
FIG. 7 is a plan of the screen of the concentrator FIG. 1;
FIG. 8 is a sectional view of part of the screen of FIG. 7 along B--B;
FIG. 9 is a half-plan of the wiper bar assembly of the concentrator of FIG. 1;
FIG. 10 is a sectional elevation of the wiper bar module of FIG. 9 along C--C; and
FIG. 11 is a flow chart for the operation of the concentrator of FIG. 1.
DESCRIPTION OF PREFERRED EMBODIMENT
In its preferred embodiment, the air concentrator of this invention is a gravity separator using rotary wiper techniques for maintaining appropriate air bed environment and a rotary controlled air input for bed medium percolation and particle reaction, to provide continuous flow of concentrates through spigots below the air bed. The invention is particularly suitable for separation of gold from alluvial or placer deposits, although it is not limited thereto.
As shown in the drawings, particularly FIGS. 1-4, the air concentrator of the preferred embodiment comprises a circular housing (hereafter referred to as a "module") 50 having a circular channel 16 around its periphery. An annular portion of the module 50 within the channel 16 is divided by radial walls 35 into eight chambers or cells 52. The bottom of each cell 52 is provided with sloping slides 37 so that material within each cell is gravity fed to a respective spigot 38 opening downwardly.
A cylindrical rotor 28, shown in more detail in FIGS. 5 and 6, is provided in the centre of the module 50 and functions as a rotary valve to deliver air to each cell 52 sequentially, at a predetermined pressure, volume and frequency. Minimum clearance 34 is provided between the cylindrical casing 28A of the rotor 28 and the inner vertical edges of cell segment walls 35 so that each cell is in effectively sealed relationship with the rotor 28.
As shown more clearly in FIGS. 5 and 6, the rotary valve 28 comprises a rolled cylindrical casing 28A fitted with a top plate 27 which is mounted on shaft 23 by means of centre boss 19. A vent is formed in the casing 28A by a vertical slot 29 extending along the height of the cylindrical casing 28A, apart from a joining strip 30. The size of the vertical vent opening 29 is governed by the volume/pressure ratio required in the cells 52. The joining strip 30 is a strengthener at the aperture 29 and assists in balancing the rotary valve due to the absence of material at the slot 29.
Shaft 23 is mounted at its top and bottom in bearings 21, 22 located on mounting plate 20 and bottom plate 31 respectively (FIG. 2). The mounting plate 20 is fitted over the central aperture of module 50 and is bolted to the annular plate surrounding the central aperture. Bottom plate 31 is fixed to the bottom of the module 50, and an electric motor 26 is mounted to its underside. The cylindrical casing 28A and shaft 23 of the rotary valve 28 are rotated by the electric motor 26 via coupling 25 and mounted gearbox 24.
The rotary valve 28 is easily removed by unbolting the fasteners at the edge of the mounting plate 20 and the bolts which fasten bearing 22 to bottom plate 31. The coupling 25 simply slips out and the complete rotary valve assembly consisting of the cylindrical housing 28, gearbox 24, top plate 27, shaft 23 and bearings 21, 22 is able to be lifted out of the module (after removal of the wiper bar assembly and the inner top hat drive assembly as explained below). The clearance between the rotor top plate 27 and the mounting plate 20 of the module is also kept to a minimum and this is achieved by machining the rotary valve 28 and fitting the cell segment faces at construction.
A fan unit 32 (FIG. 2), which is mounted beneath the module 50 of the air concentrator by bolting to bottom plate 31, delivers air at substantially constant volume/pressure ratio to the rotary valve 28 via an opening 33 in the base of the module 50. (For clarity, the fan unit 32 is omitted from FIG. 1). The function of the rotary valve 28 is to direct the air at a constant volume/pressure ratio to each cell 52 sequentially at an appropriate constant frequency as the rotor 28 spins. The air is directed into the cells 52 by the vent aperture 29 in the cylindrical rotor 28 as it passes the inner radial aperture of each cell. That is, the vent 29 communicates directly with each cell 52 sequentially, and cyclically. The fan unit 32, rotor assembly 28 and cell 35 are very compact in design and little loss occurs in the delivery of air through minimal ducting. Air flow from the fan unit is continuous and substantially constant, thereby simplifying design criteria for the fan unit.
An annular screen 14 (FIGS. 7 and 8) is mounted on the module 50 above the cells 52 as shown in FIGS. 1 and 2. The screen 14 comprises wire screen material arranged between outer and inner rings 39, 40. These rings sit on the tops of the cell walls 35. Radial support bars 42 of the screen 14 are aligned with respective cell walls 35 to mechanically seal with the tops of the cell walls 35. The screen 14 also includes spaced rings 41 which divide the screen into annular segments 36 which hold bed medium material. (The function of the bed medium is explained below). The rings 41 serve to restrict the flow of the bed medium in a radial direction across the screen.
An apron feed plate 13 (FIGS. 1 and 2) is mounted across the centre aperture of the module 52 to support a cylindrical housing 12 having a drive unit 9, such as an electric motor, mounted therein. The drive unit 9 is bolted to an adaption plate 12A which is welded to the top of the cylindrical housing 12. The drive unit/cylindrical housing assembly can be removed simply by unbolting the fasteners at the edge of apron 13. The drive unit 9 includes a reduction gearbox 9A which is supported by a thrust bearing 10 mounted on top of the adaptor plate 12A. A drive shaft from the gearbox 9A is connected to a hub assembly via cone coupling 11. Thus, in use, the hub assembly and its associated wiper assembly (described below) are rotated about cylindrical housing 12 by motor 9 via gearbox 9A and coupling 11.
The top plate 1 of the hub assembly and the top half of cone coupling 11 are removable by unbolting the fasteners at the outer edge of the plate 1. In this manner, the hub portion can be removed with the complete wiper bar assembly. Alternatively, the top plate 1 can be removed without the wiper bar assembly, if required.
A wiper bar assembly (FIGS. 1, 9 and 10) is mounted to the cylindrical portion 2 of the hub assembly, and comprises inner rings 4,5 and outer ring 8 supported by radial arms 3. The radial arms 3 provide support for the wiper assembly yet allow the required amount of flex. Off-centre radial apron feed bars 6 extend between the cylindrical casing 2 and the inner ring 4, while cell feed bars. 7 extend between the inner ring 4 and outer ring 8. The outer ring 8 is mounted for rotation on rollers 17 about the periphery of the cylindrical module 50 of the air concentrator. Each roller 17 is mounted on an adjustable mounting 18. The height of the rollers is set at the commissioning stage by adjusting the mounts 18 to ensure correct height of the apron feed bars 6 and the cell feed bars 7 relative to the apron 13 and screen 14, respectively. (Further minor adjustments may be required throughout the life of the wiper bars as minimal wear occurs.) Attached to the outer ends of wiper bars 7 and the outer ring 8 by means of support gussets are paddles 15. The paddles 15 convey tailings material along the channel 16 and through apertures 43 (FIG. 3) to a stacker conveyor or similar disposal method. Sufficient room is left between the paddles 15 and the walls of channel 16 so that running material sits on other material thus leaving the channel walls free of wear. The paddles 15 are easily replaced when maintenance is required.
The operation of the air concentrator of the preferred embodiment will now be described with reference to the flow chart of FIG. 11 and the drawings of FIGS. 1 to 10. Material to be processed is introduced onto the top plate of the hub assembly 1 and falls onto the apron surface 13 in a continuous flow. The material is preferably sized prior to processing by the air concentrator, using a conventional screening plant. The size can vary depending on the nature of the ore being processed and the particle size of the minerals being recovered. As the material falls in bulk, it is initially retained by the inner ring 4 of the wiper bar assembly, but as the wiper assembly rotates, the apron feed bars 6 deliver the material at a constant rate to the annular section within ring 5. Ring 5, in conjunction with the wiper bars 7, controls the final feed rate and condition of feed onto the cell beds 36 formed between the rings 39, 40, 41 on the screen 14. The function of the wiper bars 7 is to keep the material in the cell beds 36 level and to keep the feed moving across the beds at a set thickness while tilling the material, causing the movement of gravel and mineral particles to react on the fluidized bed beneath.
The beds of material 36 over each cell 52 are fluidized by the "puffs" or pulses of pressurized air delivered by the rotary valve sequentially to the cells 52. These puffs lift the lighter material while allowing the heavier material to percolate down through the beds. The lighter material is bladed away by the angled wiper bars 7 as they rotate across the fluidized bed, while the heavy concentrates pass through the fluidized bed into the cells 52, and exit through the spigots 38 below the respective cells. The orifices of the spigots 38 are large enough to pass all the concentrates in a continuous flow yet restrict loss of air pressure within the cells 52 to an acceptable minimum. The wiper bar assembly therefore conditions the fluid bed continuously, preventing blow holes and maintaining optimum efficiency of the bed.
The screen 14 above each cell 52 excludes material other than that which is required to pass through the screen. Particles of bedding material will accumulate on the screen 14 to form the bed media 36, the particles of which range in size from above the aperture size of the screen to below the input size of the feed material. Further, the specific gravity of the bedding material is above the normal specific gravity of tails material and below that of the heavy minerals sought.
After a trajectory covering approximately three cells, the tailing material falls into the trough 16 and is carried away by paddles or rakes 15. The heavy materials pass through the fluid beds 36 and are continually bled off through the spigots 38 at the base of each of the cells 52. Larger heavy mineral particles or gold nuggets as such, which are larger than the screen aperture size, will remain in the bed material and can be recovered at leisure. Any buildup of larger heavier particles in the bed medium enhances the functioning of the air concentrator. However, in a practical field situation, the incidence of particles larger than screen aperture size is minimal.
The circular configuration has an inherent advantage in that it allows the progress of material across the bed to slow down as it spreads out over a wider area under the action of the wiper bars 6, 7. This contributes to the heavy minerals settling out when placed on an appropriate environment such as the fluidized bed.
Tests conducted on the illustrated embodiment of the invention have achieved a successful concentration rate of better than 100 to 1 and a recovery rate in excess of 90%. The circular design, although very compact, still allows a large throughput of material. Average throughput of material passing a 6mm screen is 20 cubic metres per hour per 2.5 metre diameter module.
The foregoing describes only one embodiment of the invention, and modifications which are obvious to those skilled in the art may be made thereto without departing from the scope of the invention as defined in the following claims. For example, the number of cells per module can be varied. Furthermore, the modules can be used singularly or in a group configuration, depending on the production required.
INDUSTRIAL APPLICABILITY
The invention is particularly suitable for recovering gold from alluvial and eluvial deposits. It should be noted that the invention is not limited specifically to this type of deposit but is applicable to any deposit which allows for dry separation of heavier particles from lighter material.
The air concentrator of this invention has a number of advantages over previously known air concentrators, including:
(a) The air concentrator is capable of a large volume throughput for its size in comparison to other "wet or dry" concentrators presently available. As air is far less dense than water, a much higher frequency percolation of the bed is obtained, thereby resulting in quicker settling of particles to a static position and subsequent reactivation with less lost time per cycle. Further, air has less molecular adhesion than water and does not carry away the very fine heavy particles, an unwanted effect which overrules the gravitational effect in wet concentrators. Hence far more material can cross the air bed efficiently than in lower frequency concentrators or batch types which have to be stopped on a regular basis and cleaned out of accumulated concentrates.
(b) The air concentrator has few moving parts. Only three principal components move, two of which (the rotor and fan) incur virtually no wear at all, while the third (the wiper system) only suffers wear on bars which are hardened and have quite a long life. The other secondary moving parts are the small rollers, motors and gear box drives which are lifetime units as such.
(c) As the concentrator has few moving parts, it requires low maintenance.
(d) The radial mode of processing the deposit allows for a compact design.
(e) The air concentrator has a simple construction consisting of mainly mild steel fabrication and utilizes a circular configuration for most of its structural components. The fan and drive units are bolt-on items.
(f) A high degree of ore concentration can be obtained, typically better than 100 to 1.
(g) Heavy minerals are extracted continuously as they are recovered from the primary ore, unlike many known air concentrators which are of a "batch" type and need to be shut down regularly to clear concentrates as necessary.
(h) The concentrator of this invention has a high recovery rate in comparison with other "wet" and "dry" processes presently available.
(i) The concentrator is easily transported, thereby making it suitable for low cost mobile mining in placer deposits where primary ore is shallow and constant moving is necessary to stay at the face of the deposit.
(j) By using air as the separating medium in preference to water, far less infrastructure is required, providing substantial savings in direct costs such as pipelines, pumps, dam construction, etc., and indirect costs such as delays in waiting for rain to fill dams and associated problems. (The other infrastructure directly related to the concentrator is a mobile power source to drive the unit.)
(k) The concentrator is not labor intensive to operate, and normally only one operator is required to feed the plant per shift.
(l) As a result of (a)-(k) above, production costs are reduced.
(m) The air concentrator is environmentally acceptable. | An air concentrator for dry separation of gold and other heavy minerals from alluvial deposits comprises a housing having a number of open-topped chambers arranged in a ring-like configuration and surmounted by a screen having rings thereon forming annular arms radiating from a hub sweeps over the screen beds. Air under pressure is fed sequentially and cyclically to the chambers by a rotary valve located centrally of the ring of chambers. The deposit is fed over the hub and is swept outwardly over the beds on the screen by the wiper arms, where it is fluidized by pulses of air from the subjacent chambers enabling particles of gold and heavy minerals to settle down to the bottom of the beds by gravitational stratification, and if sufficiently small, pass through the screen for collection through spigots in the bottom of the chambers. | 1 |
FIELD OF THE INVENTION
This invention relates generally to a method of repairing cracks and small apertures in roadways, and more particularly, to a method of using divergent materials in repairing roadway cracks and imperfections. More particularly, the invention relates to use of an organic-based material with a petroleum emulsion.
BACKGROUND OF THE INVENTION
Cracks often develop in pavement roadways. Such roadways are constructed of different types of surfaces such as bituminous concrete, asphalt binders, asphalt emulsions and cement concrete. Cracks result from a variety of conditions such as, inter alia, poor quality base materials, lack of or inadequate compaction, surface movement, oxidation, overloading, and water penetration. Some cracks result from expansion and contraction due to weather conditions including climatic temperature changes. The widest and deepest cracks often appear at the longitudinal paving seams in bituminous concrete, typically caused by cold rolling. Some other types of cracks are intentionally made. For example, utility excavations involve cuts into roadways. These cracks are located at the perimeter of the excavation itself. Other small apertures, e.g., small potholes and pavement delaminations may also be fixed using crack repair methods. With scheduled crack repairs and maintenance, pavement surface life can be greatly extended, postponing the need for repaving the entire roadway surface.
Crack and aperture repairs may be needed urgently for safety reasons or where traffic conditions make lengthy road closures inconvenient or in some cases unacceptable. These repairs are ideally made as quickly, and as economically, as possible.
There are various methods of making repairs of such cracks. Hot crack "sealing" is the most common method in which the crack is first cleaned by a mechanical device or by the application of compressed air. The crack is then filled with a hot sealing substance and blotted with a cover material. The next step in the process is to allow the site to cure. This process is usually performed in temperatures well above freezing.
Preparation of the hot sealing substance requires various mixing steps at elevated temperatures and continued agitation of sealing materials which must be placed in heated oil in double-jacketed kettles. This process is costly due to the specialized equipment needed, and the substantial labor requirements involved. The asphalt-based and additive enhanced materials are also comparatively expensive.
More recently, cold processes have been developed which can be performed in colder temperature conditions and do not require the specialized equipment needed for hot crack sealing. However, problems have arisen with such processes especially in connection with dust clouds forming during the repair process. More specifically, known cold processes include filling the crack or aperture with a petroleum emulsion until voids no longer exist. The petroleum emulsion is then covered with a layer of a mineral filler. The mineral filler typically consists of sand, stone dust, stone-sand, limestone, rock "screenings", washed screenings and the like.
In this process, the repairer fills the site with petroleum emulsion and then applies the mineral filler on the surrounding surface as a coating layer. However, the mineral filler produces a great deal of airborne dust. A dust cloud can be formed by traffic in the lane and, it is then aggravated by the passage of traffic in other lanes. This can produce extremely low visibility conditions that may lead to road closure.
In addition to the dust problems, there are other problems associated with cold processes. More specifically, the mineral filler can be quite expensive. It is also rather heavy causing labor requirements to be substantial. Moreover, the accumulation of the mounded mineral filler combined with the petroleum emulsion can leave a ripple effect on the roadway surface, creating a rough surface for vehicular traffic.
One advantage to using the cold process relates to roadway rejuvenation. Specifically, roadways are constructed and repaired with the additional goal of longer road surface life. Sometimes a roadway can be later rejuvenated when repair material is subsequently spread out by tires of passing vehicles. The materials fill in hairline cracks which may be beginning to form in the roadway. This usually occurs, if at all, after the winter when temperatures begin to warm and a repaired crack site becomes somewhat tacky. The tires of passing vehicles pick up materials and spread them to other areas of the pavement. However, whether this occurs with known cold processes can be unpredictable.
There remains a need for a method of repairing cracks in roadways which does not produce dangerous airborne dust and does not result in large amounts of road closure time. There remains a further need for a process that is less costly in that it utilizes materials that are comparatively less costly than prior known materials and such materials, being lighter, involve fewer labor requirements than known prior methods. Another need exists for a process which results in a smooth surface with little ripple effect. There remains a further need for a method which increases the likelihood of roadway rejuvenation when materials are subsequently spread by passing vehicles.
SUMMARY OF THE INVENTION
These and other needs are satisfied by the method of the present invention which is a low cost, cold process of repairing roadways that utilizes recycled materials in a cover blotter step of the process. More specifically, the method of the present invention includes filling a suitable repair site with a petroleum emulsion until the emulsion fills up the site and overlaps the edges of the aperture to a predetermined amount. Thereafter, the method includes the step of applying a cover blotter consisting of an absorbent, highly porous, spreadable bulk material, including an organic, vegetatively-derived mulch as defined herein, alone or in combination with screened pavement sweepings that include organic material. Without being bound to any particular theory or mechanism, it is believed that the curing process is enhanced by the presence of the cover blotter which in part performs a blotting function by both adsorbing and absorbing the continuous phase of the emulsion.
After the cover blotter is applied, the site is re-opened to traffic. The passage of traffic over the repaired site will aid in the capture of cover blotter particles by the petroleum emulsion, and serves to smooth out the repair site. Thus, there is an advantage to early re-admission of traffic onto the roadway in contrast to repair sites which involve layers of loose gravel, sand or other mineral filler which cannot be left exposed on high speed roadways, due to the dust problem discussed herein.
As noted, with the cover blotter material of the present invention, dust is greatly reduced. Moreover, there is considerably more adherence of the cover blotter material, compared to the mineral filler into the petroleum emulsion. Thus, sever mounding does not occur in the repaired area, and the ripple effect encountered using other methods is greatly lessened. The inventive process results in a more smooth road surface.
Organic mulch is considerably lighter in weight than mineral fillers, therefore greater quantities of the material can be hand-placed at a given unit labor cost compared with known mineral filler. Further, the organic mulch is readily available as a product of recycling in large quantities at little or no cost. For example, some forms of organic mulch may be leaves collected by municipalities, such municipalities typically are readily willing to dispose of this type of material. Similarly, the pavement sweepings are readily available at the site at no cost. Additionally, loose mulch swept up with pavement sweepings from one repair site may be later recycled and used at a different repair site.
BRIEF DESCRIPTION OF THE DRAWING
The above and further advantages of the invention may be better understood by referring to the following description in conjunction with the accompanying drawing, in which the FIGURE depicts a roadway with a crack to be filled and sealed in accordance with the method of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The FIGURE depicts a crack 10 in a bituminous concrete roadway 12. The crack 10 is about two to three inches in depth as designated by the dimension 14 in the FIGURE. The method of the present invention is preferably used with cracks, delaminations, and small type potholes of such a depth, in various types of bituminous pavements, or cement concrete pavements. However, the scope of the invention is not confined to repair sites of such a depth.
In accordance with the method of the present invention, the crack 10 in the pavement is filled with a petroleum emulsion 20. The term "petroleum emulsion" as used herein shall include petroleum emulsions, asphalt emulsions or modifications to such emulsion, including anionic, cationic and nonionic materials. A suitable petroleum emulsion is a product sold under the trademark "CRF" by Golden Bear Oils Specialties of Los Angeles, Calif. It is preferred that petroleum emulsions used in the process of the present invention have a viscosity range, as will be understood by those skilled in the art, on asphalt emulsions' residue by ASTM Standard D-244 of 10 to 3,000 poises at 60 degrees C. (Celsius). (With respect to the CRF product, conversion of cSt (Centistokes) viscosity of the CRF product at 60 degrees C. to poises is about 1 poise=100 cSt.). It is also preferred that the petroleum emulsion used in the process of the invention have a residual value of between about 55 and 75 percent (by weight).
The crack 20 is filled with the petroleum emulsion until it substantially overlaps the petroleum emulsion onto the pavement surface of the roadway 12 on each side of the aperture. For example, but without being bound by the example, the overlap may measure approximately one inch to six inches or further, as desired in a particular application. The overlapping portions are illustrated in the figure with reference characters 24 and 26.
After the petroleum emulsion 20 has been filled and overlaps the crack 10 in the roadway, the repairer will then cover the crack with a mounded layer of a cover blotter material 30. The term "cover blotter" material as used herein shall include any mulch material which is an organic, vegetatively-derived substance, such as mulched leaves, a combined mulch formed of leaves, grass trimmings and garden trimmings, tree bark mulch, tree mulch, mulched wood, hay or sawdust, and the like. Such materials are available commercially as well as from certain municipal refuse or waste management facilities as recyclables. The cover blotter material preferably includes aged mulch which can provide heat to the curing process although this is not required. In addition, the term "cover blotter" as used herein also includes pavement sweepings including leaves and so forth that drift to the curbside. Further, a combination of loose mulch and pavement sweepings swept up from one repair site can be recycled and used for a subsequent repair project. Preferably, the mulched material and the pavement sweepings are screened or graded to obtain particulates of a desired size.
The cover blotter material 30 is applied such that it is mounded over and covers substantially all of the petroleum emulsion 20, as designated by the dashed lines 32 in the FIGURE. The cover blotter material performs a blotting function by exhibiting a wicking action in that it is capable of both adsorbing and absorbing the continuous phase of the emulsion. After mounding the cover blotter material over the petroleum emulsion, preferably the tires of a truck or other large vehicle are driven over the site to compress the cover blotter into the emulsion. Thereafter, the site is checked for substantial total liquid blotting. If any liquid remains visible, additional cover blotter material is added until no further liquid remains. The cover blotter material enhances the curing process as a portion of the cover blotter material 30 is "grabbed" by the petroleum emulsion and coagulates into the emulsion, forming a cover on the surface of the roadway 12.
In certain circumstances, various mineral fillers as described herein may be combined with the cover blotter material in a desired proportion to increase consistency of the cover blotter. This thickens the cover blotter material, and provides greater stability in the case of deeper or wider cracks.
After the petroleum emulsion and cover blotter material have been applied, the site is then immediately reopened to traffic. This is possible as there is very little airborne dust created by the cover blotter. As the traffic passes over the site, the rubber tires serve to continuously work the petroleum emulsion into the softened roadway. Without being bound to any particular theory or mechanism, it is believed that the cover blotter material is grabbed into the petroleum emulsion, and as the water in the emulsion evaporates, the cover blotter fills any interstices left in the emulsion so that there are minimal air voids in the repaired site. Thus, there is an advantage to early re-admission of traffic to the roadway.
The cover blotter material of the present invention remains partially suspended in the emulsion such that, upon softening of the repaired site after the winter cycle, there is increased adhesion of material to passing tires. This serves to spread the material about the nearby roadway, serving to rejuvenate the roadway by re-sealing hairline cracks and the like. This tends to increase density leading to longer road surface life.
To further enhance the disclosure and to illustrate the method of the present invention, an example will be considered. It should be understood however, that the example illustrates one embodiment of the invention and the invention is not limited to the scope of the example.
EXAMPLE
In accordance with the method of the present invention, a repairer examines a crack, delamination or small-type pothole in the pavement to determine whether it is the appropriate size for the method of the present invention. Once this determination has been made, there is no need to clean the site or otherwise prepare the site for the sealing process. The repairer applies a petroleum emulsion to the site opening. The petroleum emulsion used in the example is the CRF product having the specifications outlined herein. Petroleum emulsion is filled into the crack and overlaps the crack by about 1 inch beyond the edge of the aperture. A cover blotter material consisting of organic mulch mixed with a portion of screened pavement sweepings is then placed over all the exposed petroleum emulsion areas. The cover blotter material, defined herein, is mounded to blot any excess liquid. A dump truck is then driven over the repair site. The flexible tires serve to smooth out the site more evenly than conventional rollers. Seams and ridges, which can be left by a roller, are not produced. The site is then re-opened to traffic, and as the traffic passes, the rubber tires will further serve to work the surface and smooth out the repaired site to level it with the roadway and the ripple effect is greatly decreased.
The method of repairing cracks in roadways described herein is an economical method in that it uses recycled materials which are, in certain circumstances, available free of charge from municipal refuse facilities. If, on the other hand, the material is purchased commercially, it is typically significantly less costly than the conventional mineral filler material. Furthermore, the cover blotter disclosed herein produces much less dust during the application process than is produced during known prior methods. This process thus leads to fewer, and shorter road closures. Additionally, the process involves a lighter weight material which is more easily spread. Accordingly, labor costs are greatly reduced.
The foregoing description has been limited to a specific embodiment of this invention. It will be apparent, however, that variations and modifications may be made to the invention, with the attainment of some or all of its advantages. Therefore, it is the object of the appended claims to cover all such variations and modifications as come within the true spirit and scope of the invention. | A method of repairing cracks and apertures in a roadway, including the step of filling the crack or aperture with petroleum emulsion and overlapping the crack or aperture with the emulsion to preferably up to one inch or greater beyond the edge of the aperture on each side; applying a layer of an organic, cover blotter material and mounding said cover blotter material to cover substantially the entirety of said petroleum emulsion layer. The emulsion penetrates and softens the pavement surrounding the site. When the emulsion cures, it coagulates with the cover blotter material. The roadway is reopened to allow traffic to pass over the site to further compact and smooth out the roadway repaired surface to eventually form a pliable smooth patch. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to semiconductor packages and assemblies and methods for forming the same.
BACKGROUND
[0002] IC (integrated circuit) chips are semiconductor or other suitable chips that have an integrated circuit formed thereon. IC chips have microscopic input/output pads through which the integrated circuit is coupled to the outside world. The IC chips must be assembled in packages or other structures before being coupled to external devices and used in various applications. In the rapidly-advancing semiconductor manufacturing industry, and in the electronics industry as well, there is a push to increase integration levels and decrease device sizes. This is reflected in smaller and more compact IC chips and smaller components that combine to form the electronic devices in which the IC chips are used. As such, the packages that accommodate the chips must be accordingly miniaturized. Due to the increased complexity of each IC chip, the number of I/O (input/output) connections and pads also increases accordingly. Each I/O pad of the IC chip must be coupled to a conductive contact in the package in order to be coupled to other components, ground and power sources, and to provide and receive electrical signals to and from other components, i.e., communicate with the outside world. It is therefore a challenge to incorporate more input/output pads in a reduced area.
[0003] One of the shortcomings of advancing technology is that the need to provide smaller I/O pads and a smaller pitch for the I/O pads is limited by the wire dimensions of the wires typically used to connect the I/O pads of the IC chip to the package substrate. Gold is a commonly used bonding wire material. If the conventional, relatively thick bond wires are used and coupled to pads having a reduced pitch, the adjacent wires and pads can become shorted destroying device functionality. Conversely, the use of smaller wires will result in poor electric performance, for example increased resistance, when such wires are coupled to pads of reduced dimensions.
[0004] It would therefore be desirable to provide a bond pad arrangement having a reduced pitch, i.e., accommodating a greater number of I/O bond pads in a given area and increasing device and package complexity and compactness, without sacrificing degraded electrical performance or destruction of device functionality.
SUMMARY OF THE INVENTION
[0005] To address these and other needs and in view of its purposes, the present invention provides, in one aspect, a semiconductor package comprising a chip mounted on a substrate. The package includes a plurality of wires, each connecting a contact pad on the substrate to an associated bond pad on the chip. The plurality of wires include signal lines coupling signal contact pads on the substrate to signal bond pads on the chip and including a first thickness, and ground lines and power lines coupling ground contact pads and power contact pads, respectively, on the substrate to ground bond pads and power bond pads, respectively on the chip and including a second thickness. The second thickness is greater than the first thickness.
[0006] According to another aspect, the invention provides a semiconductor package comprising a chip mounted on a substrate. The package includes a plurality of wires, each connecting a contact pad on the substrate to an associated bond pad on the chip. The plurality of wires include signal lines coupling signal contact pads on the substrate to signal bond pads on the chip and including a first thickness, and ground lines and power lines coupling ground contact pads and power contact pads, respectively, on the substrate to ground bond pads and power bond pads, respectively on the chip and including a second thickness. The second thickness is greater than the first thickness and the ground and power bond pads on the chip are staggered with respect to the signal bond pads on the chip. The ground and power contact pads on the substrate have a pitch that is greater than the pitch of the signal contact pads formed on the substrate.
[0007] According to another aspect, the invention provides a semiconductor package comprising a chip mounted over at least two package substrates that may be stacked over one another. The semiconductor package includes a plurality of wires, each connecting a bond pad on the chip to an associated contact pad. The plurality of wires include signal lines coupling signal bond pads on the chip to signal contact pads and including a first thickness, ground lines coupling ground bond pads on the chip to ground contact pads and including a second thickness, and power lines coupling power bond pads on the chip to power contact pads and including the second thickness. The second thickness is greater than the first thickness and the at least two package substrates include an inner package substrate and a peripheral package substrate. Each of the signal contact pads, ground contact pads and power contact pads are disposed on one of the package substrates.
BRIEF DESCRIPTION OF THE DRAWING
[0008] The present invention is best understood from the following detailed description when read in conjunction with the accompanying drawing. It is emphasized that, according to common practice, the various features of the drawing are not necessarily to scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity. Like numerals denote like features throughout the specification and drawing.
[0009] FIG. 1 is a cross-sectional, side view illustrating the various bond wires according to the invention;
[0010] FIG. 2 is a top view showing various bond wire connections according to an exemplary embodiment of the invention;
[0011] FIG. 3 is a top view showing various bond wire connections according to another exemplary embodiment of the invention;
[0012] FIG. 4 is a top view showing an exemplary staggered bond pad arrangement according to the invention;
[0013] FIG. 5 is a cross-sectional, side view of another exemplary embodiment illustrating the various bond wires according to the invention; and
[0014] FIG. 6 is a top view showing various bond wire connections according to the exemplary embodiment shown in FIG. 5 .
DETAILED DESCRIPTION
[0015] The present invention is directed to IC chips mounted in or on a semiconductor package and having bond pads thereon. The bond pads are electrically and physically coupled to contact pads on the package substrate via bond wires. The bond wires may be formed of the same or different materials and include different thicknesses. The semiconductor package may include one or more package substrates which may be stacked over one another in some embodiments.
[0016] Referring to FIG. 1 , IC chip 3 is mounted on package substrate 1 and is centrally disposed in the illustrated embodiment. According to other exemplary embodiments, IC chip 3 may be disposed in locations other than the center of package substrate 1 . According to other exemplary embodiments, IC chip 3 may be disposed within a recess formed in package substrate 1 . IC chip 3 includes an integrated circuit or semiconductor device that may carry out any of various functions.
[0017] IC chip 3 includes a plurality of bond pads which function as the inputs/outputs of the integrated circuit/semiconductor device formed on IC chip 3 . The bond pads include power/ground bond pads 7 and signal bond pads 17 in the illustrated embodiment and the respective bond pads may be formed of aluminum, gold, various metal alloys or other suitable conductive materials used in the semiconductor manufacturing industry. The bond pads are generally disposed peripherally with respect to IC chip 3 (see FIGS. 2-6 ) but can be disposed in any location according to the various embodiments of IC chips 3 that may be produced. In various exemplary embodiments such as will be illustrated in FIGS. 2-6 , the bond pads are disposed in one or more rows that may be generally parallel to and proximate to the peripheral edges of IC chip 3 . The inputs/outputs of a semiconductor device are connected to ground, power sources and signal lines. The bond wires that couple the bond pads on IC chip 3 , to contact pads on package substrate 1 include signal lines 9 and power/ground lines 11 . Power/ground lines 11 include thickness 25 which is greater than thickness 27 of signal lines 9 . Power/ground lines 11 represent bond wires that couple power/ground bond pads 7 of IC chip 3 to a ground source or a power source through power/ground contact pads 5 formed on package substrate 1 . That is, power/ground contact pads 5 represent pads that are coupled to a power or ground source. Signal lines 9 couple signal bond pads 17 of IC chip 3 to an electrical signal by way of signal contact pads 15 on package substrate 1 . That is, signal contact pads 15 on package substrate 1 deliver and/or receive electrical signals to/from IC chip 3 via signal lines 9 .
[0018] Signal lines 9 and power/ground lines 11 may be formed of the same or different materials and may be formed of gold, Al, AlCu, Cu, or other metal alloys or information-carrying media. Each of signal lines 9 and power/ground lines 11 may be considered bond or bonding wires. In various exemplary embodiments, thickness 25 of signal lines 11 may be about 1.1 to about four times as great as thickness 27 of signal lines 9 . In one exemplary embodiment, thinner signal lines 9 may include a thickness no greater than about 0.5 or 0.6 mils and the thickness may be 0.4 mils in one exemplary embodiment. The relatively thicker power/ground lines 11 include thickness 25 which may be about 0.8 mils or greater. The relationship between the relatively thicker power/ground lines 11 and relatively thinner signal line 9 may be expressed as the ratio of the number of I/O lines, the ratio of the signal/power/ground lines being 4/1/1 according to an exemplary embodiment in which the power/ground lines 11 deliver a power of 100 watts and each signal line delivers a power of 25 watts. According to this embodiment in which 4 signal lines carry the equivalent power of one power line and one ground line, the power/ground lines 11 must be suitably larger than the corresponding signal lines 9 . It can be seen that relatively thicker power/ground lines 11 overlap relatively thinner signal lines 9 in the illustrated embodiment.
[0019] FIGS. 2 and 3 are plan views showing various arrangements for coupling the contact pads 5 and 15 to bond pads 7 and 17 . FIG. 2 shows the bond pads, including power/ground bond pads 7 and signal bond pads 17 forming a single peripheral row around each of the edges 21 of IC chip 3 . In the illustrated embodiment of FIG. 2 , contact pads 5 and 15 are arranged in a single row that extends outside each of edges 21 and no overlapping of bonding wires occurs. Power/ground bond pads 7 include a greater pitch than signal bond pads 17 and power/ground contact pads 5 include a greater pitch than signal contact pads 15 .
[0020] FIG. 3 shows another exemplary arrangement of a semiconductor package including IC chip 3 centrally disposed on package substrate 1 . The contact pads-power/ground contact pads 5 and signal contact 15 are disposed in a plurality of rows about peripheral edge 21 of IC chip 3 . In particular, signal contact pads 15 are disposed in row 41 and power/ground contact pads 5 are disposed in row 43 , external to row 41 . As such, signal contact pads 15 that are disposed peripherally about IC chip 3 and power/ground contact pads 5 are disposed peripherally about signal contact pads 15 . In many locations, power/ground lines 11 overlap signal lines 9 . Pitch 33 of power/ground contact pads 5 is greater than pitch 37 of signal contact pads 15 . FIG. 3 also illustrates an aspect of the invention that power/ground bond pads 7 are staggered with respect to signal bond pads 17 . This feature is shown more clearly in FIG. 4 .
[0021] Referring again to FIG. 2 , pitch 49 of power/ground bond pads 17 is greater than pitch 47 of signal bond pads 17 . In one exemplary embodiment, pitch 47 may be about 50 microns or less and pitch 49 may be 40 microns or greater. Spacing 51 between adjacent signal bond pads 17 will be generally less than spacing 53 between adjacent power/ground bond pads 7 in most exemplary embodiments. Spacing 51 between adjacent signal bond pads 17 may be about 35 microns or less and in one embodiment may be 9 microns. Spacing 53 between adjacent power/ground bond pads 7 may be about 6 microns or greater and may be about 44 microns in one embodiment. Such values are intended to be exemplary only.
[0022] FIG. 4 shows signal bond pads 7 arranged in internal row 57 and power/ground bond pads 17 disposed in peripheral row 59 which is closer to peripheral edge 21 of IC chip 3 and it can be seen that signal bond pads 7 in internal row 57 are staggered with respect to power/ground bond pads 17 in row peripheral 59 . The particular arrangement shown in FIG. 4 is intended to be exemplary only.
[0023] FIGS. 5 and 6 illustrate another exemplary embodiment according to the invention. According to this exemplary embodiment, IC chip 3 is mounted over stacked package substrates in the illustrated semiconductor package. The stacked package substrates include inner package substrate 101 and outer or peripheral package substrate 105 . IC chip 3 is centrally disposed with respect to both inner package substrate 101 and peripheral package substrate 105 in the illustrated embodiment but according to other exemplary embodiments, IC chip 103 may be disposed in locations other than the center of the semiconductor package. IC chip 3 includes power/ground bond pads 7 and signal bond pads 17 , both as previously described. In the illustrated embodiment, power/ground bond pads 107 are disposed in internal rows with signal bond pads 17 disposed in peripheral rows but other arrangements may be used in other exemplary embodiments.
[0024] Power/ground lines 11 and signal lines 9 are as previously described. In the illustrated embodiment, power/ground contact pads 5 are formed on peripheral package substrate 105 with signal contact pads 15 formed on inner package substrate 101 . As such, power/ground contact pads 5 are disposed outside signal contact pads 15 and some of power/ground lines 11 extend over, i.e., overlap signal lines 9 . According to other exemplary embodiments, IC chip 3 may be disposed on various other arrangements of one or more package substrates to form a semiconductor package according to the invention. Minimum pitch 111 of signal contact pads 115 disposed on inner package substrate 101 is less than minimum pitch 113 of power/ground contact pads 5 formed on peripheral substrate 105 . In one exemplary embodiment, minimum pitch 111 may be 35 um and minimum pitch 113 may be 80 um but such dimensions are intended to be exemplary only.
[0025] The preceding merely illustrates the principles of the invention. It will thus be appreciated that those skilled in the art will be able to devise various arrangements which, although not explicitly described or shown herein, embody the principles of the invention and are included within its spirit and scope. For example, signal bond pads 17 and power/ground bond pads 7 may be disposed in different arrangements on IC chip 3 . For example, they may be formed in the same row ( FIG. 2 ) or in separate rows ( FIGS. 3 and 4 and FIGS. 5 and 6 ). The same is true for power/ground contact pads 5 and signal contact pads 15 . For example, rather than being distanced approximately the same distance from peripheral edge 21 of IC chip 3 , as in FIG. 2 or whereby power/ground contact pads 5 are peripherally disposed about signal contact pads 15 , according to another exemplary embodiment, signal contact pads 15 may be disposed peripherally about a row of contact pads that includes at least some power/ground contact pads 5 . With respect to the stacked package substrate embodiments such as illustrated in FIGS. 5 and 6 , various other exemplary embodiments may include inner package substrate 101 including both power/ground contact pads 5 and signal contact pads 15 and/or peripheral package substrate 105 may include both power/ground contact pads and/or signal contact pads 15 . The illustrated embodiments are intended to be representative, and not limiting of the various arrangements of the invention.
[0026] Moreover, all examples and conditional language recited herein are principally intended expressly to be only for pedagogical purposes and to aid the reader in understanding the principles of the invention and the concepts contributed by the inventors to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. All statements herein reciting principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents and equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure.
[0027] This description of the exemplary embodiments is intended to be read in connection with the figures of the accompanying drawing, which are to be considered part of the entire written description. In the description, relative terms such as “lower,” “upper,” “horizontal,” “vertical,” “above,” “below,” “up,” “down,” “top” and “bottom” as well as derivatives thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description and do not require that the apparatus be constructed or operated in a particular orientation. Terms concerning attachments, coupling and the like, such as “connected” and “interconnected,” refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise.
[0028] Although the invention has been described in terms of exemplary embodiments, it is not limited thereto. Rather, the appended claims should be construed broadly, to include other variants and embodiments of the invention, which may be made by those skilled in the art without departing from the scope and range of equivalents of the invention. | A semiconductor package provides an IC chip on at least one package substrate and including signal bond pads, ground bond pads and power bond pads. The package substrate includes signal contact pads, ground contact pads and power contact pads which are respectively coupled to signal bond pads, ground bond pads and power bond pads formed on the IC chip. The contact pads are coupled to the associated bond pads by a bonding wire. The bonding wires that connect the power and ground pads have a thickness that is greater than the thickness of the bonding wires that couple the signal pads. The various bond pads on the IC chip may be staggered to provide for enhanced compactness and integration. The package substrates may be a plurality of stacked package substrates. | 7 |
This is a continuation of application Ser. No. 07/847,703, filed on Mar. 5, 1992, abandoned.
BACKGROUND OF INVENTION
This invention consists of two distinct themes:
a buckling slender column used as a spring with nearly constant force; and
a printed circuit array of springs, particularly non-cantilever or non-planar springs.
In some current electromechanical applications there is a requirement for an array of springs which can exert near-constant force over a considerable range of deflection. In varying applications a single spring element may be utilized. In other representative applications the springs may be closely spaced in an array consisting of 2 rows by 2 columns for a total of 4 spring elements, up to and possibly exceeding 15 rows by 15 columns, for a total of 225 spring elements. The requirements also provide that the end product be simple in design, easily manufacturable, and possess the desired non-linear properties.
This invention thus provides a printed circuit of springs which integrates a dense array of many functionally distinct springs into one thin metal sheet. The sheet is folded so individual springs protrude perpendicularly from the sheet. An individual spring has multiple columns which bend by buckling during deflection (compression). For a significant range of deflection, the spring force is nearly constant, and there is minimal lateral sideways force and displacement.
A dense array of numerous discrete springs according to previous technology imposes a penalty in complexity, fabrication, assembly and cost. By contrast, a goal of this present invention is to improve simplicity, fabrication, assembly and cost.
It is known that a collimated beam axially loaded will initially be stiff until sufficient lateral deflection of some portion of the beam occurs to cause the member to "buckle", creating a drastic change in deflection per additionally applied load. Building upon that principle, it has been discovered that two centrally joined opposing flat beams, having a slightly outward bowed cross section could exert a nearly constant axial force over a relatively large range of displacements, and the coupling of the beams allows the opposing forces to cancel any lateral displacement of the central axis, but act additively to exert a constant force against the perpendicularly applied load.
It was discovered that variations in the basic parameters of thickness, material type, and width of legs will alter the spring rate. Varying height and selectively removing material to balance internal stresses upon deflection produces an extended near-constant-force band.
Testing of this invention has shown that the unitary array design greatly improves manufacturability over prior art designs utilizing discrete components such as a series of coil springs, and the unitary design also offers a substantially higher spring rate than would a comparably sized cantilever spring occupying the same volume.
Standard coil and cantilever springs produce a linear or extra-linear increase in force with deflection while the opposite--a sub-linear increase in force with deflection--has been found to be true for the buckling beam type spring of the present invention.
Although the spring array was designed to serve a specific purpose, the versatility of design and performance characteristics suggest numerous application; some using existing designs and others using modified designs.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a segment of an array of springs according to a first embodiment of the invention;
FIG. 2 illustrates a typical force vs deflection curve of a spring constructed in accordance with the present invention;
FIG. 3 is a perspective view of a portion of an array of springs according to a second embodiment of the invention;
FIGS. 4a and 4b illustrate the profile of springs constructed in accordance with the second embodiment of the invention in the configuration as initially formed and in the fully assembled form;
FIG. 5 is a perspective view of a segment of an array of springs constructed in accordance with a third embodiment of the invention; and
FIG. 6 is a perspective view of a segment of an array of springs constructed in accordance with a fourth embodiment of the invention.
FIG. 7 illustrates a flat sheet for forming and array of 6 rows and 6 columns of springs, similar to those of FIG. 1.
FIG. 8 is an isometric view of an array of 6 rows and 6 columns of springs formed from the flat sheet of FIG. 7.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 depicts a first embodiment 10 of the basic spring array design. The design consists of a series of arched leaf springs. A unitary sheet 12 of appropriate material is patterned and formed to produce an array of springs.
The fabrication process consists of first selectively removing material to form the necessary pattern from material having the desirable properties, including high spring rate. The material should be laid out such that bend lines will not fall parallel to the grain direction of the material, and ideally will fall 90 degrees to the grain direction.
Critical to the performance of the springs of the present invention is that the spring force must be produced by the entire length of the side member or leg and not concentrated to a small portion of the leg. To achieve this, it is imperative that the profile of the legs be a gradual arc with no abrupt form changes or defects in the active region. Because of the high spring rate of the selected material, it would be difficult to repeatedly obtain a large precision formed radius. A natural bow is produced in the straight region of the leg at the time of assembly, coerced by the higher stresses present at the upper and lower radii 24, 26, 28, and 30, and the subsequent conversion of angles from obtuse to acute and from acute to obtuse respectively.
Forming of the structure of the springs is accomplished in three stages. The initial forming is done on precision forming dies. This step serves to form the four radii on each row of parts, one complete row at a time. Forming in accordance with the preferred embodiment of the present invention is symmetrical about the central vertical axis. The top two radii 24, 26 provide a gradual transition from the flat top portion to the side members or legs. The bottom radii 28 and 30 are formed opposite the top two. When completed, the cross section shows substantially vertical side walls projecting upwardly from a base portion and topped by a short portion, parallel to the base, the appearance of which can be said to resemble a top hat. The second forming stage establishes a natural bow in the legs of the springs and occurs when the bases of each spring are secured into position, changing the obtuse formed upper angles to acute angles and the acute formed lower angles to become obtuse angles. The bow occurs because the internal stresses in the die formed radii have a greater resistance to deformation than the unformed sides, causing the sides to displace. This assures the largest possible radius for the most desirable performance. The third stage of forming involves deliberately over-stressing the spring by deflecting it to its maximum practical deflection which induces residual stresses favorable for consistent performance in a commonly used method called cold-setting. Further understanding of the method of forming the spring array of the present invention will be facilitated by reference to FIG. 7, which illustrates a flat sheet patterned and cut preparatory to forming into an array of 6 rows by 6 columns of elements, similar to those of FIG. 1. FIG. 8 illustrates the sheet of FIG. 1 folded and formed into the final array.
Referring to FIGS. 1, bands 15 project upwardly from the face of sheet 12 and are formed into springs 16. In order to provide the bands, a first plurality of pairs of parallel slits 14 are cut into the surface of sheet 12. The separation of the pairs of slits 14 corresponds to the width of the bands 15 and the spacing between adjacent bands alternately that are later formed into individual springs 16. A second plurality of slits 18, oriented perpendicular to the first slits 14 are cut between adjacent springs 16 and between the end springs in a row and the edge of the sheet of material 12. A portion of the material between the slits 18 is removed and the edges are bonded together using appropriate bonding techniques. A backing plate 36 may be optionally added for stability. Any commonly used method may be used for securing the joint, such as adhesive bonding, resistance welding, brazing, or energy beam welding.
Altering various geometric and material parameters will affect the spring rate, the force-deflection curve, or both. The following criteria all seem to apply:
Thickness: Proper material thickness is essential to obtaining a large near-constant-force band. The higher the ratio of height to thickness, the longer the near-constant-force band. A ratio of 150:1 performed satisfactorily on test parts.
Width of Leg: Increasing the width of the legs will increase the force. Because more force is delivered per unit of deflection, the force-deflection curve will be steeper, and the near-constant-force region will shrink. It should also be noted that two separate legs whose sum of widths is equal to a solid, wider leg, will not deliver the same amount of force because of internal reactive stresses.
Height: As stated previously, the height to thickness ratio is an important parameter for maximizing the near-constant-force band. The ratio of height to width is not definitive, but ratios between 1.5:1 and 4:1 have performed satisfactorily on test parts. If the height is too short, the member will have limited travel and be very stiff. If the height is too tall, the member will be unstable. The greater the height, the longer the near-constant-force band will be. Taller legs will also require greater spacing as their lateral displacement is greater.
Cross Sectional Geometry: By selectively removing material from the face of the legs in low stress areas causing a redistribution of stresses to a more balanced state, it is possible to improve performance, remaining in the near-constant-band for longer periods of time.
It should be noted that, with respect to the parameters of thickness, leg width, height and cross-sectional geometry, the specific figures mentioned above merely represent those used satisfactorily in test parts. These figures are not to be considered optimum, and numerous values may be expected to function in a fully satisfactory manner.
A planar, load-contacting top portion 20 has a pair of parallel side radii 22 as shown. Top portion 20 is blended with the outwardly bowed downwardly extending side members 23 by the complementary convex obtusely formed top radii 24 and 26. Side members take on a naturally occurring outward bow due to the nature of the material and the forming steps, particularly the forming of radii 24 and 26 and the radii 28 and 30 merging the side members 23 into planar, spring supporting base 32. Radii 28 and 30 are brought into close proximity, especially when the entire assembly is to be joined to backing plate 36.
When a load is applied downwardly to a completed spring array, perpendicular to base 32, each spring deflects and exerts an equal resistance force oriented opposite in direction to the applied load vector. During deflection, the central portions of side members 23 between the distal and proximal portions also displace laterally from each other.
As can be determined from the graph in FIG. 2, the amount of force required to achieve an initial displacement of the spring is large but begins to taper to a near constant force as deflection increases once the deflections are in the near constant force band where the slope of the force vs. deflection curve is essentially flat.
As compressive force is axially applied, the spring will exhibit a large increase in force per unit of deflection initially, smoothly transitioning to a large increase in deflection per unit of applied force, giving us a usable near-constant-force band spanning approximately 50% of the designed deflection range.
The axially applied force causes a decrease in spring height and causes a lateral deflection in the side members or legs of the spring. Any interference with these legs will alter the performance.
In an effort to minimize lateral displacement of the spring during deflection, the springs may also be constructed in accordance with a second embodiment as illustrated in FIG. 3. The side members of the first embodiment were modified as shown in such a way as to maintain symmetrical, balanced forces. The left-hand leg and right-hand leg are subdivided into four equal vertical sections with the outer two removed from the left-hand side and the center two removed from the right-hand side. The base of the legs are then moved toward each other until the left-hand center leg passes between the right-hand legs. The feet are then secured in this cross leg design. During deflection, each of the legs deform into a compound "S" shape, minimizing the outward deflection. The force/deflection curves are very similar to the basic design.
One side member of each spring 40 consists of a central leg 42 whose width is equal to slightly less than one-half the total width of spring 40. This minimal downsizing is necessary to provide for clearance between the interleaved legs. The other side member consists of two legs 44 and 46 which each have a width approximately equal to one-half the width of central leg 42. Top portion 62 may contain openings 50 for tool location or the passage of fluids or gas.
Interleaving is possible when the base 52 is allowed to overlap itself. The complex formed shape is obtained by performing three method steps. First, the spring is formed into its initial formed profile as shown in FIG. 4a. The base 52 is then secured via tooling holes 54 and base portions 56 and 58 brought together until they pass through each other, legs 42,44, and 46 overlapping base 52, forming a cross-over point 66. Base 52 is then secured to itself at points where it overlaps itself 60. For increased strength and stability, the legs 42, 44, and 46 do not directly join the top portion 62 but instead join a short transition sidemember 64, spanning the entire width. With this design, lateral displacement of the spring when fully displaced is reduced by 33-50%. The constancy of the spring force is slightly lower than is that of the first embodiment apparently because the complex deflection occurs over shorter length buckled side members rather than the longer ones of the first embodiment.
In the event that performance comparable to that of the first embodiment is required for more densely packed springs on smaller center-to-center distances, the split leg design of the second embodiment can be formed with each of the springs in the same non-interleaved fashion as the standard design of the first embodiment to yield a high density version as shown in FIG. 5. To achieve this, the right-hand and left-hand side members are divided vertically into 4 equal segments with allowance for clearance between intermeshing portions. The middle two segments are removed on the right-hand side while the outer two segments are removed from the left-hand side. The central leg portion 80 of the left-hand side is then allowed to intermesh between the two outer parallel legs 82 and 84 of the adjacent spring. Adjustments will need to be made in part geometry to compensate for the lower spring force due to reduced cross sectional area compared to the first embodiment. When compressed, the central legs 80 will interleave with the outer parallel legs 82 and 84 allowing adjacent springs to be formed as close together in the array as physically possible, while offering an uncompromised useful deflection range.
To increase the amount of resistance force, one can increase leg width or material thickness. However, increasing leg width may not be possible due to design constraints, and increasing thickness tends to detract from the desired performance characteristics. In such situations, a high performance embodiment, illustrated in FIG. 6, utilizing four legs instead of the normal two may be used. This requires a larger top member 92. The four side members 94 may either be identical in width or, alternatively, opposing side members 94 may be varied to obtain any desired force. When compressed, the four sides will bow in a fashion similar to compressing an inflated balloon. The base may be a series of butt joints 96 or may overlap as bases 98 and 100 overlap and overlie base 102.
Each individual spring of the present invention, for example as illustrated in FIGS. 1, 3, 4A, 4B, 5, 6 and 8, may also be described as comprising a spring-supporting base, upwardly extending side bands, each side band having a proximal end joined to the base by a concave transitional arc, mid-points of the concave arcs all lying in a first plane, each side band also having a distal end, and a top portion joined at a perimeter of the top portion by a convex transitional arc to a distal end of each side band, mid-points of the convex transitional arcs all lying in a second plane parallel to the first plane, such that each convex transitional arc is also parallel to the concave transitional arc of the same side band. The side bands and the top portion are all formed of generally planar flexible sheet material.
The disclosure of the present invention teaches both a spring structure for non-linear force versus deflection, and a folded sheet array of springs. For various applications, each may be separately and independently useful. Furthermore, these two can be synergistically combined. An array of these springs, as shown in FIGS. 1, 3 and 4, allows simultaneously a very dense array and a wide deflection range with near-constant force. Also, this structure for a non-linear spring is highly compatible with a printed-circuit-like construction for a dense array of springs. This synergism might be better appreciated by contrast with the prior art.
Prior art springs could not simultaneously achieve a dense array and near constant force over a wide deflection range. A printed circuit array of planar cantilever springs requires short levers to achieve high density and therefore cannot provide a wide deflection range with near-constant force. An array of Bellvelle washers can provide large density but only a narrow range of near constant force. A common tape measure contains a coiled metal tape which may be considered a spring with a constant tensile force over a very wide range of extension. This spring is incompatible with a dense array. Still other designs for buckling beam springs are not compatible with an array sheet structure and not compatible with fabrication like a printed circuit. By contrast, the two parts of the present invention synergistically achieve what prior art could not achieve.
A goal of the present invention is near constant force, and zero lateral motion and force. In other applications, the goal may be to enhance and control the variation in compressive force, and/or to enhance and control sideways motion and sideways force. This can be done by shaping the legs of the springs. During deflection, this could provide snap action, bistable motion or other types of response. Some versions might be valuable for keyboards or other applications. | A thin sheet of metal is patterned, folded, and joined to produce an array of compression springs, each of which exhibits constant force characteristics over a useful range of deflections to allow the array to apply nearly constant specified forces to closely spaced items which may be of varying size or height. As the springs are loaded from a relaxed state, the rate of force increase per unit of increased deflection is initially high, tapering off to nearly zero force increase with subsequent increases in deflection. This region of minimal force increase per unit of increased deflection (i.e. a "near constant force" band) extends over a useful range of deflections. The springs are self guiding and balanced, producing no lateral force on a perpendicularly applied load. | 5 |
FIELD OF THE INVENTION
[0001] The invention relates to induced pluripotent stem cells. More particularly, the invention relates the reprogramming of human umbilical cord tissue-derived cells (hUTC) into induced pluripotent stem (iPS) cells.
BACKGROUND OF THE INVENTION
[0002] Induced pluripotent stem (iPS) cells have generated interest for application in regenerative medicine, as they allow the generation of patient-specific progenitors in vitro having a potential value for cell therapy (Takahashi, K. and Yamanaka, S., Cell 126, 663-76 (2006)). However, in many instances an off-the-shelf approach would be desirable, such as for cell therapy of acute conditions or when the patient's somatic cells are altered as a consequence of a chronic disease or ageing.
[0003] Ectopic expression of pluripotency factors and oncogenes using integrative viral methods is sufficient to induce pluripotency in both mouse and human fibroblasts (Takahashi, K. and Yamanaka, S., Cell 126, 663-76 (2006); Takahashi, K. et al. Cell 131,861-72 (2007); Hochedlinger, K. and Plath, K., Development 136,509-23 (2009); Lowry, W. E. et al., Proc Natl Acad Sci USA 105, 2883-8 (2008)). However, this process is slow, inefficient and the permanent integration of the vectors into the genome limits the use of iPS cells for therapeutic applications (Takahashi, K. and Yamanaka, S., Cell 126, 663-76 (2006)). Further studies have shown that the age, origin, and cell type used has a deep impact on the reprogramming efficiency. Recently, it was shown that retroviral transduction of human keratinocytes resulted in reprogramming to pluripotency which was 100-fold more efficient and twice as fast when compared to fibroblasts. It was hypothesized that these differences could result from the endogenous expression of KLF4 and c-MYC in the starting keratinocyte population and/or the presence of a pool of undifferentiated progenitor cells presenting an epigenetic status more amenable to reprogramming (Lowry, W. E. et al., Proc Natl Acad Sci USA 105, 2883-8 (2008).). This latter hypothesis has been further supported by other studies in mouse. (Silva, J. et al., PLoS Bio 16, e253 (2008); and Eminli, S. et al., Stem Cells 26, 2467-74 (2008)). However, stem cells are usually rare and difficult to access and isolate in large amounts (e.g., neural stem cells) (Kim, J. B. et al., Cell 136, 411-9 (2009); Kim, J. B. et al., Nature 454, 646-50 (2008)).
[0004] Human umbilical cord tissue-derived iPS cells represent a viable supply of pluripotent cells for a number of applications. It is of particular interest to regenerative medicine because umbilical cord tissue is from an early developmental origin and is has been shown to possess multilineage differentiation potential. In addition, umbilical cord tissue is likely exempt from incorporated mutations when compared with juvenile or adult donor cells such as skin fibroblasts or keratinocytes.
SUMMARY OF THE INVENTION
[0005] We describe herein, an induced pluripotent stem cell prepared by reprogramming a human umbilical cord tissue-derived cell. The human umbilical cord tissue-derived cell is an isolated umbilical cord tissue cell isolated from human umbilical cord tissue substantially free of blood that is capable of self-renewal and expansion in culture, has the potential to differentiate into cells of other phenotypes, can undergo at least 40 doublings in culture, maintains a normal karyotype upon passaging, and has the following characteristics: expresses each of CD10, CD13, CD44, CD73, CD90, PDGFr-alpha, PD-L2, and HLA-A,B,C; does not express any of CD31, CD34, CD45, CD80, CD86, CD117, CD141, CD178, B7-H2, HLA-G, or HLA-DR,DP,DQ; and increased expression of a gene for each of interleukin 8; reticulon 1; and chemokine (C-X-C motif) ligand 3 relative to that of a human cell which is a fibroblast, a mesenchymal stem cell, or an iliac crest bone marrow cell. The human umbilical cord tissue-derived cell further has the following characteristics: secretes each of the factors MCP-1, MIP1beta, IL-6, IL-8, GCP-2, HGF, KGF, FGF, HB-EGF, BDNF, TPO, RANTES and TIMP1; and does not secrete any of the factors SDF-1alpha, TGF-beta2, ANG2, PDGFbb, MIP1a and VEGF.
BRIEF DESCRIPTION OF THE FIGURES
[0006] FIG. 1 . Morphology of human umbilical cord tissue-derived iPS cells, clone K1, obtained from transduction of hUTC with human OCT4, SOX2, KLF4, and c-MYC and shRNA to p53. Clones are shown on irradiated mouse embryonic fibroblast (MEF) feeder layer at passage 1.
[0007] FIG. 2 . Human umbilical cord tissue-derived iPS cells (clone K1) grown on MEF feeder layer and stained for alkaline phosphatase (4× magnification).
DETAILED DESCRIPTION OF THE INVENTION
[0008] We disclose herein, the reprogramming of human umbilical cord tissue-derived cells (hUTC) to pluripotency by retroviral transduction of four (OSKM) transcription factors with or without the downregulation of p53. Using the methods and compositions described herein, hUTC are reprogrammed to pluripotency by retroviral transduction with OCT4, SOX2, KLF4, and c-MYC. The resulting reprogrammed hUTC have the characteristics of induced pluripotent stem (iPS) cells.
[0009] In one embodiment, an induced pluripotent stem (iPS) cell is prepared from a human umbilical cord tissue-derived cell, referred to herein as a human umbilical cord tissue-derived iPS cell. The hUTC were reprogrammed by the forced expression of the reprogramming factors in the presence or absence of shRNA to p53. The reprogrammed cells were characterized for morphology, staining for alkaline phosphatase, expression of pluripotency markers, methylation of specific promoters, and expression of specific germ layer markers.
[0010] hUTC are a unique population of cells isolated from human umbilical cord tissue. The methods for isolating hUTC are described in U.S. Pat. No. 7,510,873, incorporated by reference herein in its entirety. Briefly, the method comprises (a) obtaining human umbilical cord tissue; (b) removing substantially all of the blood to yield a substantially blood-free umbilical cord tissue, (c) dissociating the tissue by mechanical or enzymatic treatment, or both, (d) resuspending the tissue in a culture medium, and (e) providing growth conditions which allow for the growth of a human umbilical cord tissue-derived cell capable of self-renewal and expansion in culture and having the potential to differentiate into cells of other phenotypes.
[0011] In preferred embodiments, the cells do not express telomerase (hTert). Accordingly, one embodiment the human umbilical cord tissue-derived cells that do not express telomerase (hTert) and that have one or more of the characteristics disclosed herein.
[0012] In one embodiment, the cells are umbilical cord tissue-derived cells which are isolated from human umbilical cord tissue substantially free of blood, are capable of self-renewal and expansion into culture, have the potential to differentiate into cells of other phenotypes, can undergo at least 40 doublings, and have the following characteristics: (a) express each of CD10, CD13, CD44, CD73, CD90, PDGFr-alpha, PD-L2 and HLA-A,B,C; (b) do not express any of CD31, CD34, CD45, CD80, CD86, CD 117, CD141, CD178, B7-H2, HLA-G, or HLA-DR,DP,DQ; and (c) increased expression of interleukin-8; reticulon 1; and chemokine receptor ligand (C-X-C motif) ligand 3, relative to that of a human cell which is a fibroblast, a mesenchymal stem cell, or an iliac crest bone marrow cell. In one embodiment, these umbilical cord derived cells also have one of more of the following characteristics: (a) secretion of each of the factor MCP-1, MIP1beta, IL-6, IL-8, GCP-2, HGF, KGF, FGF, HB-EGF, BDNF, TPO, RANTES, and TIMP1; and (b) no secretion of any of the factors SDF-1alpha TGF-beta2, ANG2, PDGFbb, MIP1a and VEGF. In another embodiment, these umbilical cord tissue-derived cells do not express hTERT or telomerase.
[0013] In another embodiment, the cells are umbilical cord tissue-derived cells which are isolated from human umbilical cord tissue substantially free of blood, are capable of self-renewal and expansion into culture, have the potential to differentiate into cells of other phenotypes, do not express CD117 and express telomerase or hTert. In yet another embodiment, the cells further do not express CD45. In an alternate embodiment, the cells further do not express any of CD31, CD34, CD80, CD86, CD141, CD178, B7-H2, HLA-G, or HLA-DR,DP,DQ. In another alternate embodiment, the cells further express each of CD10, CD13, CD44, CD73, CD90, PDGFr-alpha, PD-L2 and HLA-A,B,C. In yet another embodiment of the invention, the cells further can undergo at least 40 doublings. In yet another embodiment, the cells further show increased expression of interleukin-8; reticulon 1; and chemokine receptor ligand (C-X-C motif) ligand 3, relative to that of a human cell which is a fibroblast, a mesenchymal stem cell, or an iliac crest bone marrow cell. In yet another embodiment, the cells further have each of the following characteristics: (a) secretion of each of the factor MCP-1, MIP1beta, IL-6, IL-8, GCP-2, HGF, KGF, FGF, HB-EGF, BDNF, TPO, RANTES, and TIMP1 and (b) no secretion of any of the factors SDF-1alpha TGF-beta2, ANG2, PDGFbb, MIP1a and VEGF.
[0014] The hUTC were reprogrammed using viral reprogramming methods. In one embodiment, the hUTC were transfected with retroviruses individually carrying constitutively expressed human transcription factors OCT4, SOX2, KLF4, and c-MYC. Briefly, hUTC were plated on a 6-well plate, at 1×10 5 cells per well in hFib medium, and incubated for 6 hours at 5% CO 2 and 37° C. The four murine retroviral constructs (OCT4, SOX2, KLF4, and c-MYC) and an agent for increasing the efficiency of transfection were added to each well. After overnight incubation at 5% CO 2 and 37° C., this transduction step was repeated. After 24 hours, the medium was aspirated and fresh hFib medium was added. After another 48 hours, cells were harvested and plated on a 60-mm dish pre-seeded with mouse embryonic feeder (MEF) cells in hFib medium. After 48 hours, medium was replaced with hES medium. Cells were allowed to incubate for three to four weeks with hES medium replaced daily.
[0015] In another embodiment, hUTC were transfected with VSVg murine retroviruses individually carrying constitutively expressed human transcription factors OCT4, SOX2, KLF4, and c-MYC and p53-shRNA. The inhibition of p53 has been previously shown to enhance the reprogramming efficiency of specific cell types presumably by slowing down cell proliferation (Zhao Y et al., (2008) Cell Stem Cell 3: 475-479; Sarig, R., et al., J. Exp. Med. 207: 2127-2140 (2010)). Briefly, hUTC were plated in a 6-well plate, at 1×10 5 cells per well in Hayflick medium and incubated overnight at 5% CO 2 and 37° C. For viral transfections, transduction medium having the four VSVg murine retroviral constructs (OCT4, SOX2, KLF4, and c-MYC) and p53-shRNA and an agent for increasing the efficiency of transfection was prepared for each well. Medium was aspirated from the wells, transduction medium was added, and incubated overnight at 5% CO 2 and 37° C. This transduction step was repeated the following day and after overnight incubation, the transduction medium was replaced with Hayflick medium. Cells were allowed to incubate for another four days with Hayflick medium replaced every two days.
[0016] The transfected hUTC were then cultured and observed for the appearance of classical iPS cell morphology. Classical iPS cell morphology refers to the formation of tightly packed cell colonies that are refractive or “shiny” under light microscopy with very sharp and well-defined edges. Cells exhibiting classical iPS cell morphology were isolated, subcultured, and expanded to provide human umbilical cord tissue-derived iPS cells.
[0017] Several criteria are used to assess whether iPS cells are fully reprogrammed including morphology (as described above), staining for alkaline phosphatase, expression of pluripotency markers, methylation of specific promoters, and expression of specific germ layer markers. The expression of a key pluripotency factor, NANOG, and embryonic stem cell specific surface antigens (SSEA-3, SSEA-4, TRA1-60, TRA1-81) have been routinely used to identify fully reprogrammed human cells. At the functional level, iPS cells also demonstrate the ability to differentiate into lineages from all three embryonic germ layers.
[0018] The human umbilical cord tissue-derived iPS cell prepared by the methods described herein was characterized for pluripotency. These cells which display the classical iPS cell morphology, are capable of self-renewal, express the key pluripotency markers (TRA1-60, TRA1-81, SSEA3, SSEA4, and NANOG), demonstrate differentiation into lineage from three germ layers, and show normal karyotype.
[0019] Human umbilical cord tissue-derived iPS cells represent a good source of pluripotent cells for regenerative medicine. With this technology, it is now possible to generate pluripotent cells in large numbers. Another important benefit is the potential to obtain iPS cells from a tissue originating from an early developmental origin and from a tissue that is probably free from incorporated mutations relative to adult donor cells. These cells will be useful for comparisons among iPS cells derived from multiple tissues regarding the extent of the epigenetic reprogramming, differentiation ability, stability of the resulting lineages, and the risk of associated abnormalities.
[0020] The invention is further explained in the description that follows with reference to the drawings illustrating, by way of non-limiting examples, various embodiments of the invention.
EXAMPLES
Example 1
Reprogramming of hUTC into iPS Cells
[0021] hUTC obtained according to the methods described in U.S. Pat. No. 7,510,873, were transduced with murine retroviruses individually carrying constitutively expressed human transcription factors (OCT4, SOX2, KLF4, and c-MYC). hUTC were thawed and cultured for one passage before transduction. On day 1, hUTC were trypsinized and plated onto 6-well plates at 1×10 5 cells per well in 2 milliliters of hFib medium (DMEM (Invitrogen Corporation, Carlsbad, Calif., catalog number 11965-092) containing 10% fetal bovine serum (FBS) sold under the tradename BENCHMARK (Gemini Bio-products, West Sacramento, Calif., catalog number 100-106, vol/vol), 2 millimolar L-glutamine sold under the tradename GLUTAMAX (Invitrogen Corporation, catalog number 35050-061), 50 Units/millilter penicillin and 50 milligrams/milliliter streptomycin (Invitrogen Corporation, catalog number 15140-122) per well. Cells were incubated for 6 hours at 5% CO 2 and 37° C. Medium was aspirated to remove non-viable cells and 2 milliliters of fresh hFib medium was added. Retroviruses individually carrying OCT4, SOX2, KLF4 and c-MYC (each with an MOI of 5) and 10 microliters (200×) of an infection reagent sold under the tradename TRANSDUX (System Biosciences, Inc., Mountain View, Calif., catalog number LV850A-1) were added into each well, and mixed gently by swirling the plate. On day 2, the viral transduction step was repeated. On day 3, the transduction medium was removed, the cells washed, and the medium was replaced with 2 milliliters of hFib medium. On this same day, 1×10 5 mitomycin C-treated MEF cells were seeded onto 60-millimeter dishes (pre-coated with 0.1% gelatin (Millipore Corporation, Billerica, Mass., catalog number ES-006-B, wt/vol) and incubated overnight at 5% CO 2 and 37° C.
[0022] To monitor the formation of reprogrammed or iPS cell colonies, the transduced hUTC were harvested by trypsinization on day 4, resuspended in hES medium (DMEM/F12, Invitrogen Corporation, catalog number 11330-32) containing 20% knock-out serum (KSR, Invitrogen Corporation, catalog number 10828-028, vol/vol), 10 nanograms/millilter basic fibroblast growth factor (bFGF; R&D Systems, Inc., Minneapolis, Minn., catalog number 233-FB-025), 1 millimolar GLUTAMAX , 0.1 millimolar nonessential amino acids (Invitrogen Corporation, catalog number 11140-050), 0.1 millimolarM 2-mercaptoethanol (Sigma-Aldrich, St. Louis, Mo., catalog number M7522), 50 Units/milliliter penicillin and 50 milligrams/milliliter streptomycin(Invitrogen Corporation, catalog number 15140-122) and then plated on mouse embryonic fibroblast (MEF) feeder plate at a concentration of 1×10 6 cells per 60 millimeter dish. Cells were plated at different cell densities between 3×10 4 to 1×10 5 cells. On day 6, medium was aspirated and replaced with hES medium. Medium was changed with fresh hES medium daily for 3 to 4 weeks. The plates were checked daily to identify iPS cell colonies.
[0023] For reprogramming in the presence of shRNA to p53, hUTC were transduced with retroviral constructs specifically, VSVg murine retroviruses individually carrying constitutively expressed human transcription factors (OCT4, SOX2, KLF4, and c-MYC) and VSVg murine retrovirus containing p53-shRNA.
[0024] The murine retroviruses were produced using the 293-gp2 retrovirus packaging cells that were plated one day prior to transfection onto 6 centimeter dishes at a density of 3×10 6 cells per dish and incubated overnight at 5% CO 2 and 37° C. Each dish was then transfected with 3 micrograms pMX vector (Sox2, Oct4, cMyc, Klf4, or p53-shRNA vector, 1 microgram VSV-g and 16 microliters of a transfection agent sold under the tradename FUGENE HD (Roche Applied Bioscience, Indianapolis, Ind., catalog number 04709705001) according to the manufacturer's standard protocol. Viruses were then collected 48 hours after transfection and filtered through a 0.45micron filter prior to use.
[0025] hUTC were thawed and cultured for one passage before transduction. One day before transduction, hUTC were trypsinized and plated onto 2 wells of a 6-well plate at 1×10 5 cells per well in 2 milliliters of renal epithelial growth medium (REGM, Lonza Walkersville, Inc., Walkersville, Md.) per well. Cells were incubated overnight at 5% CO 2 and 37° C. On day 1, 2.5 milliliters of transduction medium was prepared for each well containing 500 microliters of each freshly-made virus and 4 nanograms/milliliter of polybrene. The culture medium was aspirated from the wells, the transduction medium was added, and was incubated overnight at 5% CO 2 and 37° C. On day 2, the viral transduction step was repeated. On day 3, the transduction medium was removed and replaced with REGM. Media changes were performed every 2 days until day 7.
[0026] To monitor the formation of reprogrammed or iPS cell colonies, the transduced hUTC were harvested by trypsinization, resuspended in culture medium sold under the tradename STEMEDIUM NUTRISTEM (Stemgent, Inc., Cambridge, Mass., catalog number 01-0005) supplemented with an additional 20 nanograms/milliliter of bFGF (iPS-Nu medium) or standard knockout serum replacement (KSR)-containing human ES medium with 20 nanograms/milliliter of bFGF (iPS-KSR medium), and then plated on a basement membrane matrix, sold under the tradename MATRIGEL (BD Biosciences, Chicago, Ill., catalog number 354277)-coated or mouse embryonic fibroblast (MEF) feeder plate at a concentration of 1×10 4 cells per well in 6-well plate. Medium was changed with fresh iPS medium every 2 days during the first week and daily during weeks 2 to 6. The plates were checked daily to identify iPS cell colonies.
[0027] Colonies exhibiting the ‘classic’ reprogrammed or iPS cell morphology were manually picked from MEF feeder plates and seeded onto a single well of a 12-well MEF feeder plate. Culture medium was changed daily. After 4-6 days, the colonies were manually picked from the 12-well plates and expanded into 6-well plates. Culture medium was changed daily and manually split 1:3 every 4-6 days. Cells from each well were frozen at various stages in using a freezing medium, sold under the tradename CRYOSTEM (Stemgent, Inc., catalog number 01-0013).
Results
[0028] Reprogramming of hUTC with the retroviruses expressing the four reprogramming factors resulted in reprogrammed colonies exhibing the iPS cell morphology. Reprogrammed colonies were manually picked and of these colonies, 12 were expanded and frozen. Human umbilical cord tissue-derived iPS cells obtained using the four reprogramming factors are denoted as FF followed by the colony number.
[0029] Reprogramming of hUTC with the retroviruses expressing the four reprogramming factors and shRNA to p53 resulted in reprogrammed colonies exhibing the iPS cell morphology. Twenty-five reprogrammed colonies were manually picked and of these colonies, 19 were expanded and frozen. Human umbilical cord tissue-dervied iPS cells obtained using the four reprogramming factors and p53 shRNA are denoted as N (originally maintained in STEMEDIUM NUTRISTEM-containing medium) followed by the colony number or as K (originally maintained in KSR-containing medium) followed by the colony number ( FIG. 1 ).
Example 2
Expression of Pluripotency Markers
[0030] The human umbilical cord tissue-derived iPS cells prepared in Example 1 were assessed for their expression of pluripotency markers by immunocytochemistry. Following fixation of the colonies in 4% paraformaldehyde, immunofluorescent staining for pluripotency markers was performed using the antibody reagents shown in Table 1(all antibodies were obtained from Stemgent, Inc.).
[0000]
TABLE 1
Marker
Primary Antibody
Secondary Antibody
TRA-1-81
Mouse anti-Human TRA-1-81
NA
Antibody, sold under the
tradename DYLIGHT 549,
catalog number 09-0082
TRA-1-60
Mouse anti-Human TRA-1-60
NA
Antibody, sold under the
tradename STAINALIVE
DYLIGHT 488, catalog
number 09-0068
SSEA-3
Anti-Human SSEA-3
Goat anti-Rat IgG +
Antibody, catalog
IgM Antibody, sold under
number 09-0014
the tradename CY 3,
catalog number 09-0038
SSEA-4
Anti-Human SSEA-4
Goat anti-Mouse IgG +
Antibody, catalog
IgM Antibody, sold under
number 09-0006
the tradename CY 3,
catalog number 09-0036
NANOG
Anti-Mouse/Human
Goat anti-Rabbit IgG
NANOG Antibody,
Antibody, sold under the
catalog number 09-0020
tradename CY 3, catalog
number 09-0037
Results
[0031] A representative human umbilical cord tissue-derived iPS cells clone, clone K1, was assessed for expression of pluripotency markers. Human umbilical cord tissue-derived iPS cells, clone K1, express the markers TRA1-60, TRA1-81, SSEA3, SSEA4, and NANOG. These markers were not detected in the parental hUTC. The expression of these markers indicates pluripotency of the human umbilical cord tissue-derived iPS cells.
Example 3
Methylation Analysis of Oct4, Nanog, and Sox2 Promoters
[0032] The human umbilical cord tissue-derived iPS cells prepared in Example 1, clone N1, were analyzed for the methylation status of the Oct4, Nanog, and Sox2 promoter regions using the bisulfite sequencing method and was performed by Seqwright, Inc. (Houston, Tex.). The bisulfite method is the most commonly used technique for identifying specific methylation patterns within a DNA sample. It consists of treating DNA with bisulfite, which converts unmethylated cytosines to uracil but does not change methylated cytosines. It is used both for loci-specific or genome-wide analyses.
[0033] Approximately 100 to 500 bp-long promoter regions of of Oct4, Nanog, and Sox2 were examined for methylation patterns. DNA (see Table 2) were prepared using the DNA extraction kit sold under the tradename DNEASY (Qiagen, Inc., Valencia, Calif., catalog number 69506) and were sent to Seqwright, Inc. for analysis.
[0000]
TABLE 2
Sample ID
Sample description
1
parental hUTC
2
hUTC N1 p12
Results:
[0034] Table 3 summarizes the results obtained from the analysis of the promoter regions. Within the regions that were tested, no methylation sites were detected within the Sox2 promoter. There were 5 methylation sites detected for the Oct4 promoter and 2 methylation sites for the Nanog promoter. Relative to the parental cells, the umbilical cord tissue-derived iPS cells showed a change in the methylation pattern in 1 of the 5 sites within the Oct4 promoter and in 1 of the 2 sites for the Nanog promoter. This change in methylation pattern is a characteristic of iPS cells.
[0000]
TABLE 3
Total
methylation sites
Total
Total
Promoter
Bp
found in the
changed
unchanged
region
examined
region
sites
sites
Oct4 promoter
~520 bp
5
1
4
Nanog promoter
~100 bp
2
1
1
Sox2 promoter
~550 bp
0
—
—
Example 4
Alkaline Phosphatase Staining
[0035] The pluripotency of the human umbilical cord tissue-derived iPS cells prepared in Example 1, clone K1, was also assessed by alkaline phosphatase staining (AP) and was performed using an alkaline phosphatase detection kit (Millipore Corporation, Billerica, Mass., catalog number SCR004). Human umbilical cord tissue-derived iPS cells were plated onto MEF-seeded 24-well plates and maintained in a 37° C. incubator. After 3-5 days, culture media was aspirated from the wells and the cells were fixed using 4% paraformaldehyde for 1-2 minutes. The fixative was removed and the cells were washed with 1 milliliter of 1× rinse buffer. Afterwards, rinse buffer was replaced with 0.5 milliliter of staining reagent mix and incubated at room temperature for 15 minute. The staining reagent was prepared by mixing the kit components fast red violet (FRV) and naphthol AS-BI phosphate solution with water in a 2:1:1 ratio (FRV:Naphthol:water) in an aluminum foil-covered tube. The staining reagent was removed and cells were washed once with 1 milliliter of 1× rinse buffer and then incubated in 0.5 milliliter of PBS. Images of stained cells were captured with a photomicroscope. Cells exhibiting AP activity appear purple.
Results
[0036] As shown in FIG. 2 , human umbilical cord tissue-derived iPS cells, clone K1, exhibited positive alkaline phosphatase staining that is indicative of the pluripotent state.
Example 5
Differentiation into Lineages of Three Germ Layers
[0037] The differentiation capacity of the human umbilical cord tissue-derived iPS cells prepared in Example 1, clone FF44, into ectodermal, mesodermal, and endodermal lineages was evaluated by staining for markers specific to the three germ layers.
[0038] Human umbilical cord tissue-derived iPS cells were seeded onto MATRIGEL basement membrane matrix-coated plates in MEF conditioned medium for seven days. Immunocytochemistry of the differentiated human umbilical cord tissue-derived iPS cells was performed by fixing the cells in 4% paraformaldehyde for 10 minutes at room temperature. Fixed cells were washed twice with phosphate-buffered saline (PBS), and incubated at room temperature for one hour in a PBS+3% fetal bovine serum solution. Afterwards, cells were washed twice with a washing buffer sold under the tradename BD PERM/WASH (BD Biosciences, Chicago, Ill., catalog number SI-2091KZ). The cells were incubated in the specific antibody (Table 4) in BD PERM/WASH overnight at 4° C. Cells were washed five times with BD PERM/WASH and then incubated with the secondary antibody for 1.5-2 hours at room temperature in the dark. After washing the cells with PBS, cell nuclei were visualized by incubating the cells in 0.1-1 microgram/milliliter API (DNA stain, 1:10000 diluted) for 2 min. After a final wash with PBS, the cells were processed for immunofluorescence microscopy.
[0000]
TABLE 4
Germ
Layer
Primary Antibody
Secondary Antibody
Ectoderm
Nestin (Stemgent, Inc.,
Goat anti-mouse IgG antibody,
catalog number 09-0045)
sold under the tradename
ALEXA FLUOR 680,
(Invitrogen Corporation,
Carlsbad, CA, catalog
number A20983)
Mesoderm
Alpha-smooth muscle
Goat anti-mouse IgG antibody,
actin (SMA; Sigma-
sold under the tradename
Aldrich, St. Louis, MO,
ALEXA FLUOR 680,
catalog number
(Invitrogen Corporation,
SAB1400414)
catalog number A20983)
Endoderm
Alpha-fetoprotein1 (AFP1;
FITC Goat anti-rabbit IgG
Dako North America, Inc.,
(Abcam, Cambridge, MA,
Carpinteria, CA, catalog
catalog number Ab6717)
number A0008)
Results
[0039] The human umbilical cord tissue-derived iPS cells were stained with antibodies to nestin, alpha-smooth muscle actin (alpha-SMA), and alpha-fetoprotein 1(AFP1) to evaluate differentiation into ectodermal, mesodermal, and endodermal lineages, respectively. The human umbilical cord tissue-derived iPS cell, clone K1, expressed these germ layer markers indicating that these cells have the capacity to differentiate into cells from these germ layers.
Summary
[0040] Overall,we have shown the generation of human umbilical cord tissue-derived iPS cells by overexpression of human transcription factors using integrating (viral) methods. These results demonstrate that human umbilical cord tissue-derived iPS cells express the pluripotency markers TRA1-60, TRA1-81, SSEA3, S SEA4, and NANOG and exhibit positive alkaline phosphatase staining Upon examination of a 100-500 base pair region of the Oct4 promoter, the human umbilical cord tissue-derived iPS cells show a change in methylation on 1 out of the 5 methylation sites examined compared with the parental hUTC line. For the Nanog promoter, the human umbilical cord tissue-derived iPS cells show a change in methylation on 1 out of the 2 methylation sites examined compared with the parental hUTC line.
[0041] These cells also display protein markers of cells derived from ectodermal, mesodermal, and endodermal lineages showing the differentiation potential of these reprogrammed cells.
[0042] While the invention has been described and illustrated by reference to particular embodiments and examples, those of ordinary skill in the art will appreciate that the invention lends itself to variations not necessarily illustrated herein. For this reason, then, reference should be made solely to the appended claims for purposes of determining the true scope of the invention. | We have disclosed an induced pluripotent stem cell and the method of preparing the induced pluripotent stem cell from a human umbilical cord tissue-derived cell. More particularly, we have disclosed a human umbilical cord tissue-derived iPS cell which may be differentiated into cells of ectoderm, mesoderm, and endoderm lineages. | 2 |
FIELD OF THE INVENTION
[0001] The detection of fissionable materials (e.g. U, Pu, Th) within cargo, subsurface soil, waste and the like is achieved by probing with a photon beam able to cause emission of some fission-derived neutrons and providing selected means to detect such neutron emissions.
BACKGROUND AND PRIOR ART
[0002] Detection of illicit fissionable materials remains one of the greatest technical challenges in the field of nuclear counter-terrorism. These materials can be the main ingredients of a dirty bomb or, even worse, an atomic bomb or improvised nuclear device. Although plutonium (Pu) is a very worrisome material, it emits neutrons from spontaneous fission in its natural state and the neutrons (despite their low abundance) along with some gamma rays (from alpha decay) can be utilized for determining its presence. Other fissionable materials are much more difficult to detect.
[0003] Enriched uranium is very difficult to detect with current technology because it emits practically no radiation in its natural state due to its long half-life. The very few gamma rays that it does emit are low in energy and can be easily shielded by a small thickness of lead. Thus, the detection of enriched uranium (mainly 235 U) is not practical using passive radiation detectors, such as those deployed for other potential dirty bomb materials such as 137 Cs and 60 Co, which are strong gamma-ray emitters.
[0004] The detection of fissionable materials, such as 239 Pu and 235 U, by “active interrogation” techniques has been done for many years. These techniques have been applied, for instance, in the detection and quantification of fissionable materials in laboratory waste in connection with nuclear fuel processing. The most common active interrogation methodology is to use neutrons as the “probe” and to detect all of the radiations (neutrons and gamma rays) from induced fission. The main challenge to this approach is distinguishing the neutrons used as the probe from the radiation created by the ensuing fission process. Techniques that have been deployed include: using a pulsed neutron source and detecting the resulting radiation in-between the pulsed sources of neutrons; using thermal neutrons as the probe and detecting only fast neutrons from the induced fission; and using several radiation detectors in time-coincidence, taking advantage of the fact that only fission produces a multiplicity of simultaneous emissions. All of these techniques require sophisticated and complicated timing electronics for proper operation. Generally these techniques detect only the less abundant delayed neutrons and not the abundant prompt neutrons.
[0005] Another technological approach for “active interrogation” involves using high-energy photons as the probe and detecting the resulting radiation from fission using conventional radiation detectors such as gas counters or scintillators. This technique has not been used commonly because of the inability to suppress the influence of the probing photons on the conventional radiation detectors. The intensity of the probing photons is generally so high that it saturates the detectors and prevents them from detecting the desired resulting radiation from fission.
[0006] The following references are typical of such prior techniques.
[0007] U.S. Pat. No. 5,495,106, Feb. 27, 1996, G. F. Mastny.
[0008] Nuclear Science and Engineering, Vol. 73, p. 153-163 (1980), J. T. Caldwell et al.
[0009] Physical Review C., Vol. 21., No. 4. p. 1215-1231 (1980), J. T. Caldwell et al.
[0010] There is presently a need for an apparatus and method in which continuous inspection of targets is possible for detection of fissionable materials. Further, there is a need for an apparatus and method which allows for immediate detection of fission induced by the photon beam.
SUMMARY OF THE INVENTION
[0011] The invention includes an apparatus for detection of fissionable material in cargo, waste, subsurface soil and like targets comprising: a photon source selected to provide a photon beam able to penetrate the target, and able to cause emission of neutrons substantially only from fissionable material to be detected; detection means including at least one neutron detector selected and positioned to be substantially unaffected by the photon beam and able to detect, throughout said emission period, fission-derived neutrons; and, means to read each detector thereby to determine the presence of fissionable material.
[0012] The invention further includes a method of detecting fissionable material in various targets, comprising: penetrating the target with a photon beam selected to cause emission of neutrons from fissionable material to be detected over an appropriate period; detecting the resulting fission-derived neutrons throughout said emission period with selected detector means; and, reading the detector means thereby to determine the presence of fissionable material.
[0013] The photon beam energy and intensity and number of beams is selected to provide desired sensitivity for detection of the fissionable material. The detection system is selected to function while the photon beam is “ON” and throughout an appropriate neutron emission period.
DETAILED DESCRIPTION
[0014] The present invention involves an alternative technique that is very suitable for the detection of illicit fissionable materials such as 239 Pu and 235 U. This technique is a special application of the conventional “photon in, neutron out”, i.e. (y, n), approach. This specialized approach invokes conditions and selections relating to both the photon probe and the detector technology.
[0015] The Detector Technology
[0016] The interrogating photon beam would normally create havoc with conventional neutron (or gamma) detectors that are needed to detect the neutrons from the fission event. The intensity of the beam would normally render these detectors inoperative due to electronic saturation. However, there exists a relatively new class of radiation detectors that are now referred to as superheated droplet-type detectors and superheated droplet (emulsion) detectors and superheated droplet (gel) detectors being two embodiments of this class of detectors. The latter are often referred to as “bubble detectors”. For example, see Bubble Detector Patents: U.S. Pat. No. 4,613,758 and No. 5,105,088, by H. Ing et al. Superheated Droplet Detector Patents: U.S. Pat. No. 4,143,274 and No. 4,350,607 by Robert E. Apfel.
[0017] In these detectors, droplets are dispersed in suitable suspending media which are unaffected by the superheat temperature. Where the suspending media are liquid (e.g. emulsion) the resulting bubbles are free to move and coalesce (and sensitivity is reduced). Where the media are solidified (e.g. gel) the resulting bubbles are constrained and can be detected individually (i.e. improved sensitivity). When used herein “superheated droplet-type detector” is meant to include both emulsion and gel types.
[0018] The unique feature of such detectors and particularly bubble-type detectors is their high sensitivity to neutrons and lack of sensitivity to gamma radiation. This property is one of the main reasons why bubble detectors are deployed in medical facilities for measuring unwanted neutrons from radiation therapy treatments using Bremsstrahlung beams. It is this same property that makes the bubble detector highly suitable for detecting the neutrons produced by an interrogating photon beam.
[0019] A superheated droplet technology, for example, can be used to detect the neutrons from fission induced by a selected photon beam. By its intrinsic insensitivity to gamma radiation, the performance of the superheated droplet-type detector will not be adversely affected by the interrogating beam that would normally create havoc in other types of detectors. This means that the detector can be left “on”, even when the photon beam is interrogating the target, thereby eliminating the need for sophisticated timing electronics. Furthermore, since the majority of fission-related neutrons are produced essentially instantaneously when the fissionable material is interrogated by the photon beam, the fact that the detector can be “on” while the interrogation occurs drastically increases both the duty cycle and the sensitivity of this detection method as compared to other active interrogation techniques. Additionally, in order to optimize the response of the detector to neutrons from fission, the energy threshold of the detector can be adjusted by controlling the temperature, pressure, or chemical formulation of the superheated droplet detector liquid. The superheated droplet detector makes for a sensitive, simple and inexpensive neutron detector perfectly suited for this application. Detectors in a wide range of sizes and configurations can be made so that even tiny amounts of fissionable material can be detected rapidly. When neutrons are produced by the interrogating beam on a sample under examination, bubbles suddenly form in the gel medium of the bubble detector. The formation of these bubbles can be detected by a wide range of techniques, including but not limited to: optical techniques, acoustic techniques, light-scattering techniques with optical reading, imaging, electrical conductivity techniques, sound propagation, etc. Recompression of the bubbles into superheated liquid droplets (so that the detector can be re-used) can be achieved through a variety of techniques, including but not limited to: mechanical recompression, hydraulic recompression, gas-driven recompression, etc. The detector's response to neutrons as a function of temperature can be controlled through appropriate environmental enclosures or through temperature compensation techniques, including but not limited to, controlling the pressure of the detector medium to ensure a consistent degree of superheat in the detector liquid. Am array of detectors is used for the purpose of inspecting objects such as, for example, cargo containers, rail cars or the like. The detectors can be assembled in a “portal monitor” fashion (i.e. detectors on either side of a road or track, with several detectors arranged side by side, with perhaps additional rows of detectors stacked above). The accelerator can also be positioned in several locations depending on the environment and specific application. One such application can involve positioning the accelerator in the road pointing skyward. Alternatively, the accelerator can be located just prior to the detectors and oriented with the beam approximately parallel with the ground or tilted upward (so that the container is interrogated from the side). It is less desirable for the interrogating beam to be pointed towards the ground as this may create significant backscattering. Further, it is undesirable to have the interrogating beam pointing directly at the detectors, since this creates an unnecessarily harsh operating environment for the detector electronics.
[0020] Photon Probe Condition
[0021] Essentially all materials that are not fissionable have (y, n) thresholds higher than 6 MeV, with the exception of D, Be, 13 C, 17 O, 149 Sm and 151 Sm. Of these, D and Be are controlled substances and their presence is also of interest in counter-terrorism applications. The isotopes of 13 C and 17 O occur in low abundance in nature and do not pose a serious problem in terms of the proposed approach. Sm is a rare element and not commonly found in normal everyday materials. The fissionable elements 239 Pu and 235 U have (y, n) thresholds of 5.65 MeV and 5.30 MeV respectively (other fissionable isotopes have thresholds of comparable energies). By keeping the energy of the interrogating photons below about 6 MeV (or slightly above depending on the optimum ratio of signal to interference activity), neutron production will essentially only occur in fissionable isotopes. Such photon beams are easily produced by small accelerators (e.g. linear accelerators or “linacs”) where accelerated electrons impinge on a target (of high Z such as tungsten) to produce a bremsstrahlung photon spectrum extending to the energy of interest. In fact, by adjusting the energy of the accelerator one can (if desired) induce fission events over a particular photon energy range (e.g. about 5 MeV to 6 MeV) so that the beam can be “tailored” to investigate the presence of fissionable material. The functional definition of the 5-6 MeV energy range is the energy threshold above which fission neutrons will be produced by the fissionable materials of interest but below the energy threshold where other materials will start producing any significant number of neutrons when interrogated by the photon beam. One or more interrogating photon beams with the same or different photon energy end-points can be considered. More than one photon beam with the same end-point will increase the detection sensitivity of the overall detection system. The use of more than one photon beam with different end-points can improve the specificity for detection of specific fissionable material (see Example 2).
[0022] A linac is a sealed tube under vacuum consisting of a source of low-energy electrons at one end and a target made of high Z material (e.g. tungsten) at the other. In between are magnetic focusing lenses designed to keep the electrons geometrically confined so that they will strike the target at the far end. The in-between section is also designed to be a wave guide which allows “traveling waves” to propagate along its length. These waves are generated by “klystrons” which are generally located at the source end of the linac. The low-energy electronic source can be of different types, the simplest being the filament type. A wire is heated and electrons are “boiled off” in relation to the operating temperature.
[0023] The filament and some electromagnetic focusing components are typically sold as a single unit called an “electron gun”. The electron gun produces low energy electrons out of its nozzle when a voltage is applied (to heat up the filament). The low energy electrons are picked up by the traveling wave and gain energy as they travel towards the target. The final energy of these electrons is determined by the strength of the traveling wave and defines the operating voltage of the linac (e.g. 5 MeV, 6 MeV, etc.).
[0024] The remote operation of a linac can be achieved by voltage wires to the electronic source or the klystron extending from the linac to a remote point of operation. Conventional means to actuate the linac on or off by controlling power to the electronic source is known via the voltage to the filament or voltage to the electromagnetic lenses of the electron gun, i.e. the field lines direct the electrons away from the exit orifice.
[0025] Remote operation of the bubble detector can be as simple as remotely controlling a mechanical piston via a variety of means including the use of a reversible stepping motor to drive the piston.
[0026] Bubble detectors contain minute superheated droplets of low-boiling point liquid dispersed in a gel. When at atmospheric pressure, the bubble detector emulsion requires no power for operation. Neutrons are detected because of the stored mechanical energy in the superheated droplets. Upon detection of a neutron, the superheated droplet changes state immediately to a vapour bubble. The ˜300-fold change in volume allows one to “see” the result of neutron detection. To operate a bubble detector remotely, one must have a way of “seeing” these bubbles remotely. This can be achieved in many ways, including optical techniques, acoustic techniques, light-scattering techniques with optical reading, imaging, electrical conductivity techniques, sound propagation etc. The electronic signal produced by any of these techniques can be transmitted remotely and read from a distance. For a bubble detector to be insensitive to radiation (i.e. to keep the detector inactive) a certain mechanical pressure must be applied to the gel emulsion to reduce or negate the superheated state. This can be done in many ways. One example, as mentioned above, involves using a mechanical piston driving a liquid as a working fluid. When the piston is activated, the working fluid pushes against the emulsion, exerting the required pressure to keep the bubble detector in its insensitive state. By deactivating the piston, no pressure is exerted by the working fluid and the detector is ready to detect neutron radiation.
EXAMPLE 1
[0027] For detection of fissionable material concealed in a vehicle a linac can be positioned just below the surface of the road at a vehicle check point. Optionally, the linac can be buried vertically so that the photon beam emerges primarily in the upward direction. Small linacs that have (selectable) operating voltages that can produce electrons up to 9 MeV are readily available commercially (e.g. Varian Medical Systems, Linac Systems).
[0028] Large neutron detectors (up to several meters high by 1 m wide and 0.5 m thick) that are constructed from a single or an assembly of superheated droplet-type radiation detectors can be placed on the side of the road at the check point in conventional “portal monitor” configurations. The detector(s) can be turned on by remote control when inspection of vehicles is to be performed and left on until inspection is no longer desired. The interrogation of a specific vehicle by irradiating it with a photon beam from the linac will not affect the droplet-type detector(s) response.
[0029] When a vehicle at the check point is to be interrogated for the presence of fissionable material, the linac is turned on for a short period of time (e.g. 5 to 500 seconds). High energy photons from the linac penetrate the vehicle bottom to impinge any hidden fissionable material inside. In interacting with fissionable material, the photons will release neutrons that will be detected by the droplet-type detector(s) located beside the vehicle. When the electron beam of the linac is kept below about 6 MeV, neutrons will be produced only by Pu and U (and a few other isotopes of minor importance as discussed above). The presence of bubbles in the detector(s) from neutrons can be used as an indicator of the presence of the fissionable materials. Once bubbles are detected, the detector(s) can be re-set by use of external pressure as normally done in the deployment of droplet-type detector technology.
EXAMPLE 2
[0030] For greater improvement to detection sensitivity two linacs can be used for the interrogation with one linac capable of operating at about 6 MeV while the other linac is capable of operating at about 5 MeV. In this configuration, two irradiations occur sequentially for the same vehicle or object being inspected. Thus, the neutron signal produced by the 6 MeV linac minus the neutron signal from the 5 MeV linac will produce a measure of neutrons produced by the (V, n) reaction for photons between 5 MeV and 6 MeV. This method can provide a signature that is unique to fissionable materials and in particular to Pu and U. | An apparatus and method for the detection of fissionable materials (e.g. uranium and plutonium) in cargo, vehicles, soil, waste, etc. utilizing a penetrating photon beam causing emission of neutrons from such materials. The neutrons are detected by selected detectors able to function throughout an appropriate test and emission period. Suitable detectors are of the super-heated droplet type. The photon energy, beam intensity and direction, number of beams, emission period and detector arrangement are chosen to give the desired sensitivity for the fissionable elements of concern. | 6 |
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The present invention relates to a method for monitoring the manufacture of objects consisting of multiple material layers, such method being applicable, for example, in the production of preformed parts consisting of multiple layers of a material or of wires.
(2) Description of Related Art Including Information Disclosure Under 37 C.F.R. 1.97 and 1.98
There are numerous applications in which parts are produced on an industrial scale from multiple individual layers by successively layering the individual layers or by winding the layers around a winding core, respectively. For example, electric coils are wound from wires and thus successively built layer for layer, rotor blades for wind energy plants in part are also manufactured by winding individual layers of a suitable material onto a basic frame. In all methods, the aim is to obtain, at the end of the manufacturing process, an object having a desired three-dimensional design.
When manufacturing rotor blades for wind energy plants, for example, the proceedings are such that individual layers of a material are wound onto a basic frame, wherein these layers, for example, may consist of resin-soaked fiber-reinforced mats of synthetic material, which, after hardening of the resin, result in a very sturdy preformed body. Thereby, the glass fiber mats are provided on large drums, from which they are reeled off in the course of the production in order to be wound onto the basic frame as individual layers, such that, put in an illustrative manner, the construction is performed similar to applying a plaster bandage. It is important for the safety of the final element that a required minimum material thickness is maintained everywhere at the element, such that the stability of the finished rotor blade is guaranteed.
In the production of electric coils, thus, the winding of the coil wire, the correct construction of the individual layers then is of particular importance, when a high electric voltage drops along the coil wire. Then, with a faulty winding, a voltage difference may occur between two adjacent wire pieces, which is so high that the break-through voltage of the insulation is exceeded, due to which the coil is destroyed when in use. What is important here is, on the one hand, that per applied winding layer there is no deviation from a nominal thickness of the winding layer, thus, this thickness is not exceeded when, for example, two layers cross each other due to faulty winding. On the other hand, also the exact geometrical positioning of the individual wire is of interest in order to prevent the above-described case of the destruction of the coil. In particular, coils are also applied for creating high, precisely-defined magnetic fields in order to enclose, for example, gas plasma within a vacuum by means of the magnetic field created by means of the coils. In such cases, the individual windings of the coils have complicated geometrical shapes, thus, then have to be wound according to an exactly calculated scheme, such that in this utilization case not only the total material thickness of a finished wound coil is of interest, but also the geometrical arrangement of the individual windings, their winding sequence, respectively, is of interest.
A further example, in which products are manufactured on an industrial scale by means of winding techniques, is the production of tires. When building automobile tires, individual rubber layers are wound onto a drum-like carrier, by which successively the finished raw tire is created, which tire may also consist of multiple different rubber compounds. Thereby, air bubbles may form between the individual rubber layers during the winding process; by process faults, for example, when supplying rubber, it may happen that the material thickness of the finished tire locally is too low or too high. A finished produced tire must have a defined local material thickness, thus, have a cross-section following a predetermined profile. With too low material thickness, a tire blow-out may occur; if the material thickness locally is too high, this may lead to undesired running characteristics of the tire, such as, for example, imbalance or radial run-out. In order to prevent the safety risks concomitant with tires manufactured not according to standards, it must be ensured that the tire's cross-section follows the predetermined profile over the entire circumference of the tire.
Testing industrially-made parts, which are manufactured in a laminate or winding technology, according to the state of the art takes place after manufacturing. Thereby, the finished part is examined in respect to its inner construction. To this end, known non-destructive testing procedures, such as, for example, the ultrasound technology or X-raying by means of computer-assisted tomography, are applied.
A huge disadvantage consists in that the testing effort and the expenditure connected thereto, in particular when applying the computer-assisted tomography, are very high and that the test object is examined only after completion, thus, at a point in time when the total manufacturing costs already have occurred. There are also technological limits to the post-finishing testing method, for example, in the case of examination of a coil, it is principally impossible to conclude, after the finishing of the latter, by an imaging method the sequence in which the individual windings have been applied. Also, in part the local resolution, by which a finished object can be reconstructed, is too small to be able to localize small flaws within a compact three-dimensional object.
In particular with automobile tires, there is the problem that it is difficult to discern inclusions within the rubber layers, as in X-rays they show only a very limited contrast difference to the rubber material surrounding them.
BRIEF SUMMARY OF THE INVENTION
The object of the present invention consist in providing a method and a device for monitoring the manufacture of an object consisting of multiple material layers, by which the manufacture of such object can be monitored more precisely and efficiently.
This object is solved by a method according to claim 1 and by a device according to claim 10 .
The present invention is founded upon the recognition that the manufacture of an object consisting of multiple material layers successively being layered one upon the other can be monitored in that after the application of each layer a height profile of a circumference of the object is established, such that after the application of each material layer a comparison with a reference information can be used for evaluating whether the preceding production step has given a result enabling the conclusion that the material layer has been applied faultlessly. Thereby, the substantial advantage of the inventive method consists in that the spatial construction of the object, the tested part, respectively, is not sensed and tested after manufacture, but that, however, it is tested during manufacturing itself whether each individual layer has been applied correctly, such that, starting from the first layer, a 3D model of the body to be built can be made, in which model the material thickness added by a material layer is documented at any position of the surface of the object. Thereby, the location-dependent total material thickness results as a local sum of the layer thicknesses respectively applied.
The inventive method is particularly advantageous in that, by monitoring the product creation process, mistakes may be recognized which, for technological reasons, could not be recognized with the prior non-destructive testing methods at the finished object, as the testing method presented here, contrary to the prior applied methods, does not serve for examining a finished product for compliance with the requested guidelines (in particular the local thickness or a sequence of layers, or wires, respectively), but rather for monitoring, controlling, respectively, the construction itself and thereby improving the quota for the delivery of parts with an acceptable quality level.
From the knowledge of the thickness of individual layers (which may also consist of different materials, as, for example, mats from rubber, glass fiber and synthetic material, or metal foils) and from the detection of the 3D shape of an object after the application of every individual layer, for example, conclusions can be drawn in respect to air inclusions or also to the faulty positioning of an individual layer, when, for example, the measured local total thickness does not correspond to the sum of the (possibly measured beforehand, or known) thickness of the individual layers.
According to an embodiment example of the present invention, the production of a tire is monitored in accordance with the invention, wherein the tire is manufactured by winding multiple layers of rubber onto a cylindrical carrier. By the inventive method now an air inclusion between individual layers can be detected, which, for example, shows as a local thickness increase. The particular advantage therein consists in that an air inclusion, which is difficult to substantiate by means of the conventional testing methods after the completed production of the tire, can be proven very easily, wherein an additional advantage consists in that, depending on the severity of a recognized fault, the production may already be terminated before the actual end thereof, in order to thus save material.
In a further embodiment example of the present invention, the method according to the invention for monitoring the manufacture of an object is used for determining the end of a production process based on winding. To this aim, after each winding procedure, the distance of the surface of the object to be produced to a fixedly established sensor is determined, wherein the object is manufactured by winding several layers of a material around a cylindrical object carrier. When the distance of the surface of the object to the sensor drops below a certain minimum measurement, then the production process is terminated, i.e., no further layers of the material will be wound onto the object. This offers the huge advantage that, even if the material to be would is subjected to an unpredictable thickness alteration, an element can be created having a determinable local material thickness, wherein the local material thickness does not depend on the number of winding cycles, as this is the case otherwise.
A further advantage of the method according to the invention is that a sensor technology can be used for monitoring the manufacture of an object that rotates during manufacture, which is extremely cost-efficient and technologically inexpensive. So, it suffices in the above-described method, for example, to record a one-dimensional height profile, for example, by a light-section procedure, as the object to be produced continuously passes beneath the sensor, such that by combination of the angle of rotation of the object to be wound with the one-dimensional recording of a height profile, a complete two-dimensional image of the height profile on the surface of the object to be produced can be reconstructed.
It is a further advantage of the present invention that any other kind of creating a height profile of the objects to be monitored is possible; in particular, also methods can be applied which directly can measure a two-dimensional height profile, such as, for example, strip-projection methods or capacitive measuring methods, wherein the capacity of a surface to a given reference surface is measured, wherein the measured capacity depends on the relative distance of the two surfaces to each other.
In a further embodiment example of the present invention, the production of an electrical coil is monitored according to the invention, i.e. after each application of a winding layer, a surface height profile of the coil is created, wherein, when winding a coil, not only the local material thickness may be a substantial criterion, but also the sequence and the geometric orientation, in which the individual windings are brought onto the winding core. In that by the inventive method an examination of the geometry is performed after every individual winding layer, it is also possible to detect faults in the sequence of the winding, which principally is not possible with testing methods based on the examination of the finished wound coil.
The inventive method is not limited to objects which are created by winding layers of a material or by winding wires, however, it may also be applied to bodies and objects which are created by successive application of discrete layers (as, for example, glass fiber mats) of predetermined shape and thickness onto a carrier, as it is the case, for example, in the production of wings of aircrafts. Thereby, each individual layer may have a different shape and optionally also a different local thickness.
In a further embodiment example according to the invention, thus, the construction of a planar body, which is formed by laminating several layers of resin-soaked glass fiber mats, is monitored. Thereby, the height profile of the surface of the body is measured after the application of each individual layer, and the correct application of the layer is compared to a height information expected due to the local layer thickness, is examined, respectively. Thereby, for determining the height information, a method is employed which can produce a two-dimensional height profile of an object to be examined. Thus, after each production step, a complete three-dimensional surface of the object to be examined is reconstructed in that for each point of the surface of the object, the distance to a given reference point is determined. Thereby, it is possible, at the one hand, to apply a one-dimensional light-section procedure, in which height information solely is created along a measuring line, wherein the measuring line must be moved over the entire object to be examined in order to obtain a complete two-dimensional height profile. On the other hand, here, too, the strip-projection procedure may be applied, which directly delivers a two-dimensional height information.
In a further embodiment example of the present invention, the method is modified such that after the determination of the height profile of a basic area, thus, the surface on which the first layer of a layer material is provided, solely the height profile, after applying a final layer, is determined afresh. If one can proceed from the assumption that the basic area is not mechanically deformed during the production process, in this manner the achievement of an intended desired material thickness of the produced object can be examined. If solely the material thickness of the finished product is crucial, according to the invention an examination can be performed in an advantageous manner, wherein the testing expenditure can be substantially reduced, as in accordance with the invention merely two height profiles have to be recorded and evaluated.
In a further form of embodiment of the present invention, during production by the inventive method, it is evaluated whether the basic area, upon which the first material layer is applied, deforms due to forces effecting thereon during production. However, this is difficult to determine by test methods after the manufacture of the finished objects, when the basic body having the basic area, remains in the object after finishing of the object, as this is the case, for example, when manufacturing rotor blades. Thereby, according to the invention a height profile is established after the application of each individual layer, which height profile is compared to a stored height profile having been established after the application of the preceding layer. By location-dependent subtractions of the height profiles, one obtains the location-dependent thickness information of the newly provided layer. When, after the application of each layer, the created thickness profile is summed up to a total thickness profile, then, after the end of the production, the total thickness profile of the produced object is obtained, such that, by combining the last-measured surface profile with the total thickness profile, conclusions to the shape of the carrier body may be drawn in order to thereby determine, for example, an undesired deformation thereof. Thus, the final form of the interior wall of the finished object results from determination of the height information after application of the last layer and consideration of the local sum of the provided material thicknesses. The inventive method is applicable even when the wound, or applied in layers, material is compressible, wherein then, however, a possibly created compression in the direction of the normal of the surface, thus, the direction which, location-dependent, always stands perpendicularly on the surface, must be known from corresponding tests.
In a further preferred embodiment example of the present invention, the production of automobile tires is monitored and controlled according to the invention. Thereby, in particular the application of rubber layers on a tire body is monitored. The rubber layers are provided on the basic body in several layers by winding a rubber material onto a cylindrical basic body, wherein according to the invention after each layer a height profile of the provided layer is established. Thereby, in particular air inclusions can be substantiated in a safe manner, which will be hardly detectable after finishing the entire tire, as the air, for example, may be compressed, such that no local increase of the height profile can be proven on the surface of the finished tire. Nevertheless, in the interior of the tire the connection between two successive layers is affected by the entrapped air volume, wherein it has to be taken into account that high temperatures may occur in the operation of a tire, such that the entrapped air thermally expands and thereby possibly deteriorates the mechanical connection between the two rubber layers concerned and, in an extreme case, even separates the two layers over the entire width of the tire from each other. According to the invention, now such air inclusion may be recognized safely in that the force effecting on an entrapped air bubble by merely one other rubber layer is small, such that the entrapped air bubble merely is slightly compressed and can easily be verified as a local increase within a height profile of the tire surface.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following, preferred embodiment examples of the present invention are illustrated in detail, with reference to the accompanying drawings. Thereby,
FIG. 1 shows a method for monitoring the manufacture.
FIG. 2 monitoring a preformed part consisting of wound layer material.
FIG. 3 system for monitoring and controlling a manufacturing process.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a flow chart, by means of which the inventive method for monitoring the manufacture of an object consisting of multiple material layers is explained in the following.
Thereby, first of all in a first manufacturing step 2 a material layer of the object to be manufactured is applied.
After applying the material layer, in a provision step 4 , a height profile of the surface of the object is provided, which is processed further in the subsequent step.
In the comparison step 6 , the provided height profile is compared to a reference information, wherein the reference information preferably is a desired height profile. If in comparison step 6 a comparison result is obtained which indicates that the material layer has been applied faultlessly, a release signal 8 is given which then prompts a new application of a further layer.
If comparison step 6 delivers a result indicating a faulty application of the material layer, an error signal 10 is given, which prompts the taking of error measures 12 .
As is evident from FIG. 1 , thus, during production the production can be terminated at any time as soon as an error signal 10 is given, which may lead to considerable cost savings when processing cost-intensive materials, as the material portion can be saved from the occurrence of the error signal 10 up to finishing the final product. Thus, when processing carbon fiber composites in layers, according to the invention considerable cost savings can be performed.
By means of FIG. 2 , in the following a preferred embodiment example of the present invention is to be illustrated, wherein the construction of a preformed part from a layer material is described, which material is provided in a long length on a roll and wherein the layer material during production is wound around a carrier body.
FIG. 2 shows a carrier body 20 , a layer material 22 , a sensor 24 , and a control 26 .
Via a first data connection 28 , control 26 is connected to the sensor 24 , and via a second data connection 30 to the carrier body 20 .
Thereby, the carrier body 20 , on the one hand, may become a part of the final product or may be removed at the end of the production process, wherein none of the two possibilities is preferred for the inventive method, as the method permits both possibilities.
At the beginning of the production, the layer material 22 is fixedly connected to the carrier body 20 at a receiving point 32 . In the following, it is considered that the product to be produced is rotated with the carrier body 20 during winding, and that the layer material 22 is provided from a constant direction tangentially on the carrier body 20 . In the top view onto the cylindrical carrier body 20 and the belt-shaped carrier material 22 , shown in FIG. 2 , thus the carrier body 20 during production is rotated with an angular velocity 34 (ω), such that the carrier material 22 , at the contact point 36 , is rolled tangentially onto the carrier body 20 . Thereby, an angle 38 (φ) between a reference plane 40 and the receiving point 32 is a measure for how many layers of the carrier material 22 already have been wound onto the carrier body 20 . Namely, when successively summing up the angle 38 starting from the beginning of the winding process, then per application of an entire layer of the layer material 22 an increase of the angle 38 of 2π is obtained.
Thereby, the sensor 24 determines during the rotation, dependent from the angle 38 , the distance 42 ( d ) between the sensor 24 and the wound carrier material 22 along a measuring line 44 .
Thereby, the sensor 24 determines a one-dimensional height profile of the surface of the wound carrier material 22 along the measuring line 44 , in dependency from angle 38 . The one-dimensional height profile is transferred via the data connection 28 to the control 26 , wherein at the same time the information to which angle 38 the transferred height profile belongs, also is transferred via the data connection 30 to the control 26 . By combining a plurality of one-dimensional height profiles with the angles 38 associated therewith, the control 26 calculates a two-dimensional height profile describing the surface of a completely wound layer of the layer material 22 , such that after finishing each individual layer, the complete 3D information of the surface of the object to be produced is available.
After respectively a complete winding of the layer material 22 around the carrier body 20 , the control 26 compares the determined 3D height profile to a desired height profile in order to evaluate whether a fault, as, for example, the entrapment of an air bubble, has occurred during the winding of the last layer. In this case, an error measure is taken, which may consist in, for example, the control 26 terminating the winding of the layer material 22 around the carrier body 20 , in order to sort out unfinished objects as rejects.
In the embodiment example of FIG. 3 , a system 50 for controlling and monitoring the manufacture of objects consisting of multiple material layers is represented. Thereby, the system comprises a control part 52 and a monitoring part 54 .
In a first procedure step, in an application step 56 the application of a material layer onto the body to be produced is controlled. Thereupon, in measuring step 58 the height profile of the applied layer is determined.
By means of a data connection 60 , the height profile is made available to the monitoring part 54 of the system 50 , which, in comparison step 62 , compares the height profile to a desired height profile.
When in comparison step 62 , a result is obtained which indicates a faultless application of the material layer during application step 56 , then a release information is transferred via a data interface 64 to the control part 52 of the system 50 , such that this can perform another application step. In this case, thus, a production cycle circle 66 closes, which comprises the entire application of a material layer and the inventive examination of the application of the material layer.
When comparison 62 delivers a result indicating a faulty application of the material layers in application step 56 , then an error signal is transferred to the control part 52 via a data interface 68 , such that this control part can control an error measure 70 , which, for example, comprises the removal of the object to be created from the production plant.
In the inventive embodiment example described in reference to FIG. 1 , after each application of a material layer a height profile is established, whereby according to the invention, it may be equally advantageous to determine a height profile only after applying a plurality of material layers for saving in this manner processing time of the testing procedure.
Although in the described forms of embodiment, a comparison of the measured height profile to a desired height profile is performed, according to the invention also a dynamically tracked, predicted desired height information can be used, which is based on the height profiles recorded up to then. So, it would be possible, for example, when determining a dropping below a desired material thickness, to calculate a material thickness profile of the next layer to be provided from the intended desired thickness of the object and the last-recorded height profile, in order to choose from a plurality of available material layers the one, whose application onto the object guarantees achieving the desired value, as the chosen material layer has a thickness profile suited to this aim.
According to the invention, the production of an object manufactured from multiple layers may be monitored also in this respect that the layer thicknesses of the successive layers are as homogenous as possible, thus, equally distributed. This is advantageous in particular when, for example, the strength of a finished object can not be derived merely from the thickness of the applied material, but when it must also be taken into account that individual functional material layers are arranged within the object as uniformly as possible. This is difficult to evaluate by means of a method examining a finished object only after finishing in a non-destructive manner.
In the described embodiment examples, a created height profile primarily is used for comparing it to a desired height profile in order to monitor the faultless progress of a production. Moreover, each height profile can be stored after comparing, such that, after finishing the production, a complete reconstructed three-dimensional image of the created object is available, for instance, for utilizing it further within the scope of electronic data processing. This is in particular highly advantageous when a complex-designed object must be created from possibly multiple different material layers, as by means of the inventive method each individual layer is measured after its application, such that a three-dimensional image of the inner construction of the finished object with a high local resolution can be created.
For the working of the embodiment example according to the invention, shown in FIG. 2 , in the beginning of the winding the layer material is provided on the carrier body along a predetermined line. During the rotation of the carrier body, the layer material passes a measuring line, at which the height information of the carrier body including the applied material is detected. To this aim, first it is presupposed that the carrier body itself consists of a material without gaps, a drum without gaps, respectively, such that before the application of the first material layer the location-dependent height information of the carrier body can be taken into account for determining the contact area.
Alternatively, the carrier body may also show gaps, which means, it may show recesses in its surface, whereby then first the height information after applying the first layer of the layer material must be measured in order to calculate the local position of the basic area (of the carrier body) by taking into account the local thickness of the layer material, said thickness being presumed as known or being measured beforehand. According to the invention, the method thus may also be applied for monitoring the production on a carrier body with surface interruptions, wherein then during the winding of the objects the height information is continuously detected along a reference line, which reference line is allocated to the rotational position of the carrier body. Thereby, just as with a carrier body with continuous surface, it is possible to permanently monitor whether the local material thickness, which is depending on the rotational position, corresponds to the desired values.
In the embodiment example of the present invention described in FIG. 2 , a one-dimensional measuring procedure is used as a measuring procedure for determining the height information, as provided, for example, by the light-section procedure. In the light-section procedure, a light line is projected onto the test body, which line is recorded with a matrix camera at a known angle to the projection direction. From the position of the light line in the camera image, after a calibration of the measuring system, the local height information along the light line can be inferred. However, the testing procedure presented here may be performed with all physical measuring procedures delivering a height information.
In particular, the inventive method is also independent from the manner in which the application of the layers is taking place and in which manner the height information after application of a layer is determined. What is important is in fact that the invention starts from determining a basic area corresponding to the interior wall of the created body, and the construction of the body is tracked by determining the height information after applying each individual layer. Therefore, also measuring procedures can be used which directly provide for a two-dimensional height profile, in which thus the height profile of a three-dimensional object does not have to be constructed first by means of an angle of rotation and a one-dimensional height profile, as this is the case in the embodiment example according to the invention in FIG. 2 .
Thus, also the strip-projection procedure comes into consideration as a method for determining a height profile, as well as other, non-optical methods, as, for example, a capacitive measuring procedure or also a tactile measuring procedure, in which the surface to be examined is mechanically read.
Although in the embodiment example of the present invention, which is described in FIG. 2 , the application of the layer material 22 onto the carrier body is monitored in respect to reaching a desired thickness, the control 26 also can be used to actively influence the intended desired thickness. When, for example, the layer material 22 is a rubber material, then a tension is exerted onto the supplied layer material 22 due to the drum (the carrier body 20 ) rotating at the angular velocity w. A tension of an elastic material, such as rubber, results in that the material stretches, which causes a thickness variation of the supplied layer material 22 . When now, for example, after applying a complete layer, the control 26 determines that the layer-dependent desired thickness of the materials is exceeded, then, for example, by varying the angular velocity 34 , thus, in the described case, by increasing it, the tension on the layer material 22 may be increased, by which the material is stretched more strongly and thus the next applied layer causes a smaller increase of the thickness.
A control, as described above, of an applied thickness of a layer material of a rubber compound is particularly advantageous in the production of tires, as herein, a precise observance of the total material thickness is important, whereby the above-described inventive method contributes to observing the material thickness in that a thickness alteration of the supplied layer material 22 can be compensated during production.
In the system for controlling and monitoring a production of an object composed of multiple layers, described in FIG. 3 , it is suggested that the method of controlling and the method of monitoring are performed such that the components participating in the methods are situated in spatial proximity to each other. However, it is perfectly possible to spatially separate the control part 52 and the monitoring part 54 of the system 50 , as shown in FIG. 3 , from each other, wherein the data connections 60 , 64 and 68 , which connect the control part 52 and the monitoring part 54 , may be based on cordless or on wire-bound technologies. In particular, also a connection via a computer network, as, for example, the internet, is possible, which is advantageous in case that the reference information in the form of a database is not available at the location of production, such that, for example, the method for controlling the production is performed at the production location, whereas the method for monitoring the production is performed at another location, as, for example, at a data processing center.
Depending on the circumstances, the inventive method for monitoring can be implemented in hardware or in software. The implementation can be performed on a digital storage medium, in particular a diskette or CD with electronically readable control signals, which can cooperate with a programmable computer system such that the inventive method for monitoring is performed. In general, the invention thus also consists of a computer program product with a program code stored on a machine-readable carrier for performing the inventive method, when the computer program product is running on a computer. In other words, the invention thus can be realized as a computer program with a program code for performing the method, when the computer program is running on a computer. | The manufacture of an object consisting of multiple material layers successively built up one upon the other can be monitored in an advantageous manner in that after the application of a material layer, a height profile of a circumference of the object is established, such that after the application of each material layer, a comparison with a reference information can be used for evaluating whether the preceding production step delivered a result which enables to draw the conclusion of a faultless application of the material layer. | 8 |
This is a continuation of application Ser. No. 07/577,102, filed Sep. 4, 1990, which is abandoned.
BACKGROUND OF THE INVENTION
1. Industrial Field of the Invention
The present invention relates to a method for pulling a silicon single crystal according to the Czochralski process, and more particularly to a method for achieving a uniform axial and radial oxygen concentration of a silicon single crystal.
2. Statement of the Related Art
When a silicon single crystal is prepared according to the Czochralski process, polycrystalline silicon as a material contained in a quartz crucible is heated to melt and form a silicon melt, into which a seed crystal is immersed, whereby the seed crystal is drawn slowly to grow a single crystal silicon rod. The surface of the quartz crucible in contact with the silicon melt (approximately 1,450° C.) is dissolved and evaporated in part as silicon monoxide from the surface of the melt. The balance of the dissolved surface is incorporated into the growing silicon single crystal. In general, the oxygen concentration distribution of the silicon single crystal pulled according to the Czochralski process is not uniform in the bulk, that is, axially higher at the portion solidified initially and lower at the portion solidified later. For example, the oxygen concentration of the portion solidified initially is 3×10 18 atoms/cc of oxygen, while that of the tail end portion of the pulled single crystal rod is exceedingly reduced to 6×10 17 atoms/cc. Radially, on the other hand, the concentration is higher at the center and lower at the periphery. The ratio of variation in oxygen concentration from center to periphery amounts to 15%.
Oxygen dissolved in silicon single crystal forms microdefects when subjected to heat treatment. The presence of dissolved oxygen in the active layer region of the surface of the semiconductor crystal substrate causes the maknig of nuclei which originate stacking faults during thermal oxidation of the surface, and which have an unfavorable influence on fundamental characteristics of semiconductor devices. In recent years, however, such microdefects are forced to be generated in the bulk of a semiconductor substrate so that the microdefects can be positively used only as a gettering center of impurities. In addition, to positively use of the microdefects, a technology has been developed whereby the active layer region is made defect-free with the help of gettering effect of the microdefects in the bulk. Therefore, oxygen of solid solution is indispensable now. Such a treatment is called an intrinsic gettering process which is an inevitable technology for semiconductor integrated circuits.
In this sense, it is required that the concentration of oxygen dissolved in pulled silicon single crystal is as uniform as possible both axially and radially. As such technologies for controlling oxygen concentration distribution in a silicon single-crystal rod there are the following:
(1) A method wherein the rotation of a quartz crucible is brought to a complete stop periodically to make use of fluid friction in the vicinity of the solid-liquid interface (Japanese Patent Examined Publication No. 53-29677).
(2) A method wherein an oxygen concentration profile in a silicon single-crystal rod is measured to control the rotation rate of the crucible so that the rotation will be varied in a reverse relationship with the measured profile (Japanes.e Patent Examined Publication No. 60-6911).
(3) A method wherein a silicon single-crystal rod and a quartz crucible rotate in a reverse direction with each other. The silicon single-crystal rod rotates faster than the crucible. The rotation rate of the quartz crucible increases with the length of the silicon rod increasing in growth (Japanese Patent Laid-Open Publication No. 57-135796). None of them are satisfactory.
According to the method (1), it is necessary that the quartz crucible should be completely suspended momentarily. The large volume of the melt contained in the crucible in accordance with the recent trend where the diameters of the quartz crucibles are large makes it hard physically to stop the crucible abruptly because of the mass of the melt and the mechanical structure of a driving means. A momentary complete suspension of the crucible, if possible, would produce a thermal instability of the melt within the quartz crucible. As a result, an unfavorable solidification of the melt in part at the bottom of the crucible would follow. Further, such a mere momentary complete stop of the crucible would not improve an axial oxygen concentration profile.
According to the method (2), when the oxygen concentration is reducing along the length of the silicon rod, the rotation rate of the crucible is caused to increase. This method is not practical, since a complicated procedure will follow in determining a suitable rate of rotation of the quartz crucible. Furthermore, this method would not improve the radial oxygen concentration profile.
The method (3) resembles the method (2). If attention is paid only to the rotation of the quartz crucible, this method is equivalent to a case where the oxygen concentration profile in a silicon single crystal reduces lengthwise uniformly. According to this method, the rotation of the crystal is selected to be in a reverse direction relative to the rotation of the quartz crucible, and further, programmed to be progressively faster. This method, however, does not necessarily improve the radial oxygen concentration distribution.
SUMMARY OF THE INVENTION
In the light of the drawbacks of conventional technologies as stated above, the present invention provides a process for facilitating to control the variance in the axial and radial oxygen concentration profile of a silicon single-crystal rod drawn from a quartz crucible according to the Czochralski process not more than 10%, preferably 5% or less.
In order to realize the above process according to the present invention, in pulling a silicon single crystal from a silicon melt within a quartz crucible according to the Czochralski process, while the quartz crucible is maintained at a reference rate of rotation more than zero, exclusive of zero, the reference rates of rotation of the crucible is controlled in accordance with a predetermined program for the duration of the entire pulling process. Further, an increase or reduction in the rotation rate in a pulse-like pattern superimposed to the reference rotation of the crucible (i.e., change in the amplitude as shown in FIG. 15) and an increase or reduction in the cycle of the pulse-like pattern (i.e., change in the frequency as shown in FIG. 18) are controlled according to a predetermined program.
Therefore, it is possible to shape the above stated program into a cyclic pattern wherein the crucible rotation rate increases or decreases with passage of time (FIG. 15). The retention time during which a certain reference rate of rotation is held and the retention time during which a positive or negative additional rate of rotation superimposed ahead of or following the reference rate can be increased or reduced respectively in the course of the pulling of a silicon single crystal (FIG. 22).
The reference rate of the crucible rotation can be arbitrarily set between 0.1 to 50 rpm. In case the reference rate of rotation is 0.1 rpm or less, the temperature of the melt in the quartz crucible would turn uneven. In some cases, part of the silicon melt often solidifies at the bottom of the crucible, thereby making it difficult to pull the crystal. On the other hand, in case the reference rate of rotation is 50 rpm and over, the melt itself would vibrate and undulate by mechanical causes, whereby making it also difficult to draw the crystal.
As an embodiment according to the present invention, the reference rate of rotation stated above is set, for instance, at 8 or 10 rpm. The rate of rotation is increased or decreased at a predetermined cycle in a pulse-like pattern. In general, the superimposed change in the rate ranges from 0.1 to 50 rpm. Owing to a structure of the rotating mechanism and a possible eccentricity of the quartz crucible of the pulling device it is preferable that the upper limit of the total actual rate of rotation (reference rate of rotation +maximal superimposed rate) should be set at 50 rpm. In case a reference rate of rotation is 8 rpm, the upper limit of the superimposed change is in the vicinity of 42 rpm. Under this condition, as in the case wherein the rotation rate is held at a reference rate, that is, constant, the oxygen concentration is higher at the initially solidified portion of the pulled single crystal, and lower as the solidification closes to the tail portion. But the oxygen concentration is in general at a higher level and radially more uniform than held at the constant rate of 8 rpm and an increase of the value of the superimposed change of rate in accordance with an increase of the growth length of the pulled single crystal will result in dramatically uniform distribution of oxygen concentration in the axial and radial direction.
In case the quartz crucible is subjected to change in the rotation rate in a pulse-like pattern, prolongation of the retention time of increased rotation rate and/or the retention time of reference rotation rate causes the axial oxygen concentration of a pulled silicon single crystal to be generally increased compared with that at the reference rate. The retention time of increased rotation rates can be suitably selected between 1 and 600 sec. The effect of an increase in oxygen concentration cannot be seen below or above the above range. The range of the retention time should preferably be 10 to 180 sec, within which the above effect can be better expected. Too short retention time of increased rotation rate causes a failure in follow-up of the movement of the silicon melt with the movement of the quartz crucible. Too long retention time does not allow the uniformity in the radial oxygen concentration. The ratio of the retention time of reference rotation rate to the retention time of increased rotation rate can be suitably selected between 1:99 and 99:1. The range of the ratio should preferably be 2:8 to 8:2, within which the effect of an increase in oxygen concentration can be obtained. It is to be noted that the retention time and the rotation rate can be increased at the same time according to the length of the pulled silicon single crystal.
The process according to the present invention determines the rotation rate of the quartz crucible to be increase or decreased in a pulse-like pattern based on the axial oxygen concentration profile of a silicon single crystal rod with the constant reference rotation rate of a quartz crucible. Variety of pulse-like patterns including the rotation rate and the retention times allows a desired axial oxygen concentration profile to be obtained and the operation of the process is quite easy. Further, the application of the present invention will allow the variance in the radial oxygen concentration profile to be controlled less than 10%, and it is possible to make the variance even less than 5%.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graph showing in part how the quartz crucible used in Embodiment 1 rotates.
FIG. 2 is a graph showing the axial oxygen concentration of the silicon single crystals obtained according to Embodiments 1 and 2 and Comparison Example 1.
FIG. 3 is a graph showing in part how the quartz crucible used in Embodiment 2 rotates.
FIG. 4 is a graph showing how the quartz crucible used in Comparison Example 1 rotates.
FIG. 5 is a graph showing the axial oxygen concentration of the silicon single crystals obtained according to Embodiments 1, 3 and 4 and Comparison Example 1.
FIG. 6 is a graph showing in part how the quartz crucible used in Embodiment 3 rotates.
FIG. 7 is a graph showing in part how the quartz crucible used in Embodiment 4 rotates.
FIG. 8 is a graph showing in part how the quartz crucible used in Embodiment 5 rotates.
FIG. 9 is a graph showing the axial oxygen concentration of the silicon single crystals obtained according to Embodiments 5 through 7 and Comparison Example 1.
FIG. 10 is a graph showing in part how the quartz crucible used in Embodiment 6 rotates.
FIG. 11 is a graph showing in part how the quartz crucible used in Embodiment 7 rotates.
FIG. 12 is a graph showing in part how the quartz crucible used in Embodiment 8 rotates.
FIG. 13 is a graph showing the axial oxygen concentration of the silicon single crystals obtained according to Embodiments 5, 8 and 9 and Comparison Example 1.
FIG. 14 is a graph showing in part how the quartz crucible used in Embodiment 9 rotates.
FIG. 15 is a graph showing in part how the quartz crucible used in Embodiment 10 rotates.
FIG. 16 is a graph showing the axial oxygen concentration of the silicon single crystals obtained according to Embodiment 10 and Comparison Example 1.
FIG. 17 is a graph showing how the cycle of change in rotation rate of the quartz crucible used in Embodiment 11 is altered.
FIG. 18 is a graph showing schematically how the quartz crucible used in Embodiment 11 rotates.
FIG. 19 is a graph showing the axial oxygen concentration of the silicon single crystals obtained according to Embodiment 11 and Comparison Example 1.
FIG. 20 is a graph showing how the cycle of change in rotation rate of the quartz crucible used in Embodiment 11 is altered.
FIG. 21 is a graph showing how the rotation rate of the quartz crucible used in Embodiment 12 is changed.
FIG. 22 is a graph showing schematically how the quartz crucible used in Embodiment 12 rotates.
FIG. 23 is a graph showing the axial oxygen concentration of the silicon single crystals obtained according to Embodiment 12 and Comparison Example 1.
FIG. 24 is a graph showing the radial oxygen concentration of the silicon single crystal obtained according to Embodiment 13.
FIG. 25 is a graph showing the radial oxygen concentration of the silicon single crystal obtained according to Comparison Example 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be described further more particularly by enumerating the preferred embodiments. It is needless to say that the present invention is not restricted only to the preferred embodiments.
EMBODIMENT 1
Case wherein both the range (2.0 rpm) and the cycle (60 sec; the period of time of reference rotation/the period of time of accelerated rotation=1/1) of change in the rotation rate are constant
A silicon single crystal 150 mm in diameter and about 40 cm in length was pulled from a quartz crucible 440 mm in internal diameter containing 30 kg of molten silicon under the conditions written below. The reference rate of rotation of the quartz crucible was 8.0 rpm as shown in FIG. 1, the range of change in the rotation rate was maintained at 2.0 rpm (i.e., the accelerated rate of rotation was 10.0 rpm.), and the cycle of change in the rate was maintained at 60 sec (the period of time of reference rotation/the period of time of accelerated rotation =1/1). The crystal rotation rate was 20 rpm in the reverse direction relative to the quartz crucible rotation.
The measurements of the axial oxygen concentration of the silicon single crystal thus obtained are shown in FIGS. 2 and 5. These figures indicate that the axial oxygen concentration of the silicon single crystal obtained by this embodiment was improved compared with that of a silicon single crystal (Comparison Example 1 to be described later) obtained by a conventional method. The measurement of the axial oxygen concentration of the silicon single crystal was conducted as follows: With the shoulder portion of the silicon single crystal as a starting point, the crystal thus obtained was cut into wafers each 2.0 mm thick at intervals of 5 cm. Then a wet etching was performed on both surfaces of the wafers, whereby the oxygen concentrations of the center portions thereof were measured by Fourier transform infrared absorption spectrophotometer.
EMBODIMENT 2
Case wherein both the range (4.0 rpm) and the cycle (60 sec; the period of time of reference rotation/the period of time of accelerated rotation=1/1) of change in the rotation rate are constant
As shown in FIG. 3, a silicon single crystal was obtained in the same method as Embodiment 1, except for the range of change in the rotation rate set at 4.0 rpm (i.e., the accelerated rotation rate is 12.0 rpm.) The oxygen concentration of the silicon single crystal was measured in the same process as Embodiment 1, the result of which is shown in FIG. 2. This figure confirms that the oxygen concentration of the silicon single crystal obtained by this embodiment was furthermore improved compared with Comparison Example 1 (to be described later) and Embodiment 1.
COMPARISON EXAMPLE 1
Case where no change in the rotation rate is made (conventional methods)
A silicon single crystal 150 mm in diameter and 40 cm in length was pulled from a quartz crucible 440 mm in internal diameter containing 30 kg of molten silicon. As shown in FIG. 4, the reference rate of rotation of the quartz crucible was 8.0 rpm with the range of change in the rotation rate being null, i.e., no change in the rate.
The measurement of the oxygen concentration of the silicon single crystal thus obtained was conducted in the same process as in Embodiment 1, the result of which is shown in FIGS. 2, 5, 9, 13, 16, 19 and 23 for comparison.
EMBODIMENT 3
Case wherein both the range (2.0 rpm) and the cycle (30 sec; the period of time of reference rotation/the period of time of accelerated rotation=1/1) of change in the rotation rate are constant
As shown in FIG. 6, a silicon single crystal was obtained in the same method as Embodiment 1 except for the cycle of change in the rotation rate being set at 30 sec. The measurement of oxygen concentration of the silicon single crystal was conducted in the same process as Embodiment 1, the result of which is shown in FIG. 5. This figure confirms the oxygen concentration of the silicon single crystal obtained according to the present embodiment was lower than that of Embodiment 1, but higher than that of Comparison Example 1.
EMBODIMENT 4
Case wherein the range (2.0 rpm) and the cycle (120 sec; the period of time of reference rotation/the period of time of accelerated rotation=1/1) of chanqe in the rotation rate are constant
As shown in FIG. 7, a silicon single crystal was obtained in the same method as Embodiment 1 except for the cycle of change in the rotation rate being set at 120 sec. The measurement of oxygen concentration of the silicon single crystal thus obtained was conducted in the same process as Embodiment 1, the result of which is shown in FIG. 5. This figure confirms that the axial oxygen concentration profile of the silicon single crystal obtained according to the present embodiment was higher in value and improved in uniformity compared with that of Embodiments 1 and 3.
EMBODIMENT 5
Case wherein both the range (4.0 rpm) and the cycle (120 sec; the period of time of reference rotation/the period of time of accelerated rotation=1/1) of change in the rotation rate are constant
As shown in FIG. 8, a silicon single crystal was obtained in the same method as Embodiment 1 except for the range of change in the rotation rate being set at 4.0 rpm (i. e., the accelerated rate of rotation is 12.0 rpm.) and the cycle of change in the rotation rate being set at 120 sec. The measurement of oxygen concentration of the silicon single crystal thus obtained was conducted in the same process as Embodiment 1, the result of which is shown in FIG. 9. This figure confirms that the axial oxygen concentration profile of the silicon single crystal obtained according to the present embodiment was remarkably increased in value and improved in uniformity compared with that of Comparison Example 1.
EMBODIMENT 6
Case wherein both the range (4.0 rpm) and the cycle (120 sec; the period of time of reference rotation/the period of time of accelerated rotation=7/1) of change in the rotation rate are constant
As shown in FIG. 10, a silicon single crystal was obtained in the same method as Embodiment 5 except for the period of time of reference rotation/the period of time of accelerated rotation=7/1. The measurement of oxygen concentration of the silicon single crystal thus obtained was conducted in the same process as Embodiment 1, the result of which is shown in FIG. 9. This figure confirms that the axial oxygen concentration profile of the silicon single crystal obtained according to the present embodiment was improved in uniformity compared with Comparison Example 1.
EMBODIMENT 7
Case wherein both the range (4.0 rpm) and the cycle (120 sec; the period of time of reference rotation/the period of time of accelerated rotation=3/1) of change in the rotation rate are constant
As shown in FIG. 11, a silicon single crystal was obtained in the same method as Embodiment 5 except for the period of time of reference rotation/the period of time of accelerated rotation=3/1. The measurement of oxygen concentration of the silicon single crystal thus obtained was conducted in the same process as Embodiment 1, the result of which is shown in FIG. 9. This figure confirms that the oxygen concentration of the silicon single crystal obtained according to the present embodiment was lower than that of Embodiment 5, but the profile in the axial direction was improved in uniformity compared with that of Embodiment 6.
EMBODIMENT 8
Case wherein both the range (4.0 rpm) and the cycle (120 sec; the period of time of reference rotation/the period of time of accelerated rotation=1/1) of change in the rotation rate are constant with reference rotation rate (10.0 rpm) increased
As shown in FIG. 12, a silicon single crystal was obtained in the same method as Embodiment 5 except for the reference rotation rate set at 10.0 rpm. The measurement of oxygen concentration of the silicon single crystal thus obtained was conducted in the same process as Embodiment 1, the result of which is shown in FIG. 13. This figure confirms that the axial oxygen concentration profile of the silicon single crystal obtained according to the present embodiment was improved in uniformity compared with that of Embodiment 5.
EMBODIMENT 9
Case wherein both the range (4.0 rpm) and the cycle (120 sec; the period of time of reference rotation/the period of time of accelerated rotation=1/1) of change in the rotation rate are constant with reference rotation rate (12.0 rpm) increased
As shown in FIG. 14, a silicon single crystal was obtained in the same method as Embodiment 5 except for the reference rotation rate set at 12.0 rpm. The measurement of oxygen concentration of the silicon single crystal thus obtained was conducted in the same process as Embodiment 1, the result of which is shown in FIG. 13. This figure confirms that the axial oxygen concentration profile of the silicon single crystal obtained according to the present embodiment was furthermore improved in uniformity compared with that of Embodiment 8.
EMBODIMENT 10
Case wherein the cycle (60 sec; the period of time of reference rotation/the period of time of accelerated rotation =1/1) of change in the rotation rate is constant with the range of change in the rotation rate varied
As shown FIG. 15, a silicon single crystal was obtained in the same method as Embodiment 1 except that the range of change in the rotation rate of the quartz crucible was maintained at 2.0 rpm for the length of the silicon single crystal in the pulling process being 0 to 20 cm, gradually increased from 2.0 to 4.0 rpm for the length of the silicon single crystal being 20 cm to 40 cm, and maintained at 4.0 rpm for the length of the silicon single crystal being 40 cm and over. The measurement of oxygen concentration of the silicon single crystal thus obtained was conducted in the same process as Embodiment 1, the result of which is shown in FIG. 16. This figure makes it clear that the axial oxygen concentration of the silicon single crystal obtained according to the present embodiment was far improved in its uniformity compared with that of Comparison Example 1, and that such a phenomenon that the longer the pulled length of the silicon single crystal was, the lower the oxygen concentration thereof became, as seen in Comparison Example 1 and Embodiments 1 through 9 was eliminated, that is, the axial oxygen concentration of the silicon single crystal was uniform.
EMBODIMENT 11
Case wherein the range (2.0 rpm) and the period of time of reference rotation/the period of time of accelerated rotation=1/1 is constant with only the cycle of change in the rotation rate varied
As shown in FIG. 17, a silicon single crystal was obtained in the same method as Embodiment 1 except that the cycle of change in the rotation rate of the quartz crucible was maintained at 60 sec for the length of the silicon single crystal in the pulling process being 0 to 20 cm, gradually lengthened from 60 to 120 sec for the length of the silicon single crystal being 20 to 35 cm, and maintained at 120 sec for the length of the silicon single crystal being 35 cm and over. It is to be noted that FIG. 18 typically shows how the cycle of change in the rotation rate of the quartz crucible is varied. The measurement of oxygen concentration of the silicon single crystal thus obtained was conducted in the same process as Embodiment 1, the result of which is shown in FIG. 19. This figure makes it clear that the oxygen concentration of the silicon single crystal obtained according to the present embodiment was far improved in profile uniformity compared with that of Comparison Example 1, and that such a phenomenon that the longer the pulled length of the silicon single crystal was, the lower the oxygen concentration thereof became, as seen in Comparison Example 1 and Embodiments 1 through 9 was eliminated, that is, the axial oxygen concentration of the silicon single crystal was uniform.
EMBODIMENT 12
Case wherein the period of time of reference rotation/the period of time of accelerated rotation=1/1 is constant with both the range and the cycle of change in the rotation rate altered
A silicon single crystal was obtained in the same method as Embodiment 1 except that as shown in FIG. 20, the cycle of change in the rotation rate of the quartz crucible was maintained at 60 sec for the length of the silicon single crystal in the pulling process being 0 to 20 cm, gradually lengthened from 60 to 80 sec for the length of the silicon single crystal being 20 to 40 cm, and maintained at 80 sec for the length of the silicon single crystal being 40 cm and over, and except that, as shown in FIG. 21, the range of change in the rotation rate of the quartz crucible was maintained at 2.0 rpm for the length of the silicon single crystal in the pulling process being 0 to 20 cm, gradually lengthened from 2.0 rpm to 3.0 rpm for the length of the silicon single crystal being 20 to 40 cm and maintained at 3.0 rpm for the length of the silicon crystal being 40 cm and over. FIG. 22 shows schematically how both the range and the cycle of change in the rotation rate of the quartz crucible are varied. The measurement of oxygen concentration of the silicon single crystal thus obtained was conducted in the same process as Embodiment 1, the result of which is shown in FIG. 23. This figure makes it clear that the oxygen concentration of the silicon single crystal obtained according to the present embodiment was far improved in profile uniformity compared with that of Comparison Example 1, and that such a phenomenon that the longer the pulled length of the silicon single crystal was, the lower the oxygen concentration thereof became, as seen in Comparison Example 1 and Embodiments 1 through 9 was eliminated, that is, the axial oxygen concentration of the silicon single crystal was uniform.
EMBODIMENT 13
Case wherein both the range (6.0 rpm) and the cvcle (60 sec; the period of time of reference rotation/the period of time of accelerated rotation=1/1) of chanqe in the rota
tion rate are constant
A silicon single crystal 150 mm in diameter and about 80 cm in length was pulled from a quartz crucible 440 mm in internal diameter containing 60 kg of molten silicon under the conditions written below. The reference rate of rotation of the quartz crucible was 8.0 rpm, the range of change in the rotation rate was maintained at 6.0 rpm (i.e., the accelerated rate of rotation was 14.0 rpm.), and the cycle of change in the rate was also maintained at 60 sec (the period of time of reference rotation/the period of time of accelerated rotation=1/1). The crystal rotation rate was 20 rpm in the reverse direction relative to the quartz crucible rotation.
The measurements of the radial oxygen concentration distribution of a wafer cut out at the position 65 cm away from the shoulder portion of the silicon single crystal thus obtained are shown in FIG. 24. This figure indicates that the radial oxygen concentration distribution of the silicon single crystal obtained according to the present embodiment was far more uniform than that of the silicon single crystal obtained according to the conventional process (Comparison Example 2 to be described later). It is to be noted that the measurement of the radial oxygen concentration of the silicon single crystal was conducted as follows: A position 5 mm away from the periphery of the wafer cut out from the silicon single crystal was set as a starting point, therefrom the oxygen concentration was measured at positions located at an interval of 5 mm towards the center of the wafer by way of Fourier transform infrared absorption spectrophotometer, as in Embodiment 1.
COMPARISON EXAMPLE 2
Case wherein no change in the rotation rate is made (a conventional method)
A silicon single crystal 150 mm in diameter and about 80 cm in length was pulled from a quartz crucible 440 mm in internal diameter containing 60 kg of molten silicon under the conditions written below. The reference rotation rate of the quartz crucible was maintained at 15.0 rpm. No change in the rotation rate was made. The crystal rotation rate was 20 rpm in the reverse direction relative to the quartz crucible rotation.
The measurements of the radial oxygen concentration distribution of a wafer cut out at the position 65 cm away from the shoulder portion of the silicon single crystal in the same method as Embodiment 13 is shown in FIG. 25. This figure indicates that the central oxygen concentration distribution of the wafer was uniform but abruptly lowered in the vicinity of the periphery. This means that the radial oxygen concentration distribution was extremely uneven. The differences between the maximum and the minimum values amounted to 25% of the minimum.
As stated above, the method for pulling silicon single crystal according to the present invention allows (a) to pull a silicon single crystal with a high oxygen concentration with ease, (b) to make even the radial and axial oxygen concentration and (c) to prepare industrially crystals provided with a desired axial oxygen concentration profile or crystals provided with a desired oxygen concentration level, because the process according to the present invention permits the pulse-pattern change in the crucible rotation rate to be superimposed to the reference rotation rate, thereby enabling to know in advance the effect of the change in the crucible rotation rate. This brings about a great industrial success. | This is a new method for pulling a silicon single crystal. When the silicon single crystal is pulled from a quartz crucible which is provided with a rotation rate more than zero, exclusive of zero rpm according to the Czochralski process, a reference rotation rate of the quartz crucible is controlled by a predetermined program. This method is characterized in that a pulse-like increase or decrease in a rotation rate is superimposed to the reference rotation rate and differences in and cycles of the rotation rate are set by the predetermined program. | 2 |
BACKGROUND
1. Technical Field
The disclosure generally relates to repair of metal components.
2. Description of the Related Art
The manufacture, service and/or repair of metal components, such as gas turbine engines, oftentimes require localized heating of specified areas of the components. This can be done, for example, to allow for stress relief, metal forming and/or brazing applications. Localized heating is preferred when processing the entire component in an isothermal heat treatment oven could adversely affect the metallographic properties of the materials of the component, or for larger parts that might warp or otherwise deform during heat treatment.
In this regard, prior art localized heating methods include resistance and induction heating. Induction heating methods tend to be costly, afford little process control, and require extensive experience of an operator in order to match induction coils to both the induction generator and the component/cross sectional area being heated. In contrast, resistance heating is somewhat limited in that the power supplies are current matched to specific heating element designs. The necessity in the prior art of matching the power supplies and the heating elements has typically resulted in rather generic heating assemblies in the form of blankets that typically are much larger than the areas that require heating.
SUMMARY
Systems and methods for providing localized heat treatment of metal components are provided. In this regard, a representative embodiment of such a method comprises: identifying a portion of a metal component to which localized heat treatment is to be performed; shielding an area in a vicinity of the portion of the metal component; and directing electromagnetic energy in the infrared (IR) spectrum toward the portion of the metal component such that the portion is heated to a desired temperature and such that the area in the vicinity of the portion that is subjected to shielding does not heat to the temperature desired for the heat treatment.
An embodiment of a system for providing localized heat treatment of metal components comprises: a non-oxidizing environment positioned about at least a portion of a component that is to be heat treated; a heating device having an infrared (IR) heating element operative to propagate electromagnetic energy in the IR spectrum responsive to an electrical input; and a shield positioned to obstruct a line-of-sight between the IR heating element and an area of the component located adjacent the portion that is to be heat treated.
Other systems, methods, features and/or advantages of this disclosure will be or may become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features and/or advantages be included within this description and be within the scope of the present disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
Many aspects of the disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. While several embodiments are described in connection with these drawings, there is no intent to limit the disclosure to the embodiments disclosed herein. On the contrary, the intent is to cover all alternatives, modifications and equivalents.
FIG. 1 is a schematic view of an embodiment of an infrared heating assembly.
FIG. 2 is a schematic diagram depicting an embodiment of a section of a gas turbine engine with heat shielding positioned adjacent a selected portion that is to be heat treated.
FIG. 3 is a schematic diagram depicting the section of gas turbine engine of FIG. 2 , with an embodiment of an infrared heating device positioned to locally heat the selected portion.
FIG. 4 is a schematic diagram the section of gas turbine engine of FIG. 2 , with an embodiment of an enclosure positioned about the selected portion that is being heat treated to provide a non-oxidizing environment.
DETAILED DESCRIPTION
As will be described in detail here with respect to several exemplary embodiments, systems and methods for providing localized heat treatment of metal components are provided. It should be noted that although representative implementations will be described herein with reference to heat treatment of gas turbine engine components, various other components could be heat treated using similar techniques.
In this regard, FIG. 1 depicts an exemplary embodiment of an infrared heating assembly 100 . As shown in FIG. 1 , assembly 100 generally includes a mounting arm 102 and a heating device 104 . The heating device incorporates a housing 106 that mounts an mounts an element 108 . Element 108 emits electromagnetic energy in the infrared (IR) spectrum responsive to electrical input provided by cable 110 . A mirror 112 , such as a parabolic mirror, is located within the housing to direct the IR energy outwardly from the housing. Selection of a suitable element is based, at least in part, on the range of temperatures desired for heat treating a component.
Mounting arm 102 enables the heating device 104 to be positioned so that the energy emitted by the element 108 can be directed toward an area of a component that is to be heat treated. In some embodiments, the mounting arm exhibits an articulated configuration to enable such positioning. Notably, the ability to manipulate positioning of the heating device via the mounting arm may make heat treatment of components possible without necessitating removal of such components from an assembly. By way of example, if the component that is to be heat treated is a portion of a turbine casing, the casing may not need to be removed from a nacelle to which the casing is mounted.
In the embodiment of FIG. 1 , optional input and output coolant lines 114 and 116 , respectively, provide a flow of liquid coolant to the heating device 104 . The flow of coolant prevents excess heat from damaging the heating device. Additionally or alternatively, various other types of cooling can be used, such as air cooling provided by fans.
The embodiment of FIG. 1 is designed to provide localized heating to a substantially contiguous area. However, various other embodiments can provide simultaneous localized heating of areas that are spaced from each other. Notably, in some embodiments, this can be accomplished by providing an array of elements in a single heating device and/or by using multiple heating devices during a heat treatment, for example.
As shown in FIG. 2 , a section of gas turbine engine casing 200 formed of Titanium is provided that includes a weld-repaired flange 202 . Localized heating of the flange is desired in order to relieve stresses in the material associated with the flange. In this regard, reference is made to FIG. 3 , which depicts an embodiment of an infrared heating assembly 300 that is positioned to perform such heat treating.
As shown in FIG. 3 , assembly 300 is positioned so that the heating device 302 directs IR energy toward the flange 202 . Note that the heating device is not attached to the casing, as would typically occur during a resistance or inductive heating process. This is because the IR energy is propagated through free space from the heating device toward the flange, thereby rendering physical attachment of the heating device and the casing unnecessary.
Also shown in FIG. 3 is a shield 304 that inhibits IR energy from excessively heating material that is not intended to be heat treated. In this embodiment, shield 304 is formed of a sheet of Titanium that incorporates a cut-out 306 .
The shield is positioned so that the cut-out is aligned with the flange, thereby enabling a line-of-sight to be established between the element of the heating device and the flange. As shown in the embodiment of FIG. 3 , positioning of the shield can be accomplished using metal foil 308 (e.g., Titanium foil) to attach the shield to the casing. In other applications, various clamps and/or other attachment techniques can be used. For instance, in some applications, a shield can be held in position by gravity and/or coordinating shapes of the shield and the component, thereby rendering the use of additional attachment components unnecessary.
In some embodiments, a metallic foil interface (not shown) can be used between the heating element and component that is to be heated in order to establish more uniform temperature gradients. Of particular interest is using Titanium foil with Titanium components. Such a technique may not only help with the temperature gradients, but also can be useful as a gettering device to absorb contaminates that may out-gas from the element and component during heat-up. In the embodiment of FIG. 3 , however, a metallic foil interface is not use. Instead, a purge gas line 310 is provided to vent unwanted gasses generated by the heat treatment.
A thermocouple 312 is attached to the casing in a vicinity of the heat treatment. The thermocouple enables monitoring of the casing temperature to ensure that the heat treatment is performed as desired.
As shown in FIG. 4 , at least the portion of the casing that is to be heat treated is located within a non-oxidizing environment. By way of example, such an environment can be formed by a heat resistant enclosure 402 that is flooded with an inert gas, such Argon. Argon may be deemed suitable in some applications because Argon is heavier than air. Thus, depending upon the configuration of the containment being used and the location of the component that is to be heat treated, a gas that is denser than air may be helpful. This is because the gas tends to sink to the bottom of the containment, thereby displacing oxygen from the lower portions of the containment that may surround the area that is to be heat treated.
In other embodiments, other gasses can be used, with the selection of such gasses being based, at least in part, on the materials being treated. For instance, for some materials, a gas such as Nitrogen could be used. In still other embodiments, the heat resistant enclosure could be a vacuum chamber designed to be evacuated of oxygen.
In the embodiment of FIG. 4 , enclosure 402 is formed in part by the casing that is to be heat treated and in part by a flexible material. In particular, the material is a transparent vinyl, e.g., polyvinyl chloride sheeting (such as manufactured by Polmershapes™), which facilitates visual monitoring of the heating process. The transparent vinyl is draped over an optional support frame 404 and tape 406 is used to form a seal between the flexible material and the casing.
Additionally or alternately, a cooling device (not shown) can be used to provide localized cooling, such as to areas adjacent to those areas that are to be heat-treated. In some embodiments, the cooling device can be a cooling fan and/or a closed-loop cooling system, such as one that uses a liquid (e.g. water), for providing cooling.
It should be emphasized that the above-described embodiments are merely possible examples of implementations set forth for a clear understanding of the principles of this disclosure. Many variations and modifications may be made to the above-described embodiments without departing substantially from the spirit and principles of the disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the accompanying claims. | Systems and methods for providing localized heat treatment of metal components are provided. In this regard, a representative method includes: identifying a portion of a metal component to which localized heat treatment is to be performed; shielding an area in a vicinity of the portion of the metal component; and directing electromagnetic energy in the infrared (IR) spectrum toward the portion of the metal component such that the portion is heated to a desired temperature and such that the area in the vicinity of the portion that is subjected to shielding does not heat to the temperature desired for the heat treatment. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to turbine engines, and more particularly to multidirectional turbine engines.
2. Description of the Prior Art
A gas turbine is an engine system comprising generally of a compressor, a combustion chamber, and a turbine. In a conventional gas turbine engine, the air compressor is mechanically coupled to the combustion chamber, which in turn is coupled to the turbine. A gas turbine engine of this kind operates by compressing air in the compressor to high pressure. The compressed air is communicated to the combustion chamber, where it is mixed with gas and ignited to undergo combustion. The resulting combustion produces a high pressure, high velocity gas mixture that is directed to the turbine, motivating the turbine to generate force. The gas mixture is expelled through a nozzle in the turbine, generating thrust by accelerating the hot exhaust gas mixture to atmospheric pressure. The thrust output energy can be used to power aircraft, trains, ships, and even tanks. The present invention is directed to a gas turbine engine for jets, but one of ordinary skill in the art would recognize its uses for other types of powered crafts.
In a jet engine, it is generally necessary to employ multiple turbines to generate greater thrust than can be achieved by one turbine alone. For engines that employ multiple turbines, the turbines are generally connected in series, with one turbine behind another. In this kind of gas turbine engine, the turbines are mounted on the same side of the compressor such that exhaust from the first turbine is transferred to the second turbine. The connection of turbines in series does not maximize the possible thrust output of the turbines.
For example, U.S. Pat. No. 6,968,698 to Walsh et al. teaches a gas turbine engine having three turbines arranged to flow in series. According to Walsh et al., the first turbine is arranged to drive a first compressor, the second turbine is arranged to drive a second compressor, and the third turbine is arranged to drive an output shaft. The turbines are arranged in series on the downstream side the combustor. Because the turbines are arranged in series, the thrust output is dissipated as the energy produced by the combustion travels from turbine to turbine, with only the third turbine arranged to drive the output shaft. In the gas turbine engine taught by Walsh et al., the combustion of high velocity, high pressure gas mixture from the combustion chamber cannot be simultaneously and equally directed to the three turbines to generate maximum thrust because the turbines are arranged in series.
Similarly, U.S. Pat. No. 4,674,284 to Kronogard et al. teaches a combustion engine having two turbines connected in series, of which one drives the compressor and the other transfers its output to the engine mechanically. Kronoberg et al. teaches that the turbines and the compressor are mounted at the same side of the engine. Again, the thrust output is dissipated as the energy produced by the combustion travels from turbine to turbine, because the turbines are arranged in series. In the gas turbine engine taught by Kronogard et al., the combustion of high velocity, high pressure gas mixture from the combustion chamber cannot be simultaneously and equally directed to the three turbines to generate maximum thrust because the turbines are arranged in series.
Similarly, U.S. Pat. No. 4,038,818 to Snell teaches a gas turbine for aircrafts having two compressors and two turbines arranged in flow series. The arrangement of the turbines in series does not maximize the thrust output because energy is dissipated as the combustion of high velocity, high pressure gas mixture from the combustion chamber travels from the first turbine to the second turbine.
Accordingly, there is a need for a gas turbine engine that can maximize thrust output by employment of multiple turbines that are not arranged in series.
There is a need for a gas turbine engine having at least two turbines arranged to receive the combustion of high velocity, high pressure gas mixture from the combustion chamber simultaneously.
There is a need for a gas turbine engine having at least two turbines arranged in an opposite configuration to receive the combustion of high velocity, high pressure gas mixture from the combustion chamber simultaneously such that the gas mixture is expelled in the same direction to maximize thrust output.
The present invention is directed to a gas turbine engine having at least two turbines that are mounted opposite to one another. The turbines are not connected in series. Instead, the turbines are mounted on opposite sides of the combustion chamber, such that the combustion of high velocity, high pressure gas mixture from the combustion chamber can be simultaneously and equally directed to both turbines to generate maximum thrust.
SUMMARY OF THE INVENTION
This invention is directed to a gas turbine engine. In an embodiment of the gas turbine engine as described herein, the gas turbine engine is generally comprised of a compressor, a combustion chamber, and at least two turbines. The compressor communicates with the combustion chamber, partitioned by a rotator, which separates the “cold” section of the compressor from the “hot” section of the combustion chamber. In turn, the combustion chamber communicates with two turbines mounted on opposite sides of the combustion chamber. The two turbines are coaxially mounted on two turbine shafts that are connected to a gear shaft regulator centrally located in the combustion chamber. The gear shaft regulator controls the rotation of the turbine shafts, which are capable of independent clockwise and counterclockwise rotation.
According to a preferred embodiment of the invention, the compressor is vertically mounted above the combustion chamber. The vertical compressor has an inlet located at an upper end of the compressor and an outlet located at a lower end of the compressor, such that air received by the inlet moves downwardly through the compressor to the outlet. The outlet of the compressor is connected to a rotator, which in turn is connected to the combustion chamber. The rotator separates the compressor from the combustion chamber. The rotator is mounted to a vertical rotator shaft that runs centrically through the compressor. When the rotator shaft is rotated, it moves the rotator, which allows the combustion chamber and turbines to be rotated to adjust the direction of thrust from the turbines.
More particularly, the combustion chamber is located between a first turbine and a second turbine. The first turbine is opposite to the second turbine. The two turbines are coaxially mounted on two turbine shafts, with the first turbine and second turbine being mounted for independent rotation on the turbine shafts.
The first turbine is comprised of an assembly of radial turbine blades housed in a first turbine body. The first turbine body extends in a first direction from the combustion chamber and has a nozzle at its distal end.
The second turbine housing is comprised of an assembly of radial turbine blades housed in a second turbine body. The second turbine body extends in a second direction from the combustion chamber that is opposite to the first direction of the first turbine body. The second turbine body is divided into two ducts. A first duct bends to one side of the second turbine body and extends substantially parallel to the axis of the turbine shaft in the first direction. The first duct has a first duct nozzle. A second duct bends to the other side of the second turbine body and extends substantially parallel to the axis of the turbine shaft in the first direction. The second duct has a second duct nozzle.
Ambient air is received in the compressor where it is compressed to high pressure. The compressed air is mixed with fuel and ignited in the combustion chamber to produce high pressure, high velocity gas. The resulting pressurized gas mixture is directed simultaneously to the first turbine and the second turbine on opposite sides of the combustion chamber. The turbines turn on their respective turbine shafts. The first turbine rotates a first turbine shaft in a first direction (e.g. clockwise) and the second turbine rotates a second turbine shaft in a second direction (e.g. counterclockwise).
The high pressure, high velocity gas from the turbines is expelled through the nozzles. The gas that is directed through the first turbine flows in a first direction and is expelled through a first nozzle in the first direction (downstream). Because the second turbine is oppositely mounted to the first turbine, the gas that is directed through the second turbine flows in a second direction that is opposite to the first direction. The gas is then redirected by the ducts and expelled through the first duct nozzle and second duct nozzle in the first direction.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of an embodiment of the invention.
FIG. 2 is a top view of an embodiment of the invention.
FIG. 3 is a side view of an embodiment of the invention.
FIG. 4 is a side view of an embodiment of the invention showing the nozzles with downward thrust.
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1 , the gas turbine engine ( 10 ) comprises a compressor ( 20 ), a combustion chamber ( 30 ), and at least two turbines ( 40 , 50 ). A rotator shaft ( 60 ) extends centrically through compressor ( 20 ). A rotator ( 70 ), mounted to rotator shaft ( 60 ), separates compressor ( 20 ) from combustion chamber ( 30 ). A gear shaft regulator ( 80 ), located in combustion chamber ( 30 ), is mounted to rotator shaft ( 60 ). A first turbine shaft ( 90 ) mounts to one side of gear shaft regulator ( 80 ) and a second turbine shaft ( 100 ) mounts to the other side of gear shaft regulator ( 80 ), with first turbine shaft ( 90 ) and second turbine shaft ( 100 ) being coaxial to one another and perpendicular to rotator shaft ( 60 ). First turbine shaft ( 90 ) and second turbine shaft ( 100 ) are capable of independent rotation. A first turbine ( 40 ) is mounted on the first turbine shaft ( 90 ) and a second turbine ( 50 ) is mounted on the second turbine shaft ( 100 ).
The compressor ( 20 ) has an inlet ( 22 ) and an outlet ( 24 ). In a preferred embodiment of the invention as shown in FIG. 1 , the compressor ( 20 ) is centrally mounted above the combustion chamber ( 30 ), though one of ordinary skill in the art would recognize that the compressor ( 20 ) can be oriented in any number of ways with respect to the combustion chamber ( 30 ). As shown in FIG. 1 , the outlet ( 24 ) of compressor ( 20 ) connects with rotator ( 70 ) and communicates with combustion chamber ( 30 ).
Air is received in inlet ( 22 ) and travels downward through compressor ( 20 ) towards outlet ( 24 ). As air travels through compressor ( 20 ), it is compressed to high pressure. The compressed air enters the combustion chamber ( 30 ), where it is mixed with fuel and ignited by an ignition means (not shown) in the combustion chamber ( 30 ) to produce high pressure, high velocity gas. The resulting pressurized gas mixture is directed to a first turbine ( 40 ) and a second turbine ( 50 ) on opposite sides of combustion chamber ( 30 ).
The first turbine ( 40 ) is connected to a first side of combustion chamber ( 30 ). A second turbine ( 50 ) is connected to a second side of combustion chamber ( 30 ) that is opposite to the first side of combustion chamber ( 30 ) as shown in FIG. 1 . Ignited gas from combustion chamber ( 30 ) is directed separately to first turbine ( 40 ) and second turbine ( 50 ). When the ignited gas from combustion chamber ( 30 ) is directed to first turbine ( 40 ), it motivates first turbine ( 40 ) to generate a force (F 1 ) in a first direction (d 1 ). When the ignited gas from combustion chamber ( 30 ) is directed to second turbine ( 50 ), it motivates second turbine ( 50 ) to generate a force (F 2 ) in a second direction (d 2 ) that is opposite to first direction (d 1 ).
In a preferred embodiment of the invention as shown in FIG. 2 , the second turbine ( 50 ) is further comprised of a turbine housing ( 52 ) with at least two ducts ( 54 , 56 ). Combustion chamber ( 30 ) connects to turbine housing ( 52 ). Turbine housing ( 52 ) connects to first duct ( 54 ). The first duct ( 54 ) has a first section ( 54 a ) extending from turbine housing ( 52 ) in second direction (d 2 ) and a second section ( 54 b ) continuing from first section ( 54 a ) that is turned reversely to extend in first direction (d 1 ). Turbine housing ( 52 ) also connects to second duct ( 56 ). In a mirror configuration of first duct ( 54 ), second duct ( 56 ) has a first section ( 56 a ) extending from turbine housing ( 52 ) in second direction (d 2 ) and a second section ( 56 b ) continuing from first section ( 56 a ) that is turned reversely to extend in first direction (d 1 ).
Ignited gas from combustion chamber ( 30 ) is directed to second turbine ( 50 ), where it enters turbine housing ( 52 ), travels through the two ducts ( 54 , 56 ), and exits in first direction (d 1 ) along with the gas from first turbine ( 40 ).
First turbine ( 40 ) and second turbine ( 50 ) have movable nozzles for expelling the ignited gas in variable directions. First turbine ( 40 ) has nozzle ( 110 ) as shown in FIG. 2 . Second turbine ( 50 ) has nozzle ( 120 ) on first duct ( 54 ) and nozzle ( 130 ) on second duct ( 56 ). Nozzles ( 110 , 120 , and 130 ) are adjustable to direct thrust from the ignited gas in variable directions as shown in FIG. 3 and FIG. 4 .
This invention is not to be limited by the embodiment shown in the drawings and described in the description, which is given by way of example and not of limitation, but only in accordance with the scope of the appended claims. | A gas turbine engine comprising a compressor, a combustion chamber, and at least two turbines mounted oppositely to the combustion chamber, such that the gas turbine engine is capable of generating multidirectional thrust. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a Continuation of co-pending U.S. patent application Ser. No. 13/012,402, entitled “Polyolefins Having Reduced Crystallinity”, filed Jan. 24, 2011, which is a Continuation in Part of and claims priority to U.S. application Ser. No. 12/813,131, entitled “Crystallinity Reducer”, filed Jun. 10, 2010, which claims priority to U.S. Provisional Patent Application 61/185,832, entitled “Crystallinity Reducer”, filed Jun. 10, 2009, each of which are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
The thermodynamic, structural and mechanical properties of polyolefins depend strongly on the type, content and distribution of defects generated during synthesis. In the last two decades, the spectrum of new polyolefin materials has undergone an exponential expansion due to the development of metal coordination catalysts with properties changing from those of highly-crystalline thermoplastics to plastomers and elastomers. The materials that have been developed, which range from statistical random copolymers to stereo-bulky elastomers, exemplify the ability of new synthetic strategies to tailor structures and properties of polyolefins by a suitable choice of the coordination catalyst precursor. The availability of such a wide spectrum of polyolefins has led to significant improvements in the approaches taken to characterize their molecular microstructure, which remains a main determinant of their physical properties. Ethylene α-olefin copolymers, polypropylene homopolymer and propylene α-olefin copolymers synthesized with single-site metallocene catalysts (early metal catalyst) serve as models to predict properties of polyolefins with randomly distributed defects.
Polyolefins (isotactic or syndiotactic) are highly crystalline polymers. Polyolefins result from the polymerization of an olefin (a linear or branched hydrocarbon with at least a double bond). Typical olefins are ethene, propene, 1-butene, 3-methyl pentene, 1-hexene . . . etc. For many applications that require increasing tear and impact properties or those with the need of more transparent, more flexible and ductile materials, defects or 1-alkene comonomers are added to the polyolefin backbone to decrease crystallinity.
A new family of polypropylenes (PPs), a type of polyolefins, has been synthesized by living polymerization with late metal catalysts (see for example Cherian, A. E.; Rose, J. M.; Lobkovsky, E. B.; Coates, G. W. J. Am.. Chem. Soc. 2005, 127, 13770-13771). These polymers are structurally distinct from PPs synthesized with early metal catalysts. Late metal catalysts enable chain-walking events; early metal catalysts do not. Specifically for iPP, the chain-walking mechanism adds (3,1) enchainments and often results in unique multi-monomer, bulky defect microstructures. A living chiral α-diimine Ni(II) catalyst can form isotactic PPs (iPPs) and allow controlled chain walking when activated with methylalumoxane (MAO) in the presence of propylene. An amorphous, regioirregular polymer is produced at high reaction temperatures (T rxn =0° C.) while an isotactic, regioregular polymer is obtained at low reaction temperatures (T rxn =−60° C.). Later modifications to the α-diimine Ni(II) catalyst have yielded isotactic polyolefins at an increased rate of polymerization (see for example Rose, J. M.; Deplace, F.; Lynd, N. A.; Wang, Z.; Hotta, A.; Lobkovsky, E. B.; Kramer, E. J.; Coates, G. W. Macromolecules 2008, 41, 9548-9555).
Enchainment via chain walking is a distinctive feature of polyolefins synthesized with the late metal catalysts resulting in extra CH 2 in the iPP backbone compared to defects generated by inversion or 1-alkene comonomers. The result is a chain straightening due to the extended length of the defect in the backbone, as shown schematically in FIG. 1 . Crystalline polyolefins with defects generated via chain walking have unique properties, such as reduced crystallinity (see for example C. Ruiz-Orta, J. P. Fernandez-Blazquez, A. M. Anderson-Wile, G. W. Coates, R. G. Alamo Macromolecules 2011, 44, 3436-3451.
At present, industry reduces the crystallinity of conventional polyolefins by polymer blending or copolymerization with ethylene, 1-butene, 1-hexene or 1-octene. The novel polyolefins with chain walking defects, when used in industry, will reduce the cost of materials production by eliminating polymer blending or addition and control of a comonomer. Polyolefins with chain-walking defects that lead to chain straightening display reduced crystallinity relative to conventional polyolefins with the same number of defects. The novel polyolefins of the present invention can substitute for present-art polyolefins in a variety of applications, for example, thin films, fibers and molded parts, or any other application that require a lower crystallinity than for the homopolymer or copolymer free of chain-walking defects. The reduced crystallinity makes the polymeric materials with better processability due to their lower melting temperatures, more flexible and more transparent.
SUMMARY OF INVENTION
The invention is directed to identify all possible crystalline polyolefins with reduced level of crystallinity by the use of synthetic methods that generate unique defect microstructures by a chain walking effect. The chain walking effect produces defects in the polymer molecules that are different than those found in analog polyolefins made with present art catalysts. The chain-walking defects that are most effective for reducing the level of crystallinity are those of a successive addition or multimonomer nature. The crystalline polyolefins with properties that will be affected by the presence of chain walking defects are alkene-based homopolymers or copolymers of any length or branch geometry, for example homopolymers or copolymers derived from ethylene, propene, 1-butene, 2-butene, 1-hexene, 2-hexene, 3-hexene, 2-methyl 1-pentene, . . . etc.
In one embodiment, the isotactic polypropylenes (iPPs) are taken as examples of polyolefins undergoing chain-walking In this specific example, the iPPs were synthesized by a late metal catalyst-living nickel α-diimine complexes, specifically, Rac-1 and Rac-4 (see U.S. Pat. No. 7,560,523). Not reported in the claims of this patent is the present new discovery that this iPP (a type of the broad group of novel polyolefins of this claim) contains regio defects characterized by isolated or multimonomer successive groups of (2,1) and (3,1) enchainments produced by a chain walking mechanism. Critical to the present claim is that each (3,1) defect generated by a chain walking effect adds three defect carbons per monomer to the polymer backbone. Each successive (2,1)(3,1) defect adds five defect carbons per 2 monomers, and each (3,1)(1,2)(3,1) defect adds eight defect carbons per three monomers to the backbone. Earlier-generation metallocene iPPs, or random copolymers, have defect units with only two carbons per monomer added to the polymer backbone. Chain straightening and the bulky nature of the defects of polyolefins synthesized by a mechanism involving the chain walking effect limits the crystallinity of the polymers.
To demonstrate the generality of the claim, two series of MAO-activated living nickel α-diimine complexes, with and without cumyl-derived ligands, have been used to catalyze iPP synthesis. The resulting polymers displayed properties with profound differences from those of iPPs and iPP copolymers made by conventional methods: lower melting temperatures and much lower degrees of crystallinity than for homopolymers or any random 1-alkene iPP copolymer (a type of iPP) synthesized with earlier metal catalysts and with matched molar defect composition. Moreover, the iPPs produced by chain walking showed significantly higher contents of the gamma polymorph than any other iPP or random copolymer with a matched molar defect composition. The formation of higher contents of gamma polymorph is a signature of having shorter crystallizable sequences. Compared with polyolefins synthesized with early metal catalysts, any crystalline polyolefin with chain-walking defects of the type that increase the number of backbone carbons per monomer, will have shorter crystallizable sequences and, as a consequence, lower crystallinity
As examples of the novel polyolefins of this invention, the iPPs produced by chain walking exhibited bulky defects made of contiguous defect monomers in controlled contents. The length and content of bulky defects is controlled by reaction temperature and the type of catalyst ligand, as shown in Cherian, A. E.; Rose, J. M.; Lobkovsky, E. B.; Coates, G. W. J. Am. Chem. Soc. 2005, 127, 13770-13771 and Rose, J. M.; Deplace, F.; Lynd, N. A.; Wang, Z.; Hotta, A.; Lobkovsky, E. B.; Kramer, E. J.; Coates, G. W. Macromolecules 2008, 41, 9548-9555. The invention relates to the fact that the bulky defects produce a polymer backbone defect microstructure with shorter crystallizable sequences than those found in conventional polyolefins. For a fixed number of monomer units, longer defects produce polymers with shorter crystallizable sequences, and hence lower crystallinities. Lower crystallinities of the homopolymer or copolymer finds applications restricted for conventional polyolefins.
In a preferred embodiment, the synthesized polyolefins have a molecular weight of 30,000-200,000 Da. For example, this range corresponds to approximately 700-5000 monomers in the case of propene. The number of monomers will depend on the type of polyolefin synthesized if the preferred molecular weight range is held constant.
Rac-1α-diimine catalyst (Rac-1) or a cumyl-derived α-diimine catalyst (rac-4) are examples of late metal catalysts that allow chain-walking and polyolefins with reduced crystallinity compared to analog polyolefins synthesized with Ziegler-Natta or earlier metallocene catalysts. More information about these catalysts (used as examples of catalysts leading to chain-walking defects) is found in Cherian, A. E.; Rose, J. M.; Lobkovsky, E. B.; Coates, G. W. J. Am. Chem. Soc. 2005, 127, 13770-13771 and Rose, J. M.; Deplace, F.; Lynd, N. A.; Wang, Z.; Hotta, A.; Lobkovsky, E. B.; Kramer, E. J.; Coates, G. W. Macromolecules 2008, 41, 9548-9555.
BRIEF DESCRIPTION OF THE DRAWINGS
For a fuller understanding of the invention, reference should be made to the following detailed description, taken in connection with the accompanying drawings, for the case of iPP as an example of the novel polyolefins in which:
FIG. 1 is a schematic depiction of iPP backbones with defects generated by early metal/MAO catalysts and those found in iPP synthesized by late metal/MAO catalysts compared for an equivalent 25 number of monomers. Critical to the present claim is the reduced sequence length between defects in the latter. Reduced sequence length leads to reduced crystallinity.
FIG. 2 is a schematic depiction of the mechanism of defect formation by chain walking in Isotactic Polypropylene, as an example.
FIG. 3 is a schematic depiction of 13 C NMR spectrum of iPP 11.82 as an example. The 26-39 ppm region is expanded in the inset.
FIG. 4 is a schematic depiction of letter designations for pertinent chain defect structures and their 13 C NMR peak assignments for iPP as an example of the novel polyolefins. Note that with respect to the growing chain, and in accordance with scheme 1, consecutive “errors” are listed beginning with the last and ending with the first erroneous insertion.
FIG. 5 is a schematic depiction of 13 C NMR assignments of carbons of iPP with chain-walking defects, as example of the novel polyolefins with chain-walking defects, corresponding to sequences of FIG. 3 .
FIG. 6 is a schematic depiction of defect composition of Poly(propylenes) with (3,1)-associated regio defects.
FIG. 7 is a schematic depiction of Polymerization Conditions of Poly(propylenes) with (3,1)-associated regio defects.
FIG. 8 is a schematic depiction of the effect of polymerization temperature on total defect content (mol %) in iPPs synthesized with Ni(II) catalysts with different ligands are used as examples of the novel polyolefins.
FIG. 9 is a schematic depiction of the content of specific type of defect vs. total defect content (mol %) for iPPs synthesized with rac-1 and rac-4 catalysts.
FIG. 10 is a schematic depiction of percentage backbone crystalline carbons (out of 100 backbone carbons) for (3,1) iPPs of FIG. 6 (squares and triangles) and for analogs control iPPs with (2,1) defects (diamonds). Right scale y shows percentage difference between backbone crystalline carbons for (3,1) iPPs and iPP control. The crystallizable sequence length is reduced in polyolefins synthesized with rac-4, and their crystallinity levels are more depressed.
FIG. 11 is a schematic depiction of DSC endotherms of samples melt crystallized at ambient temperature (23±2° C.), and kept at RT for ˜2 weeks.
FIG. 12 is a schematic depiction of melting temperature-defect composition relations for random propylene 1-alkene copolymers, and for iPPs with chain-walking defects (black symbols). Data for copolymers from K. Jeon, H. Palza, R. Quijada, R. G. Alamo, Polymer, 2009, 50, 832. Earlier metallocene-made homopolymer is also added (diamond). The continuous and discontinuous lines are added only as guides of the variation of experimental data.
FIG. 13 is a schematic depiction of heat flow-defect composition relations for random propylene 1-alkene copolymers, and for iPPs with chain-walking defects, as for FIG. 12 . The continuous lines are added only as guides of the variation of experimental data.
FIG. 14 is a schematic depiction of DSC crystallinity normalized by weight fraction of crystalline monomers vs. defect composition relations for random propylene 1-alkene copolymers, and for iPPs with chain-walking defects. The continuous lines are added only as guides of the variation of experimental data.
FIG. 15 is a schematic depiction of WAXD diffractograms of iPP and 1-alkene copolymers slowly cooled from the melt to ambient temperature. Diffractograms are shown at comparative defect levels of ˜3.5 mol %, 8.5 mol % and ˜10.5 mol %.
FIG. 16 is a schematic depiction of the degree of crystallinity calculated from
WAXD as a function of the total defect content (mol %) for iPPs with chain-walking defects and 1-alkene copolymers.
FIG. 17 is a schematic depiction of the content of crystal in the gamma phase developed as a function of increasing isothermal crystallization temperature. Dashed lines for propylene ethylene (PE) copolymers (from K. Jeon, H. Palza, R. Quijada, R. G. Alamo, Polymer, 2009, 50, 832) and solid lines data for (3,1) iPP.
FIG. 18 is a schematic depiction of the content of crystal in the gamma phase developed as a function of increasing isothermal crystallization temperature. Dashed lines, propylene 1-hexene (PH), and propylene 1-octene (PO) copolymers (from K. Jeon, H. Palza, R. Quijada, R. G. Alamo, Polymer, 2009, 50, 832), solid lines data for (3,1) iPPs.
FIG. 19 is a schematic depiction of crystallite thicknesses as a function of the total defect content (mol %) for iPPs with chain-walking defects and propylene/1-alkene copolymers.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A chain-walking defect occurs in polyolefins synthesized with living α-diimine Ni(II)-based catalysts when the metal center migrates along the growing polymer chain through a series of β-hydride elimination and reinsertion events. Polyolefins with chain-walking defects may present unique bulky defects. In iPPs for example, there may be an isolated (3,1) enchainment, alternating (3,1) and (1,2) enchainments, isolated diads or triads (3,1) enchainments, or such enchainments followed or preceded by (2,1) inversions. In addition, tacticity errors or isolated (2,1) inversions may also be present; the latter occur when a (2,1) inversion resists (3,1) enchainment. A large variety of well-defined bulky defect structures are possible under otherwise controlled conditions by changing the reaction temperature. For example, the mechanism of formation of these regio defect structures in iPP is summarized in FIG. 2 . Chain-walking enchainments of a similar nature may be found in the polymerization of isotactic 1-pentene, and other olefins producing continuous methylene sequences in the backbone with five or more carbons. Here, any defect sequence of any length that exhibits chain-walking enchainments is named a chain-walking associated defect.
As an example of characteristics of the novel polyolefins, a 13 C NMR study of PPs synthesized with C2-symmetric, living α-diimine Ni(II) catalysts rac-1 and rac-4 revealed that both catalysts insert the same types of defects ( FIG. 3 ). The structures corresponding to (3,1)-associated defected sequences and (2,1) threo inversions are shown in FIG. 4 . Here, with respect to the growing chain (chain growth from right to left), consecutive “errors” are listed beginning with the last and ending with the first erroneous insertion. Resonances for the indicated carbons in these structures are listed in FIG. 5 . Each carbon type is designated according to the terminology given by Carman et al. (Carman C. J.; Harrington R. A.; Wilkes C. E. Macromolecules 1977, 10, 536-544) where S, T and P refer to secondary (methylene), tertiary (methine) and primary (methyl) carbons respectively, and the Greek subscripts refer to the distance a given carbon is from a neighboring branched methane.
Isolated (3,1) insertions, or defects of type (a), are characterized by resonances corresponding to methylenes, S αδ (a1=37.4) ppm and S βγ (a2=27.5 ppm), and methane, T βδ (a3=30.8 ppm). The best resolved resonance corresponding to the alternating (3,1)(1,2)(3,1) insertion, or defect of type (b), is methine T δδ (b1=33.2 ppm). Successive (3,1)(3,1) insertions, or defects of type (c), introduce seven adjacent methylenes in the backbone with three clearly identifiable resonances in NMR spectra, S βδ (c2=27.3 ppm), S γδ (c3=30.3 ppm) and S δδ (c 4=29.9 ppm). The resonance at 24.5 ppm has been associated with Sββ from a sequence of three adjacent methylenes. Such a sequence is generated in defects of type (d), or . . . (1,2)(3,1)(2,1)(1,2) . . . additions that occur when the second of two consecutive (2,1) inversions is isomerized. The reverse possibility, a defect of type (e), is also plausible and was included in the schemes given by McCord et al. (see McCord, E. F.; McLain, S. J.; Nelson, L. T. J.; Arthur, S. D.; Coughlin, E. B.; Ittel, S. D.; Johnson, L. K.; Tempel, D.; Killian, C. M.; Brookhart, M. Macromolecules 2001, 34, 362-371). This type (e) defect appears absent in iPP made with catalysts Rac-1 and rac-4. Isolated (2,1) threo additions of two conformational diastereoisomeric forms [defects of types (f) and (f′)] are also found in the region 14-16 ppm. The content of erythro (2,1) inversions, if any, is negligible since basically no resonances were found in the 17-18 ppm and 42 ppm regions in any of the spectra.
The content of each type of defected sequence is calculated from the averaged intensity of carbons that belong to a specific defect over the total propylene molar intensity (TPI).
TPI= I (CH 3 )+ S βγ ( a 2 )/2+2 *T δδ +[( S δδ +S γδ )/3+ S γδ /2)]+ S ββ +( P αβ +P αγ )/2 [1]
In Equation [1], I(CH3) corresponds to the NMR signal intensity in the methyl region (area from 19 to 23.5 ppm). Enchained monomer units free of the methyl group are also added to compute the total monomer intensity. These are the isolated (3,1) defect (added as a2/2); the two (3,1) units of the alternating (3,1)(1,2)(3,1) defect, because the CH 3 of the middle unit is included in the I(CH3) region; the resonances of two units from the (3,1)(3,1) successive insertions; the (3,1) unit from the (3,1)(2,1) additions and the isolated (2,1) defects have chemicals shift in the 14—16 ppm region and are therefore outside the I(CH3) area.
Accordingly, the molar fraction of each type of defected sequence over all monomer units is given as:
Isolated
3
,
1-isertion
=
S
βγ
/
2
TPI
=
a
2
/
2
TPI
[
2
]
In Equation [2], only the resonance of the central methylenes are considered to contribute to isolated (3,1) insertions. This is due to overlapping of a1 carbons with other resonances, and the lack of resolution between methines that flank≧4 consecutive methylenes (T βδ ).
Alternating
(
3
,
1
)
(
1
,
2
)
(
3
,
1
)
insertions
=
T
δδ
TPI
=
b
1
TPI
[
3
]
Successive
(
3
,
1
)
(
3
,
1
)
insertions
=
(
S
γδ
)
/
2
TPI
=
(
c
3
)
/
2
TPI
[
4
]
(
3
,
1
)
(
2
,
1
)
insertions
=
S
ββ
TPI
=
d
2
TPI
[
5
]
Isolated
2
,
1
threo
insertions
=
(
I
14
-
16
ppm
)
/
2
TPI
=
(
f
2
+
f
4
+
f
2
′
+
f
4
′
)
/
2
TPI
[
6
]
Stereo
=
I
21.05
/
2
TPI
[
7
]
For all iPPs, S δδ /S γδ was close to 2, indicating a low probability of successive (3,1) insertions longer than two. The molar composition of each type of defect, based on polymers 100 monomers long, is shown in FIG. 6 for the two series of iPPs studied.
The regiochemistry of iPPs with chain walking defects shows interesting catalyst-type dependence. FIG. 7 shows an increase in molecular weight for an increase in reaction temperature. This indicates enhanced catalytic activity with temperature. A progressive increase in the total defect content is evident as temperature increases for both catalysts. There are, however, large differences in the content of defects generated by each catalyst at a fixed temperature ( FIG. 8 ). At the lowest temperatures, ≦−50° C., both catalysts insert about the same low level of defects, whereas ≧−50° C. the cumyl-derived catalyst (rac-4) is more isoselective, inserting many fewer defects than rac-1. The difference in the content of defects generated remains if the content of defective monomers is evaluated vs. reaction temperature instead of defects of types (a-f).
Differences in the activity of each catalyst with respect to the insertion of a particular type of defect are analyzed in FIG. 9 . The content of each type of defect for both catalysts is plotted over the total defect content. The variation in defects (b), (c) and (f) is similar for both catalysts. The major differences are found for defects (a) and (d). For a fixed overall defect content, iPPs synthesized with rac-1 contain more isolated (3,1) enchainments and have negligible amounts of defects of type d. By contrast, iPPs synthesized with rac-4 have a very large number of defects of type d, about 35% of all defects in these iPPs. Therefore, since the rate of iPP polymerization by rac-4 is high, fewer (2,1) defects are generated, and those generated have less time to undergo isomerization to (3,1). A subsequent (2,1) unit can then be added with high probability to undergo (3,1) enchainment, producing a defect of type d. On average, runs of continuous isotactic sequences in rac-4 iPPs are shorter than in rac-1 iPPs because of the greater content of defects of type d in rac-4 iPPs.
A difference in length and number of backbone crystalline carbons is found between rac-1 and rac-4 catalysts. While rac-4 is a more efficient catalyst than rac-1 to polymerize iPP, (rac-4 produces higher molar mass iPPs at the same reaction temperature and time), on average, the defects generated by rac-4 lead to shorter crystallizable sequence lengths compared to those generated by rac-1 ( FIG. 10 ).
Melting Temperatures
The influence of the concentration of total defects on the melting behavior was determined by DSC on specimens that were melt-pressed and kept at room temperature for about two weeks. FIG. 11 shows the endotherms for both (3,1) iPP series compared with the endotherms of propylene ethylene random copolymers (PE) in the same defect range, synthesized with a metallocene catalyst in a prior work. A direct comparison with PEs is first made due to the similarity of the chain-walking effect, at least apparently, to the addition of ethylene units. Both add ethylene runs to the backbone. Furthermore, the addition by a metallocene catalyst of the ethylene unit and by the living catalyst of the (3,1) enchainment are expected to follow random statistics consistent with a site-control polymerization. Thus, (3,1) iPPs can be treated as random copolymers where the a, b, c, d, f and stereo defects are co-units disrupting the isotactic chain regularity as do the ethylene units in the PE copolymer. Comparing the shape of the endotherms of FIG. 11 , It was concluded that except for a more pronounced aging (indicated by a melting peak at ˜40° C.), and the presence of a middle additional shoulder in the lower defect range of rac-4 iPPs, the melting traces of (3,1) iPPs and PEs are very similar.
The major difference with PEs are lower melting temperatures and more prominent aging peaks in (3,1) iPPs, all indicative of less crystalline materials than PEs at equivalent defect composition.
The peak melting temperatures (Tmp)-composition relations of (3,1) iPPs are comparatively shown in FIG. 12 with data for random propene 1-alkene copolymers. For a direct comparison, the evaluation is carried out on the basis of point defects (X B ), defined as a single defect monomer or a multi-monomer defect run bonded on either side by non-defect monomer runs, over the total monomer units. Here, in addition of PEs, data for propylene 1-butene (PB), propylene 1-hexene (PH) and propylene 1-octene (PO) are also shown. The data for copolymers are from Jeon K, Chiari Y L, Alamo R G. Macromolecules 2008; 41:95-108 and from K. Jeon, H. Palza, R. Quijada, R. G. Alamo, Polymer, 2009, 50, 832. Prior to melting all copolymers were subjected to the same thermal history as for (3,1) iPPs. Differences in melting temperatures among the copolymers at a fixed composition are known to be due to differences in the partitioning of the co-unit between crystalline and non-crystalline regions. PBs melt at the highest temperatures because the comonomer participates in the crystallites at the highest content, thus, their crystallizable sequences are the longest. The ethylene unit is also able to co-crystallize with the propylene units, but at a lower extent than is the 1-butene co-unit; hence, the PE melting temperatures are lower than PBs, yet they are higher than for matched PHs and POs. Since the co-units of all POs and PHs with <13 mol % 1-hexene are rejected from the crystallites, their crystallizable sequences are shorter, and their melting temperatures significantly lower. Rac-1 and rac-4 iPP melt at lower temperatures than copolymer due to their shorter crystallizable sequences. The difference in melting increases with increasing concentration of (3,1) defects.
Degree of Crystallinity
FIG. 13 provides an analysis of the variation of the heat of fusion of (3,1) iPPs in a conventional plot where the x axis is X B (moles of point defects per 100 moles of mononer units). The data for random 1-alkene copolymers from K. Jeon, H. Palza, R. Quijada, R. G. Alamo, Polymer, 2009, 50, 832 are also shown comparatively. At a fixed X B content it is found in FIG. 13 the same variation of ΔH with type of co-unit as found for Tmp in FIG. 12 . PB and PE exhibit higher heat of fusion due to the accommodation of the co-units in the crystallites and the concomitantly large concentration of crystalline sequences that participate in the crystallization process. Clearly, (3,1) iPPs lose crystallinity at a much greater rate than PO or PHs with matched defect composition.
The impact of the (3,1) units on crystallinity calculated from the heat of fusion (ΔH/209) is displayed comparatively with values for PH and PO copolymers in FIG. 14 ; thus, the behavior of co-units rejected from the crystalline regions are directly compared. Here, the DSC-based weight fraction crystallinity values are normalized by the weight fraction of crystalline units (fw) to account for the difference in weight of the 1-hexene and 1-octene co-units and the (a)-(f) defect units. Clearly, even after this normalization, a large difference in crystallinity remains. For example, crystallinity drops from 0.40 to about 0.35 at the lowest defect content, and decreases from 0.19 for PO to ˜0.03 in (3,1) iPPs at a 14 mol % defect level, or 85% decrease in crystallinity.
Further evidence of the drastic decrease of crystallinity level of (3,1) iPPs in reference to copolymers with non-crystallizable co-units was obtained from crystallinities derived from WAXD patterns. Selected sets with about the same defect content in a range of ˜3, ˜8 and ˜10 mol % were comparatively studied. The WAXD patterns are shown in FIG. 15 for samples that were slowly cooled from the melt to ambient temperature at ˜2° C./min. In addition to evidences from the WAXD patterns for lower crystallinity of (3,1) iPPs compared to PO and PH, especially at the ˜10 mol % defects, there are also differences in polymorphic behavior within each set. The crystallinity levels obtained after subtraction of the amorphous pattern are given in FIG. 16 . A large crystallinity decrease with respect to values of PH and PO copolymers remains, similarly as found for DSC crystallinities. (3,1) iPPs develop about half of the copolymer's crystallinity at ≧10 mol % defects.
Polymorphism and Crystallite Thicknesses
Extensive studies of iPPs and random 1-alkene copolymers synthesized with metallocene catalysts have demonstrated that the presence of defects in the iPP chain favor the formation of the γ (orthorhombic) polymorph over the more common α (monoclinic) phase. Polypropylenes with increasing defects randomly distributed have shortened crystallizable sequences and develop higher contents of the γ phase. Random iPP copolymers with co-units excluded from the crystal lattice, such as PH (<13 mol %) and PO copolymers, have the same average length of crystallizable sequences, hence, they develop the same content of γ phase. It is also known that the γ 0 phase is favored at higher crystallization temperatures (see for example, Alamo R G, Kim M-H, Galante M J, Isasi J R, Mandelkern L. Macromolecules 1999; 32:4050-64. Hosier I L, Alamo R G, Esteso P, Isasi J R, Mandelkern L. Macromolecules 2003; 36:5623-36. De Rosa et al. Macromolecuels 2002, 35, 3622, De Rosa C, Auriemma F, Ruiz de Ballesteros O, Resconi L, Camurati I. Chem Mater 2007; 19:5122-30).
For homopolymers, and random copolymers it was found that the maximum content of gamma crystals scales inversely proportional to the log of the average length of isotactic sequences (Niso). Since Niso for (3,1) iPPs is lower than for matched random PO and PH copolymers, it is of interest to test if (3,1) iPPs form higher contents of gamma crystals as expected. For these comparative polymorphic studies, the inventors focus on isothermally crystallized rac-1 (3,1) iPPs. With increasing crystallization temperature, the content of gamma phase is compared with data for propylene ethylene copolymers in FIG. 17 and with data for PO and PH copolymers in FIG. 18 . In the figure, the data for the copolymers are indicated as discontinuous lines in the figures, and the symbols are data for rac-1 iPPs. Clearly, in the whole range of defect concentration, (3,1) iPPs develop much higher contents of gamma phase than any 1 -alkene random copolymer with a matched defect content.
Due to the partial accommodation of the ethylene monomer in the crystal, the crystallizable sequence lengths of matched PEs are longer than for (3,1) iPPs, hence, the large difference in gamma content with the behavior of PEs in FIG. 17 is expected. Furthermore, FIG. 18 gives evidence for the fact that (3,1) iPPs also develop higher contents of gamma phase than PH and POs regardless of the exclusion of the co-units (comonomer or chain-walking defects) from the crystallites. This behavior points out that not only have (3,1) iPPs shortened crystallizable sequences than PEs, but the isotactic sequence lengths of (3,1) iPPs are also shorter than for PH and PO copolymers with matched defect composition.
Crystallite thicknesses obtained from SAXS long periods corrected with the crystallinity fraction derived by WAXS, are given in FIG. 19 for slowly cooled specimens. Below ˜4 mol %, the crystallite thicknesses are very similar, however, the influence of blocky defects and the extra backbone carbon from (3,1) insertions displaces the crystallite thicknesses to increasingly thinner values as the overall content of chain-walking defects increases. Hence, the reduction of the crystallizable sequence length in iPPs with chain walking, compared to matched random copolymers, affects crystallite thicknesses in a manner that follows the decrease of melting points measured by DSC.
EXAMPLES OF SYNTHESIS METHODOLOGIES AND CHARACTERIZATION TECHNIQUES
Example I
Poly(Propylene) Synthesis
The diimine-based catalysts used to make the two series of poly(propylenes) analyzed, rac1 and rac 4.
Example II
Propylene Polymerization, FIG. 6 , Entry 6-10
In a glovebox, a 6 ounce (180 mL) round-bottom Laboratory Crest reaction vessel
(Andrews Glass) was charged with toluene (25 mL) and a solution of MMAO-7 (2.4 mL, 4.6 mmol). The solution was cooled to −78° C. and the appropriate mass of propylene was condensed into the vessel. The reaction mixture was then allowed to equilibrate to the desired temperature. After 10 minutes, the complex (17 μmol) was injected as a solution in 2 mL of dry, degassed CH2Cl2. The polymerization was quenched with methanol (10 mL). The reaction mixture was then precipitated into copious acidic methanol (5% HCl(aq)) and the resulting suspension stirred overnight. The polymer was isolated, dissolved in hot toluene, filtered over celite/silica/alumina, precipitated with methanol, isolated again and dried to constant weight in vacuo at 60° C.
Example III
Propylene Polymerization, FIG. 6 , Entries 4 and 5
In a glovebox, a 6 ounce (180 mL) round-bottom Laboratory Crest reaction vessel (Andrews Glass) was charged with toluene (25 mL) and a solution of MMAO-7 (2.4 mL, 4.6 mmol). The solution was cooled to −78° C. and propylene (15 g) was condensed into the vessel. The reaction mixture was then allowed to equilibrate to −55° C. After 10 minutes, complex 3 (0.016 g, 17 μmol) was injected as a solution in 2 mL of dry, degassed CH2Cl2. An aliquot was taken from the reaction mixture via canula using an overpressure of 30 psig propylene after 6 hours. The polymerization was quenched with methanol (10 mL) after 48 hours. Both the aliquot and the final reaction mixture were precipitated into copious acidic methanol (5% HCl(aq)) and the resulting suspensions stirred overnight. Both polymers were isolated, dissolved in hot toluene, filtered over celite/silica/alumina, precipitated with methanol, isolated again and dried to constant weight in vacuo at 60° C.
Example IV
Propylene Polymerization, FIG. 6 , Entries 11-18
In a glovebox, a 6 ounce (180 mL) round-bottom Laboratory Crest reaction vessel (Andrews Glass) was charged with toluene (25 mL) and a solution of MMAO-3A (2.5 mL, 4.6 mmol). The solution was cooled to −78° C. and an appropriate mass of propylene was condensed into the vessel. The reaction mixture was then allowed to equilibrate to the desired temperature. After 10 minutes, complex 5 (0.018 g, 17 μmol) was injected as a solution in 2 mL of dry, degassed CH2Cl2. The polymerization was quenched with methanol (10 mL). The reaction mixture was then precipitated into copious acidic methanol (5% HCl(aq)) and the resulting suspension stirred overnight. The polymer was isolated, dissolved in hot toluene, filtered over celite/silica/alumina, precipitated with methanol, isolated again and dried to constant weight in vacuo at 60° C.
Characterization Techniques
1 H and 13 C NMR spectra of polymers were recorded using a Varian Unitylnova (600 MHz) spectrometer equipped with a 10 mm broadband probe operating at 135° C. and referenced versus residual non-deuterated solvent shifts. The polymer samples were dissolved in 1,1,2,2-tetrachloroethane-d2 (10 wt %) in a 5 mm O.D. tube, and spectra were collected at 135° C. For quantitative proton decoupled 13 C analysis, the spectra were collected either in the same Varian Unitylnova (600 MHz) spectrometer with inverse gated decoupling using the TYCO-25 decoupling sequence, a 30° excitation pulse width, 2.0 s acquisition time, and 30 s relaxation delay. Selected iPPs were also recorded at 120° C. in a 10 mm probe using a Varian spectrometer with a frequency of 700 MHz on 1H. The conditions to obtain the latest spectra were as follows, a 90 degree pulse, an acquisition time adjusted to give a digital resolution between 0.1 and 0.12 Hz, at least a 10 second pulse acquisition delay time with continuous broadband proton decoupling using swept square wave modulation without gating during the entire acquisition period. The spectra were acquired using time averaging to provide a signal to noise level adequate to measure the signals of interest. Samples were dissolved in tetrachloroethane-d2 at concentrations between 10-15 wt % prior to being inserted into the spectrometer magnet. Spectra were referenced by setting the mmmm methyl signal to 21.83 ppm. Carbon multiplicity was determined in the same 700 MHz spectrometer using DEPT (distorsionless enhancement by polarization transfer) experiments.
Molecular weights (Mn and Mw) and polydispersities (Mw/Mn) were determined by high temperature gel permeation chromatography (GPC). Analyses were performed with a Waters Alliance GPCV 2000 GPC equipped with a Waters DRI detector and viscometer. The column set (four Waters HT 6E and one Waters HT 2) was eluted with 1,2,4-trichlorobenzene containing 0.01 wt % di-tert-butyl-hydroxytoluene (BHT) at 1.0 mL/min at 140° C. Data were calibrated using monomodal polyethylene standards (from Polymer Standards Service). The polymerization conditions and molecular weights are listed in FIG. 6 .
The original powders were placed on rectangular 10×5×0.25 mm stainless steel frames and sandwiched between thin Teflon© films by melt compression in a Carver press at 180-200° C. (5 min, 1380 KPa). The plates were then taken a room temperature and left at ambient conditions for at least two weeks prior to the first DSC melting. Since some of the iPPs have slow crystallization kinetics at room temperature, a relatively long aging allows comparison of the melting behavior among the series at a stage when most of the iPP crystalline structure has evolved. Non-isothermal melting and crystallizations (10° C./min) were carried out using a differential scanning calorimeter Perkin Elmer DSC-7 under nitrogen flow. Temperature and heat calibrations were performed with indium as standard. Isothermal crystallization were carried out either in the DSC or in controlled temperature baths. To maximize heat transfer, the DSC was operated in conjunction with an intracooler and under dry nitrogen flow. In the DSC experiments, the films were melted at 180° C. for 3 minutes and cooled at 40° C./min to the required crystallization temperature.
WAXD and SAXS diffractograms were obtained at ambient temperature on samples that were previously isothermally crystallized either in the DSC or in thermostated baths using a Bruker Nanostar diffractometer with IμS micro-focus x-ray source, and equipped with a HiStar 2D Multiwire SAXS detector and a Fuji Photo Film image plate with Fuji FLA-7000 scanner for WAXD detection. SAXS profiles were calibrated with silver behenate and WAXD patterns with corundum, both standards were obtained from Bruker. The peak assignments for α and γ phase followed those given by Brückner and Meille (Brückner S.; Meille S. V. Nature (London) 1989, 340, 455) and Turner-Jones (Turner-Jones A.; Aizlewwod J. M.; Beckett D. R. Makromol. Chem. 1964, 75, 134).
The fractional content of the γ form was calculated, after subtraction of the amorphous halo from the areas of the reflection at 2θ=20.1° characteristic of γ form and the reflection of a form at 2θ=18.8°, as Aγ/(Aγ+Aα). Peak fitting to mixed Gaussian and Lorentzian shapes was carried out with GRAMS. Crystallinity content derived by WAXD was evaluated from the x-ray powder diffraction profiles by the ratio between the crystalline diffraction area and the total area of the diffraction profile.
The thermodynamic and structural properties of iPPs with chain-walking defects, as examples of the novel polyolefins, have been comparatively studied in reference to control random iPP copolymers with comonomers excluded from the crystalline regions, such as the PH and PO copolymers. On a customary molar point defect composition based on 100 monomers, iPPs with chain-walking defects are found to melt at lower temperatures and display a dramatic depression of crystallinity at defect levels of 8-15 mol %. These features, coupled with lower crystallite thicknesses and enhanced contents of iPP crystallites in the gamma phase, are associated with a shortening of isotactic sequence lengths, caused by the bulky nature of most defects, compared with random copolymers. Chain-walking with (3,1) enchainment defects decrease the level of crystallinity of iPPs at a much faster rate than do any of the more common defects found in Ziegler-Natta or early metallocene made iPPs, or propylene random 1-alkene copolymers. Any other polyolefin with chain-walking defects that add extra backbone carbons per monomer will display similar depression of crystallinity.
It will be seen that the advantages set forth above, and those made apparent from the foregoing 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 matters contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. The invention applies to any crystalline backbone polyolefin with random chain-walking defects, and entitles a reduction of crystallinity by increasing the length of the defect in terms of number of backbone carbon units. Any materials, which may be cited above, are fully incorporated herein by reference.
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 there between. Relative terminology, such as “substantially” or “about,” describe the specified materials, steps, parameters or ranges as well as those that do not materially affect the basic and novel characteristics of the claimed inventions as whole (as would be appreciated by one of ordinary skill in the art). | The invention is a novel family of polyolefins characterized by chain-walking defects of the type that add extra backbone carbons per monomer. These polyolefins display a large decrease in crystallinity relative to polyolefins known in the art. Specifically, the reduction in crystallinity is much greater than for earlier polypropylenes with a matched content of stereo or 1-alkene type defects. The claimed polyolefins can be an alkene-based copolymer. The defects in the polyolefin backbone are generated by a chain walking mechanism in which three or more carbons per monomer are added to the polymer backbone instead of two, as in conventional polymerization or copolymerization methods of alpha olefins. The novel polyolefins can be used in applications such as plastic wrapping, thin films, co-extrusion layers or molded parts in the absence of polymer blending or copolymerization. The cost of materials production can be reduced. | 2 |
BACKGROUND OF THE INVENTION
The well known vibrator hitherto used for the conventional concrete placing work comprises primarily such an electric motor, so called "double headed motor", that have a motive shaft penetrating through the rotor to project front and rear of the motor and is adapted for the whole body including the motor to become a vibrating body by means of the eccentric weights attached to both ends of the projecting motive shaft. In such vibrator, since the number of rotations of the motor is ordinarily 3000 r.p.m. or so, it is to be speeded up to an extent of 9000 r.p.m. when in vibration by the use of a separately provided frequency converter(s), generally called "vibration amplifier". The motive shaft rotating at such high speed exerts inevitably turning impacts of the eccentric weights directly onto the bearing portions thereof resulting in decreasing the ultimate useful life of the bearing into only 2˜3 months.
SUMMARY OF THE INVENTION
This invention has been primarily directed to extend the useful life of the bearing used for the vibrating shafts as mentioned above, for the purpose of which the present vibrator is characterized by comprising a vibrating shaft having an eccentric weight respectively at its both ends and arranged in the hollow portion of a hollow motive shaft in place of the conventional vibrating motive shaft, and a rotation-transmitting mechanism interposed between the motive shaft and the vibrating shaft to transmit the rotation of the motive shaft to the vibrating shaft in such a manner that both the shafts rotate in the same direction and the latter rotates more speedy than the former. According to such construction, the bearing portions of the vibrating shaft may be undergone far less vibration impacts than that of conventional ones despite of the same vibration amplitude, yet may be elimineted the need for any frequency converters of very high cost used in the conventional vibrators.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary vertical sectional elevation of a preferred embodiment of the invention;
FIG. 2 is a front elevational view of the invention;
FIG. 3 is a front elevational view of the eccentric weight employed in the same;
FIG. 4 is a fragmentally vertical sectional elevation of an another embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the Figures, 1 is a three-phase A. C. motor. 2 is a hollow motive shaft penetrating through the rotor of the motor to project front and rear of the motor, on which front and rear ends an annular transmitting member 3 is respectively fitted fixedly (the member 3 on the rear end is not shown in the Figure; since the elements denoted hereinafter by the reference numerals 4˜36 are in pairs exclusive of part 18 and disposed symmetrically on front and rear, or right and left, sides of the center line X of the vibrator in FIG. 1, the explanation on the rear side ones are omitted) in a concentrical relation with the shaft 2. 4 is a coupling kee. Screwed fixedly into the inner surface of the front end of the transmitting member 3 through a screw 6 is an another annular member 5 in this instance, into inner surface. portion of which a timing belt 7 of an internal gear form is fitted fixedly by such means as adhesion or the like. The timing belt may be ordinarily made of hard elastic material, such as hard rubber or synthetic rubber. 8 is an inscribed gear, or pinion, engaging with the dents 9 of the timing belt 7 to rotate according to the rotation of the belt 7. 10 is a flexible rotation-transmitting shaft which front end is fitted fixedly into a cylinder body 11 fitted fixedly into a hollow shaft 12 of the gear 8 through a spline 13. The shaft 12 of the gear 8 is carried, through ball-bearings 14, on a carrying body 15 supported on the housing 17 of the vibrator with securing bolts 16. 18 is a vibrating shaft arranged concentrically in a running fit into the hollow portion of the hollow motive shaft 2 through ball-bearing 19, to the end of which an eccentric weight 20 is attached through an annular mounting member 21 screwed onto the front end of the vibrating shaft. 22 is a securing screw of the mounting member. The eccentric weight 20 is, in this instance, composed of a main body 23 and an eccentric adjusting plate 24 attached to the body 23 in a justaposed relation by a securing bolt 25 penetrating through in a loose fit an arc-shaped aperture 26 formed in the adjusting plate 24, to be screwed into the main body 23. The adjusting plate 24 is mounted turnably on the annular mounting member 21 and adapted to turn according to the relative movement of the bolt 25 along the arc-shaped aperture 26. Thus, loosening the bolt 25 and securing it again after suitable turning of the adjusting plate 24 enable the eccentric weight to adjust its eccentricity which results in the desired vibration effect being obtainable at any time. 27 is an aperture formed in the housing 17 and used for turning the adjusting plate 24 and the bolt 25 from the outside of the housing. 28 is a stoper flange of the bolt 25. 29 is a coupling cylinder fitted fixedly onto the rear end of the flexible shaft 10, which base portion is screwed into the screw portion 30 formed in the innermost portion of the hollow portion of the vibrating shaft 18 to accomplish the rotation transmission of the shaft 10 and 18. 31 is a bolt coupling the vibrator with the body undergoing vibration (not shown). 32 is a ball-bearing for the motive shaft 2. 33 is a oil plug for the ball-bearings 14. 34 are ring packings for oil. 35, 36 are O rings.
While, in the aforegoing embodiment, the rotation-transmitting means between the motive shaft and the vibrating shaft are disposed respectively front and rear sides of the motor, it may be equipped only one side thereof, i.e. either front or rear side thereof, as shown in FIG. 4. In the Figure, the right hand portion showing the configuration of the vibrator has an identical construction with the right hand sectional portion of FIG. 1. In the Figure, 32' is a ball-bearing for a motive shaft 2', 19' is a ball-bearing for a vibrating shaft 18', 20' is an eccentric weight, 21' is an annular mounting member of the eccentric weight. In these elements, 32', 19' and 20' may be the same as those of 32, 19 and 20 in FIG. 1 respectively, while the front portions of the shafts 2', 18' become naturally the same things respectively as the front portions of the shafts 2, 18 in FIG. 1.
In operation, as the motive shaft 2 of the motor starts at 3000 r.p.m. and the flexible transmitting shaft 10 rotates according to the shaft 2 at an increased speed of 9000 r.p.m. by virtue of the engaging transmission of the inscribed gear 8 and the timing belt 7, the vibrating shaft 18 turning integrally with the shaft 10 goes to rotate in the same direction as the shaft 2 which results in the actuation of the eccentric weights 20 and so high vibration of the whole body of the vibrator. Thus, the vibrator will be able to afford a desired vibration to the object to be vibrated if secured to the object by the bolt 31.
As will be understood from the aforegoing explanation, since the vibrating shaft 18 is journalled on the motive shaft 2 rotating at 3000 r.p.m. to rotate in the same direction thereas at 9000 r.p.m., the bearing 19 goes to undergo only the turning impacts of the eccentric weights produced in the time that the shaft 18 rotates at 9000-3000=6000 (r.p.m.) despite the vibration amplitude derived from the same shaft running at 9000 r.p.m. In consequence, it will be evident that the bearing portions of the vibrating shaft have the advantage of undergoing far less turning impacts owing to the eccentric weights than do the conventional ones which have been directly subjected to the same produced at 9000 r.p.m. of the motive shaft which may extend so much the useful life of the vibrator.
Besides, since the rotation-transmitting mechanism between the motive shaft and the vibrating shaft may be provided with the annular timing belt of the internal gear form and the inscribed gear engaging thereto and the flexible transmitting shaft, the vibrating shaft and the motive shaft may rotate in the same direction at such speed as the former higher than the latter under assurance of the certain transmission of rotation without any trouble. It will be noted that any other transmitting mechanisms, such as ordinary gear transmission, would be very difficult to use in this event because of their complication and the damage owing to the vibration.
Such an additional effect of the invented vibrator may be further mentioned that since the vibrator of the invention does not require the use of the conventional high cost frequency converters, it offers the possibility of so much cost saving. | There is disclosed a vibrator equipped with a hollow motive shaft penetrating through a rotor of an electric motor to project front and rear of the motor and a vibrating shaft arranged in the hollow portion of the motive shaft in concentric and rotatable relations to rotate in the same direction as the motive shaft at a higher speed than the same through a rotation transmission mechanism interposed between said two shafts. | 1 |
BACKGROUND OF THE INVENTION
FIELD OF THE INVENTION
[0001] The invention relates to a method for fabricating patterned layers made of silicon dioxide on process areas disposed perpendicularly or at an inclination to a substrate surface.
[0002] In semiconductor process technology, planar process areas disposed horizontally with respect to a substrate surface are patterned by photolithographic methods in conjunction with selective etching techniques. During the processing of integrated circuits, reliefs with a pronounced topography are produced on the substrate surface. Such a relief also has surfaces that are perpendicular or at an inclination to the substrate surface. In the course of further miniaturization (shrinking) of the integrated circuits, the need arises also to pattern vertical or inclined process areas in order to differentiate functionally the structures in their vertical extent. Examples thereof are the deep trench capacitor, the stacked capacitor, and vertical transistor configurations. Patterning reliefs in a direction perpendicular to the substrate surface is not directly possible by using photolithographic methods.
[0003] By way of example, if, in the fabrication of a trench capacitor, only sections of the sidewalls of a trench that are disposed perpendicularly to the substrate surface are to be covered with a layer made of silicon dioxide, in order to form a collar at the upper end of the trench, the procedure hitherto has been that the trench is firstly filled with a filling material in the lower region, which is to remain without a covering by the layer made of silicon dioxide. A layer made of silicon dioxide can then be produced on the uncovered sections of the sidewalls of the trench. Afterward, the filling material can be removed in order that the sidewalls are uncovered again in the lower section of the trench.
[0004] In detail, the procedure is such that firstly a trench is introduced into the substrate and a dielectric is deposited over the whole area on the sidewalls of the trench. The trench prepared in this way is filled with a filling material, for example polysilicon, and the filling material is subsequently etched back to an extent such that that section of the sidewall on which the layer made of silicon dioxide is to be deposited is uncovered again. A layer made of silicon dioxide is then deposited, for example by using a CVD method (CVD=chemical vapor deposition). The layer made of silicon dioxide is subsequently etched anisotropically in order to remove portions of the layer that are disposed on the filling material, while the layer remains unchanged at the sidewalls of the trench. The remaining space can subsequently be filled with polysilicon, for example, in order to produce an electrical connection between the inner electrode of the trench capacitor and a transistor.
[0005] If the intention firstly is to fabricate the collar of the trench capacitor in order, for example, to be able to selectively process the lower sections of the trench, the procedure is such that firstly an etching stop layer, for example a nitride layer, is deposited over the entire area of the relief. The relief is subsequently filled with a suitable filling material, for example with polycrystalline silicon, and the filling material is etched back down to a depth corresponding to the sections of the sidewalls on which the layer made of silicon dioxide is to be deposited. The etching stop layer is then removed in the uncovered sections of the sidewalls and the silicon dioxide is deposited or produced thermally on the uncovered areas. The silicon dioxide is subsequently etched anisotropically in order to remove sections of the silicon dioxide layer that are disposed on the surface of the filling material. In this case, the silicon dioxide remains on the vertical sidewalls. The filling material is removed and, as a final step, the etching stop layer is completely removed.
[0006] Plasma enhanced chemical vapor deposition methods (PECVD) are discussed in addition to the above-described methods for fabricating a collar for a trench capacitor. In this case, thin layers are produced on surfaces of a relief; the thickness of these layers, which are on surfaces that are at an inclination or perpendicular to the substrate surface, decreases with increasing depth. In this way, it is thus possible, proceeding from the substrate surface, to cover sections of the sidewalls of a trench with a silicon dioxide layer without covering the lower sections of the trench with a filling material. However, the run-off of the layer produced in the depth can only be controlled with difficulty in these methods. Furthermore, such layers have very great differences in thickness between an end point in the depth of the substrate and a region near the substrate surface.
[0007] Equally, during a diffusion-limited deposition of silicon dioxide by using tetraethyl orthosilane (TEOS), the silicon dioxide grows on surfaces that are perpendicular or at an inclination to the substrate surface at a rate that decreases relative to the relief depth. As a result, the layer thickness of the silicon dioxide thus produced decreases in the direction of the relief depth.
[0008] The lower termination of the silicon dioxide layer in a trench can be established significantly more accurately if a non-conformal ALD method (ALD=atomic layer deposition) is used for the deposition. In ALD methods, the precursor compounds are deposited in a self-limiting manner. To that end, firstly reactive groups are provided on the substrate surface, with which groups, a first precursor compound can react chemically and is thereby chemisorbed on the substrate surface. Once a monolayer of the first precursor compound has formed, the reaction stops because there are no longer any free reactive groups available on the substrate surface. Once excess first precursor compound has been pumped away, a second precursor compound can then be introduced, which can react with reactive groups provided by the first precursor compound. A second monolayer produced from the second precursor compound thus forms in a self-limiting manner. If the first and second precursor compounds are then introduced alternately, a layer of silicon dioxide can be produced for example from Si(NCO) 4 or CH 3 OSi(NCO) 3 as first precursor compound and H 2 O or O 3 as second precursor compound, the thickness of the layer being determined very precisely and being constant over its entire extent. If the chemisorption proceeds in a diffusion-controlled manner, for example when producing a layer made of silicon dioxide in trenches having a high aspect ratio, the monolayer grows proceeding from the upper edge of the sidewall of the trench, that is to say the substrate surface, in the direction of the lower end of the trench. If the chemisorption of the precursor compound is terminated before a complete monolayer has formed, the extent of the layer can be restricted to the upper sections of the trench. The advantages of the non-conformal ALD method are opposed by the disadvantage that long process times have to be accepted if layers having a relatively large thickness are to be produced.
[0009] R. G. Gordon et al. (MRS Spring Meeting 2002) report on a “catalytic” growth of a silicon dioxide layer, layer thicknesses of up to 120 Å per cycle being achieved. In this case, firstly trimethylaluminum is chemisorbed on a substrate surface. Afterward, tris(tert-butoxy)silanol is added to the substrate surface, a chain growth of a siloxane commencing. Subsequent crosslinking of the siloxane chains results in the formation of a layer made of silicon dioxide.
[0010] The previously known methods for fabricating patterned silicon dioxide layers on process areas disposed perpendicularly or at an inclination to a substrate surface thus either encompass a combination of deposition and etching processes. That is, the prior-art methods are very complicated, or they produce layers made of silicon dioxide with a non-uniform thickness whose extent into the depth of a trench can only be determined in an imprecise manner. Although the non-conformal ALD method makes it possible to fabricate uniform silicon dioxide layers whose extent can be controlled in a defined manner, the non-conformal ALD method is very time-consuming to carry out.
SUMMARY OF THE INVENTION
[0011] It is accordingly an object of the invention to provide a method for producing vertical patterned layers made of silicon dioxide that overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type and that makes it possible, in a simple manner and in periods of time suitable for an industrial application, to produce a patterned layer made of silicon dioxide having an substantially uniform layer thickness on process areas that are at an inclination or perpendicular to a substrate surface, the layer, proceeding from the substrate surface, being intended to extend only as far as a predetermined coverage depth.
[0012] With the foregoing and other objects in view, there is provided, in accordance with the invention, a method for fabricating patterned silicon dioxide layers on process areas disposed perpendicularly or at an inclination to a horizontal substrate surface. In a first step, a substrate is provided in a process space. The substrate includes a relief with process areas disposed perpendicularly or at an inclination to the substrate surface. Next, a starter layer with leaving groups that can be substituted by hydroxyl groups are produced on sections of the process areas that extend from the substrate surface down to a specific coverage depth of the relief. Next, tris(tert-butoxy)silanol is added to the substrate. A layer of silicon dioxide is grown selectively on the starter layer.
[0013] The method according to the invention utilizes the above-described “catalytic” growth of a silicon dioxide layer with the use of tris(tert-butoxy)silanol as reactive compound in order to achieve a sufficient layer thickness growth within periods of time suitable for an industrial application. Furthermore, the extent of the silicon dioxide layer is determined by the fact that a starter layer is provided on the process areas only in the sections in which a layer growth is to take place. The starter layer has groups that can be substituted by the hydroxyl group of tris(tert-butoxy)silanol. If tris(tert-butoxy)silanol is added to the relief, it is therefore bonded only on the sections of the process areas on which leaving groups are provided, whereas the tris(tert-butoxy)sila-nol is not bonded in the other sections. Therefore, it is possible to use the tris(tert-butoxy)silanol in an excess, so that a uniform layer thickness growth takes place on the entire section of the process areas that is defined by the starter layer. The tris(tert-butoxy)silanol is generally fed to the substrate surface as a gas; the concentration of the tris(tert-butoxy)silanol is chosen as far as possible to be high enough that the reaction does not proceed in a diffusion-controlled manner. Because of this, a rapid growth of the siloxane chains is achieved and a silicon dioxide layer that has an substantially uniform layer thickness over its entire extent is obtained. Because the reaction is generally carried out at elevated temperature, the siloxane chains are rapidly crosslinked to form a silicon dioxide layer.
[0014] Thus, in contrast to the diffusion-controlled vapor-phase deposition methods, the method according to the invention yields a uniform thickness of the layer over the entire extent of the silicon dioxide layer. Moreover, the method determines the termination of the silicon dioxide layer in a very precise manner by limiting the extent of the starter layer. The method significantly shortens the process times required for fabricating a silicon dioxide layer of a specific thickness compared to the non-conformal ALD method.
[0015] The growth of the siloxane chains or the growth of the silicon dioxide layer decreases as the reaction duration advances. It is assumed that the tris(tert-butoxy)silanol molecules firstly have to diffuse through the newly produced layer as far as the starter layer in order then to be incorporated into the siloxane chains. As the layer thickness of the layer produced increases, the duration required by the tris(tert-butoxy)silanol molecules for diffusion increases, so that the reaction is slowed. It is favorable, therefore, to produce a starter layer anew at specific time intervals, i.e. when the growth of the layer has fallen to a specific value. Afterward, the growth of the layer is continued by feeding in tris(tert-butoxy)silanol. Thus, the above-described first step of providing a starter layer and the second step of depositing a silicon dioxide layer from tris(tert-butoxy)silanol are preferably performed successively a number of times one after the other. The above described first and second steps thus in each case produce a cycle. The number of cycles that are performed for fabricating the silicon dioxide layer is determined by the desired thickness of the layer in this case. In this case, the starter layer is preferably embodied such that it has the same extent over all of the cycles, so that the lower termination of the silicon dioxide layer can be clearly delimited.
[0016] The starter layer is preferably produced by chemisorption of a reactive component, the quantity of the reactive component that forms the starter layer in the process space being restricted to a quantity less than that required for complete coverage of the process areas.
[0017] In this embodiment, the method according to the invention utilizes an effect as is also utilized in the non-conformal ALD method, in order to produce a layer only on sections of a process area. Given a diffusion-controlled reaction implementation, the covering of the process areas with the reactive component takes place beginning at the upper edge of the perpendicular or inclined process areas and continues in the direction of the lower edge of the process area. The covering of the perpendicular or inclined process areas thus begins at the substrate surface and continues in a manner directed into the depth of the relief. Therefore, a complete layer of the reactive component results in the upper regions of the relief facing the substrate surface, while virtually no deposition of the reactive component is effected in lower regions. An intervening transition region, in which a register gradient is present, has only a small extent relative to the typical relief depth. Such a directed systematic covering of a relief from the substrate surface in the direction of the relief depth results if the reactive component has a low desorption coefficient and is offered in a reduced quantity with respect to a quantity required for complete coverage.
[0018] If the reactive component has a low desorption coefficient, then the probability of an already adsorbed molecule of the reactive component being removed again from the layer, that is to say desorbed, is very low. If a reactive component having a low desorption coefficient, corresponding to a high sticking coefficient, is provided in the course of producing the starter layer, then a relief provided on a substrate surface is covered progressively from the substrate surface into the depth. Apart from a short transition region, the coverage is effected completely and with a uniform layer thickness in this case.
[0019] The reactive component is preferably formed in such a way that it can react with groups, for example hydroxyl groups, provided on the process area. The reactive component can thereby be chemically bonded on the process area, with the result that a monolayer of the chemically bonded reactive component is obtained. In this case, the reactive component is formed in such a way that, after the reaction with groups provided on the process areas, leaving groups are still maintained which can be displaced by the hydroxyl group of the tris(tert-butoxy)silanol. The fabrication of the starter layer thus inherently corresponds to the procedure known from the non-conformal ALD method.
[0020] The non-conformal deposition of the starter layer obviates the need to mask sections which are not intended to be covered by the silicon dioxide layer, for example by these regions of the relief being filled with a filling material. The fabrication of the patterned silicon dioxide layer can thereby be simplified to a significant extent.
[0021] Given predetermined process parameters, the accuracy with which a predetermined coverage depth can be achieved depends on the total area of the starter layer that is to be covered. The larger the total area to be covered, the less the dependence of the coverage depth on fluctuations in the quantity of reactive component fed or the duration of the deposition of the reactive component. The higher the density of the structures disposed on the substrate surface, the larger the area of the starter layer which is to be covered with the reactive component becomes as well, since the relief is patterned increasingly more finely and more densely in the horizontal extent and increasingly functional structures are realized at vertical surfaces. Thus, the number of trench capacitors per unit area rises in memory chips, for example, as the storage capacity increases. The accuracy with which the lower edge of a collar made of silicon dioxide can be produced thus rises as the density of the trench capacitors disposed per unit area in a memory chip increases.
[0022] It is important for carrying out the method according to the invention that the extent of the starter layer from the substrate surface into the depth of the substrate can be restricted to a lower value than the maximum depth of the relief. If the starter layer is produced by non-conformal deposition of the reactive component, the quantity of the reactive component may be restricted by way of the quantity of the reactive component that is fed to the process space.
[0023] In this embodiment of the method according to the invention, the quantity of the reactive component that is fed to the process space is thus restricted such that it does not suffice to completely cover the process areas. After the reactive component has been fed into the process space, the vertical or inclined process areas are systematically covered from the substrate surface in the direction of the relief depth, the deposition of the reactive component coming to a standstill as a result of the increasing depletion of the atmosphere in the process space, so that the starter layer covers the perpendicular or inclined process areas only incompletely. After the starter layer has been formed, residues of the reactive component that are still present in the process state can be pumped away or the process space can be flushed with an inert flushing gas. Afterward, as described above, tris(tert-butoxy)silanol is introduced in order to grow a silicon dioxide layer on the starter layer.
[0024] The metering of the quantity of the reactive component that is fed to the process space can be controlled very precisely if the quantity of the reactive component that is fed to the process space is metered by liquid injection. The reactive component vaporizes in the process space or an injection chamber upstream of the process space and passes as a gas onto the perpendicular or inclined process areas in order to be chemisorbed there.
[0025] In accordance with a further embodiment of the method according to the invention, the quantity of the reactive component is restricted by way of a residence duration of the reactive component in the process space. In this embodiment of the method, the quantity of the reactive component fed to the process space may be chosen to be higher than is necessary for the selective coverage of that section of the process areas which is prescribed by the starter layer. After a specific residence duration, which is chosen in such a way that only an incomplete coverage of the perpendicular or inclined process areas has taken place, excess reactive component is removed from the process space, for example by being pumped away or flushed from the process space using an inert flushing gas. Afterward, tris(tert-butoxy)silanol is once again introduced.
[0026] The adaptation of the method according to the invention to different types of reliefs can also be effected by way of the chamber pressure that prevails during the deposition of the reactive component in the process chamber. Thus, a deposition of a non-conformal starter layer on a shallow relief having structures with low aspect ratios and/or a high proportion of process areas that are inclined with respect to the substrate surface requires, for the same coverage depth, a lower chamber pressure than a deposition on a deep relief having structures with a high aspect ratio. The structures preferably have an aspect ratio of greater than thirty (>30).
[0027] In order to achieve a uniform coverage depth, i.e. a uniform extent of the silicon dioxide layer, over the entire substrate surface even in the case of substrates having a large diameter, the reactive component is preferably added in a manner distributed uniformly over the substrate surface by using a distribution device provided in the process space.
[0028] The reactive component from which the starter layer is produced preferably includes leaving groups, which enables a reaction on the one hand with groups provided on the process are and on the other hand with the hydroxyl group of the tris(tert-butoxy)silanol. Organometallic compounds are preferably used as the reactive component. The ligands of organometallic compounds readily undergo exchange reactions, so that the organometallic compound is bonded to the groups, for example hydroxyl groups, provided on the process area. Since organometallic compounds can generally bond a larger number of ligands, even after the absorption of the organometallic compound on the process area there are still enough ligands available to bond the tris(tert-butoxy)silanol in an exchange reaction. Furthermore, a large number of organometallic compounds are offered commercially, so that they are accessible simply and usually cost-effectively.
[0029] The organic ligands bonded to a central metal atom should readily be able to be exchanged in order to enable a rapid reaction of the organometallic compound with groups that are ready on the process area or with the hydroxyl group of the tris(tert-butoxy)silanol. Therefore, the organometallic compound preferably contains a metal selected from the group formed from Al, Hf, Zr, Ti, Y, La, Ta, Sc, Ce, Pr, Nd, Gd, Sm and Dy. Suitable examples are (Me 2 N) 4 M, M=Ti, Zr, Hf, or β-diketonates M(thd) 3 , M=Y, La. Further examples are Hf tert-butoxide, Hf dimethylamide, Hf ethylmethylamide, Hf diethylamide or Hf(MMP) 4 , Ti(OC 2 H 5 ) 4 or Ti(OCH(CH 3 ) 2 ) 4 .
[0030] Owing to their high sticking coefficient, a trialkylaluminum is preferably used as the reactive component for fabricating the starter layer. The examples of suitable trialkylaluminum compounds are triethylaluminum or trimethylaluminum. Trimethylaluminum is particularly preferred.
[0031] The method according to the invention is suitable, in principle, for the vertical patterning of different types of reliefs. In a particular manner, however, it is suitable for patterning trenches that are formed in a high aspect ratio in a substrate. It is precisely in trenches having a high aspect ratio that the deposition of the reactive component is effected in diffusion-determined fashion in a pronounced systematic manner from the substrate surface. The extent of a collar made of silicon dioxide at that end of the trench that is adjacent to the substrate surface can therefore be embodied with high precision.
[0032] In a particularly preferred embodiment of the method according to the invention, the trenches are formed functionally into capacitors. The method according to the invention enables a dielectric collar made of silicon dioxide to be produced in a simple manner, so that the steps required for fabricating a trench capacitor can be considerably reduced. The trenches that are customarily used for the fabrication of deep trench capacitors usually have an aspect ratio of more than thirty (>30), preferably more than fifty (>50). A further increase in the aspect ratio is expected for the future. An aspect ratio is understood to be the ratio of the extent of the trench into the depth of the substrate, that is to say perpendicular to the substrate surface, to the extent of the opening of the trench at the substrate surface.
[0033] In the fabrication of a collar made of silicon dioxide for a trench capacitor, by way of example, firstly a starter layer is produced from trimethylaluminum by using non-conformal deposition on a section of the process area. The starter layer is subsequently converted into aluminum oxide by reaction with the tris(tert-butoxy)silanol. The aluminum oxide layer has a high trap density, for which reason parasitic transistors may be formed in the completed trench capacitor. The parasitic transistors lead to a premature discharge of the capacitor due to a high leakage current density. Therefore, a covering layer made of silicon dioxide is preferably applied before the deposition of the starter layer at least on the process areas. The covering layer may have a thickness of 1 to 5 nm, for example. Hydroxyl groups are then available for the bonding of the reactive component, for example trimethylaluminum, on the surface of the silicon dioxide layer.
[0034] The covering layer made of silicon dioxide may be produced from SiCl 4 and H 2 O by using a CVD method, for example. However, the covering layer made of silicon dioxide is preferably produced by thermal oxidation. In this case, the entire relief, i.e. the areas that are formed from silicon, is lined with a covering layer made of silicon dioxide.
[0035] Uncovered sections of the covering layer made of silicon dioxide may be removed after the application of the patterned silicon dioxide layer. The covering layer can be removed by using a wet treatment with dilute aqueous hydrofluoric acid, for example.
[0036] Other features that are considered as characteristic for the invention are set forth in the appended claims.
[0037] Although the invention is illustrated and described herein as embodied in a method for producing vertical patterned layers made of silicon dioxide, 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.
[0038] The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] FIGS. 1 A- 1 D are schematic illustrations showing a possible mechanism of the production of a layer made of silicon dioxide; and
[0040] FIGS. 2 A- 2 G show a schematic sequence of method steps that are performed in the method according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0041] Referring now to the figures of the drawings in detail and first, particularly to FIG. 1 thereof, there is shown a mechanism for the growth of a silicon dioxide layer as proposed by R. Gordon et al. Disposed on a process area 1 are hydroxyl groups 2 that can react with trimethylaluminum as reactive component. In this case, two methyl groups of the trimethylaluminum are replaced by the oxygen atoms of the hydroxyl groups 2 ; two methane molecules are liberated per molecule of trimethylaluminum. Given an excess of trimethylaluminum, the reaction proceeds until all the hydroxyl groups 2 on the process area 1 have reacted. A monolayer of a starter layer thus forms which, with the methyl groups that are still bonded to the aluminum, has leaving groups for the hydroxyl groups of the tris(tert-butoxy)silanol. Once any excess trimethylaluminum has been removed from the process space, tris(tert-butoxy)silanol is then introduced. The hydroxyl group of the tris(tert-butoxy)silanol reacts with the aluminum atom of the starter layer, the methyl group that has remained on the aluminum in each case being displaced with cleavage of a molecule of methane. If an excess of tris(tert-butoxy)silanol is offered, further tris(tert-butoxy)silanol molecules may be intercalated into the aluminum-oxygen bond, so that a chain lengthening occurs with cleavage of tert-butanol. A repeated intercalation of tris(tert-butoxy)silanol molecules leads to the formation of siloxane chains on the process area 1 . FIG. 1B schematically shows the configuration of these siloxane chains 3 . The chains all have an identical extent. Since the individual tris(tert-butoxy)silanol molecules are in each case intercalated into the aluminum-oxygen bond at the process area 1 , the chain growth is largely insensitive to fluctuations in the concentration of the tris(tert-butoxy)silanol over the process area 1 . The tert-butyl groups bonded to a silicon atom can be cleaved thermally, with cleavage of isobutene and liberation of a hydroxyl group at the silicon. The mechanism is illustrated in FIG. 1C. The liberated hydroxyl group can then attach to a silicon atom of an adjacent siloxane chain, so that a crosslinking of the chains takes place with cleavage of tert-butanol. If hydroxyl groups are liberated in adjacent siloxane chains, the chains can likewise crosslink with cleavage of water. Possible mechanisms for the crosslinking of adjacent siloxane chains are illustrated in FIG. 1D. Finally, a layer made of silicon dioxide is obtained as a result of the increasing crosslinking. Since no more tris(tert-butoxy)silanol can diffuse through the silicon dioxide layer, the chain growth comes to a standstill. If the layer thickness is to be increased further, therefore, a monolayer is produced anew from trimethylaluminum as starter layer, and the layer thickness growth is continued, as described above, by the subsequent introduction of tris(tert-butoxy)silanol.
[0042] [0042]FIG. 2A to FIG. 2E show successive process steps in the fabrication of a collar made of silicon dioxide at the upper section of a trench introduced into a substrate. A substrate 6 including a semiconductor substrate 4 and an auxiliary layer 5 disposed on the semiconductor substrate 4 has a horizontal substrate surface 7 , from which a trench 8 extends into the substrate 6 in a direction perpendicular to the substrate surface 7 as far as a relief depth 9 . The trench wall 10 forms process areas 11 perpendicular to the substrate surface 7 . A coverage depth 12 , up to which the relief formed by the trench 8 is to be covered with a layer of silicon dioxide that is to be formed subsequently, is prescribed between the substrate surface 7 and the relief depth 9 . The coverage depth 12 divides the trench 8 into an upper trench region 13 oriented toward the substrate surface 7 and a lower trench region 14 . In accordance with the trench regions 13 , 14 , upper sections 15 of the process area 11 are disposed between the substrate surface 7 and the coverage depth 12 and lower sections 16 of the process area 11 are disposed between the coverage depth 12 and the relief depth 9 .
[0043] The trench 8 is firstly lined completely with a thin covering layer 17 having a thickness of approximately 2 nm. The covering layer 17 may, for example, include silicon dioxide and be produced by thermal oxidation if the substrate 6 is constructed from silicon. As an alternative, by way of example, it is also possible to employ an ALD or CVD method in order to produce the covering layer 17 made of silicon dioxide from suitable precursor compounds.
[0044] In accordance with the method according to the invention, a starter layer 18 is produced on those sections of the covering layer 17 that are disposed on the substrate surface 7 and the upper sections 15 . Due to the high sticking coefficient of the reactive component, the starter layer 18 grows proceeding from the substrate surface 7 in the direction of the relief depth 9 . The growth of the starter layer 18 in the direction of the relief depth 9 is restricted. By way of example, for this purpose a process quantity of the reactive component is restricted, so that the starter layer 18 grows no further than as far as the coverage depth 12 . The process of depositing the starter layer 18 also can be terminated upon reaching the coverage depth 12 , for example by reactive component that is still present in the process space being pumped away.
[0045] A formation of a starter layer 18 as illustrated in FIG. 2C results in both cases. The starter layer 18 extends as a uniform monolayer above the coverage depth 12 . Virtually no deposition of the reactive component takes place below the coverage depth 12 .
[0046] After the reactive component has been pumped away from the process space, tris(tert-butoxy)silanol is introduced into the process space. In this case, the tris(tert-butoxy)silanol is offered in a concentration at which the formation of a siloxane layer 19 does not proceed in a diffusion-controlled manner. The trench 8 is thus completely filled with gaseous tris(tert-butoxy)silanol. However, a deposition of the tris(tert-butoxy)silanol takes place only in those sections of the process area 11 that are covered by the starter layer 18 . Therefore, the siloxane layer 19 is formed only in the upper section 15 of the process area, whereas no reaction takes place in the lower section 16 of the trench 8 . The siloxane layer 19 thus extends uniformly and with a uniform layer thickness above the coverage depth 12 . No layer thickness growth takes place below the coverage depth 12 .
[0047] The formation of a starter layer 18 in a first process step and afterward the formation of a siloxane layer 19 in a second process step is repeated a number of times, so that the thickness of the silicon dioxide layer formed in the upper section 15 increases to the desired extent. The state illustrated in FIG. 2E is obtained. A silicon dioxide layer 20 has been produced in the upper section 15 of the trench 8 by repeated deposition of a starter layer 18 and of a siloxane layer 19 . After the crosslinking of the siloxane layers 19 , the layer 20 is substantially formed from silicon dioxide, with which are admixed small quantities of aluminum, for example, which have resulted from the starter layer 18 . The silicon dioxide layer 20 typically contains proportions of aluminum ions in the region of approximately 1%. Afterward, the covering layer 17 is removed in the lower section 16 of the trench 8 by etching using dilute hydrofluoric acid and the layer 20 is removed on the substrate surface 7 by anisotropic etching. The construction illustrated in FIG. 2F is obtained. A collar formed from the silicon dioxide layer 20 is disposed in the upper section 15 of the process area 11 or of the trench 8 . The collar extends with uniform layer thickness from the substrate surface 7 as far as a coverage depth 12 . The silicon dioxide layer 20 , which is doped with aluminum ions, for example, is separated from the substrate 6 by a covering layer 17 made of silicon dioxide. The wall of the trench 8 is uncovered again in the lower section 16 of the process area 11 in the region of the trench 8 between the coverage depth 12 and the relief depth 9 . From the construction illustrated in FIG. 2F, a capacitor can then be constructed in a customary manner in further sections, for example by the semiconductor substrate 4 being selectively doped by vapor phase doping in the lower sections 16 . In the application in the fabrication of DT (Deep Trench) DRAM memory cells, the doped region thus produced corresponds to a low-impedance connection of an outer electrode (buried plate). After a dielectric has been deposited in the lower sections 16 , the remaining inner space of the trench 8 can be filled with highly doped polysilicon, for example, in order to obtain a counterelectrode. The schematic construction of such a trench capacitor is illustrated in FIG. 2G. Vapor phase doping has resulted in doped regions 21 in the semiconductor substrate 4 , which form the outer electrode of the capacitor. Disposed on the doped regions 21 is a layer 22 of a dielectric that extends below the collar 23 along the wall. The remaining space is filled with highly doped polysilicon in order to obtain a counterelectrode 24 . The counterelectrode 24 can be connected to a transistor (not illustrated) in subsequent work steps in order to control the charge state of the trench capacitor. | A method is taught for fabricating patterned silicon dioxide layers on process areas disposed perpendicularly or at an inclination to a substrate surface. Firstly, a starter layer having leaving groups is produced by non-conformal deposition of a reactive component. Tris(tert-butoxy)silanol is subsequently added. The addition of the tris(tert-butoxy)silanol leads to the formation of a silicon dioxide layer selectively only on the starter layer. | 2 |
This is a continuation, of application Ser. No. 25,562 filed Apr. 3, 1970 now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a novel and advantageous process of treating heating apparatus using hot water or steam as source of heat such as water and steam baths and especially to a process of treating such apparatus serving for pasteurizing and/or sterilizing victuals or medicines which are packed and water-tightly sealed in glass, plastic, or metal containers.
2. Description of the Prior Art
It is frequently necessary to subject packed goods to a thermal treatment in a water or steam bath. Containers such as metal cans, plastic containers, preserve jars, and the like are, for instance, pasteurized and/or sterilized by heating them to a more or less increased temperature.
Such a thermal treatment in aqueous heating media can be carried out in open containers at atmospheric pressure or in enclosed systems under pressure to effect heating above the boiling point of water or in systems kept under vacuum for a gentle thermal treatment. In many cases the temperatures to which the goods in their containers are heated exceed 100° C. Such a thermal treatment is required, for instance, in the production of sterilized milk and of condensed milk, of canned meat and fish, of preserves of vegetable and fruits, of dietetic food, of medicinal preparations and the like. Thereby, disagreeable side-effects such as corrosion of the containers and of those parts of the apparatus used for the thermal treatment, which are in contact with the aqueous heating medium, i.e. with steam or hot water, are encountered. Furthermore, deposits of the hardness causing salts in the water may be formed on such thermal treatment. These deposits caused by the specific composition and properties of the water used for the thermal treatment, cover the container walls as well as the packing enclosing the sterilized or pasteurized goods. In addition thereto the apparatus used for the thermal treatment are contaminated very frequently by the goods to be heat-treated either due to careless handling of the containers or to their becoming leaky or to breakage of the containers.
It is known to clean cans inserted into an autoclave, by means of a special cleaning agent as this is described, for instance, in "Der Fisch" vol. 3, page 544 (1949). It is also disclosed in German Pat. No. 617,585 to clean the empty heating apparatus by enzymatically removing milk residues. German Pat. No. 694,237 suggests to remove beer and milk scale, for instance, from pasteurizing apparatus by the addition of rather large amounts of a cleaning composition composed of tartaric acid together with smaller amounts of other salts as well as of phosphoric acid. Such scale removing compositions have an acid pH-value and thus are quite corrosive. The cleaning composition is added to remove beer, milk, and other chalk-containing scaly deposits after they have formed in the apparatus.
All these known processes, however, have the disadvantage that they do not prevent corrosion of the apparatus and the containers. Such corrosions are always encountered when using water for the thermal treatment which has a high oxygen content free carbon dioxide or, respectively, has a high content of chlorides, sulfates, and nitrates.
Heretofore, sterilizer autoclaves of different types of construction have been used for the thermal treatment of packed goods. To avoid corrosion, such sterilizer autoclaves have been equipped with anodes to be sacrificed. Another method of avoiding corrosion was the addition of sodium silicates, nitrites, chromates, sulfites, or specific types of mineral oils. However, the results achieved by the installment of such anodes or the addition of anticorrosive agents were rather unsatisfactory. Furthermore, it is evidently not appropriate to use nitrites or chromates when treating containers for victuals.
It is known from the art of water conditioning to prevent formation of calcareous fur or incrustations in aqueous systems by the addition of water soluble polyphosphates together with amino methylene phosphonates in substoichio-metric, so called "inoculating" amounts between about 0.5 mg./l. and about 25 mg./l. and as corrosion protecting agent sodium zinc polyphosphates in inoculating amounts between about 1 mg. of P 2 O 5 /l. and about 10 mg. of P 2 O 5 /l. These additives are added, however, to running water which is exposed, at the most, to a temperature up to 80° C.
SUMMARY OF THE INVENTION
It is one object of the present invention to provide a simple and highly effective process of treating heating systems using hot water or steam as source of heat used for the heat treatment of goods enclosed and water tightly sealed in glass, plastic, or metal containers, and especially for pasteurizing and/or sterilizing victuals or medicines whereby scale formation at and corrosion of the walls of the heating apparatus and systems as well as the containers for the goods are prevented.
Another object of the present invention is to provide compositions to be added to such heating systems using hot water or steam as source of heat in order to prevent or suppress corrosion of and scale deposition at the walls of the heating apparatus and systems as well as the containers for the goods to be subjected to heat treatment.
Other objects of the present invention and advantageous features thereof will become apparent as the description proceeds.
In principle the process of treating aqueous heating systems and apparatus using hot water or steam as source of heat, such as water or steam baths as they are employed for the heat treatment of goods enclosed and water tightly sealed in glass, plastic, or metal containers comprises the addition of amino methylene phosphonic acids, hydroxy alkane diphosphonic acids, hydroxy acids with at least two vicinal hydroxyl groups, or the alkali metal salts of such acids, or mixtures thereof to such aqueous heating systems.
Suitable phosphonic acids or polyhydroxy acids are, for instance, amino methylene phosphonic acids of the following formulas. ##STR1## wherein R 1 is the group of the formula ##STR2## and R 2 is the group of the formula ##STR3## or the group of the formula ##STR4## wherein R 3 and R 4 are hydrogen or the group of the formula ##STR5## x is an integer from 2 to 3, and y is an integer from 0 to 4; or the group of the formula ##STR6## wherein R 5 is hydrogen;
R 6 is alkyl, preferably lower alkyl, and R 5 and R 6 together form alkylene,
R 7 is hydrogen or the group of the formula ##STR7## z is an integer from 0 to 1.
Amino methylene phosphonic acids which are especially useful in the process of treating aqueous heating systems according to the present invention are, for instance, the following acids:
Amino tris-(methylene phosphonic acid),
diethylene triamino penta-(methylene phosphonic acid),
propylene diamino tetra-(methylene phosphonic acid),
ethylene diamino tetra-(methylene phosphonic acid), and others.
1,2-Cyclohexane diamino tetra-(methylene phosphonic acid), and
1-amino methyl cyclopentylamino-(2)-tetra-(methylene phosphonic acid),
and the like compounds have also been found of value.
Hydroxy or amino alkane diphosphonic acids of the following Formula II have also proved to be useful in the process according to the present invention. ##STR8## wherein R 8 is hydroxyl or an amino group, while
R 9 is alkyl with 1 to 8 carbon atoms when R 8 is hydroxyl; or aryl, preferably phenyl, cycloalkyl, preferably cyclohexyl or cyclopentyl, or alkyl with 1 to 10 carbon atoms when R 8 is an amino group. Such compounds are, for instance,
1-Hydroxy ethane-1,1-diphosphonic acid, and others.
Aliphatic polyhydroxy carboxylic acids with two vicinal hydroxyl groups such as
gluconic acid,
tartaric acid,
citric acid
and the like polyhydroxy carboxylic acids are especially useful for the purpose of the present invention.
Furthermore, pentoses and hexoses or polyvalent alcohols such as glycerol or sorbitol may be added to the aqueous systems to be treated according to the present invention in addition to the amino methylene phosphonic acids, hydroxy or amino alkane diphosphonic acids, polyhydroxy carboxylic acids, or other alkali metal salts.
It is, of course, understood that the amount of scale formation and corrosion preventing additive according to the present invention which is added to the aqueous system depends upon the quality of the water employed therein. Its content of hardness causing constituents is of special importance. As an average, addition to 100 l. of water of amounts between about 0.05 g. and about 150 g. of the additive are usually sufficient to produce the desired scale formation and corrosion preventing or suppressing effect.
Combinations of the phosphonic acids with the polyhydroxy acids have proved to be of special value because their anticorrosive effect is superior to that of the two compounds when used alone. Thus the combinations exhibit a pronounced synergistic effect.
A mixture of diethylene triamino pentamethylene phosphonic acid and gluconic acid or sodium gluconate in the proportion of 1:1 has proved to be especially suitable for the purpose of the present invention. Such a mixture is added to the water in an amount between about 0.1 g./100 l. and about 100 g./100 l. and preferably in an amount between about 5 g./100 l. and about 40 g./100 l.
The addition of the above mentioned phosphonic acids and/or hydroxy acids results in the elimination of the hardness causing salts in the water used for heat treatment, in preventing or suppressing corrosion, in providing the metal parts of the apparatus with a protective coating, in removing scale or fur and calcareous incrustations when already formed in the apparatus, and in preventing formation of scale and incrustations on the containers for the goods to be sterilized or otherwise heat treated. Thus fully satisfactory appearance of the packing containers is achieved. The containers keep their perfect and pleasing appearance over a prolonged period of time.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following examples serve to illustrate the present invention without, however, limiting the same thereto.
EXAMPLE 1
The following tests were carried out in upright autoclaves of a capacity of 10 l. of water. The autoclaves were operated at about 4 atm. gauge and at 140° C. They were charged with conventional tin plate cans.
Tap water of the following composition was used for sterilization:
______________________________________Total hardness 17.3° (German degrees of hardness)Hardness due to carbonates 17.3° (German degrees of hardness)pH-value 7.2Chlorides 164.2 mg./l.Sulfates 36.0 mg./l.______________________________________
(a) Autoclave No. 1 was charged with tap water of the above given composition without additive. On sterilizing the cans at 140° C. for 45 minutes, scale formation on the cans and in the autoclave was observed.
(b) Tap water of the above given composition was filled in autoclave No. 2. 5 cc. of a mixture of a 50% aqueous solution of diethylene triamino penta-(methylene phosphonic acid) and a 16% aqueous solution of gluconic acid in the proportion of 1:3, corresponding to 625 mg. of the phosphonic acid and 600 mg. of gluconic acid in 10 l. of tap water, were added. The cans were sterilized at 140° C. for 45 minutes.
(c) Tap water of the following composition was filled in the autoclave No. 3:
______________________________________Total hardness 29.2° (German degrees of hardness)Hardness due to carbonates 17.3° (German degrees of hardness)pH-value 7.1Chlorides 164.2 mg./l.Sulfates 36.0 mg./l.______________________________________
5 cc. of a mixture of a 50% aqueous solution of diethylene triamino penta-(methylene phosphonic acid) and a 16% aqueous solution of gluconic acid in the proportion of 1:1 were added to the water. The amounts of phosphonic acid and gluconic acid added to 10 l. of water thus were, respectively, 1250 mg. and 400 mg.
The autoclaves No. 2 and No. 3 did not show any scale formation and the sterilized cans were free of incrustations and were glossy and shiny.
EXAMPLE 2
The autoclaves No. 1 and No. 2 of Example 1 were used in the following tests. They were charged with tin plate cans containing vegetables. Tap water of the following composition was employed for sterilization:
______________________________________Total hardness 24.4° (German degrees of hard- ness)Hardness due to carbonates 12.2° (German degrees of hard- ness)Chlorides 170.5 mg./l.Sulfates 60.6 mg./l.______________________________________
i.e. a relatively hard water of highly corrosive properties under the sterilizing conditions. Sterilization was carried out at a temperature of 112° C. and a pressure of about 1.5 atm. gauge for about 45 minutes.
(a) The water in autoclave No. 1 did not contain any additive.
(b) 2.5 cc. of a 50% aqueous diethylene triamino pentamethylene phosphonic acid solution corresponding to 1250 mg. per 10 liters of water were added thereto.
(c) Sterilization was effected in autoclave No. 3 under the same conditions and with the same addition of diethylene triamino pentamethylene phosphonic acid but by using tap water of the following composition:
______________________________________Total hardness 10.5° (German degrees of hard- ness)Hardness due to carbonates 8.6° (German degrees of hard- ness)Chlorides 15.2 mg./l.Sulfates 18.0 mg./1.______________________________________
In contrast to test (a) with tap water but without additive the water in tests (b) and (c) which was treated with diethylene triamino pentamethylene phosphonic acid did not show any scale formation in the autoclaves nor any incrustations on the cans. The surfaces of the cans were bright and shiny and were not corroded.
EXAMPLE 3
The tests were carried out in two upright autoclaves No. 1 and No. 2 each containing 10 l. of water. Sterilization was effected by heating at 140° C. and a pressure of about 4 atm. gauge for 120 minutes. Both autoclaves were charged with conventional tin plate cans. The water used for sterilization was tap water of the following composition:
______________________________________Total hardness 17.3° (German degrees of hard- ness)Hardness due to carbonates 17.3° (German degrees of hard- ness)Chlorides 14.2 mg./l.Sulfates 31.0 mg./l.______________________________________
66 cc. of a 16% aqueous solution of gluconic acid corresponding to 9.6 g. per 1.0 l. of water were added to autoclave No. 2.
While considerable scale formation was observed in autoclave No. 1 as well as on the cans with the untreated water, no such scale was formed with the treated water in autoclave No. 2 and on the cans sterilized therein.
When adding, in place of the 16% gluconic acid solution, 4 cc. of a mixture of a 50% aqueous solution of diethylene triamino pentamethylene phosphonic acid and a 14% aqueous solution of sodium gluconate in the proportion of 1:1 to the tap water of the above given composition, i.e. 1000 mg. of the phosphonic acid and 280 mg. of sodium gluconate to 10 l. of tap water and operating under otherwise the same conditions, the autoclave as well as the cans were free of incrustations. The cans had a fully satisfactory, bright, and shiny appearance.
It is, of course, possible to vary the proportions of the phosphonic acids and the gluconic acid or, respectively, its sodium salt in the mixtures added to the water. Especially effective have proved proportions of phosphonic acid to gluconic acid, or respectively, gluconate, between 3:1 and 1:3.
EXAMPLE 4
The autoclaves No. 1 and No. 2 of Example 1 were used in this test. They were charged with vegetable canned in tin plate cans. The water used for sterilization was of the following composition:
______________________________________Total hardness 17.3° (German degrees of hard- ness)Hardness due to carbonates 17.3° (German degrees of hard- ness)Chlorides 15.2 mg./l.______________________________________
5 cc. of a 50% aqueous soluton of nitrilo tris(methylene phosphonic acid) corresponding to 2.5 g. of the phosphonic acid for 10 l. of water were added to the water of autoclave No. 2. Sterilization was effected by heating at 135° C. under a pressure of 1.4 atm gauge for 60 minutes. The cans sterilized in autoclave No. 2 with the treated water did not show any scale formation and incrustation on the cans and in the autoclave in contrast to the cans sterilized in autoclave No. 1 filled with untreated water.
EXAMPLE 5
The tests were carried out in upright autoclaves No. 1 and No. 2, each containing 10 l. of water. They were charged with conventional tin plate cans and sterilized by heating to 130° C. under a pressure of about 1.4 atm. gauge for 90 minutes. The water used in these tests was of the following composition:
______________________________________Total hardness 17.3° (German degrees of hardness)Hardness due to carbonates 17.3° (German degrees of hardness)Chlorides 14.0 mg./l.______________________________________
5 cc. of a 50% aqueous solution of 1-hydroxy ethane-1,1-diphosphonic acid corresponding to 2.5 g. of the phosphonic acid for 10 l. of water were added to the water in autoclave No. 2. It was found that no scale was formed in the autoclave and on the cans sterilized in the treated water while considerable scale formation was observed when sterilization was effected in untreated water.
EXAMPLE 6
The tests were carried out in upright autoclaves No. 1 and No. 2, each containing 10 l. of water. They were charged with conventional tin plate cans and sterilized by heating to 130° C. under a pressure of about 1.4 atm. gauge for 90 minutes. The water used in these tests was of the following composition:
______________________________________Total hardness 35.0° (German degrees of hardness)Hardness due to carbonates 28.0° (German degrees of hardness)Chlorides 150 mg./l.Sulfates 80 mg./1.Nitrates 30 mg./1.pH-value 7.1______________________________________
10 cc. of a mixture of a 50% aqueous solution of diethylene triamino penta-(methylene phosphonic acid) and a 16% aqueous solution of sodium gluconate in the proportion of 1:1 were added to the water in autoclave 2. The amounts of phosphonic acid and sodium gluconate added to 10 l. of water thus were, respectively, 2500 mg. and 800 mg.
In contrast to autoclave 1 and the cans sterilized therein, no scale formation was observed in autoclave 2 and on the cans sterilized therein.
In place of the phosphonic acids and polyhydroxy carboxylic acids used in the preceding examples, there are employed other phosphonic acids and polyhydroxy carboxylic acids and, if desired, other additives in the amounts given in the following examples, while otherwise the procedure as described hereinabove is followed:
__________________________________________________________________________ Proportion of phosphonic acid to poly-ExamplePhosphonic Amount added Polyhydroxy Amount added hydroxy carboxylic OtherNo. acid per 100 l. carboxylic acid per 100 l. acid additives__________________________________________________________________________7 Propylene diamino tetra- 25 g. Tartaric acid 75 g. 1 : 3 --(methylene phosphonicacid)8 1,2-Cyclohexane diamino 3 g. Citric acid 3 g. 1 : 1 --tetramethylene phosphonicacid9 Ethylene diamino tetra- 40 g. -- -- -- --(methylene phosphonicacid)10 1-Aminomethyl cyclo- 70 g. -- -- -- --pentylamino-(2)-tetra-(methylenephosphonic acid)__________________________________________________________________________ | Scale formation as well as corrosion are suppressed by adding amino methylene phosphonic acids, hydroxy alkane diphosphonic acids, amino alkane diphosphonic acids, polyhydroxy acids, their alkali metal salts, or mixtures thereof to the aqueous heating medium of heating systems used for heat treating, such as sterilizing and pasteurizing, goods enclosed in glass, metal, and the like containers. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation patent application of International Application No. PCT/SE2004/000089 filed 22 Jan. 2004 which was published in English pursuant to Article 21(2) of the Patent Cooperation Treaty, and which claims priority to Swedish Application No. 0300777-0 filed 21 Mar. 2003. Said applications are expressly incorporated herein by reference in their entireties.
FIELD OF THE INVENTION
The present invention relates to a method for control of the capacity of an air compressor and a device for performing the capacity test.
BACKGROUND OF THE INVENTION
In vehicle workshops, it is difficult to easily decide when a compressed air compressor incorporated in a vehicle should be exchanged and replaced by a new one. Usually, there are two criteria for exchange. The first is that the compressor shoots out oil into the compressed air. This dirties the air, but does not necessarily mean that the pump capacity is low. Since dirty air can be seen with the naked eye, it is possible to easily and immediately decide whether it is time to change the compressor.
The second criterion is that the compressor is pumping too slowly; that is to say, that the compressor produces too little compressed air per unit of time. This checking of the pump capacity is more complicated and as of yet, there has not been any simple way of gaining a reliable assessment. The checks which have been carried out in workshops have been imprecise and have not been suitable for various types of vehicle. In workshops, the test has been conducted by coupling an external manometer to the compressed air system of the vehicle and then measuring the time it takes for the compressor to raise the pressure to a certain value. This produces only an approximate time value, since it is not possible to adapt the test with regard to sources of error. For example, the test is not adaptable to the fact that different tank volumes ought to give different time values.
Other sources of error are, for example, that the air supply varies if someone climbs into and out of the car during the measurement. The air volume can also be changed by the passage of air to other reservoirs in the vehicle. Attempts have also been made to define “pump-up-time;” i.e., the time it takes when the compressor starts from a rest position until the motor has been run up to a predefined speed and the system has assumed a predefined pressure, but for practical reasons this has not proved successful in the workshops.
Owing to these difficulties in checking the compressor capacity, the compressor is in many cases changed long before its actual working life has expired. On the one hand, this is a waste of resources, and on the other hand, it is unnecessarily expensive to exchange working compressors solely because their capacity cannot be accurately assessed.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a method for checking the capacity of a compressor in a simple and reliable manner. The invention also incorporates a device comprising (including, but necessarily limited to) as few constituent parts as possible for carrying out the check of the capacity of a compressor.
The term “capacity of a compressor” here denotes the quantity of air which the compressor delivers per unit of time at a given compressor speed and counter-pressure.
By virtue of the method prescribed according to the invention, the compressor capacity is able to be checked in a simple and reliable manner. The advantage with this is that it is easy to make the checks in the workshops to determine whether a change of compressor is needed.
According to the method of the present invention, the compressor capacity in the vehicle is checked by air being allowed to flow out from the pressure tank through an opening of known geometry. Following a calculation, the quantity of evacuated air is established. After this, the compressor pumps back up to the initial pressure in the pressure tank. The compressor capacity is obtained by comparing the time it takes for the compressor to pump back up to the initial pressure with the time it takes when an acceptable compressor pumps the same quantity of air.
In an advantageous refinement of the method, the air is allowed to flow out from the pressure tank for a set period. The quantity of evacuated air is calculated. After this, the compressor pumps back up to the initial pressure in the pressure tank and the time it takes to pump this known quantity of air is compared with a time value in order to evaluate the compressor capacity.
In another refinement of the method, the pressure is allowed to drop between two predefined pressures. The time which the pressure takes to drop is measured and the discharged quantity of air is subsequently calculated.
After this, the compressor pumps back up to the initial pressure in the pressure tank. The time it takes to pump this known quantity of air is compared with a reference value in order to evaluate the compressor capacity.
In another advantageous refinement of the method, prior to performance of the capacity check, a check is made that the pressure in the pressure tank lies within a predefined pressure range for a predefined time. This check enables a leakage of air from the compressed air system or to other reservoirs to be detected. Air leakage from the pressure tank renders the capacity check ineffectual.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described in greater detail below with reference to illustrative embodiments shown in the accompanying drawings, and in which:
FIG. 1 is a diagram showing a traditionally controlled compressor system; and
FIG. 2 is a diagram showing an electrically controlled compressor system with a test device.
DETAILED DESCRIPTION
The following described illustrative embodiments of the invention, with refinements, should be regarded only as examples and should by no means serve to limit the scope of protection of the patent claims. In the illustrative embodiments described herein, the same reference numerals refer in the various figures to the same type of component.
A traditional air dryer according to FIG. 1 has a so-called off-line regeneration. The air which is pumped out from a compressor 1 deposits water droplets, which means that the air dryer 7 is exposed to moisture.
Following completion of the compression, the air dryer 7 has to be dried with dry air. The compressor 1 , with incorporated motor 2 , supplies compressed air to the air dryer 7 through a conduit 4 . The air dryer 7 is in turn coupled, by a conduit 5 , to a separate tank 8 , constituting a regeneration tank containing dry air. Coupled to the air dryer 7 by a conduit 6 , via a nonreturn valve 10 , is a pressure tank 3 . In this case, the pressure tank 3 represents the compressed-air-consuming system in the vehicle. When the pressure in the pressure tank 3 has reached a predefined maximum value, a valve 11 on the air dryer is opened in order thereby to reduce the pressure and terminate the pumping.
Should the system also contain a control conduit 9 for relieving the compressor, this conduit, too, is activated. The air in the regeneration tank 8 is thereafter fed back through the air dryer 7 for drying of the drying mass in the air dryer 7 . After this, it is possible to reuse the air dryer 7 . The air dryer 7 has a pneumatic control unit 12 and the air dryer also often incorporates a pneumatic control signal which runs via the control conduit 9 disposed between the air dryer 7 and the compressor 1 . This pneumatic control signal enables the pumping of the compressor to be shut off, so that the pumping of air can be started and stopped in a controlled manner.
An electrically controlled air dryer has a so-called in-line regeneration according to FIG. 2 for the purpose of drying the air, which means that a by-pass coupling 14 is used instead of the regeneration tank used in a traditional air dryer. The by-pass coupling 14 is disposed either in the air dryer 7 or between the pressure tank 3 and the air dryer 7 . In the by-pass coupling there is a valve 13 , which can be opened and can let back air from the tank to the air dryer. The valve 13 is controlled via a wire 20 from an electric control unit 17 , which is either an integral part of the air dryer or a separate control unit. The air dryer 7 is dried by dry air being taken from the pressure tank 3 , after which this dry air is fed back through the air dryer 7 to dry the drying mass in the air dryer 7 until the air dryer has become once again dry.
The method according to the invention can advantageously be used in an electrically controlled air dryer having a so-called in-line regeneration, since a special evacuation of air from the air tank is made on an already existing system. No extra equipment needs to be fitted on the vehicle in order to perform the capacity check on the compressor.
The test device 18 in FIG. 2 is constituted by a control unit 15 coupled to the ordinary control unit 17 of the air dryer. The control unit 15 comprises a processor, memory and suitable input and output circuits which are well known to the person skilled in the art. The control unit 15 is also connected to an instrument panel 16 for displaying generated information concerning the compressor capacity. The compressor is driven by a motor 2 and the speed of the motor is set to a predefined value prior to the start of the test. The compressor pumps air until a predefined pressure Pl is achieved in the pressure tank 3 , after which the compressor is relieved of load. When this value of P 1 has been found to be stable, i.e. air is not leaking out from the system, a quantity of air is evacuated from the pressure tank 3 . This is affected by a valve 13 being held open for a set period, in which the air is allowed to flow out. The air flows out through an opening (not shown) of predefined size. The pressure in the pressure tank is measured as the air is evacuated and, since the diameter of the opening is known, the discharge flow, and hence the evacuated quantity of air, can be calculated. The measurement of the pressure can take place continuously; i.e., analogously throughout the measurement or at regular or irregular intervals. When the evacuation of air has been completed, an instantaneous pressure P 2 is registered by the control unit 15 .
The compressor then refills the pressure tank 3 until the original pressure Pl has been achieved. Once the evacuated quantity of air has been calculated, the quantity of air pumped by the compressor when the pressure in the pressure tank was increased from the pressure P 2 to the pressure Pl is known. The control unit 15 measures the time tl consumed when the compressor increases the pressure from the pressure P 2 in the pressure tank to the original pressure P 1 . The control unit then checks whether this time tl lies within a predefined time range tr. The predefined time range tr is the time consumed when a compressor with acceptable capacity pumps the corresponding quantity of air. Values of tr for different compressor speeds can be stored in a database in the control unit 15 . If the time tl lies outside the predefined time range tr, the control unit 15 generates a error message indicating that the used compressor should be exchanged since its pump capacity is too low. This error message can be shown in an instrument panel 16 forming part of the test device.
In one example, a compressor is fitted on a vehicle. Since the method presupposes that no air consumption occurs during execution of the method, the method is most advantageously carried out after the vehicle has been started and the compressed air system has reached a steady state. The compressor is driven by the engine of the vehicle, which has a preset speed of 1000 rpm. The pressure P 1 is set to a level below the cut-off pressure of the system, for example 11.5 bar. A valve is thereafter held open for a certain period, whereupon the air is discharged through a predefined opening of known geometry. The air flow through the opening is calculated by continuously measuring the pressure in the pressure tank and the evacuated volume is subsequently calculated. This is done by applying a generally known correlation such as Bernoulli's equation. The pressure P 1 in the tank is measured prior to the start of the test. Thereafter, the pressure is measured continuously as air is evacuated for a certain period after which the evacuated quantity of air can be integrated on a forward basis. By letting the air flow out in this way, a method is obtained which is independent of the volume of the pressure tank and it is thus applicable to different types of vehicle and vehicle variants with variously large compressed air volumes. On certain vehicle variants, superstructures can be fitted which do not affect the measuring method.
The principle of measuring how great a volume is discharged from the pressure tank is that the air, for a set period, is fed out from the pressure tank through an opening of specific geometry. If Bernoulli's equation is applied, then evacuated volume is obtained according to:
V=fφdt φ=F (p, d) in which V=evacuated volume (liters) φ=air flow (liters/s), P=the air pressure (Pa) and d=the diameter of the opening (dm).
The method can be initiated, for example, when the vehicle is ready for servicing in a workshop and is connected via a connection 19 to a test apparatus in the workshop (not shown). The compressor capacity is thereafter reported to a service mechanic via the test apparatus.
Another way of initiating the method is for the initiation to take place in a menu system present in the vehicle. In this case, the result is shown in the instrument panel 16 .
Apart from the capacity check being simple to conduct, it is independent of the volume of the air reservoir and is therefore valid for vehicles of different types.
For a twin-cylinder compressor with 700 cc cubic capacity, a reasonable value of tl is, for example, 5 seconds, and tr can be 1.7 times t 1 ; i.e., a deterioration in pump capacity of around 40% for an approved compressor.
In an alternative embodiment, the compressor is driven by a motor 2 and the speed of the motor is set to a predefined value. The higher the chosen speed, the quicker the test can be performed. The compressor pumps air until a predefined pressure P 1 is achieved in the pressure tank. When this value of P 1 has been achieved, a quantity of air is evacuated from the pressure tank 3 . This is done by evacuating air through a predefined opening until a second pressure P 2 in the pressure tank has been achieved and has been registered by the control unit 15 . The time spent on getting the pressure to drop from the pressure P 1 to the pressure P 2 is used to calculate, with the aid of Bernoulli's equation, the volume of the evacuated quantity of air. The compressor pumps the pressure in the pressure tank 3 back up to the original pressure P 1 . The control unit 15 measures the time tl consumed when the compressor increases the pressure from the pressure P 2 in the pressure tank to the original pressure P 1 . The control unit then checks whether this time tl lies within a predefined time range tr. If the time tl lies outside the predefined time range tr, the control unit generates a error message. This error message can be shown in an instrument panel 16 forming part of the test device.
Another refinement of the method includes a check that the first pressure (P 1 ) in the pressure tank 3 lies within a predefined pressure range for a certain set period. A leakage of air from the compressed air system or to other reservoirs can thereby be detected. Air leakage from the pressure tank 3 renders the capacity check ineffectual.
In another advantageous illustrative embodiment, the method can be applied to a compressor forming part of a free-standing air generation unit used, for example, at building sites.
In another refinement, the monitoring can be remote-controlled via the internet or by telephone. This is particularly advantageous with respect to free-standing air generation units, which are often unmonitored. In this case, the test can be realized independently by the system. In this case, the compressor is set to conduct the test at regular intervals, for example each time it is started. The system can call a monitoring center and send error messages and/or a report of the compressor capacity.
Another advantage with the invention is that the capacity check can be realized automatically by an algorithm in the control system ensuring that the test is conducted at programmed regular intervals.
The invention should not be considered to be limited to the illustrative embodiments described above, but rather a host of further variants and modifications are conceivable and considered within the scope of the patent claims. For example, the method is not only applicable to ground vehicles, but also to, for example, airplanes, boats, and the like. As another example, a flow meter may be used at the predefined hole instead of calculating the flow from the pressure tank. | A method and device for evaluating the capacity of a compressor ( 1 ) by air being allowed to flow out from a pressure tank ( 3 ) through an opening of known geometry. Following a calculation, the quantity of evacuated air is obtained. After this, a compressor ( 1 ) pumps back up to the initial pressure in the pressure tank ( 3 ). The compressor capacity ( 1 ) is established by comparing the time it takes for the compressor ( 1 ) to pump back up to the initial pressure in the pressure tank ( 3 ) with the time it takes when an acceptable compressor ( 1 ) pumps the same quantity of air. By the compressor capacity ( 1 ) is here meant the quantity of air which the compressor ( 1 ) delivers per unit of time at a given compressor speed and counter-pressure. | 5 |
The Government of the United States of America has rights in this invention pursuant to Department of Energy Contract W-7405-ENG-48 between the U.S. Department of Energy and the University of California for the operation of Lawrence Livermore National Laboratory.
FIELD OF THE INVENTION
The invention pertains to high speed digital computers, and more particularly to methods and apparatus for performing floating point operations in digital computers.
BACKGROUND OF THE INVENTION
High speed computing normally requires many-fold repetitive arithmetic operations (addition, subtraction, multiplication, division, exponentiation, etc.). An increase in efficiency of one or more of such operations translates directly into proportionate time savings in computer operation. In floating point operations, whereby any numerical operand x (≠ 0) is represented by a unique ordered pair of numbers (e, f) such that e is an integer and f satisfies 1 ≦ |f| < 2 so that x=2 e f, paradoxically, the addition and subtraction operations are more cumbersome than the operations of multiplication, division and exponentiation. Thus, efficiency improvements in floating point addition and subtraction are of special interest.
Bohm, in U.S. Pat. No. 3,315,069, discloses and claims a computer that is constructed to always form the quantity F(a, b, c, d)=(a±b)×c÷d in response to any binary arithmetic input (a, b) or (a, c) or (a, d) or (b, c) or (b, d) or (c, d); with the other two arithmetic inputs being chosen to produce the particular arithmetic result desired. For example, if the difference a-b is desired, the function F and its four inputs become F(a, -b, 1, 1)=(a-b)×1=a-b; and if the quotient a÷d (d≠0) is called for, the function F and its inputs becomes F(a, 0, 1, d)=a/d. Groups of four registers, one containing each of the inputs a, (±)b, c and d, are logically connected so that the result F(a, b, c, d)=(a±b)×c/d is always produced. The inventor notes that time for addition or subtraction in this scheme is substantially longer than addition or subtraction in a conventional approach. And use of floating point numbers would pose further problems and require additional computer time.
Kindell et al disclose and claim computer apparatus for consistently "rounding off" positive and negative numbers in 2's complement representations of floating point numbers, in U.S. Pat. No. 3,699,326. A rounding constant, different for positive and for negative numbers, is added to such numbers for purposes of storage or comparison. The logic used causes consistent round up (round down) to an n-bit number if the actual, untruncated number minus the n-bit truncated number lies closest to or equidistant between the "upper" ("lower") of two adjacent values of the number truncated at the n th bit. No means of forming sums or differences of two floating point numbers is discussed.
Method and apparatus for approximately simultaneous computer computation and processing of coefficients for two Fast Fourier Transform algorithms is disclosed and claimed in U.S. Pat. No. 3,721,812, issued to Schmidt. In one embodiment, the Schmidt invention interlaces two serial streams of appropriate data in a single serial access memory so that two Fast Fourier Transforms may be calculated substantially simultaneously, thus reducing the time normally required for computation of the FFT by approximately 50 percent. However, the invention does not concern simultaneous performance of additions and subtractions of floating point representations of numbers.
SUMMARY OF THE INVENTION
The subject invention is method and apparatus for performing floating point arithmetic operations such as addition and subtraction of two floating point (binary) numbers x A =(2 e .sbsp.A)f A and x B =(2 e .sbsp.B)f B (1 ≦ f A , f B < 2, e A and e B integers), on a computer in a time-efficient manner.
One object is to provide an approach for floating point addition and subtraction that consumes less computer time relative to prior art approaches.
Another object is to provide an approach for performing floating point addition and subtraction simultaneously.
Other objects of the invention, and advantages thereof, will become clear by reference to the detailed description and the accompanying drawings.
To achieve the foregoing objects in accordance with the invention, the conventional three step process of prenormalization, addition, and postnormalization for performing a floating point arithmetic operation is broken up into two parallel two step processes, each two step process essentially eliminating one of the steps of the three step process. The two paths provide the correct answer for the two cases where the exponents are close (exponent difference ≦ 1) or far apart (> 1), respectively. A floating point arithmetic operation is performed simultaneously in both paths, without regard to which condition is actually true, and the correct answer is selected from the results by means of a simple test of three bits of the answer. In the case where the exponents are close (difference ≦ 1), the prealignment step is eliminated since one of the numbers must at most be shifted one bit; the unshifted or one-bit shifted number is selected by means of a multiplexer using a simple test of the lower two bits of the exponents to provide the select signal. In the case where the exponents are far apart (difference > 1 ), the post-normalization step is eliminated since once the numbers have been prealigned and added, the result requires at most a one-bit right or left shift, which can be selected by means of a multiplexer using a simple comparison of three bits of the result to provide the appropriate select signal.
In one preferred embodiment, the first path is implemented by a (short) alignment shift calculator which compares each lower two bits of the exponent and forms the control signals r A =max (0, e B -e A ), r B =max (e A -e B , 0) which in this case are either 0 or 1. The outputs of a pair of two input multiplexers with inputs f A , 1/2 f A and f B , 1/2 f B , respectively, are controlled by the select signals r A and r B , respectively, to provide the appropriate inputs (either unshifted or shifted by one bit) into an adder/subtracter to form the sum f tmp =f A 2 -r .sbsp.A +f B 2 -r .sbsp.B. The sum f tmp is input into a priority encoder which generates the function S=|log 2 |f tmp |. A shifter produces the result f' r =f tmp 2 -S by shifting f tmp by S bits, and an adder produces the result e r '=e max +S.
The second path is implemented by a (full) alignment shift calculator which looks at the entire exponents and forms the control signals r A and r B (which may be >1 in this case). The control signals r A and r B are input to a pair of barrel shifters which shift f A and f B , respectively, for proper prealignment to provide the appropriate input to an adder/subtacter which forms the sum f tmp =f A 2 -r .sbsp.A +f B 2 -r .sbsp.B. By checking three bits of f tmp , the two bits before the point f tmp (1) and f tmp (0) and the bit after the point f tmp (-1), for the presence of a 1, one of three answers can be selected from a four-input multiplexer 1/2 f tmp , f tmp , or 2 f tmp . If none of the bit tests are satisfied (none of the three test bits is a 1) then this indicates that the second path does not provide the correct answer and the first path result, which is the fourth input to the multiplexer, is the correct answer. The bit test also allows the selection of the correct exponent, e max +1, e max or e max -1, formed using adders, if one of the bit tests is satisfied, or the result from the first path if none of the bit tests are satisfied, with the four choices being inputs to a four-input multiplexer.
To perform simultaneous add and subtract in the first path, an exclusive or gate can be added to compare the sign bits of f A and f B and to select the signed inputs, either unshifted or one-bit shifted, from a four-input multiplexer. In the second path, a subtractor circuit is placed in parallel to the adder.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and form a part of the specification, illustrate an embodiment of the invention and, together with the description, serve to explain the principles of the invention.
FIG. 1 is a schematic view of representative prior art apparatus for performing floating point addition.
FIGS. 2 and 3 are schematic views of complementary apparatus, used in combination for performing floating point addition (or subtraction) according to the subject invention.
FIGS. 4 and 5 are schematic views of complementary apparatus, used in combination in simultaneously performing floating point addition and floating point subtraction according to the subject invention with significantly less than twice the hardware required to do either operation individually.
DETAILED DESCRIPTION
The invention provides method and apparatus for improved floating point arithmetic operation. In the prior art, floating point addition/subtraction is basically a three step process of alignment, addition and realignment. The invention shortens the conventional process by essentially eliminating the first or third step. According to the invention the numbers are first compared to determine if the exponents are greatly different or close together. The two cases are processed differently. Depending on the result of the comparison, one of two two-step processes is selected. The operations are performed simultaneously in two parallel independent paths, and the correct answer is selected according to the appropriate criteria from the answers produced in the two paths. If there is a large exponent difference the necessity for the realignment step is eliminated, and the process is essentially that of alignment and addition. If the exponents are close together, then the step of alignment is eliminated and the appropriate process is one of addition and realignment. Thus, by performing an initial comparison, one of the three full steps can be replaced by a much shorter operation which thereby reduces overall process time. This is accomplished by parallel hardware which produces two different answers only one of which is correct, for the two cases, the correct answer being selected by a simple test. The invention can be utilized to perform the operations A+B and A-B in pairs, one through the first two-step process and the other through the second two-step process, the two operations being performed independently in parallel.
This invention decreases the "latency" of certain floating point operations such as addition and subtraction for purposes of high speed computing. The "latency" of an operation is the time elapsed, beginning when an operation is first begun and ending when the immediately following operation that is dependent upon the first operation, is begun. A computer arithmetic operation may have many latencies, one for each possible way in which other operations can depend upon the subject operation. In high speed "number crunching" computer operations, latency is of critical importance, whether or not the machine is rapidly performing a repetitious sequence of arithmetic/logical operations through "pipelining". Thus, design of computer hardware for floating point addition/subtraction with minimal latency and high pipeline rate is very attractive.
A floating point number x is expressed as a pair of numbers (e, f), where the mantissa or fraction f (expressed in binary form) is a p-bit fixed point fraction whose magnitude lies between 1 and 2,
1≦|f|<2 (except for x=0),
and the exponent e, is an integer, with the floating point number x being representable uniquely as x=2 e f. Given two floating point numbers, x A =(e A , f A ) and x B =(e B , f B ), a conventional approach to compute the normalized floating point sum illustrated schematically with reference to FIG. 1, first determines e max =max(e A , e B ) and shifts both x A and x B downward by e max binary places using a full alignment shift calculator and a pair of right shifts to form f A 2 e .sbsp.A -e .sbsp.max and f B 2 e .sbsp.B -e .sbsp.max ; this assures that the exponents are both non-positive. The two modified numbers to form the sum are added in an adder/subtractor
f.sub.tmp =f.sub.A 2.sup.e.sbsp.A.sup.-e.sbsp.max +f.sub.B 2.sup.e.sbsp.B.sup.-e.sbsp.max
and the functions
g.sub.tmp =log.sub.2 |f.sub.tmp |, and
S= g.sub.tmp ,
where g is the largest integer ≦ the real number g are formed by means of a priority encoder which counts leading zeros. The numbers f tmp and g tmp satisfy the condition
|f.sub.tmp |<4,
-∞<g.sub.tmp <2.
The result of the floating point operation is obtained by means of an adder and a full shift of S bits:
e.sub.r =e.sub.max +S,
f.sub.r =2.sup.-S f.sub.tmp,
where (e r , f r ) is the pair of numbers representing the desired floating point sum. Two potentially large shifts must be performed serially in the conventional approach; the first shift initially aligns the operands; and the second shift renormalizes the result of the addition/subtraction operation. These full shifts, performed serially, represent a large fraction of the total latency (elapsed time) of conventional floating point addition and subtraction.
The subject invention provides a new approach, utilizing the fact that computation of the floating point sum (or difference) x A +x B =f A 2 e .sbsp.A +f B 2 e .sbsp.B can be resolved into two mutually exclusive and exhaustive situations, each with a separate approach and corresponding hardware, and each being performable faster than by use of the conventional approach. The difference |e A -e B | is formed in an exponent comparator (not shown). Two independent parallel computations are performed, as shown schematically in FIGS. 2 and 3, respectively, one for each of the two possible situations, and the correct answer is selected by examining the two results.
Situation 1: |e A -e B =0 or 1. The right shift operation, used to implement the usual division by 2.sup.|e.sbsp.A -e .sbsp.B|, is either no shift or a one-place right shift for numbers in binary form; and the shift itself can be determined by looking solely at the lowest two bits of each exponent e A and e B . Only the lowest two bits are checked in the FIG. 2 path, and the calculation is performed as if the exponent difference is less than or equal to 1. The FIG. 2 path has been optimized for this case in terms of minimizing latency of operation. Of course, the test may not be true depending on the higher bits of the exponents. The correctness of the answer is determined by checking the result, as discussed below; it may turn out that the FIG. 3 answer is the correct result, in which case the FIG. 2 answer is rejected.
Formation of the sum (or difference) in this situation may be implemented using the apparatus of FIG. 2 as follows.
Set e.sub.max =max(e.sub.A, e.sub.B);
if e.sub.A =e.sub.B +1, set r.sub.A =0 and r.sub.B =1;
if e.sub.A =e.sub.B, set r.sub.A =r.sub.B =0;
if e.sub.A =e.sub.B -1, set r.sub.A =1 and r.sub.B =0;
or more generically,
set r.sub.A =max(e.sub.B -e.sub.A, 0)=e.sub.max -e.sub.A and
r.sub.B =max(e.sub.A -e.sub.B 0)=e.sub.max -e.sub.B.
The values of r A and r B can only be 0 or 1 (in this case). If |e A -e B |<1, one need only compare the lowest two bits of each exponent to determine e max , r A and r B , which is considerably faster than comparing all bits of e A and e B . The apparatus then forms the following functions and results:
f.sub.tmp =f.sub.A 2.sup.-r.sbsp.A +f.sub.B 2.sup.-r.sbsp.B,
S= log.sub.2 |f.sub.tmp | ,
e'.sub.r =e.sub.max +S,
f'.sub.r =2.sup.-S f.sub.tmp.
In this situation, the time required to determine e max , r A and r B is small as only two bits of e A and e B need be compared.
With reference to FIG. 2, the integers e A and e B are input to a short alignment/shift calculator 11 which generates e max =max(e A , e B ), which is input to a final adder 23 as shown, and also generates two numerical signals r A =max (e B -e A , 0) e max -e A and r B =max (e A -e B 0)=e max -e B that are input, respectively, as select signals to a pair of two input multiplexers 13 and 15. The multiplexer 13 receives input quantities f A and f A /2, e.g., by wiring the appropriate bits of f A to the inputs of multiplexer 13, and, produces a single output,
f.sub.A (if r.sub.A =0),
or
f.sub.A /2 (if r.sub.A =1);
but no time consuming calculations need be performed by multiplexer 13. Similarly, the multiplexer 15 receives the input quantities f B and f B /2 and produces a single output,
f.sub.B (if r.sub.B =0),
or
f.sub.B /2 (if r.sub.B =1).
The numerical signals f A 2 -r .sbsp.A and f B 2 -r .sbsp.B (outputs from the multiplexer 13 and 15, respectively) are now both input to an intermediate adder/subtracter 17 that forms and outputs the sum; and this output is input to priority encoder 19 that forms and outputs the numerical quantity log 2 |f| for any (real, positive) numerical input f. The output S= log 2 |f A 2 -r .sbsp.A +f B 2 -r .sbsp.B | of the priority encoder 19 and the output e max of the calculator 11 are both input to the final adder 23 that forms the sum e' r =e max +S. The output f tmp =f A 2 -r .sbsp.A +f B 2 -r .sbsp.B of the intermediate adder and output S of the priority encoder 19 are both input to a shifter 21 that forms and outputs the numerical quantity f r 2 -S f' tmp . Since S is an integer, multiplication of f tmp by 2 -S is accomplished by merely right shifting f tmp by S places. Note that only one full shift operation is required in this situation, the postnormalization shift, by S bits, since the prealignment shift was eliminated. The prealignment operation was performed simply by comparing the two lowest bits of the exponents to determine the appropriate select signals to a pair of multiplexers which select either the unshifted number or the number right-shifted one bit.
Situation 2: |e A -e B |≧2. Here, division by 2.sup.|e.sbsp.A -e .sbsp.B.sup.| requires an arbitrarily large right shift (by two or more places) for pre-alignment; but postnormalization alignment will require at most a one place shift. To verify this, for the case where e A -e B ≧2, then
|f.sub.A +f.sub.B 2.sup.-(e.sbsp.A.sup.-e.sbsp.B.sup.) |≧|f.sub.A |-|f.sub.B |2.sup.-(e.sbsp.A.sup.-e.sbsp.B.sup.) ≧1-2.sup.1-(e.sbsp.A.sup.-e.sbsp.B.sup.) ≧1-1/2=1/2,
|f.sub.A +f.sub.B 2.sup.-(e.sbsp.A.sup.-e.sbsp.B.sup.) |≦f.sub.A +f.sub.B 2.sup.-(e.sbsp.A.sup.-e.sbsp.B.sup.) ≦2+2.sup.1-(e.sbsp.A.sup.-e.sbsp.B.sup.) ≦5/2.
Thus, the result of addition (or subtraction) of x A and x B can never be so large or so small as to require more than a one place right or left shift to renormalize the sum x A +x B . Formation of the sum (or difference) in this situation may be implemented as follows, as illustrated in FIG. 3.
Set e.sub.max =max (e.sub.A, e.sub.B);
calculate
r.sub.A =max (e.sub.B -e.sub.A, 0)=e.sub.max -e.sub.A
and r.sub.B =max (0, e.sub.A -e.sub.B)=e.sub.max -e.sub.B
f.sub.tmp =f.sub.A 2.sup.-r.sbsp.A +f.sub.B 2.sup.-r.sbsp.B ;
if |f.sub.tmp |≧2, set f.sub.r =1/2 f.sub.tmp and e.sub.r =e.sub.max +1; (1a)
if 1≦|f.sub.tmp |≦2, set f.sub.r =f.sub.tmp and e.sub.r =e.sub.max ; (1b)
if 1/2≦|f.sub.tmp |<1, set f.sub.r =2 f.sub.tmp and e.sub.r =e.sub.max -1; (1c)
The formation of f r , knowing the magnitude of f tmp (1/2≦|f tmp |≦5/2), requires at most a right or left shift of f tmp by one place plus a (simultaneous) addition or subtraction of zero or one from e max for the resultant exponent e r .
These operations are implemented by the apparatus of FIG. 3. The integers e A and e B are input to a (full) alignment calculator 31 which generates e max , r A and r B . The output e max is input to exponent increment means 43 that forms and outputs three signals, e max +1, e max and e max -1, and feeds these three signals to a multiplexer 45.
The short alignment shift calculator 11 of FIG. 2 and the full alignment shift calculator 31 of FIG. 3 may, of course, be combined into a single unit as they receive the same inputs, perform precisely the same operations, and output the same variables; but the invention will form the sum or difference of x A and x B more quickly for |e A -e B |≦1 if a separate short alignment/shift calculator is used since the shift operation in this instance only requires examination of the two lowest order bits of e A and e B .
The signals r A and r B from shift calculator 31 are input, respectively, as control signals to two right shift means (barrel shifters) 33 and 35. The shift means 33 and 35 also receive, respectively, the inputs f A and f B and form the respective outputs f A 2 -r .sbsp.A and f B 2 -r .sbsp.B, by performing right shift of f A and f B by r A and r B places, respectively. The outputs of the right shift means 33 and 35 are input to an intermediate adder/substracter 37 that forms and outputs the sum f tmp =f A 2 -r .sbsp.A +f B 2 -r .sbsp.B. The three signals 1/2 f tmp , f tmp and 2 f tmp are input, e.g., by wiring the appropriate bits to the input, to a multiple input magnitude comparator/multiplexer 41 that determines which of the three inequalities in Equations (1a, b, c) is true. If inequality (1a) is satisfied, the comparator 41 outputs f r =1/2 f.sub. tmp and sends a positive latch signal LS3 to the multiplexer 45, which then outputs e r =e max +1. If inequality (1b) is satisfied, the comparator 41 outputs f r =f tmp and sends a positive latch signal LS4 to the multiplexer 45, which then outputs e r =e max . If inequality (1c) is satisfied, the comparator 41 outputs f r =2 f tmp and sends a positive latch signal LS5 to the multiplexer 45, which then outputs e r =e max -1. If none of the conditions are satisfied (i.e., |f tmp |<1/2), then set f r =f r ' and e r =e' r from FIG. 2.
Thus, the correct output from the FIG. 3 path is determined by testing the magnitude of f tmp in comparator 41 and outputing the appropriate result f r =1/2 f tmp , f tmp or 2f tmp . This process also selects the correct exponent from multiplexer 45. However, all three of the tests 1a, b, c may fail since the initial premise that |e A -e B |≧2 may not have been correct; in this case the correct answer was provided by the circuitry of FIG. 2, i.e., |e A -e B |=0 or 1. Accordingly, the result f' r from FIG. 2 is the fourth input to comparator 41 and is output if the three magnitude tests fail; also the result e' r for FIG. 2 is the fourth input to multiplexer 45 and is output, by applying latch signal LS6, when the final magnitude tests fail. The overall process time has been decreased by performing the simultaneous calculations of FIGS. 2 and 3 as if each case is true and then performing a simple comparison at the end to select the correct answer.
FIGS. 4 and 5 illustrate a second embodiment of the invention, useful for simultaneously generating the sum and difference of two numbers, x A ±x B =f A 2 e .sbsp.A ±f B 2 e .sbsp.B with only a modest increase in apparatus compared with apparatus for the generation of sums of numbers exhibited in FIGS. 2 and 3. In the embodiments illustrated in FIGS. 2 and 3, subtraction was performed essentially the same as addition, using complementary numbers (2's complement form), with the same apparatus. As shown in FIG. 4, for the case where |e A -e B |<2, a short alignment shift calculator 11 is used to determine the control signals r A and r B as was previously described. The signal r A is used as the select signal for a two input multiplexer 13 having inputs f A and 1/2 f A ; thus, the quantity f A is shifted at most one bit. The output from multiplexer 13 is input to adder/subtractor 17. The signal r B is applied as one select signal to four input multiplexer 16 having inputs f B , 1/2 f B , -f B , -1/2 f B where the negative members are in 2's complement form. Force opposite sign means 18, which is an exclusive OR gate, generates an output signal LS9 from two inputs which are the sign bits of f A and f B . The signal LS9 is applied as a second select signal to multiplexer 16 and is used to select the positive or negative output while signal r B is used to select the unshifted or single bit shifted output. The output from multiplexer 16 is also input to adder/subtractor 17. Thus, the output from gate 18 determines if the two numbers are added or subtracted. The multiplexer 16 outputs ±f B 2 -r .sbsp.B, according to sign latch LS9 and signal r B ; and this output together with output f A 2 -r .sbsp.A from the multiplexer 13 are input to an adder/subtractor 17. For the situation |e A -e B |≦1, the remainder of the components of FIG. 4 are the same as in FIG. 2 to produce the resultant e' r .sup.(±) =e max +S.sup.(±) and f' r .sup.(±) =2 -S .spsp.(±) f.sup.(±) tmp for this situation, where
S.sup.(±) = log.sub.2 |f.sub.A 2.sup.-r.sbsp.A ±f.sub.b 2.sup.-r.sbsp.B | and f.sup.(±).sub.tmp =f.sub.A 2.sup.-r.sbsp.A ±f.sub.B 2.sup.-r.sbsp.B.
The independent parallel computation for the case |e A -e B |≧2 is illustrated with reference to FIG. 5, where adder/subtractor 37 of FIG. 3 is replaced by separate adder 36 and subtractor 38 that receive the signals f A 2 -r .sbsp.A and f B 2 -r .sbsp.B from shift means 33 and 35. Adder 36 forms the sum f A 2 -r .sbsp.A +f B 2 -r .sbsp.B =f.sup.(±) tmp and subtractor 38 forms the difference f A 2 -r .sbsp.A -f B 2 -r .sbsp.B =f.sup.(-) tmp . The remainder of the components of FIG. 5 function as in FIG. 3 to produce the resultant e r =e max +{S, 1, 0 or -1} and f r .sup.(±) ={2 -S , 0.5, 1.0 or 2.0}×f.sup.(±) tmp for the situation |e A -e B |≧2 or ≧2 with hardware duplicated on the sum and difference paths. The output from adder 36 is input either unshifted or shifted one bit to the left or right to the inputs of magnitude comparator/multiplexer 41; the result f' r from FIG. 4 is applied to the fourth input. The signal e max for calculator 31 is input to exponent increment means 43 which provides three inputs e max , e max +1, e max -1 to exponent multiplexers 45 and 45A. The output from subtractor 38 is input either unshifted or shifted one bit to the left or right to three inputs of magnitude comparator/ multiplexer 41A with the result f' r from FIG. 4 applied as the fourth input. The comparators 41 and 41A select the proper output as previously described and provide latch signals LS3-6 to multiplexers 45 and 45A to select the proper exponent. Thus, the sum and difference of the two numbers are simultaneously obtained from components 41 and 45 and 41A and 45A.
The apparatus of FIGS. 4 and 5 is useful in generating sums or differences (x A ±x B ) of floating point numbers serially with substantially the same hardware. To perform operations such as the Fast Fourier Transform, simultaneous generation of sums and differences is required. In this instance, the component apparatus of FIGS. 4 and 5 can still be used since sufficient dedicated hardware has been provided for forming the simultaneous sum and difference.
The cicuitry shown in the drawings, described in the specification, used in the reduction to practice, and found to operate successfully in accordance with the invention, are implemented in combination with a 64 bit supercomputer, which provides all the other elements necessary to form an operational digital computer, and which is described in S-1 Project FY 1979 Annual Report, University of California Lawrence Livermore National Laboratory, UCID-18619 (1979), which is incorporated herein by reference. The circuitry can be designed for any number of bits by utilizing the appropriate number of elements. The apparatus for floating point operation is used in combination with a conventional computer which provide all of the necessary functions to operate the floating point apparatus, e.g., forming 2's complements for subtraction operations, or rounding off.
A preferred embodiment of the invention has been constructed using the Fairchild F100K ECL family of logic components. The two-input multiplexers are F100155 Quad Multiplexer/Latch chips while the four-input multiplexers are F100171 Triple 4-Input Multiplexer with Enable chips. The adders are implemented using the F100180 High Speed 6-Bit Adder with the F100179 Carry Lookahead Generator. The priority encoder (count leading zeros) is the F100165 Universal Priority Encoder. The full shifter (barrel shifter) is implemented with the F100158 8-Bit Shift Matrix. These components are described in the Fairchild F100K ECL Data Book, which is herein incorporated by reference.
The preferred embodiments of the invention are implemented using conventional components. Computer structure is described in The Structure of Computers and Computations, Vol. I, by David J. Kuck, J. Wiley and Sons (1978); and Computer Arithmetic Principles, Architecture and Design, by Kai Hwang, J. Wiley and Sons (1979). Floating point arithmetic is described in Kuck, pages 210-216, and Hwang, Chapter 9, which are herein incorporated by reference. A general type of shift means is illustrated by the barrel shifter described in Kuck, pages 231-233. A floating point add unit is illustrated in Hwang, FIG. 9.17 on page 314. The functional means which produces the function S is a priority encoder, e.g., the zero digit check (ZDC) shown in FIG. 9.17. Equivalently, the functional means are implemented using one position counting as described in Kuck, pages 233-234. The preferred embodiments of the invention utilize conventional digital multiplexers, as described in Hwang, pages 33-36; likewise, comparators are conventional digital components, as illustrated in Hwang, pages 45-47 (FIGS. 2.12 and 2.13).
To summarize the basic principles and operations according to the invention an alignment shift calculator receives the integer exponent signals e A and e B , forms the intermediate difference e A -e B , and determines whether e A -e B is positive, negative or zero. If e A -e B >0, the calculator sets e max =max(e A , e B )=e A , r A =max(0, e B -e A )=0 and r B =max(e A -e B , 0)=e A -e B . If e A -e B <0, the calculator sets e max =e B and r A =r B =0. In a short alignment calculator, e A -e B =-1, 0 or +1 so that the integers e max , r A and r B may be quickly determined by testing only the two lowest bits.
A two input multiplexer receives the input signals f A , 1/2 f A and select signal r A and outputs a single signal f 0 =f A (if r A =0) and f 0 =1/2 f A (if r A =1), or f 0 =f A 2 -r .sbsp.A for either choice of r A , thus providing either an unshifted or one-bit shifted output.
Three mutually distinct alternatives are possible:
(1) r A =1, r B =0 and e B -e A =+1;
(2) r A =0, r B =1 and e A -e B =+1;
(3) r A =r B =0 and e A =e B .
If the first alternative is present, x B =2 e .sbsp.B f B >x A =2 e .sbsp.A f A and x A +x B =2 e .sbsp.B {f B +2.sup.(e.sbsp.A -e .sbsp.B.sup.) f A }=2 e .sbsp.B {f B +1/2 f A }; and if it is assumed for definiteness that f B >0 (1≦f B <2), then 0<f B +1/2 f A <3.
(0<|f.sub.B +1/2 f.sub.A)|<3, more generally.)
Similarly, if the second alternative is present and one assumes that f A >0 for definiteness (1≦f A ≦2),
x.sub.A +x.sub.B =2.sup.e.sbsp.A {f.sub.A +1/2 f.sub.B }
0<f.sub.A +1/2 f.sub.B <3.
(0<|f.sub.A +1/2 f.sub.B |<3, more generally.)
If the third alternative is present,
x.sub.A +x.sub.B =2.sup.e.sbsp.A {f.sub.A +f.sub.B },
-4<f.sub.A +f.sub.B <4,
0<|f.sub.A +f.sub.B <4.
In any event, the signal f tmp =2 -r .sbsp.A f A +2 -r .sbsp.B f B is easily formed and satisfies 0<|f tmp |<4.
The priority encoder receives the signal f tmp and produces an output signal S= |log 2 |f tmp | . If |f tmp |=(h 2 , h 1 , h 0 , . . . , h -n+2 ) in binary representation, S is the highest integer p for which h p =1; and -(n-2)≦S≦1. Alternatively, if no h p =1 then f tmp =0 and x A +x B =0. If f tmp ≠0, f r =2 -S f tmp satisfies 1≦f r ≦2. Thus, x A +x B =2 e .sbsp.max f tmp = 2 e .sbsp.max + .sbsp.S f r which displays the floating point decomposition of the sum X A +x B when |e A -e B |≦1.
If |e A -e B |≦2, one again utilizes right shift means and left shift means, an adder, an exponent increment means to produce the integer signals e max +1 and e max -1, given the input integer signal e max and a magnitude comparator.
The magnitude comparator receives the left-shifted signals 2 -S g tmp , 1/2 g tmp , g tmp , and 2/g tmp , where g tmp =f A 2 -r .sbsp.A +f B 2 -r .sbsp.B. If one represents g tmp in binary form as ##EQU1## one easily verifies that |g tmp |<2 if and only if g k =1 for some k≧1,
1≦|g tmp |<2 if and only if g 0 =1 and g k =0 for all k≧1,
|g tmp |<1 if and only if g k =0 for all k≧0.
Thus, the magnitude comparator first determines whether (1) g k =1 for some k≧1, in which case a positive third latch signal is generated and the comparator output signal is f r =1/2 g tmp or (2) g k =0 for all k≧1 and g o =0, in which case a positive fourth latch signal is generated and the comparator output signal is f r =g tmp or (3) g k =0 for all k≧0 but g -1 =1, in which case a positive fifth latch signal is generated and the comparator output signal is f r =2 g tmp or (4) g k =0 for all k≧-1 in which case the result from the case |e A -e B |≦1 is required, i.e., 2 -S g tmp . From the previous development it is known that for
|e.sub.A -e.sub.B |≧2
1/2≦|g.sub.tmp |≦5/2;
and one easily verifies from a consideration of the four cases that 1≦|f r |<2 for all cases. With the definition
e.sub.max +1 if |g.sub.tmp |≧2
e.sub.r =e.sub.max if 1≦|g.sub.tmp |<2
e.sub.max -1 if 1/2≦|g.sub.tmp |<1,
e.sub.max +S if |g.sub.tmp |<1/2
one verifies that
x.sub.A +x.sub.B =2.sup.e.sbsp.max g.sub.tmp =2.sup.e.sbsp.r f.sub.r,
which displays the floating point decomposition of the sum x A +x B when e A -e B ≧2.
The following illustrative examples show how floating point calculations are performed according to the invention. For illustration, where negative numbers are involved, the operation of straight substration is shown (instead of the formation of 2's complements and addition).
EXAMPLE 1
Situation 1 |e a -e B |≦1
Add
1.111 * 2 101110 (decimal 1.875 * 2 46 )
and
-1.000 * 2 101111 (decimal -1.000 * 2 47 )
The mantissas and exponents are
f A =1.111,e A =101110,
f B =-1.000, e B =101111
The exponent difference |e A -e B |=1
Following the FIG. 2 path:
The low order bits of e A are 10 (decimal 2) and the low order bits of e B are 11 (decimal 3). Considering only these bits, then if the exponents are close, i.e., all the higher bits are identical, then e A =e B -1 so r A =-1 and r B =0. The higher bits are not actually checked; the computation is performed as if the condition is true. The prealignment, thus, requires only that f A be shifted once to the right. The addition becomes ##EQU2## By counting leading zeros, S=-4, resulting in
f'.sub.r =2.sup.-S f.sub.tmp =-1.0
e'.sub.r =e.sub.max +S=101111-100=101011 (43)
Thus, the answer is -1.0 * 2 43 .
Following the FIG. 3 path:
Identical values r A and r B are computed (but by a different method), so the addition is as before ##EQU3## The magnitude comparator does not find a one bit in the three test bits, bit (1), bit (0) and bit (-1) (two bits before the point and one bit after) so the FIG. 3 path answers are rejected and the answer from the FIG. 2 path is selected as the correct answer (indicating that the exponent difference was at most one).
EXAMPLE 2
Situation 2 |e A -e B |>1
Add
1.111 * 2 101100 (decimal 1.875 * 2 44 )
and
-1.000 * 2 101111 (decimal -1.000 * 2 47 )
The first path, looking only at the two low order exponent bits, i.e., e A =00 and e B =11, determines that if the exponents are close, then e A =e B -1 (which is obviously incorrect). Proceeding with r A =0 and r B =1 an incorrect answer is produced. The second path determines r A =-2, r B =0. The addition becomes ##EQU4## The magnitude comparator checks the appropriate bits of f tmp and finds that bit (0)=0 while bit (-1)=1 so the correct result is 2 f tmp (left shift by one) and e max -1:
f r =1.0001
e r =101110
Thus, the result is -1.0001×2 101110 =-1.0625×2 46 . Because one of the magnitude comparator tests was satisfied, the correct answer was generated by the FIG. 3 path and the incorrect answer produced by the FIG. 2 path was ignored.
The foregoing description of preferred embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the scope of the invention to the precise form disclosed, and many modifications and variations are possible in light of the above teaching. | Apparatus for decreasing the latency time associated with floating point addition and subtraction in a computer, using a novel bifurcated, pre-normalization/post-normalization approach that distinguishes between differences of floating point exponents. | 6 |
REFERENCE TO RELATED APPLICATIONS
This application is a national stage application under 35 USC 371 of International Application No. PCT/GB2007/002529, filed Jul. 6, 2007, which claims the priority of United Kingdom Application Nos. 0614237.6 and 0618491.5, filed Jul. 18, 2006, and Sep. 20, 2006, respectively, the contents of which prior applications are incorporated herein by reference.
FIELD OF THE INVENTION
The invention relates to a handheld cleaning appliance particularly, but not exclusively, to a handheld vacuum cleaner. More particularly, the invention relates to a handheld cleaning appliance having a cyclonic separator.
BACKGROUND OF THE INVENTION
Handheld vacuum cleaners are well known and have been manufactured and sold by various manufacturers for several years. Typically, a handheld vacuum cleaner comprises a casing which houses a motor and fan unit for drawing air into the cleaner via an inlet, and a separation device such as a filter or bag for separating dirt and dust from the incoming airflow. An example of such a vacuum cleaner is shown in GB1207278.
Handheld vacuum cleaners have more recently been developed to incorporate cyclonic separation systems which are capable of removing larger items of debris from the airflow before removing finer particles using a filter or other barrier means. An example of such a device is sold by Black & Decker under the trade name DUSTBUSTER®. A further example of a handheld vacuum cleaner incorporating a cyclonic separator is shown in GB2035787A.
A disadvantage of known handheld vacuum cleaners which utilise cyclonic separators is that, when only a single cyclone is used followed by a filter or bag, the filter will require maintenance, either by washing or by replacement. Failure to maintain the filter will result in a decrease in performance. It is therefore an object of the invention to provide a handheld cleaning appliance which is capable of sustaining high performance for longer than known handheld vacuum cleaners. It is a further object of the present invention to provide a handheld cleaning appliance which requires less maintenance than existing appliances. A further object of the present invention is to provide a handheld vacuum cleaner which is capable of developing and sustaining higher suction power than is possible with current designs of handheld vacuum cleaner.
SUMMARY OF THE INVENTION
The invention provides a handheld cleaning appliance comprising a dirty air inlet, a clean air outlet and separating apparatus located in an airflow path leading from the air inlet to the air outlet for separating dirt and dust from an airflow, the separating apparatus comprising a cyclonic separator having at least one first cyclone, wherein the cyclonic separator further comprises a plurality of second cyclones arranged in parallel with one another and located downstream of the or each first cyclone.
By providing a cyclonic separator which comprises a plurality of second cyclones in parallel, the handheld cleaning appliance becomes capable of separating fine dirt and dust particles without using barrier means such as filters or bags which need maintenance to ensure that performance remains high over a period of time. It has hitherto been considered difficult to provide a cyclonic separator of this type in a handheld vacuum cleaner because the space occupied by this type of cyclonic separator is considered to be too bulky and heavy to be suitable for a handheld machine. A further advantage of providing a cyclonic separator of this type in a handheld vacuum cleaner is that the cleaner is then capable of sustaining high suction power because there is no barrier-type filter means to cause a reduction in suction power, and hence pick-up capability, over time.
Preferably, the handheld cleaning appliance includes a handle and the cyclonic separator lies between the handle and the dirty air inlet. This provides an arrangement which is well balanced for a user of this type of cleaning appliance.
It is preferred that the cyclonic separator lies substantially parallel to the handle, and it is further preferred that the cyclonic separator lies in a generally upright configuration. These features have been found to be beneficial for manipulation and for convenient storage and emptying of the dirt and dust collected in the cyclonic separator.
In a preferred embodiment of the invention, a single first cyclone is provided and the second cyclones are spaced around an axis of the first cyclone. This provides a compact arrangement which is balanced for ease of manipulation. It is more preferable that each of the second cyclones has an end which projects into the first cyclone so as to provide a convenient balance of dirt collecting capacity and overall volume of the cyclonic separator.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the invention will now be described with reference to the accompanying drawings, in which:
FIG. 1 shows a handheld cleaning appliance according to the invention;
FIG. 2 is a side view of the appliance of FIG. 1 ; and
FIG. 3 is a longitudinal cross section through the cyclonic separating apparatus forming part of the appliance of FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1 and 2 show a handheld vacuum cleaner 10 . The handheld vacuum cleaner 10 has a main body 12 which houses a motor and fan unit (not shown). The main body 12 also includes a power source 14 such as a battery. A handle 16 is provided on the main body 12 for manipulating the handheld vacuum cleaner 10 in use. A cyclonic separator 100 is attached to the main body 12 . A dirty air inlet 18 extends from a portion of the cyclonic separator 100 remote from the main body 12 . A brush tool 22 is slidably mounted on the distal end of the dirty air inlet 18 . A set of exhaust vents 24 are provided on the main body 12 for exhausting air from the handheld vacuum cleaner 10 .
The cyclonic separator 100 is located between the main body 12 and the dirty air inlet 18 . Consequently, the cyclonic separator 100 is located between the handle 16 and the dirty air inlet 18 . The cyclonic separator 100 has a longitudinal axis 26 which extends in a generally upright direction so that the axis 26 , and therefore the cyclonic separator 100 , lies substantially parallel to the direction in which the handle 16 extends.
The orientation of the handle 16 is such that, when the user grips the handle 16 , the user's hand forms a fist in a manner similar to that adopted when gripping a saw. This ensures that the user's wrist is not strained more than necessary when manipulating the handheld vacuum cleaner 10 for cleaning purposes. The cyclonic separator 100 is positioned close to the handle 16 which also reduces the moment applied to the user's wrist when the handheld vacuum cleaner 10 is in use. The handle 16 carries an on/off switch 20 in the form of a trigger for turning the vacuum cleaner motor on and off.
The cyclonic separating apparatus 100 forming part of the handheld vacuum cleaner 10 is shown in more detail in FIG. 3 . The cyclonic separating apparatus 100 comprises a first cyclone 102 which has a longitudinal axis X-X and a wall 104 . An inlet 110 is formed in the upper portion of the wall 104 . The inlet 110 is in communication with the dirty air inlet 18 and forms a communication path between the dirty air inlet 18 and the interior of the first cyclone 102 . The air inlet 110 is arranged tangentially to the first cyclone 102 so that the incoming air is forced to follow a helical path around the interior of the first cyclone 102 .
A base 116 closes one end of the first cyclone 102 . The base 116 is pivotably mounted on the lower end of the first cyclone wall 104 by means of a hinge 118 . The base 116 is retained in a closed position (as shown the figures) by means of a catch 120 .
A shroud 121 is located inwardly of the wall 104 of the first cyclone 102 . The shroud 121 comprises a cylindrical wall 122 having a plurality of through-holes 123 . The shroud 121 surrounds an outlet 124 from the first cyclone 102 . The outlet 124 provides a communication path between the first cyclone 102 and a second cyclone assembly 126 . A lip 128 is provided at the base of the shroud 121 . The lip 128 has a plurality of through-holes 129 which are designed to allow air to pass through but to capture dirt and dust.
The second cyclone assembly 126 comprises a plurality of second cyclones 130 arranged in parallel with one another. In this embodiment, six second cyclones 130 are provided. The second cyclones 130 are arranged around the axis X-X of the first cyclone 102 . The arrangement of the second cyclones 130 is such that the second cyclones are spaced equi-angularly around the axis X-X. Each second cyclone 130 has a tangentially-arranged air inlet 132 and an air outlet 134 . Each air inlet 132 and air outlet 134 is located at a first end of the respective second cyclone 130 . A cone opening 136 is located at a second end of each second cyclone 130 . The plane of the cone opening 136 of each second cyclone 130 is inclined with respect to a longitudinal axis (not shown) of the respective further cyclone 130 . The cone opening 136 of each of the second cyclones 130 is in communication with a passageway 138 defined by a wall 140 located inwardly of the shroud 121 .
The second end of each second cyclone 130 projects into the interior of the first cyclone 102 . However, the first end of each second cyclone 130 lies outside the envelope of the first cyclone 102 . In the orientation shown, it is the lower end of each second cyclone 130 which projects into the upper end of the first cyclone 102 . The inlet 110 is also arranged at the upper end of the first cyclone 102 so that the inlet 110 is located in the region of the cyclonic separator 100 in which the first and second cyclones 102 , 130 overlap. Because the first ends of the second cyclones 130 lie outside the envelope of the first cyclone, this region of the cyclone separator 100 lies intermediate the upper end of the cyclone separator 100 and the lower end of the cyclone separator 100 . Connecting the dirty air inlet 18 to the cyclone separator 100 at an intermediate portion thereof is beneficial for the manipulation of the handheld vacuum cleaner 10 and avoids the lower extremities of the appliance being accidentally knocked on surfaces away from the area being cleaned.
A collector 142 is located at the lower end of the passageway 138 . The collector 142 comprises a frustoconical first portion 144 and a cylindrical second portion 146 . The interior of the collector 142 is delimited by the base 116 and the sides of the first and second portions 144 , 146 of the collector 142 .
Each of the air outlets 134 of the second cyclones 130 is in communication with a duct 150 . The duct 150 provides an airflow path from the cyclonic separating apparatus 100 into other parts of the handheld vacuum cleaner 10 . Located at the downstream end of the duct 150 is a pre-motor filter 152 . The pre-motor filter 152 comprises a porous material such as foam and can also include a fine filter material. The pre-motor filter 152 is designed to prevent any fine dust particles from entering the motor and causing damage thereto.
In use, when the on/off switch 20 is depressed, the motor and fan unit draws a flow of dirt-laden air into the dirty air inlet 18 and then into the cyclonic separator 100 . Dirt-laden air enters the cyclonic separator 100 through the inlet 110 . Due to the tangential arrangement of the inlet 110 , the airflow is forced to follow a helical path around the interior of the wall 104 . Larger dirt and dust particles are separated by cyclonic motion around the wall 104 . These particles are then collected at the base 116 of the first cyclone 102 .
The partially-cleaned airflow then flows back up the interior of the first cyclone 102 and exits the first cyclone 102 via the through-holes in the shroud 121 . Once the airflow has passed through the shroud 121 , it enters the outlet 124 and from there is divided between the tangential inlets 132 of each of the second cyclones 130 . Each of the second cyclones 130 has a diameter which is smaller than that of the first cyclone 102 . Therefore, the second cyclones 130 are able to separate smaller particles of dirt and dust from the partially-cleaned airflow than the first cyclone 102 . Separated dirt and dust exits the second cyclones 130 via the cone openings 136 . Thereafter, the separated dirt and dust passes down the passageway 138 and into the collector 142 . The separated dirt and dust eventually settles at the bottom of the collector 142 on the base 116 .
Cleaned air then flows back up the second cyclones 130 , exits the second cyclones 130 through the air outlets 134 and enters the duct 150 . The cleaned air then passes from the duct 150 sequentially through the pre-motor filter 152 , the motor and fan unit, and a post-motor filter before being exhausted from the vacuum cleaner 10 through the air vents 24 .
The first cyclone 102 and the collector 142 can be emptied simultaneously by releasing the catch 120 to allow the base 116 to pivot about the hinge 118 so that the separated dirt and dust can fall away from the cyclonic separator 100 . This allows efficient and reliable emptying of the dirt and dust from the cyclonic separator 100 at periodic intervals convenient to the user.
The invention is not limited to the precise details of the embodiment described above. For example, the number of second cyclones can be varied, as can the detail of their design, such as their cone angle, axis inclination and cone opening inclination. The collected dirt and dust can be released in other ways, such as by complete removal of the lower portion of the first cyclone 102 , and the location of the on/off switch may be varied. | A handheld cleaning appliance includes a dirty air inlet, a clean air outlet and separating apparatus for separating dirt and dust from an airflow in an airflow path leading from the air inlet to the air outlet. The separating apparatus includes a cyclonic separator having at least one first cyclone and a plurality of second cyclones arranged in parallel with one another and located downstream of the first cyclone. By providing a cyclonic separator having a plurality of second cyclones in parallel, the handheld cleaning appliance is capable of separating fine dirt and dust particles without using barriers such as filters or bags which need maintenance to ensure that performance remains high over a period of time. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to silicone emulsions and more specifically to a silicone emulsion composition that is useful as a mold release coating in aluminum die casting.
2. Description of the Prior Art
Silicone emulsion compositions prepared by dispersing organopolysiloxanes uniformly in water with the aid of an emulsifier are widely used as fiber processing agents, mold releasing agents, paint additives, and cosmetic feed materials. Examples of this type of silicone emulsion composition include a silicone emulsion composition made from an aqueous emulsion of dimethylpolysiloxane and polyoxyethylene alkyl phenyl ether sulfuric acid sodium (see Japanese Kokoku Patent No. Sho 53[1978]-13501) and emulsions made from cyclic methylpolysiloxane, emulsifier, and water (see, for instance, Japanese Kokai Patent Application No. Sho 56[1981]-95952.)
Conventional silicone emulsion compositions such as those described above suffer from the drawback that they have a poor mechanical stability. That is to say that under mechanical shear, the emulsion form is easily damaged. For example, when these silicone emulsion compositions are used as a mold release in an aluminum die-casting operation, the silicone emulsion composition is generally diluted several tens of times with water. The diluted solution is fed from a reservoir by a gear pump and sprayed onto the surface of a mold. The water in the emulsion is evaporated therefrom to form a uniform oil film of organopolysiloxane on the surface of the mold. Excess amounts of the diluted solution are recovered for recycling, being fed back by a gear pump. In this repeated liquid feed method, emulsion damage takes place, and it is thereafter impossible to uniformly coat the mold.
The oil film produced by the aforementioned conventional silicone emulsion compositions has an additional drawback in that has a poor paintability. Consequently, when these silicone emulsion compositions are used as a mold releasing agent, the oil film adheres to the surface of the die-cast part and makes painting or marking the part very difficult.
Finally, the oil film produced by the prior art silicone emulsion compositions has a low strength and hence, it has poor lubricity under extreme-pressure. Consequently, when these silicone emulsion compositions are used as a mold releasing agent in aluminum die-cast molding, cracks often form in the oil film produced therefrom. Such cracks cause the aluminum melt to misrun, which produces surface defects in the die cast part.
BRIEF SUMMARY OF THE INVENTION
In accordance with the present invention there is provided a silicone emulsion composition useful as a mold coating in aluminum die casting operations. The silicone emulsion composition of the invention has high mechanical stability and, upon removal of water therefrom, forms an oil film with excellent paintability and extreme-pressure lubricating properties.
The silicone emulsion composition of the invention comprises: (A) an aqueous emulsion of an organopolysiloxane; and (B) an alkyl diphenyl ether disulfonate salt. The alkyl diphenyl ether disulfonate salt (B) is present in the composition in the range of 0.2-10 parts by weight, with respect to 100 parts by weight of the organopolysiloxane of component (A). The oraganopolysiloxane (A) has the general formula: ##STR1## wherein:
R 1 is selected from the group consisting of monovalent hydrocarbon radicals having one to seven carbon atoms and combinations thereof;
R 2 is selected from the group consisting of
a monovalent hydrocarbon radical having eight or more carbon atoms,
a monovalent hydrocarbon radical of the general formula --R 3 COOR 4 wherein R 3 is a divalent hydrocarbon radical and R 4 is hydrogen or monovalent hydrocarbon radical,
a monovalent hydrocarbon radical of the general formula --R 3 OOCR 5 wherein R 3 is a divalent hydrocarbon radical and R 5 is a monovalent hydrocarbon radical and
combinations thereof;
A is a radical selected from the group consisting of
hydroxyl radicals,
monovalent hydrocarbon radicals,
radicals of the general formula --R 3 COOR 4 wherein R 3 and R 4 are as described above,
radicals of the general formula --R 3 OOCR 5 wherein R 3 and R 5 are as described above, and
combinations thereof; and
x is an integer between 1 and 50, inclusive;
y is an integer between 10 and 450, inclusive; and
x<y.
It is therefore an object of the present invention to provide a novel silicone emulsion composition that is useful as a mold coating in aluminum die casting.
It is another object of the present invention to provide a novel silicone emulsion composition which has high stability when diluted with water and subjected to mechanical shear.
Still another object of the invention is to provide a novel silicone emulsion composition which, when applied to a preheated mold so that the water is driven from the emulsion, forms a uniform oil film thereon, which film has good paintability and extreme-pressure lubricity.
These and other objects and features of the present invention will become apparent to those skilled in the art from the following detailed description of the invention and examples thereof.
DETAILED DESCRIPTION OF THE INVENTION
In accordance with the invention there is provided a novel silicone emulsion composition which is useful as a mold coating in aluminum die casting. The silicone emulsion composition of the invention comprises: (A) an aqueous emulsion of an organopolysiloxane; and (B) an alkyl diphenyl ether disufonate salt.
The aqueous emulsion of component (A) is prepared by uniformly dispersing the organopolysiloxane of the following general formula in water, together with an emulsifier: ##STR2##
In the aforementioned formula, R 1 is selected from the group consisting of monovalent hydrocarbon radicals having one to seven carbon atoms and combinations thereof. Examples include methyl radical, ethyl radical, propyl radical, butyl radical, pentyl radical, hexyl radical, heptyl radical, and other alkyl radicals; phenyl radical, tolyl radical, and other aryl radicals; cyclopentyl radical, methylcyclopentyl radical, cyclohexyl radical, cycloheptyl radical, and other cycloalkyl radicals, etc. When the silicone emulsion composition of this invention is used as the mold releasing agent, it is preferred that at least 50% of R 1 radicals in the organopolysiloxane be methyl radicals.
R 2 is a monovalent radical selected from the group consisting of monovalent hydrocarbon radicals having eight or more carbon atoms; radicals represented by formula --R 3 COOR 4 wherein R 3 represents a divalent hydrocarbon radical and R 4 represents a hydrogen atom or monovalent hydrocarbon radical; radicals represented by formula --R 3 OOCR 5 wherein R 3 represents a divalent hydrocarbon radical and R 5 represents a monovalent hydrocarbon radical; and combinations thereof. Examples of monovalent hydrocarbon radicals having 8 or more carbon atoms include octyl radical, nonyl radical, decyl radical, undecyl radical, dodecyl radical, and other alkyl radicals; ethyl phenyl radical, propyl phenyl radical, butyl phenyl radical, and other aryl radicals; phenyl radical, phenyl propyl radical, phenyl butyl radical, and other aralkyl radicals.
In the radicals represented by formula --R 3 COOR 4 , R 3 represents divalent hydrocarbon radical, such as an ethylene radical, propylene radical, methylethylene radical, butylene radical, pentylene radical, or other divalent hydrocarbon radical, etc.; R 4 represents a hydrogen atom or monovalent hydrocarbon radical, such as a methyl radical, ethyl radical, propyl radical, and other alkyl radicals; phenyl radical, tolyl radical, xylyl radical, and other aryl group, etc.
Consequently, examples of the radicals represented by formula --R 3 COOR 4 include a carboxymethyl radical, carboxyethyl radical, carboxypropyl radical, and other carboxyalkyl radicals; methoxycarbonylmethyl radical, methoxycarbonylethyl radical, methoxycarbonylpropyl radical, ethoxycarbonylethyl radical, propoxycarbonylethyl radical, butoxycarbonylpropyl radical, and other alkoxycarbonylalkyl radicals, etc.
In the radicals represented by --R 3 OOCR 5 , R 5 represents a monovalent hydrocarbon radical, such as a methyl radical, ethyl radical, propyl radical, and other alkyl radicals; phenyl radical, tolyl radical, xylyl radical, and other aryl radicals, etc.
Consequently, examples of the radicals represented by --R 3 OOCR 5 include an acetyloxymethyl radical, acetyloxyethyl radical, acetyloxypropyl radical, propionyloxyethyl radical, propionyloxypropyl radical, butylyloxypropyl radical, and other acyloxyalkyl radicals, etc.
In the aforementioned formula, A represents a radical selected from the group consisting of hydroxyl radicals; monovalent hydrocarbon radicals; radicals represented by formula --R 3 COOR 4 wherein R 3 represents divalent a hydrocarbon radical and R 4 represents a hydrogen atom or monovalent hydrocarbon radical; radicals represented by formula --R 3 OOCR 5 wherein R 3 represents a divalent hydrocarbon radical and R 5 represents a monovalent hydrocarbon radical; and combinations thereof.
Examples of the monovalent hydrocarbon radicals are the same as above.
Examples of the radicals represented by formula --R 3 COOR 4 are the same as listed above.
Examples of the radicals represented by formula --R 3 OOCR 5 are the same as listed above.
In the aforementioned formula, x represents an integer in the range of 1-50; y represents an integer in the range of 10-450, with x<y. This is because if x becomes larger than 50, the paintability property of the oil film formed from the composition of the invention is degraded. If y is smaller than 10, the paintability is also degraded.
On the other hand, if y is larger than 450, the mechanical stability of the composition of this invention is degraded.
If (x+y) becomes larger than 500, the viscosity of the organopolysiloxane is increased, making it difficult to perform emulsification.
In order to improve the paintability of the oil film produced from the emulsion of the inventions, it is necessary to have x<y. It is preferred that R 2 represent the radical represented by the formula --R 3 COOR 4 or the radical represented by formula --R 3 OOCR 5 . R 3 represent an alkylene radical, R 4 represent a hydrogen atom or alkyl radical, R 5 represent an alkyl radical, and the carbon atom numbers in R 3 , R 3 +R 4 , R 3 +R 5 are larger than 10 for the organopolysiloxane used. In this case, the organopolysiloxane is oriented on the surface of the mold, and the mold releasing property is particularly good.
There is no special limitation the manufacturing method of the aforementioned organopolysiloxane. For example, the following method may be used: in the presence of chloroplatinic acid or other catalyst for the hydrosilylation reaction, methylhydrogenpolysiloxane or a dimethylsiloxanemethylhydrogensiloxane copolymer is added with the α-olefin or α-methylstyrene represented by the following formulas:
CH 2 ═CH(CH 2 ) 5 CH 3 ,
CH 2 ═CH(CH 2 ) 10 CH 3 ,
CH 2 ═CH(CH 2 ) 12 CH 3 ,
or unsaturated fatty acid represented by the following formulas
CH 2 ═CHCOOH,
CH 2 ═CH(CH 2 ) 5 COOH,
CH 2 ═CH(CH 2 ) 8 COOH,
CH 2 ═CH(CH 2 ) 12 COOH,
or the ester compound of unsaturated fatty acid represented by the following formulas:
CH 2 ═CHCOOCH 3 ,
CH 2 ═CHCOOC 3 H 7 ,
CH 2 ═C(CH 3 ) 8 COOC 3 H 7 ,
CH 2 ═CH(CH 2 ) 8 COOC 6 H 5 ,
CH 2 ═CH(CH 2 ) 8 COOC 2 H 5 ,
CH 2 ═CH(CH 2 ) 8 COOC 3 H 7 ,
CH 2 ═CH(CH 2 ) 12 COOC 3 H 7 ,
or the ester compound of the unsaturated aliphatic alcohol represented by the formulas:
CH 2 ═CHCH 2 OOCCH 3 ,
CH 2 ═CHCH 2 OOCC 6 H 5 ,
CH 2 ═CHCH 2 OOCC 11 H 23 ,
CH 2 ═CH(CH 2 ) 5 OOCC 11 H 23 .
The aqueous emulsion of component (A) can be manufactured by dispersing the aforementioned organopolysiloxane uniformly in water with the aid of an emulsifier. According to this invention, there is no special limitation on the type of the emulsion used. Examples of the emulsifiers that may be used include nonionic surfactants, anionic surfactants, etc. Examples of the nonionic surfactants include polyoxyalkylene alkyl ethers; polyoxyalkylene alkyl phenyl ethers; polyoxyalkylene alkylesters; polyoxyalkylene sorbitan alkyl esters; sorbitan alkyl esters; polyethylene glycol; polypropylene glycol, etc. Examples of anionic surfactants include octylbenzene sulfonic acid, dodecylbenzene sulfonic acid, and other alkylbenzene sulfonic acids; higher alcohol sulfuric ester; polyoxyethylene alkyl ether sulfuric ester; sodium salt, potassium salt, lithium salt, or ammonium salt, etc. of alkylnaphthyl sulfonic acid; etc. It is also possible to use the alkyl diphenyl ether disulfonate salt of component (B).
The alkyl diphenyl ether disulfonate salt of component (B) is a component for making the silicone emulsion composition of the invention acquire mechanical stability and extreme-pressure lubricating properties. There is no special limitation on the type of the alkyl diphenyl ether disulfonate salt of component (B). For example, the compound represented by the following formula may be used: ##STR3##
In this formula, R 6 represents a C 3-20 alkyl radical, such as a propyl radical, butyl radical, octyl radical, nonyl radical, decyl radical, dodecyl radical, and other alkyl radicals, or preferably a C 8-12 alkyl radical. M represents a cation, such as a sodium ion, potassium ion, lithium ion, ammonium ion, etc., or preferably a sodium or potassium ion. Examples of component (B) include butyl diphenyl ether disulfonic acid sodium, nonyl diphenyl ether disulfonic acid sodium, dodecyl diphenyl ether disulfonic acid sodium, dodecyl diphenyl ether disulfonic acid potassium, butyl diphenyl ether disulfonic acid lithium, nonyl diphenyl ether disulfonic acid ammonium, dodecyl diphenyl ether disulfonic acid ammonium and dodecyl diphenyl ether disulfonic acid lithium, etc.
According to this invention, with respect to 100 parts by weight of the organopolysiloxane in component (A), the amount of component (B) should be in the range of 0.2-10 parts by weight, or preferably in the range of 1-6 parts by weight. This is because, if the amount of component (B) is less than 0.2 part by weight with respect to 100 parts by weight of the organopolysiloxane in component (A), the silicone emulsion composition has insufficient mechanical stability and extreme-pressure lubricating properties. On the other hand, if the amount is over 10 parts by weight, the silicone emulsion composition has poor storage stability, the relative concentration of organopolysiloxane is decreased, and the mold releasing properties of the oil film obtained from the emulsion of the invention is degraded.
While the silicone emulsion composition of this invention has components (A) and (B) as the main components, it also may contain additives. Such additives may include preservatives, fungicides, rust inhibitors, coloring agents, mineral oils, higher fatty acids, thickeners, aluminum powder, graphite, etc.
There is no special limitation on the method of manufacturing the silicone emulsion composition of the present invention. The conventional silicone emulsion composition manufacturing method may be used. More specifically, the aforementioned components may be emulsified by using homomixer, colloid mill, line mixer, homogenizer, and other emulsifying apparatus.
The silicone emulsion composition of this invention has excellent mechanical stability and the oil film produced therefrom has extreme-pressure lubricating properties. For example, the silicon emulsion composition may be used in making a mold releasing agent in an aluminum die-casting operation where the emulsion is subjected to repeated mechanical shear force and an oil film having good extreme-pressure lubricating properties is required.
APPLICATION EXAMPLES
The present invention will be explained with reference to the following application examples. In these application examples, "parts" refers to parts by weight, and % represents wt %. The viscosity refers to centistokes measured at 25° C. The structural formulas and viscosity values of the types of organopolysiloxane used in the application examples are listed below:
(I) With viscosity of 1130 cs ##STR4##
(II) With viscosity of 980 cs ##STR5##
(III) With viscosity of 1630 cs ##STR6##
(IV) With viscosity of 1040 cs ##STR7##
(V) With viscosity of 1320 cs ##STR8##
In addition, the types of the alkyl diphenyl ether disulfonate salts used in the application examples are as follows:
(a) Nonyl diphenyl ether disulfonic acid sodium,
(b) Dodecyl diphenyl ether disulfonic acid sodium, and
(c) Dodecyl diphenyl ether disulfonic acid potassium.
In the application examples and comparative examples, the silicone emulsion compositions were assessed using the following methods:
Paintability: The silicone emulsion composition was diluted 50 times by water. The diluted solution was sprayed on paper by means of a simple spray gun, followed by drying at room temperature. Then, equidistant lines were drawn by means of a rule using a felt pen for drawing oily fat lines. The quality of the lines was then evaluated.
o: The lines were not coarse at all, and the ink was attached uniformly.
Δ: The lines were partially coarse, and the ink attachment was a little uneven.
X: The lines were significantly coarse.
Mold releasing property: The silicone emulsion composition was diluted to a concentration of organopolysiloxane of 2% was sprayed on a mold, which mold had inner dimensions of 5 cm×5 cm and a depth of 5 mm, and which mold had many grooves on its bottom, followed by preheating at about 350° C. Molten aluminum heated to about 750° C. in an electric oven was poured into this mold, followed by cooling. Then, the aluminum piece was peeled off from the mold, and the peeling performance was assessed.
⊚: The mold releasing property was excellent.
o: The mold releasing property was good.
Δ: The mold releasing property was a little poor.
X: The mold releasing agent was poor.
Storage stability: 180 mL of the silicone emulsion composition was loaded into a 200 mL glass bottle, followed by setting undisturbed at a room temperature of 25° C. for 3 months to study the storage stability.
Mechanical stability: The silicone emulsion composition was diluted with water to a concentration of organopolysiloxane of 0.5%. Then, 600 g of the diluted solution was loaded into a 1000 mL beaker, followed by stirring at 10000 rpm for 1 h using a homomixer. Then, the sample was left undisturbed for 3 h, and inspected for the attachment of the oil-like substance on the wall of the beaker, the presence/absence of oil-like substance on the surface of the solution, and the presence/absence of cream-like substance.
o: No oil-like substance on the surface of the solution, and no cream-like substance were observed.
○: A little oil-like substance on the surface of the solution, and a little cream-like substance were observed.
Δ: Oil-like substance floating on a portion of the surface of the solution, and cream-like substance on the entire surface of the solution were observed.
X: Oil-like substance floating on entire surface of the solution, and a large amount of cream-like substance were observed.
Extreme-pressure lubricating properties: According to the Lubricating Oil Load Test Method defined in JIS-K-2519, the seize load (kg) was evaluated. The measurement conditions and the measurement equipment specifications are as follows.
Form and name: 4-ball type friction tester (produced by Kobe Steel Equipment Mfg. Co., Ltd.)
Test steel balls: 3/4" steel ball bearings (basic diameter of 19.05 mm)
Higher rank: JIS-B-1501.
Load on the test steel balls: Max. 1000 kg
Rotating speed of spindle: 750 rpm
APPLICATION EXAMPLE 1
50 parts of organopolysiloxane (I) and 4 parts of polyoxyethylene (6 mol) lauryl ether were dispersed uniformly by means of a stirrer. Then, 4 parts of water were added, followed by stirring and emulsification using a colloid type emulsifier. Then, 39 parts of water were added to form the aqueous emulsion of organopolysiloxane (I). Then, 1.5 parts of alkyl diphenyl ether disulfonate salt (a)-(c) were added into the aforementioned aqueous emulsion, forming three types of silicone emulsion compositions, respectively. For the obtained samples of silicone emulsion compositions, the paintability, mold releasing property, storage stability and extreme-pressure lubricating property were studied. The results are listed in Table I.
TABLE I______________________________________Item Measured This Invention______________________________________Alkyl Diphenyl A B CEther DisulfonateSaltPaintability ◯ ◯ ◯Mold Releasing ⊚ ⊚ ⊚PropertyStorage Stability Good Good GoodMechanical Stability ⊚ ⊚ ⊚Extreme-Pressure 100 110 110LubricatingPropertyGeneral Assessment Appropriate Appropriate Appropriate______________________________________
COMPARATIVE EXAMPLE 1
Silicone emulsion compositions were prepared in the same way as in Application Example 1 except that the alkyl diphenyl ether disulfonate salt added in Application Example 1 was not added, while water was added instead, and the following listed emulsifiers were added, respectively. The properties of these compositions were measured in the same way as in Application Example 1. The results are listed in Table II.
(d) Sodium laurylsulfate
(e) Polyoxyethylene (4 mol) lauryl ether sulfuric acid sodium
(f) Polyoxyethylene (4 mol) nonyl phenyl ether sulfuric acid sodium
(g) Dodecylbenzene sulfonic acid sodium
TABLE II______________________________________Item Measured Comparative Examples______________________________________Emulsifier Not d e f g AddedPaintability ◯ ◯ ◯ ◯ ◯Mold Releasing Δ˜◯ Δ˜◯ Δ˜◯ Δ˜◯ Δ˜◯PropertyStorage Stability Good Good Good Good GoodMechanical Δ˜◯ ◯˜⊚ ◯˜⊚ ⊚ ⊚StabilityExtreme-Pressure 70 70 80 70 80LubricatingPropertyGeneral Assessment Insuf- Insuf- Insuf- Insuf- Insuf- ficient ficent ficent ficent ficent______________________________________
APPLICATION EXAMPLE 2
4 parts of polyoxyethylene (6 mol) lauryl ether and 0.5 part of dodecylbenzene sulfonic acid sodium were added into 50 parts of organopolysiloxane (II), (III), and (IV), followed by stirring to a uniform state using a stirrer. Then, 5 parts of water were added, followed by stirring and emulsification using a colloid mill type emulsifier. Then, 38.5 parts of water were added to form an aqueous emulsion. 2 parts of dodecyl diphenyl ether sulfonic acid sodium were added into the obtained aqueous emulsion to form the silicone emulsion composition. The properties of the composition were measured in the same way as in Application Example 1, with results listed in Table III.
TABLE III______________________________________Item Measured This Invention______________________________________Organopolysiloxane II III IVEmulsifier b b bPaintability ◯ ◯ ◯Mold Releasing ⊚ ⊚ ⊚PropertyStorage Stability Good Good GoodMechanical Stability ⊚ ⊚ ⊚Extreme-Pressure 110 120 120LubricatingPropertyGeneral Assessment Appropriate Appropriate Appropriate______________________________________
COMPARATIVE EXAMPLE 2
Four types of silicone emulsion compositions were prepared in the same way as in Application Example 2 except that the following listed emulsifiers were used in place of the dodecyl diphenyl ether disulfonic acid sodium used in Application Example 2. The characteristics of these silicone emulsion compositions were measured in the same way as in Application Example 1. The results are listed in Table IV and Table V.
(h) polyoxyethylene (6 mol) lauryl ether
(i) polyoxyethylene (9.5 mol) nonyl phenyl ether
(j) polyoxyethylene (10 mol) monostearate
(k) decaglyceryl monoleate
TABLE IV______________________________________ItemMeasured Comparative Examples______________________________________Organopoly- II III V II III VsiloxaneEmulsifier h h h i i iPaintability ◯ ◯ ◯ ◯ ◯ ◯Mold Δ Δ˜◯ Δ˜◯ Δ˜◯ Δ˜◯ Δ˜◯ReleasingPropertyStorage Good Good Good Good Good GoodStabilityMechanical Δ˜◯ ◯ Δ˜◯ ◯ Δ˜◯ ◯StabilityExtreme- 70 80 70 60 70 70PressureLubricatingPropertyGeneral Insuf- Insuf- Insuf- Insuf- Insuf- Insuf-Assessment ficient ficent ficent ficent ficent ficent______________________________________
TABLE V______________________________________ItemMeasured Comparative Examples______________________________________Organopoly- II III V II III VsiloxaneEmulsifier j j j k k kPaintability ◯ ◯ ◯ ◯ ◯ ◯Mold Δ˜◯ Δ Δ˜◯ Δ Δ˜◯ Δ˜◯ReleasingPropertyStorage Good Good Good Good Good GoodStabilityMechanical ◯ ◯ Δ˜◯ Δ˜◯ Δ˜◯ Δ˜◯StabilityExtreme- 70 80 80 70 80 70PressureLubricatingPropertyGeneral Insuf- Insuf- Insuf- Insuf- Insuf- Insuf-Assessment ficient ficent ficent ficent ficent ficent______________________________________
APPLICATION EXAMPLE 3
Five types of silicone emulsion compositions were prepared in the same way as in Application Example 1 except that instead of the organopolysiloxane (I) used in Application Example 1, organopolysiloxane (IV) was used, and that with respect to 100 parts by weight of organopolysiloxane (IV), 0.1 part, 1 part, 3 parts, 6 parts, and 15 parts of dodecyl diphenyl ether sulfonic acid sodium were added, respectively. In addition, a type of silicone emulsion composition was prepared in the same way as above but without adding dodecyldiphenyl ether sulfonic acid sodium. The characteristics of these silicone emulsion compositions were measured in the same way as in Application Example 1, with results listed in Table VI. It can be seen from these results that the silicone emulsion composition of this invention has excellent mechanical stability, extreme-pressure lubricating properties and paintability. On the other hand, the silicone emulsion composition prepared by adding 0.1 part of dodecyl diphenyl ether disulfonate sodium has insufficient mechanical stability and extreme-pressure lubricating properties. For the silicone emulsion composition prepared by adding 15 parts of dodecyl diphenyl ether disulfonate sodium, the storage stability and the mold releasing property were poor.
TABLE VI______________________________________ItemMeasured Application Example Comparative Example______________________________________Dodecyl 1 Part 3 Parts 6 Parts Not 0.1 15Diphenyl Added Part PartsEtherDisulfonateSodiumPaintability ◯ ◯ ◯ ◯ ◯ ◯Mold ⊚ ⊚ ⊚ Δ˜◯ Δ˜◯ ΔReleasingPropertyStorage Good Good Good Good Good PoorStabilityMechanical ⊚ ⊚ ⊚ Δ Δ˜◯ ⊚StabilityExtreme- 110 120 130 70 70 130PressureLubricatingPropertyGeneral Ap- Ap- Ap- Insuf- Insuf- Insuf-Assessment pro- pro- pro- ficent ficent ficent priate priate priate______________________________________ | There is disclosed a novel silicone emulsion useful as a mold coating in aluminum die casting operations. The silicone emulsion of the invention comprises an aqueous dispersion of an organopolysiloxane of a particular general formula in combination with an alkyl diphenyl ether disulfate salt. The novel silicone emulsion of the invention exhibits stability even when diluted tens of times and subjected to mechanical shear. When applied to a heated mold surface, water is driven from the silicone emulsion and there is formed a oil film. The oil film allows for easy release of the cast part. Furthermore, the film exhibits good paintability and lubricity under extreme pressure. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit of the filing date of U.S. Provisional Application No. 60/194,081 filed Apr. 3, 2000, the teachings of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to joints formed in metal parts and to structures formed using the same.
BACKGROUND OF THE INVENTION
[0003] A commonly used method of providing high strength and lightweight characteristics is to construct a structure using a cellular web extending between respective plates. The web may be typically honeycomb shaped with each honeycomb cell having a hexagonal shape. The honeycomb shapes may be formed of corrugated metal strips laterally displaced from one another and joined to have the appearance of natural honeycomb. The web is usually welded, brazed, or otherwise fastened to the face sheets.
[0004] The applications for these types of honeycomb structures are numerous. A main difficulty with the structures, however, is that they are cumbersome and inefficient to manufacture. For example, a honeycomb drum for use in the non-woven industry, e.g. to make baby diapers, has been formed using heavy aluminum castings which must be extensively machined. Framed honeycomb segments composed of cells of classic six-sided honeycomb are bolted to the machined castings and the outer diameter surface of the honeycomb is machined. A micro-etched screen is welded to the exposed outer honeycomb surface to create the desired vacuum-forming surface. The drum typically includes ribs traversing its width that may be as much 0.150″-0.200″ thick in a typical drum of about 2′ diameter to support loads imposed upon the drum. Because of this, the drum may weigh as much as 250 lbs., making it cumbersome for handlers.
[0005] Accordingly, there is a need in the art for lightweight cell structure that may be constructed by simple fabrication techniques.
SUMMARY OF THE INVENTION
[0006] A joint consistent with the present invention includes a first metallic member with a first opening having a body portion and extending portion. A second metallic member having a second opening is disposed in the first opening of the first member so that the second opening at least partially overlaps the body portion to create a joined opening. A bonding agent, e.g. adhesive, is applied in the joined opening so that when cured, it forms an integral part of the joint.
[0007] A slot-to-slot joint consistent with the invention includes each metallic member equipped with a slot. Each slot has a body portion and extending portion. The two members are slid together so that their respective body portions at least partially overlap to define a joined area where a boding agent may be applied. Alternatively, each member may be additionally equipped with a cutout aligned with each slot so that the cutout from the first member at least partially aligns with the body portion from the second member and vice versa.
[0008] A tab-to-slot joint consistent with the present invention includes a first metallic member with a tab having a cutout at least partially disposed within the tab. A second member has a slot that includes a body portion and extending portion. The tab of the first member is inserted into the slot of the second member so that the cutout at least partially overlaps the body portion to define a joined opening where bonding agent may be applied.
[0009] A drum laser cut from metallic sheets includes a plurality of annular members joined by a plurality of ribs via different joints such as slot-to-slot and tab-to-slot joints. A mechanical housing includes a cell structure sandwiched between first and second metallic plates. Methods of forming joints are also disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Advantages of the present invention will be apparent from the following detailed description of exemplary embodiments thereof, which description should be considered in conjunction with the accompanying drawings, in which:
[0011] [0011]FIG. 1 is a perspective view of an exemplary drum consistent with the present invention;
[0012] [0012]FIG. 2 is an interior perspective view of a portion of the exemplary drum of FIG. 1;
[0013] [0013]FIG. 3 is a cross-sectional line view taken along the line 3 - 3 of FIG. 1;
[0014] [0014]FIGS. 4A and 4B are perspective views of slotted plates illustrating an exemplary slot-to-slot connection consistent with the present invention;
[0015] FIGS. 5 A- 5 C are perspective views of a slotted and tabbed plate illustrating an exemplary tab-to-slot connection consistent with the present invention;
[0016] [0016]FIG. 6 is a plan view of an exemplary first annular A-plate with one set of radial slots for accepting primary rib members in a tab-to-slot connection;
[0017] [0017]FIG. 7 is a plan view of an exemplary second annular B-plate with two sets of radial slots for accepting primary and secondary rib members in tab-to-slot connections;
[0018] [0018]FIG. 8 is a plan view of an exemplary third annular C-plate with radial slots for accepting primary rib members in a slot-to-slot connection;
[0019] [0019]FIG. 9 is a plan view of an exemplary fourth annular D-plate with radial slots for accepting secondary rib members in a slot-to-slot connection;
[0020] [0020]FIG. 10 is an elevation view of a cellular support structure;
[0021] [0021]FIG. 11 is a cut away perspective view illustrating connection of a screen to the scalloped edge cellular support structure of FIG. 10;
[0022] [0022]FIG. 12 is a cross section view of a second embodiment of the present invention;
[0023] FIGS. 13 A- 13 D are plan views of exemplary plates for use in the second embodiment of FIG. 12;
[0024] FIGS. 14 A- 14 D are plan views of exemplary ribs for use in the second embodiment of FIG. 12; and
[0025] [0025]FIG. 15 is a plan view of a cell like rib structure for use in the second embodiment of FIG. 12.
DETAILED DESCRIPTION
[0026] Referring to FIG. 1, there is shown an exemplary flow through drum consistent with the present invention. The drum 1 includes an interior surface 3 that defines a large aperture 7 and an exterior surface 5 .
[0027] The exemplary drum 1 is generally comprised of four annular slotted plates, the A-plate 10 , B-plate 12 , C-plate 14 , and D-plate 16 , which are coupled via a plurality of primary slotted ribs 18 and secondary slotted ribs 20 arranged orthogonal to the annular plates and generally parallel with the axis of rotation A. The connections between the ribs and the plates are either slot-to-slot connections or tab-to-slot connections.
[0028] Generally, rib connections to the outermost plates are tab-to-slot connections while rib connections to the inner plates are slot-to-slot connections. More particularly, the primary rib 18 may be connected to the C-plate 14 via a slot-to-slot connection, to the B-plate 12 via a tab-to-slot connection, and to the A-plate 10 via a tab-to-slot connection. Similarly, the secondary rib 20 may be connected to the D-plate via a slot-to-slot connection, and to the B-plate 12 via a tab-to-slot connection.
[0029] Turning to FIG. 2, a cut away perspective view of the interior side 3 of the exemplary drum 1 of FIG. 1 is illustrated to show the relationship between the various plates and ribs. As illustrated, the A-plate 10 is the outermost annular plate having a radial length LA slightly less than the radial length LB of the B-plate 12 . The A-plate is the outermost plate on both the first side 9 and second side 11 of the drum 1 . The A-plate may include a plurality of slots 22 having a radial length LA 1 and width WA 1 to accept the narrower tab 61 (FIG. 6) of the primary rib 18 in a tab-to-slot connection. The A-plate 10 may also be equipped with a plurality of holes 24 for accepting bolts or other such fastening means to affix the A-plate to the C-plate 14 , which may include a nut for receiving both.
[0030] The B-plate 12 is the next outermost plate on both the first 9 and second ends 11 of the drum 1 . The B-plate may also be equipped with a plurality of slots having a radial length longer than the radial length LA 1 of the A-plate slots for accepting the wider slot end 63 (FIG. 6) of the primary ribs 18 in a tab-to-slot connection.
[0031] The C-plate 14 is an interior annular plate. Generally, the radial length LC of the C-plate 14 is greater than the radial length of the A-plate LA and B-plate LB. In the exemplary drum 1 , there are two C-plates 14 , which are coupled to a plurality of generally rectangular shaped primary ribs 18 via slot-to-slot connections 19 . The ends of the primary ribs are also joined to the A-plates 10 and B-plates 12 on the first 9 and second 11 end of the drum via tab-to-slot connections. Hence, the A-plate 10 , the B-plate 12 , and the C-plate 14 are all coupled to the plurality of primary ribs 18 . It should be understood by those skilled in the art that there may be any number of plates and ribs based on the particulars of the desired application without departing from the scope of the present invention.
[0032] Turning to FIG. 3, a cross sectional view of the exemplary drum taken along the line 3 - 3 of FIG. 1 is illustrated. A primary rib 18 is connected to two interior C-plates 14 via slot-to-slot joints. Both sides of the primary rib 18 include a wide and narrow tab structure for connecting to the outer B-plates 12 and A-plates 10 respectively via tab-to-slot connection. A plurality of D-plates 16 are disposed above the primary rib 18 and engage secondary ribs 20 via slot-to-slot joints.
[0033] Turning to FIGS. 4A and 4B, an exemplary slot-to-slot joint is illustrated. Only a piece of each member to be joined is illustrated for clarity. The representative members to be joined are the primary rib 18 and the C-plate 14 . Since only a small section of the C-plate is shown for ease of reference, it is shaped generally rectangular as opposed to the true annular C-plate shape as illustrated in FIGS. 1 & 8. Alternatively, the secondary rib 22 and the D-plate 16 may also be joined in similar fashion. Those skilled in the art will recognize that a host of other varying members may be joined using the exemplary slot-to-slot configuration illustrated in FIGS. 4 A- 4 B without departing from the spirit and scope of the present invention.
[0034] A slot 40 may be cut using laser sheet cutting technology in the primary rib 18 . Laser sheet cutting of metallic parts is a conventional technology.
[0035] The slot 40 comprises a first narrow extending section 26 , a second wider body section 28 , and a third narrow extending section 30 of substantially equal dimensions as the first section 26 . The first section may have a width W 1 substantially equal to the width W 4 of the C-plate 16 to be coupled thereto.
[0036] The width W 2 of the second body section 28 is greater than the width of the first extending section 26 . A cutout 32 has a width W 3 that may be substantially similar to the width W 2 of the second body section 28 . The length of the first extending section 26 , second body section 28 , third extending section 30 , and the cutout 32 may all be substantially equal to LC/6.
[0037] Turning to FIG. 4B, the primary rib 18 and C-plate 14 are aligned at right angles to each other and the primary rib 18 is inserted into the C-plate using this slot-to-slot configuration. The C-plate has a slot and cutout structure to match the earlier structure described with reference to the primary rib 18 . The primary rib may be inserted into the C-plate 16 until the uppermost portion 33 of the third slot section 30 abuts with the same corresponding section of the C-plate slot.
[0038] As such, the cut out 32 of the primary rib 18 is juxtaposed with the second body section 28 of the C-plate 16 at right angles to each other to form a cross-shaped open area 34 . Similarly, the second body section 28 of the primary rib 18 is juxtaposed with the cutout 32 of the C-plate 16 at right angles to each other to form a second cross-shaped open area 36 . Each of the cross-shaped open areas 34 , 36 have four extensions with a length substantially equal to LC/6, a width substantially equal to the difference between W 2 and W 1 , and a thickness substantially equal to W 4 .
[0039] Advantageously, each of these two cross-shaped open areas 34 , 36 permits a bonding agent to be inserted thereto. Those skilled in the art will recognize adhesive may be utilized as such bonding agent or any number of materials may be soldered to act as the bonding agent. When allowed to dry or cure, the bonding agent acts as an integral part of the joined members. As such, the resulting slot-to-slot joint relies upon the generally higher shear strength of the bonding agent as opposed to generally lower peel strength.
[0040] Turning to FIGS. 5 A- 5 C, an exemplary tab-to-slot joint that also creates an open area for bonding agent to be applied is illustrated. The tab-to-slot connection may be used to join primary ribs 18 and secondary ribs 20 to outermost plates such as A-plates 10 and B-plates 12 . The illustrated members to be joined in FIGS. 5 A- 5 C are the A-plate 10 and the primary rib 18 . Only a small section of the A-plate is shown for ease of reference and hence it is shaped generally rectangular as opposed to the true annular A-plate shape as illustrated in FIGS. 1 & 6. Those skilled in the art will recognize that a host of other members may be joined using the exemplary tab-to-slot configuration illustrated in FIGS. 5 A- 5 C without departing from the spirit and scope of the present invention.
[0041] [0041]FIG. 5A illustrates a slot 50 having a first extending portion 52 , a second body portion 54 , and third extending portion 56 slot with respective widths W 1 , W 2 , and W 3 . The length L 1 of the slot 50 may be substantially equal to the length L 2 of the tab 59 so that the tab securely fits in the slot. The width W 5 of the tab 59 may also be substantially equal to the width W 6 of the A-plate 10 so that the tab 59 is flush with the A-plate 10 after insertion. The tab 59 may also be equipped with a cutout 58 . The length of the cutout 58 on the primary rib 18 may be substantially equal to the length of the second body portion 54 on the A-plate 10 .
[0042] Turning to FIG. 5C, the primary rib 18 may be orientated at a right angle to the A-plate 10 so that the tab 59 may be coupled to the slot 50 . The coupling of the tab into the slot results in the cutout 58 being juxtaposed with the second body portion 54 of the slot 50 at right angles to each other to form a cross-shaped open area 57 . The cross-shaped open area 57 has four extensions with a length substantially equal to L 1 /3, a width substantially equal to the difference between W 2 and W 1 , and a thickness substantially equal to W 6 . Those skilled in the art will recognize that a plurality of open areas with varying geometries and dimensions may be employed in a slot-to-slot connection or tab-to-slot connection without departing from the scope and spirit of the present invention. Although the width of the slots may also vary, the laser cutting function can permit the width of the slots to be as narrow as 0.06 inches.
[0043] Advantageously, the cross-shaped open area 57 permits a bonding agent to be inserted thereto and allowed to cure. The cured bonding agent then acts as an integral part of the joined members. As such, the resulting tab-to-slot joint relies upon the generally higher shear strength of the cured bonding agent as opposed to generally lower peel strength.
[0044] Turning to FIG. 6, the A-plate 10 may be cut from a sheet of material 60 . The A-plate 10 may have a plurality of radial slots 22 for accepting the narrower tabbed ends 61 of a plurality of primary ribs 18 . The A-plate may also have apertures 24 for accepting bolts or other such fastening means to attach the C-plate to the A-plate. Primary ribs 18 may be cut from the mid area of the sheet 60 or another separate sheet. The primary ribs may also have a wider tab portion 63 . The wider tab 63 accepts the B-plate 12 up against the abutting edge 65 of the wider tab 63 .
[0045] Turning to FIG. 7, the annular B-plate 12 may be cut from a sheet 62 , and primary ribs 18 may be cut from the center of the sheet. The B-plate 12 may have a first set of radial slots 70 and a second set of concentric radial slots 72 . The first set of interior slots 70 may be sized to accept the wider tab 63 from the primary ribs 18 . The second set of exterior slots 72 may be sized to accept tabs from the smaller secondary ribs 20 . The secondary ribs 20 form a cell structure with the D-plates 16 as described more fully with reference to FIG. 10 and illustrated generally in FIG. 1.
[0046] Turning to FIG. 8, the annular C-plate 14 may be cut from a sheet 80 and primary ribs 18 may be cut from the center of the sheet. A plurality of radial slots 82 may be cut in the C-plate 14 to present openings along the outside circumference 84 of the C-plate. The radial slots 82 may be sized to accept the slots 86 cut into the primary ribs 18 for establishing a slot-to-slot connection between the C-plate and the primary ribs 18 . The slot-to-slot connection may also be as described earlier with reference to FIGS. 4A & 4B.
[0047] Turning to FIG. 9, the annular D-plate 16 may be cut from a sheet 90 and secondary ribs 20 may be cut from the center of the sheet. The D-plate may be cut with a plurality of radial slots 98 . The radial slots 98 may be arranged in an alternating pattern having two radial slot openings on the outside circumference 96 of the D-plate followed by a radial slot opening on the inside circumference 99 .
[0048] The secondary ribs may include secondary B ribs 20 a and secondary C ribs 20 b each having a plurality of slots 94 sized to engage corresponding radial slots 98 of the D-plate in a slot-to-slot configuration. The secondary B-ribs 20 a couple to the D-plate via insertion over the outer circumference 96 while the secondary C ribs 20 b couple to the D-plate via insertion by the inner circumference 99 .
[0049] Turning to FIG. 10, a small section of a modified cell structure 100 is illustrated. The cell structure 100 is comprised of pieces of the annular D-plates 16 and secondary ribs 20 , each having scalloped edges 102 , connected via slot-to-slot joints 19 . A screen 104 may be affixed to the scalloped edges as can be best seen in FIG. 11. The screen may be resistance welded to the scalloped edges. In this instance, the cell structure that is snapped together utilizing a slot-to-slot joint would not require any bonding agent to be used in the slot-to-slot joints. The scalloped edges 102 maximize the open area between the cellular structure 100 and the screen 104 .
[0050] Turning to FIG. 12, a second embodiment consistent with the present invention is illustrated. The second embodiment is a housing 1200 made up of a plurality of sandwiched structures with brazed joints, where each structure may include an exterior plate and an interior plate sandwiching a plurality of ribs. Such housing structures are strong and lightweight and may be utilized in the aircraft industry to enclose sensitive equipment, e.g. electronic equipment. Those skilled in the art will also recognize that a single sandwiched structure may be utilized to form various support structures used in a variety of applications, e.g. floors and wall support in aircraft.
[0051] A perspective cross sectional view of one corner of an exemplary housing 1200 is illustrated in FIG. 12. One wall 1201 is joined to a ceiling 1203 at a corner. Similarly, a plurality of different walls, ceilings, and floors may be joined at different corners to create an enclosed housing. The wall 1201 may include an exterior wall plate 1202 connected to an interior wall plate 1206 via a plurality of ribs. Similarly, the ceiling 1203 may include an exterior ceiling plate 1204 connected to an interior ceiling plate 1208 via a plurality of ribs. Advantageously, the exterior ceiling plate 1204 includes a plurality of notches 1302 to accept corresponding tabs 1304 from the exterior wall plate 1202 to form an integrated exterior edge. Similarly, the interior ceiling plate 1208 includes a plurality of notches 1306 to accept corresponding tabs 1308 from the interior wall plate 1206 .
[0052] Turning to FIGS. 14 A- 14 D and FIG. 15, the plurality of ribs and an exemplary cell configuration of ribs that may be sandwiched between the exterior and interior plates is illustrated. For ease of explanation, the plurality of ribs includes a set of vertical ribs 1502 and horizontal ribs 1504 with respect to the plates of FIGS. 13 A- 13 D. The set of vertical ribs 1502 includes a standard vertical rib 1212 and a tabbed vertical rib 1210 , while the horizontal ribs 1504 includes a standard horizontal rib 1216 and a tabbed horizontal rib 1214 . Due to laser cutting, the ribs may be only 0.006 inches thick aluminum in this embodiment and the exterior and interior plates may be 0.063 inches thick aluminum.
[0053] The slots 1404 of the standard vertical rib 1212 engage corresponding slots 1410 of the horizontal ribs 1214 , 1216 . One set of tabs 1402 of the tabbed vertical rib 1210 protrude at right angles with respect to the length of the rib. These right angle tabs 1402 engage corresponding slots 1312 in the exterior plates 1202 , 1204 (FIGS. 13 A- 13 B). The other tab 1406 of the tabbed vertical rib 1210 engages a separate slot 1314 on the exterior plates 1202 , 1204 when adjacent exterior plates are joined together at right angles.
[0054] Turning to FIGS. 14C and 14D, the horizontal set of ribs 1504 is illustrated. The standard horizontal rib 1216 includes a plurality of slots 1410 that engage corresponding slots 1404 in the vertical ribs. The tabbed horizontal rib 1214 may include a plurality of tabs 1408 that engage corresponding slots 1314 in the interior plates.
[0055] Turning to FIG. 15, the horizontal ribs 1504 and the vertical ribs 1502 may be arranged orthogonal to form a square cell like structure. Those skilled in the art will recognize that other structures such as honeycomb structures may also be utilized without departing from the spirit and scope of the present invention.
[0056] The tabbed horizontal rib 1214 is arranged periodically among the standard horizontal ribs 1216 so that its tabs 1408 properly engage slots 1314 in the interior plates. Similarly, the tabbed vertical rib 1210 is periodically arranged among the standard vertical ribs 1212 .
[0057] Advantageously, the entire housing structure may be assembled with slot-to-slot joints and tab-to-slot joints as earlier described. Again, generally the horizontal ribs 1504 and the vertical ribs 1502 engage each other in slot-to-slot joints 1506 , while the exterior and interior plates are joined to the cell like structure via tab-to-slot joints. The joints may be brazed through techniques known to those skilled in the art.
[0058] The embodiments that have been described herein, however, are but some of the several which utilize this invention and are set forth here by way of illustration but not of limitation. It is obvious that many other embodiments, which will be readily apparent to those skilled in the art, may be made without departing materially from the spirit and scope of the invention as defined in the appended claims. | A joint for metallic members including a body portion and extending portion in one member and an opening in a second member. The body portion of one member at least partially overlaps the opening in the second member to create a joined opening. A bonding agent, e.g. adhesive, is applied in the joined opening to create a strong joint relying on the sheer strength of the cured bonding agent rather than its peel strength. Slot-to-slot and tab-to-slot joints using joined openings are provided. A drum and mechanical structure constructed using laser cutting techniques on metallic plates and utilizing the disclosed joints are also provided. | 8 |
A photodiode is connected directly to a signal conditioning circuit which rapidly removes unwanted asynchronous ambient background light signals such as from sunlight, by means of a switched ambient light subtractor circuit. The signal current after cancellation of the ambient background signal is sampled in an integrate and hold circuit to provide a heart systolic pressure wave or envelope of the pulse amplitudes. The synchronous steady state IR pulse carrier envelope signal is cancelled by a perfect second-order feedback loop via an integrating amplifier and a switched transconductance element that operates with fast response, even under conditions of large overloads that occur at the sensor. The second-order feedback loop because of various restraints, necessarily has a long differentiation time constant. The pole zero cancellation circuit which is included in an amplifier circuit cancels the long differentiation time constant so as to remove undesired shaping of the heart pressure wave caused by the second-order loop. Thus, a heart pressure wave which has been shaped by a double differentiation with only a short time constant is provided at the output of the amplifier circuit. Pulses of the heart systolic pressure wave are then detected with a high degree of timing accuracy to determine the pulse rate which is then displayed.
BACKGROUND OF THE INVENTION
This invention is related to pulse rate measurement systems, and particularly to an improved pulse rate measuring system that includes input coupled pole zero cancellation to rapidly and accurately develop pulse rate readings.
In a patent application, Ser. No. 965,816, entitled Heart Rate Measurement System, invented by Lanny L. Lewyn and filed Dec. 5, 1978, the same inventor on this application, a pulsed IR plethysmograph was disclosed and claimed having a photodiode and a gated circuit connected thereto for pulse-by-pulse cancellation of the asynchronous ambient light components of the photocurrent signal. A switched integrate and hold circuit was provided to respond to the current signal after ambient light cancellation to provide a signal representive of the blood pressure modulation. A switching transconductance element, an integrating operational amplifier and the integrate and hold circuit were included in a perfect second-order feedback loop to develop current pulses for cancellation of synchronous IR carrier steady state photocurrent resulting from the pulsed light source. Because of the size restraints on certain elements in the system and the objective of keeping individual stage DC gains low, especially in a watch, the differentiation in the perfect second-order loop necessarily had a relatively large time constant. The result of this long time constant differentiation was an undesirable shaping effect on the heart pressure wave at the output of the loop so that the amount of pulse rate uncertainy was greater than might have been desired. An arrangement as shown and described in the above-referenced patent application that would remove the effect of this long time constant third differentiation and result in a system with only double differentiation with a short time constant would be a substantial advance to the art.
Pole zero cancellation is generally known in network theory, at least as to remaining poles at the limits, as discussed in the book by E. A. Guillermin, Synthesis of Passive Networks, John Wiley and Sons, Inc., New York, 1957. Also, in the nuclear field, pole zero cancellation has been applied to some of the problems of pulse shaping in nuclear pulse amplifiers, as discussed in a paper by C. H. Nowlen and J. L. Blankenship published starting with page 1830 in the Review of Scientific Instruments, 1965 edition, Vol. 36, No. 12. This paper shows a system operating with a charge sensitive preamplifier that has overload conditions resulting from high energy particles that deposit a large amount of energy on the detector causing the charge sensitive preamplifier to go into an overload condition. The pole zero cancellation in in the system of the paper is to cancel the effect of the slow recovery of the charge sensitive preamplifier so that information can be reliably extracted from a single pulse. The objective of applicant's compensation by pole zero cancellation is different than taught in the prior art in that Applicant's system operates with DC coupling to a perfect second-order loop which has the purposes of suppressing the individual pulse of the pulse carrier and extracting only the information from variations in pulse-to-pulse amplitude. Thus, Applicant's compensation operates in a time frame that is slow compared to the pulse-to-pulse time interval. In contrast to Applicant's system, the nuclear pulse amplifier system of the paper uses pole zero cancellation to discard the remnants of a pressure pulse so that the system is totally cleaned when the next pulse is received. Further, Applicant's invention is to prevent excess noise and an undesirable shaping effect in the heart blood pressure wave which would lead to improper timing information while the pole zero cancellation in the paper is used primarily for measuring pulse amplitude rather than time. Accordingly, Applicant's type of compensating circuit including its function, is direct coupling to the signal source and its arrangement in conjunction with a perfect second-order loop input is not taught in the prior art.
SUMMARY OF THE INVENTION
In an exemplary embodiment of the invention, a pulsed IR reflectance plethysmograph for heart rate measurement includes a signal processing circuit providing a heart pressure wave that is filtered with a differentiation having a relatively large time constant because of the restraints on the component values such as resulting from the chip size in a digital watch. To overcome this long time constant differentiation, a novel amplifier arrangement is directly coupled to the signal processing circuit and includes a pole cancelling arrangement to effectively substitute a short time constant differentiation for the long time constant differentiation. To avoid high gain DC coupling in the amplifier, two short time constant coupling networks must be used. Triple differentiation produces undesireable signal shaping and signal-to-noise characteristics. Therefore, the input signal processing circuit differentiation must be cancelled and it is simpler to accomplish this if it has a long differentiation time constant rather than a short one. The system has a pulsed light source applying the pulses of light to a finger, for example, for reflection to a detector such as a photodiode. A gated circuit is connected directly to the photodiode for pulse-by-pulse cancellation of the asynchronous ambient light components of the photocurrent signal. A switched integrate and hold circuit is provided to respond to the current signal after ambient light cancellation to develop a signal representative of the blood pressure modulation. A perfect second-order loop is formed including the integrate and hold circuit, an integrating operational amplifier and a switched transconductance element, and develops current pulses for cancellation of synchronous IR carrier steady state photocurrent resulting from the pulsed light source. The integrating operational amplifier includes a resistor R B and a capacitor C B for providing the differentiation time constant to the system response. The amplifier and filter circuit includes an operational amplifier directly coupled to the integrate and hold circuit through a differentiating capacitor and resistor. A bypass resistor R 3 is coupled in parallel to the differentiating capacitor C 1 to provide a time constant R 3 C 1 equal to R B C B . The bypass resistor R 3 provides a zero to cancel the pole caused by the R B C B differentiation with the result that a short time constant differentiation (R 1 ∥ R 3 ).C 1 is substituted for the large time constant differentiation. As a result, the shaped heart wave signal amplifier output has a high degree of systolic pressure wave pulse-to-pulse timing accuracy and a reliable pulse interval can be detected for displaying the pulse rate.
It is therefore an object of this invention to provide an improved pulse rate measurement system.
It is a further object of this invention to provide a plethysmograph for heart rate measurement that rapidly provides a substantially accurate pulse count.
It is another object of this invention to provide a circuit for a pulse watch that maintains high AC gain in each stage while holding DC stage gain low and yields double differentiation shaping instead of the triple differentiation shaping which would otherwise be the result of AC coupling three high gain stages.
It is another object of this invention to maintain low DC stage gains within the component size limitations imposed by the constraints of a circuit which is mounted on a wristwatch.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects, features and advantages of the invention itself, will become apparent to those skilled in the art in the light of the following detailed description taken in consideration with the accompanying drawings, wherein like reference numerals indicate like corresponding parts throughout the several parts wherein:
FIG. 1 is a schematic block diagram of a pulsed IR reflectance plethysmograph system for heart rate measurements illustrated in a wristwatch as an example of one use of the system in accordance with the invention;
FIG. 1a is a schematic circuit and block diagram showing a sensor and the current conditioning section of FIG. 1 in further detail;
FIG. 2 is a schematic circuit diagram of the asynchronous ambient light cancellation circuit shown in the system of FIGS. 1 and 1a;
FIG. 3 is a schematic circuit diagram of the switched capacitor transconductance element shown in a perfect second-order feedback loop in the system of FIGS. 1 and 1a for synchronous steady state pulse carrier light cancellation;
FIG. 4 is a basic logic timing diagram for the system of FIG. 1;
FIG. 5 is a specific logic timing diagram for the circuits of FIGS. 2 and 3;
FIG. 6 is a schematic diagram of waveforms of voltage and current as a function of time for further explaining the operation of the system of FIGS. 1 and 1a;
FIG. 7 is a schematic diagram of voltage as a function of time illustrating a typical systolic blood pressure waveform developed by the signal conditioning circuit (Block 24) and the amplifier and bandpass filter (Block 26) of FIG. 1; and the pulse train that is derived from the threshold disciminator (28) of FIG. 1;
FIG. 8 is a schematic circuit and block diagram of an amplifier and bandpass filter of FIG. 1 including the pole-zero cancellation system in accordance with the invention;
FIG. 9 is a schematic drawing of diagrams the output to input voltage ratio in decibles as a function of log f for explaining the amplifier and bandpass filter of FIG. 8; and
FIG. 10 is a schematic diagram of waveforms of voltage as a function of time for further explaining the operation of the amplifier and bandpass filter of FIG. 8 with the pole-zero cancellation system in accordance with the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIGS. 1 and 1a, one embodiment of the invention is incorporated in a plethysmograph adapted to fit in the case of a digital wristwatch for use in field measurements of heart rate, such as by a jogger immediately upon stopping, or while resting, for use by a person who must measure his heart rate frequently, or for use by medical or related personnel. It is to be understood that the principles of the invention are not limited to wristwatches but also apply to instruments that may have other forms such as those that may be desirable for field or hospital uses. More particularly, the illustrated system which includes the compensating combinations of the invention, is a heart rate measurement device which uses the IR reflectometer principle for peripheral pulse measurement by sensing volumetric variations of the capillaries of the fingers or of any tissue with sufficient capiliary development to provide a useful light absorption signal. It is to be noted that the system in which the invention is incorporated includes operation at any suitable IR or other wavelengths at which there is suitable penetration through tissue to respond to the blood pressure variations and is not be limited to any particular wavelength band. The illustrated system utilizes an infrared (IR) light emitting diode (LED) 10 to provide a pulsed source of IR light which is reflected off of the tissues of the finger, for example, and onto a photodiode detector diode 12 having a photocurrent response characteristic. The peripheral systolic wave causes an abrupt increase in IR light absorption (the reflectance drops) by the capillaries of the finger which dilate in response to the systolic pressure wave. The small (˜2%) changes or modulation in reflected light amplitude is sensed by the photodiode 12 along with the steady state component of the reflected IR light pulse train plus ambient light from any other source such as sunlight or indoor lighting. To avoid the problems of an LED drive feedback system, the LED 10 is driven in an open loop with constant current pulses so that the LED drive and front end gains are therefore set at optimum levels and these levels do not and need not change as a result of beackground lighting conditions or tissue reflectivity. The LED 10 is driven at a fixed rate set by timing or clock pulses φ 4 . A crystal oscillator and pulse system timing generator 14 provides the timing pulses φ 4 which are typically at 73 Hz (to insure that the beat frequencies between the 73 Hz sampling frequency and the indoor lighting frequencies are well above the system passband) to a base current pulse generator 16, which in turn applies pulses to the base of an NPN type drive transistor Q 1 . The emitter of the transistor Q 1 is coupled to a negative supply voltage, -V, and the collector is coupled through a resistor R 1 to the cathode of the LED 10. The anode of the LED 10 is coupled through a lead 13 to the positive supply voltage, +V, and to the cathode of the photodiode 12 which in turn has its anode coupled to a lead 15. A resistor R 2 is connected to the +V supply (lead 13) and to the lead 15. The transistor Q 1 conducts pulses of current through the LED 10 and through the current limiting resistor R 1 when an analog power control signal φ A is turned on. A digital watch timing and pulse rated computation section 18 of a digital watch provides the control signal φ A to the timing generator 14 once the operator depresses a push button switch 20. When the switch 20 is depressed a second time, the control signal φ A is then turned off. The LED 10 in the illustrated watch system, is mounted in a small sensor 22 illustrated as a dotted box on the face of the watch to pass or transmit IR pulses to the surface of a finger 23, for example, of the person whose pulse rate is being monitored. The IR pulses reflected off the tissue and capillaries of the finger 23 are received by the photodetector 12, also mounted in the sensor 22. The timing generator 14 which responds to a crystal oscillator as is well known in the art, provides the timing signal φ 4 as well as timing signals φ 1 and φ 2 for use in the system. Also, the timing generator 14 applies suitable signals such as a 32 KHz clock signal and 1024 Hz signal to the computation section 18.
An input signal current conditioning section 24 directly coupled to the photodiode anode through the lead 15, cancels asynchronous ambient light (sunlight, or artificial light as well as other light asynchronous to the system) and synchronous steady state components of the LED light pulse carrier. The output of the signal conditioning section 24 passes through a node 25 to an amplifier and bandpass filter 26 as a heart pressure wave voltage having systolic pulses occurring at a rate that is typically 60 to 80 per minute but which can also be as high as 199 pulses per minute. The amplifier and bandpass filter 26 includes the compensating arrangement that in combination with the section 24 provides the highly accurate pulse counting system in accordance with the invention. A voltage level discriminator 28 which provides a comparison of the heart pressure wave voltage relative to the threshold voltage VR 5 , detects these systolic pulses from a signal provided by the amplifier and bandpass filter 26, and transmits a pulse train of rate determining pulses to the digital watch timing and pulse rate computation section 18 which detects the time (T) between the edges such as the positive going leading edges of the systolic pulses in the train, and computes the pulse rate R (R=I/T, with I=the total timing interval). The type of computations provided by the section 18 is well known in the digital art and need not be explained in further detail. The pulse rate R is then displayed as a decimal number by a digital watch display section 30.
A suitable power supply such as a battery power supply 31 is provided and may include a pair of batteries (not shown) that together provide a voltage of approximately 3.2 volts between the voltages +V and -V as utilized in the illustrated heart rate monitoring system in a watch. The power supply 31 also provides voltages VR 4 , VR 5 and VR G . The voltage VR 5 for the discriminator 28 is provided for example, by a series string of five diodes, coupled between +V and a constant current generator source with the voltage VR 5 being provided at the cathode of the diode that is coupled to the constant current source. The voltage VR 4 is the voltage at the anode of the last diode that is coupled to the constant current source. It is to be noted that the discriminator 28 triggers on any signal from the amplifier and bandpass filter 26 that exceeds the difference between the discriminator reference voltage VR 5 and the amplifier quiescent output voltage VR 4 . The voltage VR 4 -VR 5 is typically one diode drop or approximately 0.5 volts.
The input current conditioning section 24 includes an asynchronous ambient light cancellation circuit 32 coupled to the lead 15 to receive a photocurrent i 3 which is a current i 1 as provided by the photodiode 12 (and a small current i 6 from the diode bias resistor R 2 ) combined at a node 41 with the synchronous carrier supression current i 2 . The ambient light current cancellation circuit 32 also receives the reference voltage VR G and the timing pulses φ 1 and φ 2 for providing carrier cancellation during the sampling pulse periods, and applies an output current i 5 on a lead 33 to an integrate and hold circuit 34. Gates G 3 and G 7 , an integrate and hold capacitor C c and a unity gain amplifier 43 are all included in the integrate and hold circuit 34. The gate G 3 responsive to timing signal φ 1 for being biased into conduction is coupled between the lead 33 and a node 37 which in turn is coupled to a positive input terminal of the unity gain amplifier 43. The capacitor C c is coupled between a +V terminal and the node 37 to provide integration of the signal for applying a blood pressure wave to the node 25. A gate G 7 is coupled between the lead 33 and the negative feedback input terminal of the unity gain amplifier 43, as well as to the node 25. The gate G 7 is biased into conduction in response to the timing signal φ 2 to prevent the parasitic capacitance in the circuit at the lead 33 from being charged during the interval between LED pulses.
A perfect second order feedback loop 39 includes an operational integrator 38, a resistor R A , an integrating capacitor C B , a stabilizing resistor R B , an integrating operational amplifier 42, and includes a switched capacitor transconductance element 40, for providing the current i 2 to or from the node 41 at the lead 15. The resistor R A is coupled between the node 25 and a negative feedback terminal of the amplifier 42, with the negative terminal feedback being derived serially through the integrating capacitor C B and the stabilizing resistor R B in turn coupled to a lead 47 at the output of the amplifier 42. A high frequency bypass capacitor 49 is connected across the resistor R B . A reference voltage VR 4 is applied to the positive input terminal of the operational amplifier 42. The switched capacitor transconductance element 40 receives the amplifier 42 output signal V f on the lead 47, the reference voltage VR 4 and the timing pulses φ 1 and φ 2 , to provide the i 2 correcting current to the node 41 which cancels the steady state component of the synchronous pulse carrier as well as corrects any residual imbalance remaining after ambient light cancellation by the circuit 32.
To further explain the overall operation of the system including the combinations of the invention, the illustrated base current pulse generator 16 provides a 31 μs pulse of 2 mA to the base of the drive transistor Q 1 every 13.67 μs i.e., at a 73 Hz rate. The photodiode current is rotated to the input signal conditioning section 24 where ambient background light and the synchronous steady state component of the LED light pulse carrier are removed by cancellation. The heart pressure wave voltage signal which is the envelope of the detected photocurrent pulses, is processed by the amplifier and bandpass filter 26 to compensate for the filtering in the section 24 as well as to remove any remaining finger motion artifact signal and any background light signals which have not been completely cancelled by the input signal conditioning circuit 24. The voltage level discriminator 28 triggers on any amplifier output greater than the difference between two reference voltages VR 5 and VR 4 to apply a pulse train to the computation section 18.
The input signal conditioning section 24 will now be explained in further detail starting with the asynchronous ambient light cancellation function which is carried out by a split-drain P channel MOS field effect transistor Q 3 and the circuit of a dotted line block 48 as shown in FIG. 2. Operation of the ambient light cancellation circuit 32 may best be understood by first describing that portion of the circuit enclosed in the block 48 which functions as a "storage current mirror" to maintain drain current i 4 to a drain electrode D 1 of a split-drain N-channel MOS fieldeffect transistor (FET) Q 2 , approximately equal to the drain current i 3 /2 in a drain electrode D 2 of the split-drain P-channel FET Q 3 , so long as a transmission gate G 1 is open (conducting) and a transmission gate G 2 is closed (not conducting). The split-drain FET Q 3 has its gate electrode coupled to a voltage reference terminal VR G and its substrate biased to +V volts. The photodiode current is applied directly to the source electrode of the FET Q.sub. 3 without amplification or conversion of another electrical parameter and drain electrode D 1 thereof is directly connected to the output current lead 33. The gate G 1 responsive to the timing signal φ 2 is coupled between a gate node 49 and a node 50, the latter node being coupled between the drain electrode D 2 of the FET Q 3 and a drain electrode D 2 of the FET Q 2 . Also, a gate G 2 responsive to the timing pulse φ 1 is coupled between the negative supply voltage -V and the node 50. The drain electrode D 1 of the FET Q 2 is coupled to a node 51 and the output lead 33 and the source electrode of the FET Q 2 is coupled to the negative supply -V voltage terminal. The well of the FET Q 2 is biased by the voltage -V. A capacitor C D is coupled between the gate node 49 and the -V voltage supply. When the transmission gate G 1 is conducting, the current i 4 is equal to the drain electrode D 2 output current of the FET Q 3 , which is i 3 /2, and the potential of the node 49 follows the potential of the gate node 50. The drain current from the FET Q 3 to the node 51 is half of the current i 3 because the FET Q 2 is constructed so that both drain currents are always equal to each other when a sufficient source to drain voltage potential is maintained. The current i 3 /2 applied to the drain electrode D 2 of the FET Q 2 establishes the current i 4 in the drain electrode D 1 of the FET Q 2 during the interpulse intervals between sampling pulses, which current must be equal. It is to be noted that the capacitor C D which is coupled between the gate electrode and the source electrode of the FET Q 2 assumes a charge to bias the FET Q 2 to pass the current i 3 /2 while the gate G 1 is conducting. If the gate G 1 is closed (non-conducting) while the switch G 2 is opened (conducting) the voltage -V is applied to the node 50 so that that drain electrode D 1 of the FET Q 3 remains conducting even though the current increases. Also, the current i 4 remains at a value equal to its value just before the sample pulse period. The constant current i 4 results from the charge stored on the capacitor C D maintaining the same gate voltage across the FET Q 2 as that prior to the sample pulse period, so that the total current i 4 into the drain electrode D 1 of the FET Q 2 does not change during the sample pulse period. The -V voltage at the drain electrode D 2 of the FET Q 3 maintains that FET in the balanced split-drain mode during the sample pulse period so that the current applied to the node 51 therefrom is the i 4 current plus one-half of the additional signal current. The output current i 5 , during the sample period, is just the difference between the drain D 1 current of the FET Q 2 and the drain D 1 current of the FET Q 3 . If the i 4 ambient current remains essentially constant and the steady state pulse envelope and other imbalances are cancelled, the output current i 5 is then just one-half of the sampling period signal current (heart pressure wave). During the sample pulse period, the current into the drain electrode D 2 of the FET Q 2 is essentially zero, the drain electrode D 2 current from the FET Q 3 passing through the gate G 2 to the negative supply.
To further explain the operation including the cancellation of ambient photocurrent, when the LED pulse controlled by a timing signal φ 4 is first applied to the pulse generator 16 (FIG. 1), the gate G 1 is biased out of condition and the drain current i 3 /2 to the node 50 from the FET Q 3 increases as a result of the LED light pulse sensed by the photodiode 12 (FIG. 1). If the background (ambient) light will remain nearly constant during the brief 31-microsecond pulse (φ 4 ) that triggers the LED on, the ambient light current will be cancelled since the current i 4 remains constant (due to the stored charge on the capacitor C D ) and is equal to the ambient light photodetector current i 3 /2 applied to the node 51 between the LED pulses. The true or total LED current signal which includes the synchronous steady state sample pulse envelope is split into equal parts by the FET Q 3 , and half is applied to the node 51, the half including the current i 5 which is the current in excess of the ambient light current i 4 . The excess current i 5 charges the integrate and hold capacitor C c through the transmission gate G 3 during LED sample pulse periods.
Without the synchronous LED light cancellation circuit of FIGS. 1, 1a and 3, the LED reflected light current would quickly charge and maintain the charge on the capacitor C c and the voltage at the node 37 (FIG. 1) would be driven to and remain at a high potential close to the +V supply voltage. That high potential condition on the capacitor C c is precisely what happens a fraction of a second after the finger is placed over the window 22 (FIG. 1) of the sensor and before the synchronous carrier pulse current cancellation control loop 39 including the circuit of FIG. 3 has responded. After the switched capacitor transconductance element 40 of FIG. 3 has had time to respond, the steady state component of the reflected LED light pulse carrier, as well as any residual imbalance from the cancellation circuit of FIG. 2 or unity gain amplifier 43, are cancelled. Thus, the output current i 5 consists primarily of just the blood pressure wave photocurrent signal which, after being integrated and passed through the unity gain amplifier 43 represents the envelope of the LED pulse current. Between the LED pulses, the gate G 7 responsive to a gating pulse φ 2 is open or conductive from the node 25 to the lead 33 so that the parasitic capacitance does not charge during interpulse periods.
It should be noted that this blood pressure wave photocurrent signal, i 3 is divided in half by the split drains of the transistor Q 3 , but is applied directly to the node 51 without amplification or conversion to a voltage parameter. It should also be noted that sunlight or ambient current in an amount several thousand times greater than the blood pressure wave current can be cancelled (subtracted) by the current i 4 at the node 51, leaving a signal current i 5 in the range of a few nanoamperes to be integrated across the holding capacitor C c of a few picofarads, thereby producing a signal in the millivolt range (10 to 50 mV) without amplification. This integrate and hold technique in accordance with the invention, makes possible fast recovery times from the sudden presence and resulting overload of the reflected IR steady state light pulse carrier as the finger is placed over the sensor. This overload is cancelled by the second-order feedback loop 39 (FIG. 1a) in times ranging from 1 or 2 seconds rather than 20 to 30 seconds, and eliminates the requirement for digital initialization commands. In another arrangement in accordance with the invention, the switch G 2 may be replaced by a suitable storage capacitor to hold the voltage on the node 50 during the φ 1 or the ambient light cancellation period.
The switched capacitor transconductance element 40 will now be described in relation to the node 41 and the operational amplifier integrator 38 with reference to FIG. 3 as well as to FIGS. 1 and 1a. The object of the transconductance element 40 is to provide cancellation of any pulsed steady state synchronous light components with quick response time (1 to 2 seconds) even though the node 51 (FIG. 2) voltage may be driven to saturation, i.e., into overload. In overload, the element 40 responds with recovery times that are characteristic of the open loop response time (R A .C B rather than the closed loop response time R B .C B ). It should first be noted that one of the reasons for the fast open loop response, and a characteristic of the novel interconnection between the photodetector 12 and the second order synchronous feedback loop including the transconductance element 40, is that a small imbalance between the synchronous current components i 1 and i 2 will quickly drive the integrating capacitor C c to produce a high error voltage (nearly equal to the available supply voltage) for restoring the loop to balance.
The synchronous light cancellation loop 39 utilizes the transconductance element 40 comprised of a switched capacitor C E and two transmission gates G 5 and G 6 . The voltage VR 4 is the reference voltage applied to the capacitor C E during the LED interpulse periods in response to the switching or gating pulses φ 2 and the voltage V f is the error voltage applied to the capacitor C E during the LED pulse periods in response to the switching or gating pulse φ 1 . This switched capacitor transconductance element 40 produces an output current i 2 at the node 41 (FIG. 1) proportional to the difference in the reference voltage VR 4 and the voltage V f from the integrating operational amplifier 42. The element 40 provides an equivalent transconductance g m E of C E /T, where T is the switching period of the clock signal φ 4 , which is 13.67 milliseconds in this exemplary embodiment.
The feedback loop 39 in accordance with the invention is a second-order loop because it has two poles with the first pole being established by (1/g m E) (C c ) (R A /R B ). The second pole is equal to R B C B at the operational amplifier integrator 38. The feedback loop is a perfect second-order loop because the integrating operational amplifier 42 holds the error voltage at node 25 near VR 4 and the error voltage out of the unity gain amplifier 43 need not be increased to correct for an increase in steady state loop stress such as a change in steady state value of the pulse carrier amplitude or an imbalance of the correction provided by the ambient light cancellation circuit 32. This unique feature of the input loop allows it to be direct coupled to the pole-zero cancellation circuit without developing high DC offsets at the cancellation circuit output as might be the case in prior art systems where the input circuit was stressed with a high DC input current. The operational amplifier integrator 38 is similar to a conventional type except a phase lead is provided by the stabilization resistor R B .
The ratio R B /R A determines the high frequency attenuation feedback factor or the amplitude of the cancelling current i 2 . It is to be noted that the differentiation time constant R B C B of the feedback loop allows the high frequency components of the heart blood pressure envelope to be formed on the lead 25 as the output signal and that the loop acts to remove the low frequency motion artifact and components of the pressure envelope with the high pass time constant T H =R B C B .
It is to be understood that this differentiation in the closed loop forward transfer function is a result of a low frequency integrating operation including C B , R A and integrating operational amplifier 42 in the feedback or return path 39 of the perfect second-order control loop.
Just prior to the beginning of an LED pulse, nearly all of the current i 3 passing to the ambient light cancellation circuit 32 (FIG. 2) is photocurrent resulting from ambient light plus a current i 6 which is small bias current (a quiescent current from FET Q 3 ) flowing through the resistor R 2 (FIG. 1). At this time, the current i 4 is just equal to the input current i 3 /2 in the "storage current mirror" 48 (FIG. 2). The resulting current difference i 5 is nearly zero until light pulses are reflected by a finger being positioned over the sensor 22 (FIG. 1).
A fraction of a second after a finger is placed over the sensor, i.e., over the LED and photodetector, the LED carrier cancellation current i 2 is still at its equilibrium value, but the voltage at node 37 (FIG. 1a) is quickly driven to a high saturation value by the samll error current i 5 , which is just half of the photocurrent i 1 provided by the reflected LED light pulse carrier. As the holding capacitor C c is driven into saturation within a fraction of a second, nearly half of the total power supply voltage is applied at the output of the unity gain isolation amplifier 43 across the input resistor R A of the operational amplifier 42. Current resulting from this high fraction of supply voltage applied across the resistor R A flows through and charges the integrating capacitor C B in the feedback circuit of the operational amplifier 42. At some point in time, the charge across the capacitor C B reaches a value such that the output voltage V f from the amplifier 42 such that the current i 2 from the transconductance element 40 is equal to the reflected synchronous steady state LED light component of the current i 1 . At this point in time, the voltage at the node 37 (FIG. 1a ), i.e., across the holding capacitor C c , starts to fall rapidly and the loop closes to reach equilibrium with a closed loop time constant determined largely by R B .C B . This closed loop time constant is much shorter than the open loop time constant R A .C B since R A is usually approximately five to ten times R B for proper stabilization of the perfect second-order control loop.
Another function of the synchronous light cancellation loop 39 is to correct for any imbalance in the ambient light cancellation circuit 32 which, if not corrected, will produce a small residual component in the output i 5 passed to the integrate and hold section which is just the difference between the current i 4 and the exact current i 3 /2 required for balance. Any such residual component will result in the holding capacitor C c charging, and the resulting error voltage will charge the integrating capacitor C B until any errors are perfectly cancelled out by a change in the current i 2 . An important advantage of this second-order loop arrangement is that cancellation of i 5 imbalance current (and steady state pulse current) is achieved with negligible change in the DC differential input error voltage of the amplifier 42, and therefore the DC quiescent voltage at the output of the signal conditioning circuit 24 delivered to the amplifier and bandpass filter 26 (FIG. 1) is quite independent of large changes in ambient light conditions and held closely in value to the reference voltage VR 4 .
Referring now to the system timing diagram of FIG. 4, the clock pulse generated for the digital watch at nearly 32 kHz (actually 31,744 Hz) is first divided down to 1024 Hz, as shown by a waveform 60, and then further divided down by 14 to produce a low frequency clock at 73 Hz as shown by a waveform 62 for operation of the system in FIG. 1 as a heart pulse rate monitor. This lower rate controls the integrate and hold cycle, but only while the control signal φ A of a waveform 64 is turned on by the operator when ready to measure heart pulse rate. The next and every 14th trailing edge (1 to 0 transition) of the 1024 Hz clock of the waveform 60 initiates a 275 μs delay. The LED is then turned on for 31 μs as shown by a waveform 66. The sequence of turning on the LED at this lower rate of 73 Hz continues until the operator has read the heart pulse rate and turns the control signal φ A off.
Referring now also to FIG. 5, each time a φ 4 pulse of a waveform 67 is generated, a φ 2 pulse of a waveform 68 is generated. After a delay of about 0.1 s, a φ 1 pulse of a waveform 70 is generated, the φ 1 pulse being terminated at the end of the φ 4 pulse. The φ 2 pulse, and its compliment φ 2 of the waveform 69 terminates after the φ 4 pulse terminates to complete a pulse wave current sampling cycle. This arrangement of turning on the LED for 31 μsec at a 73 Hz rate (i.e., about every 13.7 milliseconds as shown by a 73 Hz pulse of a waveform 71) conserves power, and allows ample time between LED pulses for the background noise signal to be measured and stored in the capacitor C D (FIG. 2). Referring now also to FIG. 2, when the pulse φ 2 is low (false), the gate G 1 stops conducting. Both of the gates G 1 and G 2 are then open (not conducting for about 0.1 μs). Then the φ 1 pulse of the waveform 70 turns on the gate G 2 for control of the voltage at node 50 which would otherwise float, and also controls sampling and integrating of the reflected LED light pulse signal through the gate G 3 (FIG. 1a). It is to be noted that the gate G 7 is controlled by the pulse φ 2 of the waveform 69, so that the unity gain amplifier 43 will be disconnected prior to the sampling period φ 1 . The 0.1 μs delay in generating the φ 1 pulse allows time for the gate G 1 to disconnect before shorting the node 50 to the voltage -V through the gate G 2 , and the 0.1 μs delay in forming the φ 2 pulse after terminating the φ 1 pulse, allows time for the shorting gate G 2 to disconnect before again starting to store a charge in the capacitor C D proportional to the ambient light after the LED pulse terminates.
The feedback loop of section 24 functions as a bandpass filter with a high pass time constant T H and a low pass time constant T L where: ##EQU1## The system upper corner frequency 1/2πT L is well below any beat frequencies of sampling frequency harmonics and 120 Hz ambient light frequencies.
Referring now to FIG. 6 as well as to FIGS. 1 and 2, the system operation will be further explained including the operation of the second order control loop of the element 24. A waveform 73 shows the photodiode current i 1 and the ambient light current which is many times greater in amplitude than the current pulses. It is to be noted that the pulses of FIG. 6 which in the illustrated system are 13.67 milliseconds apart are shown with fewer pulses than actually occur during the illustrated time, for purposes of clarity of illustration. Prior to a time F, the photocurrent i 1 of the waveform 73 from the photodiode 12 consists of the ambient light level current plus a small amount of pulsed current from direct coupling between the IR LED 10 and the photodetector 12. The sensor can be constructed so that this current is quite small and in any case cancelled by the balancing current i 2 of a waveform 74 provided by the switched capacitor transconductance element 40. Thus, prior to the time F, the current i 2 of the waveform 74 removes the small steady state pulse carrier component and the ambient light component is removed by cancellation in the block 48 of FIG. 2. The resulting current i 5 of a waveform 75 has an average value of zero prior to time F. It is to be noted that the current i 5 pulses are one-half of the current pulse amplitude of i 1 in the absense of pulse cancellation. The output of the signal conditioning block 24 is provided by the unity gain amplifier 43 connected to integrate and hold capacitor C c which neither charges or discharges a significant amount at this time. The output of the amplifier 43 on the lead 25 therefore prior to time F is maintained as a steady state value around VR 4 with a small amount of flicker noise present as shown by a waveform 77.
At the time F, a finger is placed over the sensor 22 and within a small fraction of a second, the reflected IR pulse carrier has reached its full steady state value shown by the waveform 73 at a time G. The carrier cancellation current i 2 has not changed appreciately at the time G from its steady state value in this time interval from the time F as can be seen by the waveform 74. Consequently, at the time G, nearly the full amplitude carrier current (divided in two by the input split-drain device) is applied as the current i 5 to charge the integrate and hold capacitor C c .
Because the capacitor C c need be only a few (2-4) picofarads and also because there are a few (3-4) picocoulombs in each carrier pulse, the integrate and hold capacitor C c output can be driven near the positive supply voltage +V limit by just a few (2-3) carrier pulses and the output at node 25 of the unity gain amplifier 43 following the capacitor C c is also driven near the positive supply voltage limit at the same time. Because the interval between pulses is only 13.7 ms, the output can be driven into saturation within a small fraction of a second as shown by the waveform 77. Also, because the reference voltage VR 4 is midway between the supply voltages (+V and -V), the output positive swing of the waveform 77 is nearly half the supply voltage and this voltage swing is applied across the resistor R A of FIG. 1 to discharge the integgrating capacitor C B at a high rate as shown in a waveform 78 by the rapid negative slewing as the output (V f ) of the integrating amplifier 42.
As the integrating amplifier 42 slews toward the negative supply, the switched capacitor transconductance element pulsed output current (or charge) of the waveform 74 increases in direct proportion to the difference VR 4 -V f . At a time H, the pulsed output charge of the waveform 74 is just equal to the IR input carrier steady state value as shown by a level 79 of the waveform 73 representing the steady state level of the pulses. The i 5 pulsed charging current of the waveform 75 which is the difference between i 1 with ambient light removed and i 2 , therefore reaches a zero value at time H and starts to swing negative. At this time, the capacitor C c begins to discharge away from the positive supply +V and the unity gain amplifier 43 comes out of saturation as seen by waveform 77. Thus, when the current i 3 is intense because of an uncancelled steady state pulse carrier, the voltage increases rapidly at node 25, the voltage V f falls rapidly and the i 2 current increases until the integrating capacitor C c charging current i.sub. 5 swings negative at the time H in the waveform 75, resulting in a rapid drop in the output of the unity gain amplifier 43.
The rapid drop in the output voltage of the unity gain amplifier 43 terminates the negative slew of integrating amplifier 42 as shown by the waveform 78. It is to be noted that the compensation resistor R B introduces phase lead and allows the output of the waveform 78 to assume a positive slope in advance of the time that the voltage drive across R A of the amplifier 42 has reached VR 4 near the time J as can be seen at the waveform 77. Therefore, the output voltage V f from the amplifier 42 is near a final or stabilized value at time J as shown by the waveform 78.
Although the front end circuitry is settled out by the time J, some additional time is required for the following amplifiers and bandpass filter (26) to settle or stablize. This requirement of the bandpass filter is on the order of an additional 1-2 seconds so that the entire system is ready to detect the arrival of a systolic pressure wave at a time K.
A typical blood pressure waveform voltage of the waveform 77 after the time K as monitored by this integrate and hold technique at the rate of 73 Hz is shown in FIG. 7 by a waveform 80. Note that because the arrival of the pressure wave results in dialation of the capillaries and an increase in light absorption, the pressure rise (systolic) period is represented by a negative going voltage and is short compared to the pressure drop (diastolic) period. The signal conditioning section 24 performs both a short time constant (50 ms) integration and 480 ms differentiation on the true pressure waveform, but the time interval from one peak to the next remains exactly the same as for the true pressure waveform. The pulse of a waveform 81 is provided by the amplifier and bandpass filter 26 and because of the compensation provided by the pole zero cancellation has a shape relatively independent of the long time constant filtering in the section 24. Measuring the period T from one cycle to the next by detecting the peaks and timing the period between each peak of the waveform 81 thus yields a correct measurement of heart pulse rate, particularly if a running average (i.e., an average period over the last N cycles) is used to determine pulse rate as a reciprocal of the average period. Peak detection is best accomplished by the threshold discriminator 28 (FIG. 1) which converts the pressure wave voltage of the waveform 81, which is the pressure wave of the waveform 80 after amplification and bandpass filtering, to produce a pulse train of a waveform 82.
Period timing is then done by the digital watch timing and pulse rate computation section 18. The timing is done from leading edge to leading edge of each pulse in the pulse train. Pulse rate computation is simply the inverse of the average period measured, i.e., the result of the simple equation R=I/T. The rate thus computed is displayed and updated every 4 systolic intervals, for example, in such a manner as to allow each rate displayed to be clearly read before an update. If the pulse rate being monitored is steady, the average of N periods where N is typically 4, will yield an accurate and steady pulse rate reading. In practice, the operator may leave the system turned on until the rate displayed is steady, which should normally be within 10 seconds, or less.
The amplifier and bandpass filter 26 of FIG. 1, in accordance with the invention, may be the circuit as illustrated in FIG. 9 for compensating the filtering in block 24 so that the uncertainty in detecting the pulse rate at the discriminator 28 is decreased. The combination of the watch processing section 24 and the illustrated compensation arrangement as well as the compensating arrangement itself are the novel features in accordance with the subject invention. The illustrated amplifier and filter 26 includes stages 86 and 88 each providing differentiation and integration to respectively control the high pass (f H ') and low pass (f L ') corner frequencies of the passband. The signal from the block 24 at the node 25 is applied through a differentiating capacitor C 1 and a resistor R 1 to the negative input terminal of an operational amplifier A 4 having its positive input terminal coupled to the reference voltage VR 4 . The signal at the output of the amplifier A 4 is fed back through a resistor R 2 and parallel coupled capacitor C 2 to the negative input terminal thereof. A compensating resistor R 3 is coupled in parallel with the capacitor C 1 for providing a zero at f 2 to cancel the pole at the high pass frequency F H resulting from the differentiation with time constant T H =R B ·C B in the block 24.
The stage 88 includes a capacitor C 3 and a resistor R 4 serially coupled from the output terminal of the amplifier A 4 to a negative input terminal of an operational amplifier A 5 , the latter amplifier having a positive input terminal coupled to the reference voltage VR 4 . The signal at the output terminal of the operational amplifier A 5 is fed back to the negative input terminal through a parallel coupled resistor R 5 and a capacitor C 4 . The amplified and filtered signal is applied from the output terminal of the amplifier A 5 to the discriminator 28.
Referring now also to FIG. 9, an asymptotic passband diagram 89 has a high pass corner frequency f H and a low pass corner frequency f L forming the passband at the output of the block 24. The high pass and low pass frequencies are: ##EQU2## The characteristic output of the amplifier stage A 4 without the effect of the block 24 is shown by an asymptotic passband diagram 90 with a high pass corner frequency of f H '=(1/2πT d )' where T d '=(R 1 ∥R 3 )C 1 . The high pass corner frequency f L ' is selected with a greater value than the high pass corner frequency f H so that illustrated compensation may be provided. It is to be noted that the symbol means that R 1 and R 3 are in parallel. The diagram 90 has a low pass frequency f L '=(1/2πT i ) where T i =R 2 C 2 . Thus, the C 1 , R 1 , R 3 network determines the high pass frequency and the R 2 C 2 network determines the low pass frequency. At a frequency f 2 =(1/2πT 3 ) where T 3 =R 3 C 1 , the low frequency asymptote of the passband diagram 90 becomes flat to DC as shown by the solid line. The compensating resistor R 3 has the effect of adding a transmission zero which cancels the pole provided by the differentiation time constant T H of R B C B in block 24. A dotted line 91 shows the low frequency asymptote if the compensating resistor R 3 were not included in the circuit. A passband diagram 92 at the output of the amplifier A 4 has a high pass asymptote that continues at a constant +2 slope as a result of the combination of the passband of the diagrams 89 and 90. A dotted line 93 shows a +3 slope of the low frequency asymptote which would occur if the compensating resistor R 3 were not utilized.
The A 5 individual stage characteristic is shown by a passband asymptotic diagram 94 and the A 5 composite output characteristic is shown by a passband diagram 96. The high pass and low pass frequencies of the diagrams 94 and 96 are respectively f H " and f L " where f H "=(1/2πT d ") and f L "=1/2πT i ". The time constant T d "=R 4 C 3 and the time constant T i "=R 2 C 2 . It is to be noted that the high pass and the low pass frequencies of the diagram 96 may be represented by two zeros and five poles. A dotted line 97 having a +3 slope shows the attentuation that would be present in the absence of the compensating resistor R 3 .
The following are illustrative values of the time constants that may be selected:
______________________________________ T.sub.H = .48 seconds T.sub.L = .05 seconds T.sub.3 = .48 seconds T.sub.d ' = 0.1 seconds T.sub.i ' = .05 seconds T.sub.d " = 0.1 seconds T.sub.i " = .05 seconds______________________________________
The termination of the slope resulting from the differentiation at the stage 86, is a result of pole and zero cancellation. It is well known in the art that equal zero and pole terms in the respective numerator and denominator of a transfer function expression using complex notation will cancel. To further explain the slope termination, the differentiation action of R B C B in the block 24 will provide a decaying positive voltage in the time domain following the systolic pressure wave and having the time constant T H . During this decay, it is a well known property of an exponential R-C discharge that the slope (time rate of change) of the voltage will be porportional to the difference between the instantaneous value of the voltage and the quiescent or asymptotic value of the voltage. Stated in another way the ratio of the slope of the input voltage to the input voltage remains constant following an input disturbance. Since the current flow in C 1 (i 8 in FIG. 8) is proportional to the input voltage slope and opposite in direction to the current flow in R 3 (i 7 in FIG. 8) which is proportional to the input voltage, it is possible to select the value of R 3 such that i 7 is equal to and just cancels i 8 during the R-C decay. Thus, the zero cancellation of the block 24 pole R B ·C B is performed by the action of the compensating resistor R 3 and the capacitor C 1 .
The system transfer function provides a sharp cut-off of high frequency noise by the three poles at f L , f L ' and f L ". Also, the system transfer function has a fairly sharp low frequency cut-off resulting from the two transmission zeros which remove low frequency noise and serve an even more important function which is to reject finger motion artifact. It is to be noted that succeptibility to finger motion is a primary limitation to the illustrated type of plethysmograph system. The pole-zero compensation although decreasing the sharpness of the low frequency cut-off, provides the equivalent of a two section low frequency filter which increases system signal-to-noise ratio beyond that obtainable with a three section filter and improves the overall system response to the heart blood pressure wave by eliminating certain overshoot components of the response which would be present in a system with three differentiators.
The improvement in system response can best be understood by referring also to the waveforms of FIG. 10 which shows an amplified and filtered heart pressure wave that reliably triggers the discriminator. A waveform 100 shows the reflectance signal resulting from the heart blood pressure modulation and a waveform 102 shows the heart blood pressure signal at the output of the block 24. The signal at the output of the amplifier A 4 with the pole zero cancellation of the resistor R 3 is shown by a waveform 104. The signal at the output of the amplifier A 5 is shown by a waveform 106 with the reference voltage level VR 4 and the trigger voltage level VR 5 at the discriminator 28. The pole zero cancellation deletes the effect of differentiation in the block 24 so that a heart blood pressure wave of the waveform 104 appears to be the result of a single differentiation of the photocurrent into the block 24 which was the original heart blood pressure amplitude modulation. A long time constant differentiation (R B C B ) in the block 24 is now replaced by a short time constant differentiation (R 1 ∥R 3 ·C 1 ) at the stage 86. After the second differentiation at the input of amplifier A 5 , the A 5 output being shown by the waveform 106, this second short time constant differentiation returns the voltage waveform rapidly to the amplifier A 5 quiescent output voltage which is VR 4 and therefore upon arrival of the next systolic pressure wave such as 107, the signal crosses the discriminator trip voltage threshold VR 5 with a fast or steep slope. The timing sensitivity to motion artifact is reduced by the steep slope of the leading edge of the systolic pulse 107 in comparison to a gradual slope which provides more sensitivity to motion artifact because the time position of the signal crossing the trigger voltage VR 5 is more severly modulated by motion artifact signals. Also, the second differentiation of the waveform 106 provides a highly predictable starting voltage by rapidly returning the A5 output to the baseline voltage (VR 4 ). It should be noted that at higher rates, the starting points will move closer to the back kick such as at 108 produced by the preceding pulse so that the systolic pulse starting voltage is displaced from the voltage VR 4 . However, at higher pulse rates, especially those produced by exercise, the heart rhythm generally becomes more uniform so that the displacement of the starting voltage displacement from VR 4 is uniform and has substantially no contribution on a beat-to-beat basis.
Laboratory investigations based on a four interval pulse average have shown that a 5-10 PPM (Pulses Per Minute) uncertainty can be expected with a single slow integration and differentiation arrangement and a 3-5 PPM uncertainty can be expected with an uncompensated triple differentiation of the illustrated system without the resistor R 3 . Tests have shown that with the two differentiator pole zero compensation of the preferred embodiment, only a 1-2 PPM uncertainty is to be expected.
In the illustrated system, it is desirable to have R B C B very large to decrease, at the amplifier A 4 , the ratio of DC gain to AC gain, that is (R 3 /R 1 ) should be a large ratio to insure wide DC operating margins. The time constants T H and T 3 must be equal, that is, R B C B must equal R 3 C 1 . In a hybrid circuit layout, such as in a watch, the size of the capacitor C B is limited. The value of R B is limited by the minimum allowable value of the low pass frequency f L , which if too small, will restrict the passage of desired high signal frequency components through the front end (block 24). The maximum value of the resistor R 3 is therefore constrained by two front end requirements as well as the limited maximum value of the capacitor C 1 . Thus, the long time constant in the block 24 is required to maintain proper system DC operating margins and the pole-zero cancellation provides improved dynamic characteristics in terms of pulse response and signal-to-noise performance.
Although particular embodiments of the invention have been described and illustrated herein, it is recognized that modifications and variations may readily occur to those skilled in the art and consequently, it is intended that the claims be interpreted to cover such modifications and equivalents. | A pulse IR reflectance plethysmograph system for heart rate measurement and display in a digital watch or as a medical instrument having a novel direct coupled pole zero cancellation circuit that compensates undesirable shaping effects on the heart blood pressure wave. The system utilizes a pulsed LED light emitting diode for transmitting light pulses and a photodiode for receiving light pulses reflecting from a finger. | 0 |
Background of the Invention
1. Field of the Invention
The present invention relates to a joint apparatus comprising standardized joint members for coupling standardized precut construction members so as to fabricate a frame work of a building or the like. Further, the present invention relates to a building construction comprising the joint apparatus and the precut members.
2. Discussion of Background Information
Conventional methods for construction of a building, are known, such as the frame work method and the built-up wall method.
The former method is called the "skeleton skin method" or the post & beam work method" and is a construction method using posts and beams as the main members.
The latter method is called "a two-by-four work method" or "a platform frame work method". According to this method, a building is constructed by attaching a wall member, which is formed by clamping a construction plywood or the like to a wall frame assembled by frame members, to a floor. The floor is bound by clamping a construction plywood or a surface member, having a performance comparable or superior to that of a construction plywood, to a floor frame assembled by sleepers.
The differences between these methods will now be described while comparing them with each other. In the first place, the space is constructed by "axes (lines)" in the former method and by "plates (faces)" in the latter method. The structure for imparting a rigidity to a floor surface, a wall surface and the like consists of "angle braces and diagonal braces" in the former method and "construction plywoods" in the latter method. The timbers used are "long timbers having a large section, mainly a square section (through posts)" in the former method and "short timbers having mainly a small section" in the latter method. The working process comprises "continuous fabrication of first floor and second floor axes, platforms and smnall chambers" in order in the former method and "a first floor platform, first floor walls, a second floor platform second floor walls and small chambers (stepwise operation)" in the latter method.
However, these conventional construction methods involve problems, as described below.
Namely, in the conventional frame work method, the space is mainly constructed by axes, and through posts are used. Accordingly, the operation requires much labor and the material cost is increased. Furthermore, since the structure imparting a rigidity to floor faces and wall faces is constructed by angle braces and diagonal braces, the structure becomes complicated and the operation requires time and labor. Especially, since a core wall structure is formed, a foundation should be made and the operation requires much more time and labor.
In the built-up wall method, the space is mainly constructed by faces, and angle braces or diagonal braces need not be used. However, this method is inferior to the frame work method in strength. Furthermore, the operation of assembling wall frames on a floor (operation platform) and raising up the assembled wall frame is necessary and this operation requires much time and labor.
In an operation of constructing a building such as a wooden house, after formation of a foundation, construction members such as timbers are skillfully cut and notched and they are skillfully assembled and coupled according to structure dynamics, and the main coupling portions of the construction members are secured by bolts or the like. In the conventional methods, however, a high degree of technique and skill are required for coupling the construction members, the operation efficiency is low, economical utilization of construction members is poor and the construction term is long. As a result, construction costs are increased.
In recently developed prefabricated buildings, the above-mentioned economical problems are tentatively solved by mass production, but the durability and strength, especially that of the coupled portions, are poor and diversity is insufficient. Furthermore, a prefabricated building becomes wretched with the lapse of time after construction and even if the prefabricated building is used for many years, calmness or massiveness is not imparted to the building.
Under this background, research has been performed by the present invention on coupling of construction members as described above, and, as the result, a joint for construction members, has been developed which is much simpler than the conventional combination of an iron plate and bolts and nuts, that is, the simplest coupling means heretofore adopted, and is superior in the strength to the utilization of wood cutting and notching means.
This joint is disclosed in U.S. Pat. No. 5,022,209.
This joint comprises a basic joint proper having a cubic or trapezoidal shape and a plate member extending outwardly from a surface of the basic joint proper in a plane substantially orthogonal to the surface, which is welded and secured to the basic joint proper, and a hole is formed through the plate member so that a fixing member such as a bolt can pass through this hole. According to this proposal, a variety of joint members can be obtained by combining the basic joint proper and the plate member while changing the shapes, numbers and directions thereof.
However, the basic joint propers that a have several problems including weight of the joint is considerably increased, the amount of material is increased and consequently the joint is disadvantageous from the economic viewpoint. Moreover, because weight of the joint is increased, the handling of the joint and the coupling operation of the construction members are difficult.
The man-hours for preparing the joint are increased and the production efficiency is lowered since the joint has many portions to be welded.
Further, a dimensional error is liable to occur since the basic joint proper is positioned between the construction members such as posts, the beams or the post and the beam. Therefore, some clearances between the construction members may be in error.
Conventionally, various kinds of joints for construction members have been proposed in addition to the joint mentioned above. However, none of these joints are suitable for a large sectional wooden building, such as architectures recently developing for a commercial use, e.g., an apartment building, a store building or an office building having three, four or five stories. Accordingly, most commercial architecture is constructed by means of a heavy steel member construction.
A building using heavy steel construction is disadvantageous from the economical viewpoint, and calmness or massiveness is not imparted to the building.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a joint apparatus for construction members which can effectively construct a building in which features of both of the conventional frame work method and the built-up wall method are selectively combined.
Another object of the present invention is to provide a joint apparatus for construction members which can reduce the dimensional error between posts, beams or the post and beam while reducing the weight of the joint apparatus, the quantity of the material and the construction cost, and improving the production efficiency of the joint apparatus.
A further object of the present invention is to provide a joint apparatus for construction especially suitable for a heavy sectional wooden building, such as a commercial architecture having three, four or five stories.
Still a further object of the present invention is to provide a building construction comprising the joint apparatus.
In accordance with the present invention, for attaining the foregoing objects, there is provided a joint apparatus for construction members adopted to couple with an end portion of at least one of construction members by means of clamping means wherein;
The construction member comprises at least one of a longitudinal construction member and a lateral construction members, both of which are made of timber. The longitudinal construction members comprising at least one of a first longitudinal construction member having a first groove of an approximate cross-figured lateral sectional shape formed at an end portion of the first longitudinal construction member and a second longitudinal construction member having a second groove of an approximate straight line-figured lateral sectional shape at an end portion of the second longitudinal construction member and a third longitudinal construction member having a third groove of an approximate cross-figured lateral sectional shape formed at an end portion of the third longitudinal construction member and the lateral construction member having a fourth groove of an approximate straight line-figured lateral sectional shape at an end portion of the lateral construction member and the clamping means comprises first to fourth clamping means comprising bolt-nut assemblies,
the joint apparatus comprising;
a basic joint member and
at least one member selected from a first application joint member, a second application joint member and a third application joint member,
the basic joint member comprising first to fourth connecting plate portions defining a first fitting protrusion having an approximate cross-figured lateral sectional shape to be fitted with the corresponding first groove of the first longitudinal construction member and also with the corresponding fourth groove of the lateral construction member at at least an end portion of the first to fourth connecting plate portions,
the basic joint member including at least a pair of the connecting plate portions opposed to each other, including first to fourth connecting plate portions, first insertion holes through which the first clamping means penetrate for coupling the connecting plate with the end portion of the first longitudinal construction member, so that the first fitting protrusion is fitted with the corresponding first groove of the first longitudinal construction member, and second insertion holes through which the second clamping means penetrate for coupling the connecting plate with the end portion of the lateral construction member so that the ends of the pair of connecting plate portions are fitted with the fourth groove of the lateral construction members respectively,
the first application joint member comprising an end plate portion fixed to at least one of the top and bottom end faces of the first to fourth connecting plate portions of the basic joint member and extending in a lateral direction so as to receive the end portion of one of the first to third longitudinal construction members,
the second application joint member comprising a fifth connecting plate portion fixed to an upper face of the first application joint member, the fifth connecting plate portion upwardly extending in parallel with a pair of the connecting plate portions opposed each other of the first to fourth connecting plate portions and having third insertion holes through which the third clamping means penetrate for coupling the fifth connecting plate portion with the end portion of the second longitudinal construction member so that the fifth connecting plate portion is fitted with the corresponding second groove of the second longitudinal construction member, and
the third application joint member comprising the first application joint member and the sixth to ninth connecting plate portions defining a second fitting protrusion having an approximate cross-figured lateral sectional shape to be fitted with the corresponding third groove of the third longitudinal construction member, the sixth to ninth connecting plate portions being fixed to the upper face of the first application joint member and upwardly extending in parallel with the first to fourth connecting plate portions respectively,
the third application joint member being formed, in at least a pair of the connecting plate portions opposed to each other of the sixth to ninth connecting plate portions, fourth insertion holes through which the fourth clamping means penetrate for coupling the end portion of the third longitudinal construction member so that ends of the pair of connecting plate portions of the sixth to ninth connecting plate portions are fitted with the third grooves of the third longitudinal construction members.
According to the present invention, for example, a post as the longitudinal construction member and a groundsills as the lateral construction member are set, respectively, to the joint apparatus so that the first fitting protrusion of the basic joint member is fitted to the corresponding first groove of the approximate cross-figured lateral sectional shape formed at the end portion of the post as the longitudinal construction member and the end portions of the first and third connecting plate portions are fitted, respectively, to the corresponding first grooves of the approximate straight line-figured lateral sectional shapes formed at the end portions of the groundsills, and clamped by using clamping means through corresponding insertion holes.
In this case, the end face of the post is received by the end plate portion of the first application joint apparatus. The end faces of the groundsills are received by the side faces of the posts, and accordingly, the side faces of the post are in closely contact with the end faces of the groundsills.
Further, for example, the posts and the beams are set, respectively, to the joint apparatus so that the first fitting protrusion of the basic joint member and the second fitting protrusion of the third application joint member are fitted to the corresponding first and third grooves of the approximate cross-figured lateral sectional shapes formed, respectively, at the end portions of the upper and lower posts as first and third longitudinal construction members, and the end portions of the first and third connecting plate portions are fitted to the corresponding fourth grooves of the approximate straight line-figured lateral sectional shapes formed, respectively, at the end portions of the beams, and clamped by using clamping means through corresponding insertion holes.
In this case, the end faces of the upper and lower posts are received by the end plate portion, respectively. Further, the end faces of the beams are received by the side faces of the post. Accordingly, the side faces of the lower post are in closely contact with the end faces of the beams and the end faces of the beams are received by the end plate portion.
For coupling an upper post as a second longitudinal construction member, the second application joint member is also used.
Since a joint member having a fitting protrusion of a cross-figured lateral sectional shape is used as the basic joint member, the weight of the joint apparatus and the quantity of the material can be reduced, and therefore, the construction cost can be reduced. Further, because the weight of the joint apparatus is reduced, the handling of the joint can be simplified and the operation of connecting the construction members is facilitated.
The man-hours for preparing the joint is reduced and the production efficiency can be improved since the joint has only a few portions to be welded.
A dimension error can be avoided since the construction members, such as the posts, the beams, the post and the beams and the like, are in closely contact with each other.
Since a joint member having a fitting protrusion of a cross-figured lateral sectional shape is used as the basic joint member, longitudinal and lateral construction members, namely, longitudinal posts, lateral beams and the like, can be variably clamped to the basic joint member. Further, the clamping of the construction members can be accomplished irrespective of the direction thereof. Therefore, the member of items of the joint can be reduced, the production efficiency can be improved and the construction cost can be reduced.
It is preferable that the basic joint member may comprise a single plate member integrally defining two connecting plate portions opposed each other and two plate members which define, respectively, two connecting plate portions opposed each other and are fixed to each side surface of the single plate member at each end portion of the two plate members. The two plate members may extend orthogonally to the respective side surfaces of the single plate member.
The end plate portion of the first application joint member may be connected to the bottom end faces of the first to fourth connecting plate portions of the basic joint member at an upper face of the end plate, and may extend orthogonally to the first to fourth connecting plate portions.
The end plate portion has approximately the same size as the lateral section of the end portion of the first longitudinal construction member.
The end plate portions of the first application joint member may be connected to the bottom end face of an outer end portions of at least one of the connecting plate portions of the basic joint member and extend approximately orthogonally to the connecting plate portion.
The end plate portion of the first application joint member may be connected to the top end faces of the first to fourth connecting plate portions of the first fitting protrusion at lower face of the end plate, and extend orthogonally to the first to fourth connecting plate portions.
The end plate portion may have approximately the same size as the lateral section of the first longitudinal construction member.
The fifth insertion holes may be formed in the end plate portion of the first application joint member through which anchor bolt means penetrate to couple the end plate portion with a foundation.
The second fitting protrusion may comprise a single plate member integrally defining two connecting plate portions opposed each other and two plate members defining, respectively, two connecting plate portions opposed each other and being fixed to each side surface of the single plate member at each end portion of the two plate members, the two plate members extending orthogonally to the respective side surface of the single plate member.
In accordance with the present invention, there is also provided a building construction constructed by coupling the joint apparatus for construction members, in combination with clamping means, which comprises the basic joint member combined with at least one member selected from the first application joint member, the second application joint member and the third application joint member, with at least one member selected from the first longitudinal construction member, the second longitudinal construction member, the third longitudinal construction member and the lateral construction members.
Embodiments according to the present invention will now be described in detail with reference to the accompanying drawings. The structure and features of the present invention shall be fully understood by the embodiments. However, the present invention is not limited to the embodiments and can be modified within the range of the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view illustrating one embodiment of a joint apparatus for construction members according to the present invention.
FIGS. 2A, 2B and 2C show a plan view, a front view and a side view of the joint apparatus in FIG. 1, respectively.
FIG. 3 is a front view showing an example in which the joint apparatus in FIG. 1 is used.
FIGS. 4A through 4E are perspective views showing modifications of the joint apparatus shown in FIG. 1.
FIG. 5 is a perspective view illustrating another embodiment of the joint apparatus for construction members according to the present invention.
FIGS. 6A, 6B and 6C show a plan view, a front view and a side view of the joint apparatus in FIG. 5, respectively.
FIG. 7 is a front view showing an example in which the joint apparatus in FIG. 5 is used.
FIGS. 8A through 8C are perspective views showing modifications of the joint apparatus in FIG. 5.
FIG. 9 is a perspective view illustrating a further embodiment of the joint apparatus for construction members according to the present invention.
FIG. 10 is a perspective view illustrating a still further embodiment of the joint apparatus for construction members according to the present invention.
FIGS. 11A, 11B and 11C show a plan view, a front view and a side view of the joint apparatus in FIG. 10, respectively.
FIG. 12 is a front view showing an example in which the joint apparatus in FIG. 10 is used.
FIGS. 13A through 13D are perspective views showing modifications of the joint apparatus in FIG. 10.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
As one embodiment of a joint apparatus (to be referred as a connector hereinafter) according to the present invention, a pedestal connector 1 for coupling a groundsill with a post or the like is shown in FIGS. 1 to 3.
Namely, a pedestal fitting 2 acting as a basic joint member comprises a first fitting protrusion 2A having an approximate cross-figured lateral sectional shape which is fitted to a corresponding groove having an approximate cross-figured lateral sectional shape formed in an end portion of a post 11.
The first fitting protrusion 2A comprises first to forth connecting plate portions 3 to 6 orthogonally fixed to each other at one end of each connecting plate portion and extending in a longitudinal direction.
The lateral total length of the first and third connecting plate portions 3 and 5 opposed to each other is longer than the lateral total length of the second and fourth connecting plate portions 4 and 6 opposed to each other.
In this case, for instance, the basic joint member is formed in such a manner that two plate members defining the second and fourth connecting plate portions 4 and 6, respectively, are fixed by welding to a single plate member integrally defining the first connecting plate portion 3 and the third connecting plate portion 5.
Insertion holes 7 for insertion of bolts of bolt-nut assemblies as the clamping means for coupling post 11 are formed in the second and fourth connecting plate portions 4 and 6. Insertion holes 7 for insertion of bolts of bolt-nut assemblies as the clamping means for coupling the post 11 and insertion holes 8 for insertion of bolts for coupling groundsills 12 acting as lateral construction members are formed in the first and third connecting plate portions 3 and 5 which are opposed to each other.
A first application joint member, that is, an end plate portion 9 as a clamping portion to a foundation or the like in the present embodiment, extends orthogonally to the respective surfaces of the connecting plate portions 3 through 6, and is connected by welding to the bottom end face of the first fitting protrusion 2A at an upper face thereof.
Insertion holes 10 for insertion of anchor bolts embedded in the foundation or the like are formed in the end plate portion 9.
the size of the end plate portion 9 is same as the lateral section of the end portion of the post 11.
As shown in FIG. 3, clamping of the post 11 and the groundsills 12 to the pedestal connector 1 is accomplished, for example, by setting the post 11 and the groundsills 12 at the pedestal connector 1, respectively, so that the first fitting protrusion 2A is fitted to the corresponding groove of the approximate cross-figured lateral sectional shape formed in advance by cutting at the end portion of the post 11, and end portions of the first and third connecting plate portions 3 and 5 are fitted, respectively, to corresponding grooves, each of which has an approximate straight line-figured lateral sectional shape, formed in advance by cutting at the end portions of the groundsills 12, and clamping them by using bolts and nuts.
In this case, the lower end face of the post 11 is received by the end plate portion 9. Further, the end faces of the groundsills 12 are received by the side faces of the post 11 and the side faces of the post 11 are in closely contact with the end faces of the groundsills 12.
Numeral 13 in FIG. 3 shows construction plywood to be fixed to the top end faces of the groundsills 12.
A laminated wood is used for the post 11. The laminated wood is formed by combining wooden plates so that the fabric directions of the wooden plates are parallel to the longitudinal direction of the post 11 and adhering them with synthetic resin adhesive.
Modifications of the pedestal connector 1 are shown in FIGS. 4A through 4E.
The pedestal connector in each view comprises the basic joint member combined with the first application joint member, namely, the pedestal fitting combined with the end plate portion. The lateral length of the first to fourth connecting plate portions in the pedestal fitting can be changed to various sizes.
In another embodiment of the beam-girth connector 14, according to the present invention, shown in FIGS. 5 to 7, a beam-girth connector 14 couples upper and lower posts with each other, girths as lateral construction members with each other and in addition, floor beams with each other.
As in the pedestal fitting in the aforementioned embodiment, a first post-connecting fitting 15, acting as a basic joint member, comprises a first fitting protrusion 15A. Insertion holes 20 for insertion of bols as clamping means, for coupling a post 29 are formed in first to fourth connecting plate portions 16 to 19 defining the first fitting protrusion 15A. Insertion holes 21, for insertion of bolts for coupling beams 31 as lateral construction members, are formed in the first and third connecting plate portions 16 and 18.
First application joint members, namely, end plate portions 22, receiving the beams 31 in this embodiment, extend orthogonally to the respective surfaces of the first and third connecting plate portions 16 and 18, and are fixed by welding to the bottom end faces of the lower side of end portions of the respective connecting plate portions 16 and 18.
Additionally, the space between both of the end plate portions 22 is approximately the same dimension as the width of the lateral section of the post 29.
Further, an end plate portion 23 receiving a bottom end face of an upper post 30 and a top end face of the lower post 29, as a first application joint member, extends orthogonally to the respective surfaces of the connecting plate portions 16 to 19 and is fixed to the top end face of the first fitting protrusion 15A of the first post-connecting fitting 15.
The dimension of the end plate portion 23 is approximately the same as the lateral section of the end portion of the post 30.
A second post-connecting fitting 24 for connecting the upper post 30, as a third application joint member, comprises a second fitting protrusion 24A having an approximate cross-figured lateral sectional shape. The second fitting protrusion 24A comprises sixth to ninth connecting plate portions 25 to 28, orthogonally fixed to each other at each end portion thereof, and extending in parallel with the connecting plate portions 16-19.
A bottom end face of the second fitting protrusion 24A is fixed by welding to the top end face of the end plate portion 23.
The lateral length of the connecting plate portions 25 to 28 is identical with each other and is approximately the same as the width of the lateral section of of post 30.
In this case, for instance the second fitting protrusion 24A is formed in such a manner the two plate members defining the seventh and ninth connecting plate portions 26 and 28, respectively opposed to each other, are fixed by welding to each side of a single plate member which integrally defines the sixth connecting plate portion 25 and the eigth connecting plate portion 27 opposed to each other.
Insertion holes 33 for insertion of bolts as clamping means for coupling the post 30, are formed in the sixth to ninth connecting plate portions of the second fitting protrusion 24A.
As shown in FIG. 7, clamping of the posts 29 and 30, and the beams 31 to the beam-girth connector 14 is accomplished, for example, by setting the posts 29 and 30, and the beams 31 at the beam-girth connector 14, respectively, so that the first fitting protrusion 15A of the first post-connecting fitting 15 and the second fitting protrusion 24A of the second post-connecting fitting 24 are fitted, respectively, to corresponding grooves, each of which has an approximate cross-figured lateral sectional shape, formed in advnace by cutting at the end portions of the lower and upper post 29 and 30. The end portions of the first and third connecting plate portions 16 and 18 are fitted, respectively, to corresponding grooves, each of which as an approximate straight line-figured lateral sectional shape, formed in advance by cutting at the end portions of the beams 31, and clamping them by using bolts and nuts.
In this case, the end faces of the posts 29 and 30 are received by the end plate portion 23, respectively. Further, the end faces of the beams 31 are received by the side faces of the lower post 29, the side faces of the lowr post 29 are in close contact with the end faces of the beams 31, and the end faces of the beams 31 are received by the end plate portions 22, respectively.
Numeral 32 in FIG. 7 shows construction plywood to be fixed to the top end portions of the beam 31.
A laminated wood is used for the posts 29 and 30, and for the beams 31.
Modifications of the beam-girth connector 14 are shown in FIGS. 8A to 8C.
The beam-girth connector in each view comprises the basic joint member combined with the first application joint member and the third application joint member, namely, the first-post connecting fitting, combined with the end plate portions and the second post-connecting fitting. The lateral length of the first to fourth connecting plate portions in the first post-connecting fitting can be changed to various sizes.
FIG. 9 shows a further embodiment of the beam-girth connector.
A beam-girth connector 34 in this embodiment has a second post-connecting fitting 35 for connecting an upper post as a second application joint member instead of the third application joint member in the aforementioned embodiment. The second post-connecting fitting 35 comprises a fifth connecting plate portion 36 extending in a longitudinal direction parallel to the opposed connecting plate portion.
Insertion holes 37 for insertion of bolts, as clamping means for coupling a post, are formed in the fifth connecting plate portion 36 so that the fifth connecting plate portion is fitted into the corresponding straight lines-figured lateral sectional shape which is formed at the end portions of the post 30.
As a still further embodiment of the connector according to the present invention, FIGS. 10 to 12 show a capital connector 38 to be used for a capital.
Namely, in the capital connector 38, an end plate portion 40 receiving the top end portion pf a post 39, as a first application joint member, extends orthogonally to the respective surfaces of the connecting plate portions 16 to 19 and is fixed by welding to the top end face of the fitting protrusion 15A of the first post-connecing fitting 15 in FIG. 5. The end platte portion 40 does not comprise second and third application joint members.
Modifications of the capitall connector are shown in FIGS. 13A to 13D.
The capital connector in each view comprises the basic joint member combined with the first application joint member, namely, the first post-connecting fitting combined with the end plate portions. The lateral length of the first to fourth connecting plate portions can be changed to various sizes.
Incidentally,the thickness of a plate member defining each connector mentioned above, for example, is set to 4.5 mm, however, the thickness can be set to an optimum thickness according to a span of the like.
As is apparent from the description mentioned above, according to the joint apparatus for construction members and the building construction of the present invention, coupling and connection of the construction members can be completed only by a simple operation using clamping means such as bolt clamping. The floor space and height can be freely changed by using minimum standard buildings, and if appropriate joint apparatus are used, the floor space and height can be very easily changed in anticipation of enlargement or remodeling. A variety of houses meeting the demands of users can be constructed by using a small number of standard buildings, similar to the case where various toy blocks differing in the shape are combined. Moreover, since the joint apparatus and the construction members connected by the joint apparatus can be standardized, it is sufficient if all the joint apparatus are prepared in a factory and only the construction members are precut in the factory. Still further, the connection of construction members attained by the joint apparatus is very strong and the strength is much higher than the strength attained in the conventional methods using iron plates, bolts and nuts.
The prominent characteristic features of the joint apparatus of the present invention are as follows.
Since a joint member having a simple cross-figured shape is used as the basic joint member, instead of the conventional joint proper having a cubic or trapezoidal shape, the weight of the joint apparatus and the quantity of the material can be reduced, and therefore, the construction cost can be reduced. Further, as a result that the weight for the joint apparatus is reduced, the handling of the joint can be simplified and the operation of connecting the construction members can be facilitated.
The man-hours for preparing the joint are reduced and the production efficiency can be improved since the joint has only a few portions to be welded.
Further, a dimension error can be avoided since the construction members, such as the posts, the beams, the post and beams, and the like, are in close contact with each other.
Since a joint member having a cross-figure shape is used as the basic joint member, longitudinal and lateral construction members namely, longitudinal posts, lateral beams and the like, can be variably coupoled to the basic joint member and further, the clamping of the construction members can be accomplished irrespective of the directions thereof. Therefore, items of the joint can be reduced, the production efficiency can be improved and the construction cost can be reduced.
Incidentally, according to the present invention, a frame work can be formed at about 1/3 cost in comparison with a heavy steel construction of the same scale, and therefore, the construction cost can be reduced.
Particularly, advantages mentioned below are obtained by the building construction according to the present invention.
Namely, the joint apparatus of the present invention is used for a large span construction and laminated woods are used as the construction members, such as the beams, the posts and the like. Therefore, a warp or a shrinkage of the construction members can be avoided. Further, since the building construction can be divided by large grids, the working operation can be improved. Moreover, the working operation can be standardized and therefore, performed irrespective of the skill of the worker. Accordingly, the building construction according to the present invention has a remarkable effect on the working operation of a heavy section wooden building, such as a commercial architecture (an apartment building, a store building of an office building) of three, four or five stories.
Calmness or massiveness can be imparted to this heavy section wooden building in comparison with the building made of the heavy steel construction. | Joint apparatus for construction members and a building construction are provided with standardized joint members including at least one of a basic joint member including a fitting protrusion of an approximately cross-figured lateral sectional shape, an end plate portion connected at a top or a bottom face of the fitting protrusion, and a projection extending upwardly from the end plate portion for fitting a groove of approximate straight line or cross-figured lateral sectional shape. The joint apparatus is suitable for coupling standardized precut timbers capable of use for construction members so as to form a framework of a building. The joint apparatus for construction members can effectively construct a building in which characteristics of both the conventional frame work method and the built-up wall method are mixed together. | 4 |
BACKGROUND
The invention pertains to spun-dyed aramid fibers.
Spun-dyed aramid fibers are known. EP 0 356 579 A describes spun-dyed p-aramid fibers containing 0.01 to 6% by weight of a completely organic pigment selected from the groups of (1) monoazo and diazo pigments, (2) anthanthrone pigments, (3) indanthrone pigments, (4) pyranthrone pigments, (5) vilanthrone pigments, (6) flavanthrone pigments, (7) quinacridone pigments, (8) dioxazine pigments, (9) indigoid and thioindigoid pigments and (10) isoindolinone pigments. Though said spun-dyed fibers exhibit a good maintenance of their colouristic properties, customers always desire further spun-dyed aramid fibers, which—as possible—exhibit a better fastness of colouristic properties of spun-dyed aramid fibers, especially under humid conditions of use and during washing.
Therefore, the problem of the present invention is to provide further spun-dyed aramid fibers with at least the same or better fastness of colouristic properties.
SUMMARY
Said problem is solved by spun-dyed aramid fibers, wherein spun-dyeing was performed with a completely organic pigment, characterized in that the pigment exhibits the chemical structure of formula (I),
wherein independently from one another
R 1 represents a substituent of formula X a or a substituent of formula X b
wherein X a is linked via the group NH on the left hand side of the triazine ring,
whilst X b is linked via the carbon atom, which is in a para relationship with the NH 2 -group, and R 2 represents H or NH 2 .
Surprisingly, the inventive spun-dyed aramid fibers exhibit a fastness of colouristic properties, especially under humid conditions of use and during washing, which at least equals that of the spun-dyed aramid fibers of the prior art. In preferred embodiments the spun-dyed aramid fibers of the present invention exhibit an even better fastness of colouristic properties than the spun-dyed aramid fibers of the prior art.
DETAILED DESCRIPTION OF EMBODIMENTS
Within the scope of the present invention the term “completely organic pigment” means a pigment, the chemical structure of which does not contain any metal or any metal ion.
In a preferred embodiment of the spun-dyed aramid fibers of the present invention R 1 represents the substituent X a
and R 2 represents H, so that the pigment is 1,1′-[(6-Phenyl-1,3,5-triazine-2,4-diyl)diimino]bisanthraquinone (C.I. Pigment Yellow 147), which can be obtained from CIBA-Geigy (BE) under the designation Filester Yellow RNB.
In a further preferred embodiment of the spun-dyed aramid fibers of the present invention R 1 represents the substituent X b
and R 2 represents NH 2 , so that the pigment is 1,1′-Diamino-4-4′-dianthraquinonyl (C.I. Pigment Red 177), which can be obtained from Clariant International Ltd. (CH) under the designation Hostaperm Red M2B.
In a further preferred embodiment of the spun-dyed aramid fibers of the present invention the pigment is a mixture of a first weight part consisting of C.I. Pigment Yellow 147 and a second weight part consisting of C.I. Pigment Red 177, wherein said first and second weight parts add to 100 wt. % of the pigment contained in the spun-dyed aramid fibers of the present invention. Depending on the chosen values for the first and second weight part spun-dyed aramid fibers with different orange colours can be provided.
The weight percentage of the pigment of formula (I) based on the weight of the spun-dyed aramid fibers of the present invention can be chosen depending of the desired colouristic effect and preferably ranges from 0.1 weight % to 6 weight %, even more preferred from 0.5 weight % to 4 weight %.
Within the scope of the present invention the term “spun-dyed aramid fibers” means filaments or filament yarns, consisting of an aromatic polyamide as the fiber forming polymer, i.e. of a copolymer, wherein at least 85% of the amide (—CO—NH—) bonds are directly bonded with two aromatic rings.
P-aramid fibers, especially poly(p-phenylene terephthalamide) fibers are preferred as the aramid fibers in the present invention and can be obtained under the trade name TWARON by Teijin Aramid GmbH (DE). The fiber-forming polymer of poly(p-phenylene terephthalamide) fibers is a polymer obtained by the mol:mol polymerization of p-phenylene diamine and terephthalic acid dichloride. Furthermore, as the fiber-forming polymer for the purposes of the present invention aromatic copolymers are suited as well, wherein p-phenylene diamine and/or terephthalic acid are substituted partly or completely by other aromatic diamines and/or dicarboxylic acids.
The favourable properties of the spun-dyed aramid fiber of the present invention qualify said fiber to be used in all kind of applications, in which aramid-fibers can be used.
For example the spun-dyed aramid fibers of the present invention can be used to manufacture crimped and cut fibers. The crimped and cut fibers can be used mainly for manufacturing textile fabrics, which can be a woven, nonwoven, knitted, crocheted or braided textile fabrics. Furthermore, the spun dyed fibers of the present invention can be used for manufacturing textile fabrics directly, without crimping and cutting them.
The spun dyed aramid fibers of the present invention can also be converted into pulp.
Furthermore, the spun-dyed aramid fibers of the present invention can be used together with a matrix resin or without a matrix resin to manufacture a composite.
Still another attractive use of the spun-dyed aramid fibers of the present invention is to manufacture a rip-cord for optical cables. A rip-cord is a constituent of the core protection of optical fibers in an optical cable. The rip cord is generally used to split open the outer shell of the cable.
Aramid fibers spun-dyed especially with triazine C.I. Pigment Yellow 147, i.e. with 1,1′-[(6-Phenyl-1,3,5-triazine-2,4-diyl)diimino]bisanthraquinone can be manufactured by a process comprising the steps
a) preparing a mixture of (C.I. Pigment Yellow 147)-powder with a sandy spin dope consisting of poly(p-phenylene terephthalamide) and concentrated sulphuric acid which contains at least 80 weight % H 2 SO 4 ,
wherein said mixture preferably exhibits
a concentration of C.I. Pigment Yellow 147 in the range from 0.07 weight % to 1.2 weight % and a concentration of poly(p-phenylene terephthalamide) in the range from 14 weight % to 20 weight %,
b) transporting the mixture into a single or double screw extruder, or into a single or double shaft kneader, c) heating the mixture in the melt extruder to a temperature in the range of 70° C. to 95° C., most preferably to 85° C., d) spinning the heated mixture through an orifice into an air gap and then into a coagulation bath consisting of water or aqueous sulphuric acid to coagulate the mixture into coagulated fibers, e) washing the coagulated fibers with water and/or diluted alkali, f) drying the washed fibers and g) winding the dried fiber.
In step a) of the above process the mixture of the pigment with the sandy spin dope can be prepared either by
dispersing the pigment powder in the concentrated sulphuric acid and dosing the (pigment/concentrated sulphuric acid)-dispersion to the molten aramid spin dope or adding the pigment powder to the solid or molten aramid spin dope.
As mentioned before, surprisingly the spun-dyed aramid fibers of the present invention exhibit a fastness of colouristic properties, especially under humid conditions of use and during washing, which at least equals that of the spun-dyed aramid fibers of the prior art. Without the wish to be bound to a particular theory one reason for said high degree of maintenance of the colouristic properties might be the surprisingly high stability of pigments of formula (I) against sulfonation under conditions of solvent and temperature similar to the conditions in the aramid spin dope. The inventors measured 1 H NMR-spectra of C.I. Pigment Yellow 147 and of C.I. Pigment Red 177. For this purpose 20 mg of the corresponding pigment was dissolved in 98 weight % D 2 SO 4 just before measuring. The solution was inserted into a ceramic spinner and the spinner was inserted into an NMR apparatus (Bruker Advance III 400 MHz NMR spectrometer) set at 80° C. 1 H NMR-spectra were measured in time intervals of 5 minutes.
FIG. 1 shows the obtained 1 H NMR-spectra of C.I. Pigment Yellow 147 after 5 minutes and after 1 hour. FIG. 1 also shows the formula of C.I. Pigment Yellow 147 together with figures ranging from 1 to 4 and 8 to 13 which mark the positions of carbon-hydrogen bonds in the pigment, wherein the hydrogen atom (H; not shown in FIG. 1 ) could be substituted by a sulfonic acid group (SO 3 H). The 1 H NMR peaks originated by said H atoms are also identified in the obtained spectra. FIG. 1 shows, that the peaks of all of the H atoms after 1 hour in the 80° C. D 2 SO 4 are completely identical with the peaks after 5 minutes. So, surprisingly not any sulfonation occurred in C.I. Pigment Yellow 147.
FIG. 2 shows the obtained 1 H NMR-spectra of C.I. Pigment Red 177 after 5 minutes and after 2 hours. FIG. 2 also shows the formula of C.I. Pigment Red 177 together with figures ranging from 1 to 6 which mark the positions of carbon-hydrogen bonds in the pigment, wherein the hydrogen atom (H; not shown in FIG. 2 ) could be substituted by a sulfonic acid group (SO 3 H). The 1 H NMR peaks originated by said H atoms are also identified in the obtained spectra. FIG. 2 shows, that the peaks of all of the H atoms after 2 hours in the 80° C. D 2 SO 4 are completely identical with the peaks after 5 minutes. So, surprisingly not any sulfonation occurred in C.I. Pigment Red 177.
The surprisingly high resistance of pigments of formula (I) against highly concentrated sulfuric acid is also beneficial for the spinning process to obtain the spun-dyed aramid fibers according to the present invention, because said pigments are not chemically modified in the presence of the highly concentrated sulfuric acid which is used for preparing and spinning the aramid spin-dope containing said pigments.
Furthermore, it was found that pigments of formula (I) exhibit a surprisingly high stability under alkaline conditions, even under high concentrations of alkali. Therefore, the spun-dyed aramid fibers according to the present invention pass the alkaline neutralization step (e) of the process described above without being chemically modified. And the spun-dyed aramid fibers according to the present invention pass alkaline laundering conditions without being chemically modified.
EXAMPLES
The invention is explained in more detail in the following examples.
Example 1
i) Preparation of a Sandy Spin Dope and of a Pigment Pre-Mix
A sandy spin dope was prepared consisting of 19.85 wt. % poly(p-phenylene terephthalamide) (PPTA) in concentrated sulphuric acid, i.e. in 99.8 wt. % H 2 SO 4 . The PPTA had a relative viscosity η rel =4.8-5.2. η rel was measured in a solution of 0.025 g/ml PPTA in 96 wt. % H 2 SO 4 at 25° C.
The following three pigments
C.I. Pigment Yellow 147, i.e. with 1,1′-[(6-Phenyl-1,3,5-triazine-2,4-diyl)diimino]bisanthraquinone, C.I. Pigment Red 122, i.e. with 5,12-Dihydro-2,9-dimethylquino[2,3-b]acridine-7,14-dione, and C.I. Pigment Blue 15, i.e. with (29H,31H-phthalocyaninato(2-)-N29,N30,N31,N32)copper.
were mixed in a (1:1:1)-weight ratio in 99.8 wt. % H 2 SO 4 resulting in a pigment pre-mix, wherein the total amount of pigment in H 2 SO 4 was 20 wt. %.
C.I. Pigment Red 122 and C.I. Pigment Blue 15 were added in order to obtain spun-dyed PPTA-fibers having incorporated an internal colouristic red standard and an internal colouristic blue standard needed to evaluate the colouristic properties of the spun-dyed PPTA fibers in a (L*a*b*)-measuring device described in v). C.I. Pigment Red 122 and C.I. Pigment Blue 15 can be used as internal colouristic standards for red and blue, respectively, because it was found, that both the colour of C.I. Pigment Red 122 and the colour of C.I. Pigment Blue 15 do not change in colouristic properties during spinning and washing.
ii) Preparation of a Coloured Sandy Spin Dope
The pigment pre-mix and the sandy spin dope were both fed separately and continuously to a single shaft kneader, heated in the single shaft kneader at a temperature in the range of 80-85° C. resulting in a coloured sandy spin dope, which additionally to the PPTA and the concentrated sulphuric acid consisted of 0.4 wt. % C.I. Pigment Yellow 147, 0.4 wt. % C.I. Pigment Red 122, and 0.4 wt. % C.I. Pigment Blue 15. As indicated by the systematic names of C.I. Pigment Red 122 and of C.I. Pigment Blue 15 both of said pigments do not fall under formula (I).
iii) Spinning of the Dope
The coloured sandy spin dope obtained from ii) was spun through an orifice into an air gap and then into a coagulation bath consisting of aqueous sulphuric acid (10 wt. %) to obtain coagulated fibers. The coagulated fibers were washed with water and diluted alkali. The washed fibers were dried and wound resulting in a spun-dyed PPTA multifilament yarn (yarn titer: 3360 dtex, 2000 individual filaments) containing
2 wt. % C.I. Pigment Yellow 147,
2 wt. % C.I. Pigment Red 122, and
2 wt. % C.I. Pigment Blue 15.
iv) Washing of the Spun-Dyed Multifilament Yarn
8 grams of the spun-dyed multifilament yarn obtained in iii) were washed five times in a washing machine (Miele WS5436 using washing program A). In each of the five washings 20 grams of a regular washing powder (brand ‘All classic professional’, ex. Unilever) were used and a washing temperature of 95° C. was applied.
v) Colouristic Characterization of the Spun-Dyed Fibers
In order to determine the washing fastness, the spun-dyed fibers were characterized before and after the five times washing described in iv) by an (L*a*b*)—measurement using a Minolta CM3600-D Spectrophotometer.
In order to diminish the influence of the glare and fibrillation effects of the spun-dyed fibers on the results of the (L*a*b*)-measurement not the spun-dyed fibers were used for the (L*a*b*)-measurement, but tablets, which were obtained from the spun-dyed fibers by grinding and pressing as described in the following.
A 1 st sample of the spun-dyed multifilament yarn obtained from iii) was grinded in a Herzog HMS 100 grinding mill and cold pressed to a 1 st tablet with a Fontijn TP400 press. In the same manner a 2 nd sample of the spun-dyed multifilament yarn obtained from iii) was transformed into a 2 nd tablet. The resulting values for L*, a* and b* of the 1 st and 2 nd tablet were arithmetically averaged. The resulting averages of L*, a* and b* represent the colouristic properties of the spun-dyed fibers before washing.
Analogously the same procedure was performed with washed spun-dyed fibers obtained from iv). The resulting averages L*, a* and b* represent the colouristic properties of the spun-dyed fibers after washing.
The differences of the corresponding averages before and after washing were used to quantify the colouristic stability of the spun-dyed fibers in terms of Δb* and ΔE ab* as described in the following.
As mentioned before, the colouristic properties both of C.I. Pigment Red 122 and C.I. Pigment Blue 15 doe not change during spinning and washing. Therefore, colouristic differences of the spun-dyed fibers after the five time washing are purely caused by the applied yellow pigment, i.e. in this example by C.I. Pigment Yellow 147.
With respect to C.I. Pigment Yellow 147 especially the shift of the b*-value, Δb*=(b* 2 −b* 1 ), is of interest. This is, because Δb* quantifies the (yellow to blue)-shift in the (L*a*b*)-diagram caused by the five washings. Therefore, Δb* quantifies the degree of colouristic stability of C.I. Pigment Yellow 147 in the spun-dyed fibers: The lower Δb* the higher is the colouristic stability of the yellow pigment, i.e. in this example of C.I. Pigment Yellow 147, in the PPTA-fibers.
A further parameter to quantify the colouristic stability of C.I. Pigment Yellow 147 in the PPTA-fibers, is the total colour change ΔE ab* , which was determined from the formula
Δ E ab* =[( L* 2 −L* 1 ) 2 +( a* 2 −a 1 ) 2 +( b* 2 −b* 1 ) 2 ] 1/2 ,
wherein L*, a* and b* are the measured values in the (L*a*b*)-coordinate system, and wherein
L* is the lightness component in the (L*a*b*)-diagram, a* is the red component in the (L*a*b*)-diagram, b* is the yellow component in the (L*a*b*)-diagram, index 1 denotes before washing, and index 2 denotes after five times washing.
The lower ΔE ab* the higher is the colouristic stability of the applied yellow pigment, i.e. in this example of C.I. Pigment Yellow 147, in the PPTA-fibers.
In the table below ΔE ab* , and Δb* are shown.
Comparative Example 1
Comparative example 1 was performed as example 1 with the only difference that instead of the C.I. Pigment Yellow 147 C.I. Pigment Yellow 110 was used.
C.I. Pigment Yellow 110 is Bis(4,5,6,7-Tetrachloro-3-oxoisoindolin-1-ylidene)-1,4-phenylenediamine and therefore, does not fall under formula (I).
The resulting spun-dyed PPTA multifilament yarn contained 2 wt. % C.I. Pigment Yellow 110, 2 wt. % C.I. Pigment Red 122, and 2 wt. % C.I. Pigment Blue 15.
In the table below ΔE ab *, and Δb* are shown.
Comparative Example 2
Comparative example 2 was performed as example 1 with the only difference that instead of the C.I. Pigment Yellow 147 C.I. Pigment Yellow 139 was used.
C.I. Pigment Yellow 139 is 5,5′-(1H-Isoindole-1,3(2H)-diylidene)dibarbituric acid and therefore, does not fall under formula (I).
The resulting spun-dyed PPTA multifilament yarn contained 2 wt. % C.I. Pigment Yellow 139, 2 wt. % C.I. Pigment Red 122, and 2 wt. % C.I. Pigment Blue 15.
In the table below ΔE ab* , and Δb* are shown.
TABLE
Δb*
ΔE ab*
Example 1
0.10
0.7
Comparative example 1
0.30
1.2
Comparative example 2
2.45
2.7
The comparison of example 1 with comparative examples 1 and 2 in the table exhibits, that both Δb* and ΔE ab* of the spun-dyed PPTA-fibers containing C.I. Pigment Yellow 147 are significantly lower than Δb* and ΔE ab* of the spun-dyed PPTA-fibers containing C.I. Pigment Yellow 110 and C.I. Pigment Yellow 139.
So, the fastness of colouristic properties of the spun-dyed PPTA-fibers containing C.I. Pigment Yellow 147 is significantly better than the fastness of colouristic properties of the spun-dyed PPTA-fibers containing C.I. Pigment Yellow 110 and C.I. Pigment Yellow 139. | Spun-dyed aramid fibers, wherein spun-dyeing was performed with a completely organic pigment exhibiting the chemical structure of formula (I):
wherein, independently from one another, R 1 represents a substituent of formula X a or a substituent of formula X b :
wherein X a is linked via the group NH having two bonds in the structure represented by X a , while X b is linked via the carbon atom, which is in a para relationship with the NH 2 -group of X b ; and R 2 represents H or NH 2 . The spun-dyed aramid fibers exhibit constant coloristic properties and wash proof properties. | 3 |
This application is a National Stage Application of International Application Number PCT/IB01/02115, published, pursuant to PCT Article 21(2) which claims benefit of 60/232617, Sep. 14, 2000.
The present invention relates to novel Syn isomers of racemates and optical isomers of 3-(heteroaryl acetamido)-2-oxo-azetidine-1-sulfonic acids and its use in treating the infections caused by gram-negative pathogenic bacteria.
BACKGROUND OF INVENTION
Bacteria are very adaptable microorganisms that possess the ability to adapt and to survive under adverse conditions. Doctors in hospitals and clinics around the world are losing the battle against an onslaught of new drug resistant bacterial infections including those caused by Staphylococci, Streptococci, Enterococci and Pseudomonas.
Bacterial resistance to the current antibiotics has been on a steep rise due to the alteration of the target, a change in the permeability pattern or by efflux of active ingredient and by deactivation of the antibiotic before reaching the active site.
The β-lactam antibiotics (penicillins, cephalosporins, monobactams and carbapenems) are the most widely used group of antibiotics for the treatment of many infectious diseases, because of proven clinical efficacy and their excellent safety profile. Bacterial resistance towards gram-positive pathogens against β-lactam antibiotics is mainly due to the alteration of penicillin binding proteins (PBP's), efflux of active ingredient and deactivation of active ingredient. Whereas bacterial resistance towards gram-negative pathogens against β-lactam antibiotics in addition to those of the gram-positive pathogen, also are due to changes in outer membrane permeability pattern.
To overcome the changes in outer membrane permeability, in recent years a number of β-lactam compounds (cephem and monobactam) containing an iron chelating catecholic and dihydroxypyridone groups have been reported (29 Th ICAAC, Houston Tex., Sep. 18, 1989, abstract no. 355, 356; 30 th ICAAC, Atlanta, Ga., Oct. 22, 1990, abstract no. 458; Antimicrobial Agents and chemotherapy 1991, 35, 104-110). The potent activity of these compounds is due to their utilization of the TonB-dependent iron transport systems for transport across the bacterial outer membrane (Antimicrobial Agents and chemotherapy 1995, 39, 613-619).
Monobactams are a class of antibacterial agents and have been used to treat infections caused by gram-negative microorganisms. Currently Aztreonam and Carumonam are in clinical use. Quinoxaline directly attached to an oxime side chain of the monobactam nucleus is under development (Curr. Opin. Anti-infect. Drugs 1999, 1(1), 96-100; Antimicrobial Agents and Chemotherapy 1997, 41, 1010-1016). Further dihydroxypyridine through a methylene spacer attached to an oxime side chain in the anti orientiation is reported as β-lactamase inhibitor (U.S. Pat. No. 5,888,998 (1999)).
The present invention describes a class of compound in which a dihydroxypyridone group is directly or through a suitable spacer attached to an oxime side chain in a monobactam nucleus and its use to treat gram-negative infections, particularly those caused by Pseudomonas. Pseudomonas aeruginosa continues to be a very frequent opportunistic pathogen, capable of causing a wide variety of infections in the immunocompromised patient. These infections are often associated with significant morbidity and are difficult to treat.
SUMMARY OF THE INVENTION
It is an objective of the present invention to provide novel Syn isomers of racemates and optical isomers of 3-(heteroaryl acetamido)-2-oxo-azetidine-1-sulfonic acids of formula I having antibacterial activity against gram-negative pathogenic bacteria, particularly Pseudomonas strains.
It is a further object of the invention to provide pharmaceutical compositions comprising the compound of formula I with a pharmaceutically acceptable carrier or diluent.
It is an additional object of the invention to provide a method for treatment of bacterial infections caused by gram-negative pathogenic bacteria including Pseudomonas.
DETAILED DESCRIPTION OF THE INVENTION
In accordance with the present invention, there is provided novel Syn isomers of recemates and optical isomers of 3-(heteroaryl acetamido)-2-oxo-azetidine-1-sulfonic acids of formula I
Wherein
M is a hydrogen or a pharmaceutically acceptable salt forming cation; X is CH, N or C-halo; R is C 1 -C 3 allyl which is unsubstituted or substituted with at least one of (a) a halogen atom (b) OR 5 wherein R 5 is hydrogen, CONH 2 or 2,5-dihydroxy-4-oxo-1,4-dihydro-pyridin-2-yl-carbonyl and wherein a C 1 alkyl may not be substituted with both a halogen atom and OR 5 . R 1 and R 2 independently are OH, COOH, CONH 2 , optionally substituted phenyl or C 1 -C 3 alkyl; or R 1 and R 2 together are —O—CH═CH—CH 2 —, —O—CH 2 —CH 2 —O—, —CH 2 —CH 2 —CH 2 —, —CH 2 —CH 2 —CH 2 —CH 2 —, —CH═CH—CH═CH— or —CH═C(OH)—C(OH)═CH— which together with the carbon atoms to which they are bound form a 5 membered or six membered cyclic ring R 3 and R 4 independently are hydrogen, optionally substituted C 1 -C 3 alkyl, optionally substituted phenyl or C 3 -C 6 cycloalkyl; R 3 and R 4 together are C 3 -C 6 cycloalkyl.
As used herein, the term “C 1 -C 3 alkyl” means a straight or branch chain alkyl having 1-3 carbon atom selected from methyl, ethyl, propyl and isopropyl.
As used herein, the term “C 3 -C 6 cycloalkyl” means a saturated alicyclic moiety having 3-6 carbon atoms selected from cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl.
As used herein, the term “halogen atom” means fluorine, chlorine, or bromine.
As used herein, the term “substituted” as applied to a group means substituted with 1, 2 or 3 substituents selected from OH, NH 2 , dimethylamino, a halogen atom, OCH 3 , COOH, CONH 2 , NO 2 or CN.
As used herein, the term “racemate” means the mixture of diastereoisomers having zero optical rotation of the molecule of formula I.
As used herein, the term “optical isomers” means pure single R and S diastereoisomers at the asymmetric carbon atoms present in the molecule of formula I.
As used herein the term “pharmaceutically acceptable salt forming cation” means alkali metals (e.g. Sodium, Potassium), alkaline earth metals (e.g. Calcium, Magnesium), organic bases (e.g. triethylamine, ethanolamine, n-methylmorpholine) or basic amino acids (e.g. lysine, arginine, orithine or histidine). Moreover when M is hydrogen in formula I, it can form zwitterions (inner salt or internal salt) by interacting with a basic nitrogen atom present in the molecule of formula I.
In accordance with the preferred embodiment of the present invention, there is provided novel Syn isomers of racemates and optical isomers of 3-(heteroaryl acetamido)-2-oxo-azetidine-1-sulfonic acids and of formula I
Wherein
M is a hydrogen or pharmaceutically acceptable salt forming cation; X is CH; R is CH 3 , CH 2 F or CH 2 OCONH 2 . R 1 is OH R 2 is Hydrogen; R 1 and R 2 together is —CH═C(OH)—C(OH)═CH— which forms six member cyclic ring R 3 and R 4 independently is hydrogen; R 3 and R 4 together is cyclopropyl;
As used herein, the term “racemate” means the mixture of diastereoisomers having zero optical rotation of the molecule of formula I.
As used herein, the term “optical isomers” means pure single R and S diastereoisomers at the asymetric carbon atoms present in the molecule of formula I.
As used herein the term “pharmaceutically acceptable salt forming cation” means alkali metals (e.g. Sodium, Potassium). Moreover when M is hydrogen in formula I, it can form zwitterion (inner salt or internal salt) by interacting with a basic nitrogen atom present in the molecule of formula I.
The compounds of this invention can be used to treat bacterial infections caused by gram-negative bacteria, including but not limited to Pseudomonas E. eloaecae, C. freundii, M. Morganii, K. paeumoniae, and E. Coli alone or in combination with other drugs in mammals including humans. The compounds may be administered in pharmaceutical dosage forms including parenteral preparation such as injections, suppositories, aerosols and the like, and oral preparations such as tablets, coated tablets, powders, granules, capsules, liquids and the like. The above preparations are formulated in manners well known to the art.
For the formulation of solid preparations for oral administration, an excipient, and if desired, a binder, disintegrator, lubricant, coloring agent, corrigent, flavor etc. are added to the compound of the invention, and then tablets, coated tablets, granules, powders, capsules or the like are prepared in a conventional manner.
For the formulation of injections, a pH adjusting agent, buffer, stabilizer, isotonic agent, local anesthetic or the like is added to the active ingredient of the invention, and injections for subcutaneous, intramuscular or intravenous administration can be prepared in the conventional manner.
For the formulation of suppositories, a base, and if desired, surfactants are added to the active ingredient of the invention, and the suppositories are prepared in a conventional manner.
The excipients useful for solid preparations for oral administration are those generally used in the art, and the useful examples are excipients such as lactose, sucrose, sodium chloride, starches, calcium carbonate, kaolin, crystalline cellulose, methyl cellulose, glycerin, sodium alginate, gum arabic and the like, binders such as polyvinyl alcohol, polyvinyl ether, polyvinyl pyrrolidone, ethyl cellulose, gum arabic, schellac, sucrose, water, ethanol propanol, carboxymethyl cellulose, potassium phosphate and the like, lubricants such as magnesium stearate, talc and the like, and further include additives such as usual known coloring agents, disintegrators and the like. Examples of bases useful for the formulation of suppositories are oleaginous bases such as cacao butter, polyethylene glycol, lanolin, fatty acid triglycerides, witepsol (trademark, Dynamite Nobel Co. Ltd.) and the like. Liquid preparations may be in the form of aqueous or oleaginous suspension, solution, syrup, elixir and the like, which can be prepared by a conventional way using additives.
The amount of the compound I of the invention incorporated into the pharmaceutical composition of the invention varies with the dosage form, solubility and chemical properties of the compound, administration route, administration scheme and the like. Preferably the amount is about 1 to 25 w/w % in the case of oral preparations, and about 0.1 to 5 w/w % in the case of injections which are parenteral preparations.
The dosage of the compound I of the invention is suitably determined depending on the individual cases taking symptoms, age and sex of the subject and the like into consideration. Usually the dosage in the case of oral administration is about 50 to 1500 mg per day for an adult in 2 to 4 divided doses, and the dosage in the case of injection, for example, by intravenous administration is 2 ml (about 1 to 100 mg) which is administered once a day for adults wherein the injection may be diluted with physiological saline or glucose injection liquid if so desired, and slowly administered over at least 5 minutes. The dosage in case of suppositories is about 1 to 1000 mg which is administered once or twice a day at an interval of 6 to 12 hours wherein the suppositories are administered by insertion into the rectum.
The compounds of the present invention having the formula I can be prepared by reacting 3-amino-azetidine-2-one sulfonic acid of formula (II) with heteroaryl carboxylic acid of formula III followed by deprotection of the protecting group.
Certain derivatives of general formula IV were prepared by coupling of 3-amino-azetidine-2-one sulfonic acid (II) with a heteroaryl carboxylic acid (III) in presence of dicyclohexylcarbodiimide (DCC) or with an acid chloride of compound (III) in presence of base, or with an activated ester of compound (III) within the skill of the arts.
Alternatively, compounds of formula I can also be prepared as follows:
The preparation of compound II (R=CH 3 ) was carried out by following the synthetic scheme 2 as described in J. Org. Chem. 1982, 47, 5160-5167.
The preparation of compound II (R=CH 2 F, CH 2 OCONH 2 ) was carried out by following the synthetic scheme 3 from common intermediate compound V as described in J. Antibiotics 1983, 36, 1201-1204 and J. Antibiotics 1985, 38, 346-357.
The common intermediate compound V was prepared by following the synthetic route as described in scheme 4. The distereoisimers of compound VI are separated by optical resolution methods (J. Antibiotics 1985, 38, 346).
The preparation of compounds III was done by reacting 2-heteroaryl-2-oxo acetic acid (VII) with O-heteroaryl hydroxyl amine (VIII) at room temperature and afforded exclusively the syn-isomer. The preparation of compound VIII was done as described in Scheme 5 starting from heteroarylmethanol (J. Antibiotics 1990, 43, 189-198).
In the above descriptions (scheme 1-5), the reactants are reacted together with a suitable solvent at elevated or low temperatures for sufficient time to allow the reaction to proceed to completion. The reaction conditions will depend upon the nature and reactivity of the reactants. Wherever a base is used in a reaction, they are selected from triethylamine, tributylamine, trioctylamine, pyridine, 4-dimethylaminopyridine, diisopropylethylamine, 1,5-diazabicyclo[4,3,0]non-5-ene, 1,8-diazabicyclo[5,4,0]undec-7-ene, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate or cesium carbonate.
The deprotection of the protective group is carried out either by hydrogenation or by hydrolysis with appropriate acids such as hydrochloric acid, trifluoroacetic acid or acetic acid in solvent such as methanol, ethanol, propanol or ethyl acetate. The hydrogenation reaction is usually carried out in the presence of a metal catalyst, such as Pd, Pt, or Rh, under normal pressure to high pressure.
The solvents of choice for the reaction are selected based upon the reactants used and from such solvents as benzene, toluene, acetonitrile, tetrahydrofuran, ethanol, methanol, chloroform, ethyl acetate, methylene chloride, dimethyl formamide, dimethyl sulfoxide, hexamethyl phosphoric triamide, or the like. Solvent mixtures may also be utilized.
Reaction temperatures would generally range from between −70° C. to 150° C. The preferred molar ratio of reactants is 1:1 to 1:5. The reaction time range from 0.5 to 72 hours, depending on the reactants.
The present invention is further illustrated by the following non-limiting examples.
EXAMPLE 1
(3S)-trans-3-[(2-Amino)thiazol-4-yl)-(Z)-2-{(1,5-dihydroxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-methyl-2-oxoazetidine-1-sulfonic acid, sodium salt
Step 1: 1,5-Dibenzhydryloxy-2-(N-phthalimido)oxymethyl-4-pyridone
A solution of 1,5-dibenzhydryloxy-2-hydroxymethyl-4-pyridone (20.0 g, 0.041 mol) and N-hydroxyphthalimide (6.64 g, 0.048 mol) in a mixture of THF (200 ml) and dry DMF (200 ml) was treated with triphenyl phosphene under nitrogen and cooled to 0° C. The reaction mixture was then added with diethyl azodicarboxylate dropwise over 10 min., stirred at 0° C. for 1 h then diluted with ethyl acetate and water. The organic layer was separated, washed with water and brine, dried over sodium sulfate, filtered and evaporated in vacuo. The crude product obtained was purified by silica gel column chromatography using a gradient mixture of EA: Hexane (1:2 to 1:0) to give the pure title compound.
Yield: 19.0 g, 73% 1 HNMR (DMSO-d 6 ): δ 4.78(s, 2H), 6.24(s, 1H), 6.29(s, 1H), 6.46(s, 1H), 7.18-7.38(m, 20H), 7.62(s, 1H), 7.85(s, 4H).
Step 2: 2-(2-Tritylamino)-thiazol-4-yl)-(Z)-2-[1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy]-imino acetic acid.
A solution of 1,5-dibenzhydryloxy-2-(N-phthalimido)oxymethyl-4-pyridone (10 g, 15.8 mmol) in ethanol (98%, 100 ml) was treated with hydrazine (0.76 ml). The mixture was heated to reflux for 1 h. and cooled to RT. The suspension thus obtained was filtered and the filtrate was evaporated to dryness and was treated with chloroform. The solid thus separated was filtered off, the mother liquors were concentrated and the residue obtained was dissolved in ethanol (98%) then treated with a solution of 2-oxo-2-[(N-tritylamino)thiazol-5-yl]acetic acid (6.38 g) in chloroform. The reaction mixture was stirred at room temperature for 18 h and evaporated in vacuo. The residue obtained was dissolved in ethyl acetate and diluted with hexanes. The solid separated was filtered and dried to give 2-(2-tritylamino)thiazol-4-yl)-(Z)-2-[1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy]imino acetic acid.
Yield: 11.2 g, 79% 1 HNMR (DMSO-d 6 ): δ 4.62(s, 2H), 6.03(s, 1H), 6.28(s, 1H), 6.40(s, 1H), 6.66(s, 1H), 7.18-7.35(m, 35H), 7.48(s, 1H), 8.64(s, 1H).
Step 3: (3S)-trans-3-[2-(2-Tritylamino)thiazol-4-yl)-(Z)-2-{(1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-methyl-2-oxoazetidine-1-sulfonic acid.
A mixture of (3S)-trans-3-amino-4-methyl-2-oxoazetidine-1-sulfonic acid [7.30 g, 40.52 mmol, J. Org. Chem., 47, 5160, (1982)], 2-(2-tritylamino)thiazol-4-yl)-(Z)-2-[1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy]imino acetic acid (from step 36.50 g, 40.51 mmol), DCC (9.15 g, 44.34 mmol) and 1-hydroxybenzotriazole (5.47 g, 40.5 mmol) in dry DMF (400 ml) was stirred at room temperature for 30 min. and to this mixture NaHCO3 (3.40 g, 40.52 mmol) was added. The mixture was stirred under nitrogen at room temperature over night and filtered. The mother liquor was evaporated in vacuo to remove DMF and the residue obtained was dissolved in ethyl acetate and distilled water and adjusted to pH ˜3. The organic layer was dried over anhydrous sodium sulfate, filtered and evaporated in vacuo.
The product thus obtained was purified over HP-20 column chromatography using a gradient mixture of water:acetonitrile (1:0 to 1:9) to give the title compound.
Silica gel column chromatography using a gradient mixture of ethyl acetate: methanol (1:0 to 9:1) gave the title compound
Yield: 37.00 g, 85.9% 1 HNMR (DMSO-d 6 ): δ 1.29(d, 3H, J=6.0 Hz), 3.54-3.61(m, 1H), 4.30-4.35(m, 1H), 4.70(s, 2H), 5.98(s, 1H), 6.29(s, 2H), 6.71(s, 1H), 7.25-7.35(m, 35H), 7.51(s, 1H), 8.83(s, 1H), 9.39(d, 1H, J=7.7 Hz).
Step 4: (3S)-trans-3-[(2-Amino)thiazol-4-yl)-(Z)-2-{(1,5-dihydroxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-methyl-2-oxoazetidine-1-sulfonic acid.
A suspension of (3S)-trans-3-[-2-(2-tritylamino)thiazol-4-yl)-(Z)2-{(1,5-dibenzhydryloxy-4-pyridon-2-yl
methoxy)imino}acetamido]-4-methyl-2-oxoazetidine-1-sulfonic acid (5.00 g, 4.703 mmol) in dry anisole (14 ml) at −10° C., under nitrogen was treated with trifluoroacetic acid (25 ml) and stirred at 0° C. for 2 hrs. The solvents were evaporated under reduced pressure and the residue was triturated with a mixture of ether-hexane and ethyl acetate (1:1:1). The solid thus obtained was filtered, washed with a mixture of ether-hexane and ethyl acetate (1:1:1) to give a solid. The above solid was further purified by HP-20 column chromatography using a gradient mixture of distilled water and acetonitrile (1:0 to 9:1) and the appropriate fractions were lyophilized to give the title compound.
Yield: 2.7 g, 92%; mp: 200° C. decomp. 1 HNMR (DMSO d 6 ): δ 1.41(d, 3H, J=6.2 Hz), 3.70-3.80(m, 1H), 4.46(dd, 1H, J=2.4 Hz and 5.2 Hz), 5.30(s, 2H), 6.85(s, 1H), 7.05(s, 1H), 7.35(br, s, 2H), 8.17(s, 1H), 9.50(d, 1H, J=7.7 Hz).
Step 5: (3S)-trans-3-[(2-Amino)thiazol-4-yl)-(Z)-2-{(1,5-dihydroxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-methyl-2-oxoazetidine-1-sulfonic acid, sodium salt.
A suspension of (3S)-trans-3-[(Z)-(2-amino)thiazol-4-yl)-2-{(1,5-dihydroxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-methyl-2-oxoazetidine-1-sulfonic acid (1.30 g, 2.66 mmol) in distilled water (15 ml) was cooled to ˜5-6° C. and NaHCO3 (s, 0.223 g, 2.654 mmol) was added in portions with stirring. The clear solution thus obtained within 10 min. was filtered and lyophilized to give (3S)-trans-3-[{(2-amino)thiazol-4-yl)-(Z)-2-{(1,5-dihydroxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-methyl-2-oxoazetidine-1-sulfonic acid, sodium salt.
Yield: 1.32 g, 97.13%. 1 HNMR (DMSO-d 6 ): δ 1.42(d, 3H, J=6.1 Hz), 3.70-3.80(m, 1H), 4.48-4.53(m, 1H), 5.13(s, 2H), 6.64(s, 1H), 6.79(s, 1H), 7.24(br, s, 2H), 7.68(s, 1H), 9.52(d, 1H, J=7.0 Hz).
EXAMPLE 2
3-[2-(2-Aminothiazol-4-yl)-(Z)-2-{(1,5-dihydroxy-4-pyridon-2-yl methoxy)imino}-acetamido]-4-carbamoyloxymethyl-2-azetidinone-1-sulfonic acid, sodium salt
Step 1: 3-[2-(2-Tritylamino)-thiazol-4-yl)-(Z)-2-{(1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-carbamoyloxymethyl-2-azetidinone
A solution of 2-(2-tritylamino)-thiazol-4-yl)-(Z)-2-[1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy]imino acetic acid (0.34 g, 0.377 mmol) in dry DMF (20 ml) was treated with DCC (0.078 g, 0.377 mmol) and 1-hydroxybenzotriazole (0.050 g, 0.0377 mmol). The mixture was stirred under nitrogen at room temperature for 30 min. and to this mixture NaHCO 3 (0.032 g, 0.377 mmole) and 3-amino-4-carbamoyloxymethyl-2-azetidinone (0.06 g, 0.377 mmol) in DMF (5 ml) was added. The reaction mixture was stirred at room temperature for 18 hrs, and DMF was removed in vacuo. The product thus obtained was purified by silica gel column chromatography by a gradient mixture of ethyl acetate and methanol (10:1 to 9.5:0.5) to give the title compound.
Yield: 0.2 g, 97.13% 1 HNMR (DMSO-d 6 ): δ 3.80-3.92(m, 2H), 3.97-4.05(m, 1H), 4.70(s, 2H), 5.17-5.25(m, 1H), 6.00(s, 1H), 6.31(s, 1H), 6.53(br, s, 2H), 6.74(s, 1H), 7.24-7.38(m, 35H), 7.58(s, 1H), 8.50(s, 1H), 8.80(s, 1H), 9.29(d, 1H, J=9.0 Hz).
Step 2: 3-[{2-(2-Tritylamino)thiazol-4-yl)}-(Z)-2-{(1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-carbamoyloxymethyl-2-azetidinone-1-sulfonic acid
A solution of 3-[{2-(2-tritylamino)thiazol-4-yl)}-(Z)-2-{(1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-carbamoyloxymethyl-2-azetidinone (0.25 g, 0.244 mmol) in pyridine (2 ml) was treated with sulfur trioxide-pyridine complex (0.153 g, 0.96 mmol) and the mixture was heated at 70° C. for 45 min. The reaction mixture was cooled to RT, treated with diethyl ether and the solid was filtered, washed with distilled water followed by ether and dried to give ciss-3-[{2-(2-tritylamino)thiazol-4-yl)}-(Z)-2-{(1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-carbamoyloxy methyl-2-azetidinone-1-sulfonic acid.
Yield: 0.23 g, 85%
Step 3: 3-[2-(2-Tritylamino)-thiazol-4-yl)-(Z)-2-{(1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-carbamoyloxymethyl-2-azetidinone-1-sulfonic acid, sodium salt.
A suspension of 3-[2-(2-tritylamino)-thiazol-4-yl)-(Z)-2-{(1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-carbamoyloxymethyl-2-azetidinone-1-sulfonic acid (0.390 g, 0.353 mmol) in distilled water (10 ml) was treated with NaHCO 3 (s, 0.050 g, 0.595 mmol) and stirred at RT for 30 min. and the clear solution was lyophilized. The solid obtained was purified by HP-20 column chromatography using a gradient mixture of dd. Water and acetonitrile (1:0 to 3:7), and the appropriate fractions were lyophilized to give the to give 3-[2-(2-tritylamino)-thiazol-4-yl)-(Z)-2-{(1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-carbamoyloxymethyl-2-azetidinone-1-sulfonic acid, sodium salt.
Yield: 0.21 g, 52%
Step 4: 3-[2-(2-Aminothiazol-4-yl)-(Z)-2-{(1,5-dihydroxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-carbamoyloxymethyl-2-azetidinone-1-sulfonic acid.
A suspension of 3-[2-(2-tritylamino)thiazol-4-yl)-(Z)-2-{(1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-carbamoyloxymethyl-2-azetidinone-1-sulfonic acid, sodium salt (0.8 g, 0.874 mmol) in anisole (5 ml) under nitrogen atmosphere was cooled to ˜0° C. and treated with trifluoroacetic acid (25 ml) and the mixture was stirred at less than 10° C. for 2 hrs and treated with ether. The solid separated was filtered, washed with acetone and dissolved in a mixture of acetonitrile/dd: H 2 O and freeze dried to give the title compound.
Yield: 0.34 g, 89%; mp: 190° decomp. 1 HNMR (DMSO-d 6 ): δ 3.90-4.30(m, 3H), 5.22-5.40(m, 5H), 6.50(br, s, 2H), 6.82(s, 1H), 6.95(s, 1H), 7.33(br, s, 2H), 8.00(s, 1H), 9.45(d, 1H, J=7.5 Hz).
Step 5: 3-[2-(2-Aminothiazol-4-yl)-(Z)-2-{(1,5-dihydroxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-carbamoyloxymethyl-2-azetidinone-1-sulfonic acid, sodium salt
NaHCO 3 (s, 6 mg, 0.073 mmol) was added to a suspension of 3-[2-(2-Aminothiazol-4-yl)-(Z)-2-{(1,5-dihydroxy-4-pyridon-2-yl-methoxy)imino}-acetamido]-4-carbamoyloxymethyl-2-azetidinone-1-sulfonic acid (40 mg, 0.073 mmol) in distilled water. After stirring for 5 min. the mixture was freeze dried to give the title compound as a solid.
Yield: 30 mg, 71% 1 HNMR (DMSO-d 6 ): δ 4.03-4.15(m, 2H), 4.20-4.33(m, 1H), 5.12(s, 2H), 5.26-5.37(m, 1H), 6.54(br, s, 2H), 6.70(s, 1H), 6.77(s, 1H), 7.24(br, s, 2H), 7.72(s, 1H), 9.38(d, 1H, J=7.5 Hz).
EXAMPLE 3
3-[2-(2-Aminothiazol-4-yl)-(Z)-2-{(1,5-dihydroxy-4-pyridon-2-yl-methoxy)imino}-acetamido]-4-fluoromethyl-2-azetidinone-1-sulfonic acid, sodium salt
Step 1: 3-[2-(2-Tritylamino)-thiazol-4-yl)-(Z)-2-{(1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-fluoromethyl-2-azetidinone-1-sulfonic acid.
A solution of 3-(N-benzyloxycarbonyl)amino-4-fluoromethyl-2-azetidinone-1-sulfonic acid, tetrabutyl ammonium salt (0.5 g, 0.89 mmol) in DMF (20 ml) was treated with Pd—C (0.3 g) and the suspension was hydrogenated at 50 psi over 5 hrs. The suspension was filtered through celite and to the filtrate was added DCC (0.18 g, 0.89 mmol), 1-HBT (0.12 g, 0.89 mmol) followed by 2-{(2-tritylamino)-thiazol-4-yl}-(Z)-2-[1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy]imino acetic acid (0.4 g, 0.89 mmol). The reaction mixture was stirred at RT for 18 hrs and evaporated in vacuo. The residue was dissolved in acetone treated with potassium nonafluoroborate (0.6 g) in acetone and stirred for a further 18 hrs. The solvents were evaporated and the residue was treated with a mixture of Ethyl acetate-Ether-Hexane (1:1:1). The solid separated was filtered and purified by silica gel column chromatography using a gradient mixture of Ethyl acetate and methanol (10:1 to 9:1) to give the title compound.
Yield: 0.22 g, 42.8% 1 HNMR DMSO-d 6 ): δ 4.00-4.20(m, 2H), 4.40-4.50(m, 1H), 4.67(s, 2H), 5.16-5.24(m, 1H), 6.00(s, 1H), 6.32(s, 1H), 6.37(s, 1H), 6.67(s, 1H), 7.27-7.43(m, 35H), 7.63(s, 1H), 8.85(s, 1H), 9.46(d, 1H, J=9.0 Hz).
Step 2: 3-[2-(2-Aminothiazol-4-yl)-(Z)-2-{(1,5-dihydroxy-4-pyridon-2-yl methoxy) imino}-acetamido]-4-fluoromethyl-2-azetidinone-1-sulfonic acid, sodium salt
A suspension of 3-[2-(2-tritylamino)thiazol-4-yl)-(Z)-2-{(1,5-dibenzhydryloxy-4-pyridon-2-yl methoxy)imino}acetamido]-4-fluoromethyl-2-azetidinone-1-sulfonic acid (0.5 g, 0.46 mmol) in anisole (2 ml), under nitrogen at −10° C. was treated with trifluoroacetic acid (20 ml) and stirred at 5-10° C. for 2 hrs. The reaction mixture was evaporated in vacuo and the residue was triturated with a mixture of ether:ethyl acetate and hexanes (1:1:1). The solid separated was filtered, dissolved in acetonitrile, water mixture and freeze dried. The crude product obtained was further purified by HP-20 column chromatography using a gradient mixture of dd.H 2 O and acetonitrile (1:0 to 9.4:0.6) to give 3-[2-(2-aminothiazol-4-yl)-(Z)-2-{(1,5-dihydroxy-4-pyridon-2-yl methoxy)imino}-acetamido]-4-fluoromethyl-2-azetidinone-1-sulfonic acid.
Yield: 80 mg, 34%; M.pt.: 200° C. decomp. 1 HNMR (DMSO-d 6 ): δ 3.83-4.35(m, 2H), 4.47-4.63(m, 1H), 4.68-4.85(m, 1H), 5.28(s, 2H), 6.29(s, 1H), 7.03(s, 1H), 7.30(br, s, 3H), 8.12(s, 1H), 9.45(d, 1H, J=8.1 Hz).
Step 3: 3-[2-(2-Aminothiazol-4-yl)-(Z)-2-{(1,5-dihydroxy-4-pyridon-2-yl methoxy) imino}-acetamido]-4-fluoromethyl-2-azetidinone-1-sulfonic acid, sodium salt
NaHCO 3 (s, 13 mg, 0.155 mmol) was added to a suspension of 3-[2-(2-Aminothiazol-4yl)-(Z)-2-{(1,5-dihydroxy-4-pyridon-2-yl-methoxy)imino}-acetamido]-4-fluoromethyl-2-azetidinone-1-sulfonic acid (80 mg, 0.158 mmol) in distilled water. The mixture was stirred for 5 min. and freeze dried to give 3-[2-(2-aminothiazol-4-yl)-(Z)-2-{(1,5-dihydroxy-4-pyridon-2-yl methoxy)imino}-3-acetamido]-4-fluoromethyl-2-azetidinone-1-sulfonic acid, sodium salt
Yield: 75 mg, 89% 1 HNMR (DMSO-d 6 ): δ 3.83-4.30(m, 2H), 4.47-4.64(m, 1H), 4.73-4.84(m, 1H), 5.13(s, 2H), 5.30(s, 1H), 6.55(s, 1H), 6.74(s, 1H), 7.27(br, s, 2H), 7.57(s, 1H), 9.57(br, s, 1H).
Test for Antibacterial Activity
The compounds of the present invention were tested for minimum inhibitory concentration (MIC) against the bacteria listed in Table-1 according to the standard microbroth dilution method as described in NCCLS document. The minimum inhibitory concentration is expressed in μg/ml.
TABLE 1
Antibacterial activity of the compounds of formula I
Tested compounds (MIC in μg/ml)
Organisms
1
2
3
Aztreonam
Carumonam
E. coli
0.06
0.06
0.06
0.06
0.06
TEM-2
K pneumoniae
0.13
0.06
0.06
0.06
0.06
K-1150
M Morganii
0.06
0.13
0.06
0.06
0.06
K 1250
C. freundii
0.13
0.50
0.50
0.13
0.06
K 500
E. cloaacae
0.06
0.25
2.0
0.13
0.06
S 480-2
P. aeruginosa
0.06
0.06
0.06
32
8.0
CL 1267
P. aeruginosa
0.13
0.13
0.13
32
8
S 1598
P. aeruginosa
4.0
128
32
64
32
PD 2721 | The present invention relates to novel Syn isomers of racemates and optical isomers of 3-(heteroaryl acetamido)-2-oxo-azetidine-1-sulfonic acids of the following formula:
and their use in treating infections caused by gram-negative pathogenic bacteria. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The subject application is the U.S. National Phase of PCT/DE02/04611, filed Dec. 17, 2003; published as WO 03/055777 A1 on Jul. 10, 2003 and claiming priority to DE 101 53 211.8, filed Dec. 21, 2001.
FIELD OF THE INVENTION
[0002] The present invention is directed to a device for making folded products. A folding hopper structure has at least two folding hoppers for producing at least two longitudinally folded strands.
BACKGROUND OF THE INVENTION
[0003] A hopper structure for a double-width printing press is known from DE 32 37 504 A1. Longitudinally folded strands from two hoppers, which are arranged side-by-side, can be selectively conducted to one of two folders arranged underneath them. Alternatively, each strand can be conducted to either one of the two folders.
[0004] A hopper structure for a triple-width printing press is known from DE 25 10 057 A1, which hopper structure has three upper hoppers and three lower hoppers, each arranged side-by-side. The strands run over guide rollers and a dancer roller assigned to the respective strand, by use of which rollers their linear register can be set before they are conducted together to a gap of the folder.
[0005] DE 41 28 797 C2 shows an arrangement of several hoppers for the longitudinal folding of strands of paper webs. The folded strands can be selectively conducted to a first folder, to a second folder, or to both folders arranged underneath.
[0006] A folding structure is known from DE 44 30 693 A1. Folded strands can be conducted by hoppers, via individually motor-driven traction and transfer rollers, to two folders which are individually motor-driven.
[0007] DE 41 37 818 A1 discloses a hopper structure with at least two side-by-side arranged hoppers. Traction rollers, each with an rpm-adjustable drive mechanism, are provided for adjusting the tension in the strands leaving the hoppers.
SUMMARY OF THE INVENTION
[0008] The object of the present invention is directed to providing a device for making folded products.
[0009] In accordance with the present invention, the object is attained by the provision of a hopper structure having at least two hoppers, or funnels, for producing at least two longitudinally formed and then folded strands. At least one register device may be provided for establishing a path of at least one of the strands between the hoppers and an entry into a folder. The hoppers, subsequent folding rollers and subsequent folders are arranged on different levels.
[0010] The advantages to be gained the present invention lie, in particular, in that a great flexibility in the products of a printing press is created. Additionally, the outlay and the costs in regard to the guidance and register regulation of individual strands are kept low.
[0011] In an advantageous embodiment of the present invention, the tracks and direction changes of the strands are kept low and comparable for all strands. This in turn, favors the reduction of regulation and an improvement of the product quality.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] A preferred embodiment of the device for producing folded products, in accordance with the present invention, is represented in the drawings and will be described in greater detail in what follows.
[0013] Shown are in:
[0014] FIG. 1 , a first preferred embodiment of a device for making folded products in accordance with the present invention, in
[0015] FIG. 2 , a second preferred embodiment of a device for making folded products, in
[0016] FIG. 3 , an alternative embodiment of the first preferred embodiment, and in
[0017] FIG. 4 , an alternative embodiment of the second preferred embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] A printing press, and in particular a web-fed rotary printing press, has one or several printing groups or printing units, which are not specifically represented, and by the use of which, at least one web 01 of material to be imprinted, hereinafter web 01 for short, can be imprinted. The printing units are embodied to be “double wide”, for example. This means that the printing cylinders have a length which corresponds to at least four printed pages, for example newspaper pages in Rhenic, Berlin, New York Times format, or the like, or to eight horizontal pages in tabloid format, for example, such as pages of a telephone directory, for example.
[0019] After the double-width web 01 , or after the double-width web 01 , depicted in FIG. 1 , i.e. after four printed pages, of a width b 01 , of the web 01 , have been imprinted in the printing units, they are conveyed to a hopper structure 02 for further processing. On the way to hopper structure 02 , they are cut, in the longitudinal direction, into two partial webs 01 a , 01 b by a cutting device, which is not specifically represented, and are combined respectively into a web strand 03 or 04 . Three cutting devices can also be arranged for printing in tabloid format, which three cutting devices cut the webs 01 longitudinally into quarters and into a corresponding number of web strands. In FIG. 1 combining the webs 01 into the web strand 03 , 04 takes place by the use of a separate roller 06 , or a group of rollers 06 , before the strand 03 , 04 is afterwards conducted via a roller 07 , for example via a hopper roller 07 , to respective hoppers or funnels 08 , 09 , for example embodied as so-called double hoppers or funnels 08 , 09 . The hoppers 08 , 09 are preferably each arranged aligned with the one of respective partial web 01 a , 01 b . During so-called “straight forward operations” the partial webs 01 a , 01 b run up on the respective hoppers 08 , 09 without an offset. In an advantageous embodiment, the web combining roller 06 and the hopper roller 07 each have their own drive motors 11 , 12 , by the use of which separate roller drive motors 11 , 12 the web tension can be set or adjusted. In a further development, the web combining roller 06 and/or the hopper roller 07 can be embodied as rollers 06 , 07 which are divided over their length into partial roller elements, and each such partial roller element can be driven by its own drive motor 11 , 12 , each represented twice in dashed lines in FIG. 1 . Also, respectively two partial rollers 06 , 07 , not having a common core, can be arranged with their end faces or fronts directed toward each other, and each can be driven independently of the other by the use of their own drive motor 11 , 12 .
[0020] At least one pair of rollers 13 , 14 , which may be, for example, folding rollers 13 , 14 , and at least one traction roller 16 , 17 are arranged downstream of each hopper 08 , 09 , respectively. In the first preferred embodiment depicted in FIG. 1 , a pair of folding rollers 13 , 14 and two traction roller groups 16 , 17 , for example one traction roller with contact rollers or contact cylinders acting together, are respectively, arranged downstream of each hopper 08 , 09 . The last traction roller group 16 , 17 , which constitutes a traction roller group nip 16 , 17 , is the structural termination of the respective folding or forming hopper or funnel 08 , 09 , in a running direction of the respective strand 03 , 04 in the direction toward a folding unit 18 , and, as a rule, this traction roller group nip is arranged at a fixed distance from the hopper 08 , 09 , except for any possible adjusting or mounting purposes.
[0021] The folding unit 18 is arranged downstream of the hopper structure 02 and has two folders 19 , 21 , or two folding groups 19 , 21 of a double folder. In an advantageous embodiment of the present invention, the hoppers 08 , 09 and the folders 19 , 21 are arranged on directly adjoining feed levels, so that they are without any further intervening units, which intervening units would interfere with, or would extend the course of the web, such further units typically being configured as further hoppers, etc. In an advantageous embodiment, and as schematically represented in FIG. 1 , the two folders 19 , 21 each have their own drive motors 22 , 23 . The two strands 03 , 04 can be fed selectively together to one of the folders 19 , 21 , or respectively each individually to one of the folders 19 , 21 .
[0022] The two folders 19 , 21 are advantageously aligned, in respect to each other and to the two hoppers 08 , 09 , in such a way that the strands 03 , 04 can be fed to the two folders 19 , 21 over the shortest possible distance.
[0023] A first reference point 24 , 26 , for example a first folder nip 24 , 26 , which is represented in FIG. 1 by a roller group 24 , 26 and which is a fixed part of the folder 19 , 21 , is assigned to each folder 19 , 21 , and acts together with the strands 03 , 04 , or the strands 03 , 04 . In an advantageous embodiment of the present invention, the two folders 19 , 21 are embodied, or are arranged, in such a way that an uninterrupted path of the strand 03 , 04 from the respectively last traction roller nip 16 , 17 of the hoppers 08 , 09 to the first folder nip 26 , 24 of the folder 21 , 29 , which are arranged in the shape of a cross underneath, is substantially of the same length in each case. This means that a distance a 03 , a 04 from the traction roller nip 16 , 17 of the hopper 08 , 09 is configured to be approximately equal to a distance a 04 , a 03 from the traction roller nip 17 , 16 of the hopper 09 , 08 to the first folder nip 24 , 26 of the folder 19 , 21 . The distances a 04 , a 03 can differ from each other maximally by 200 mm, however preferably by 100 mm, in particular by up to 50 mm.
[0024] The two folders 19 , 21 are, for example, arranged in such a way that each of the first folder nips 24 , 26 is located symmetrically, with respect to a center plane M extending between the two hoppers 08 , 09 . The center plane M is located parallel to, and centered between the two planes which extend through the longitudinally folded strands 03 , 04 in the area of the last folding rollers 13 , 14 , or in the area of the traction rollers 16 , 17 assigned to the hoppers 08 , 09 . As a rule, these latter planes coincide with the symmetry planes E 08 , E 09 of the hoppers 08 , 09 , such as represented in FIG. 1 .
[0025] For rerouting the paths, or for setting the paths to be travelled by the two strands 03 , 04 between the hoppers 08 , 09 and the folders 19 , 21 , at least one register device 27 is provided. A position of the at least one register device 27 can be changed and this at least one register device 27 is assigned to the two strands 03 , 04 . The movement of a positional change of register device 27 has at least one component which is parallel in respect to the normal plane of the strands 03 , 04 acting together in the area where they touch. In an advantageous embodiment, the register device 27 can be rotatorily driven by its own drive motor, which is not specifically represented, and its position can be changed by the use of an actuating drive, which also is not specifically represented. For example, the register device 27 can be pivotable along a curved line around a pivot axis S, or can be movable in the vertical direction. Depending on its position, the register device 27 acts in different ways with the strands 03 , 04 , which different ways of register device 27 action will be explained in greater detail in what follows.
[0026] In a first mode of operation of the device for producing folded products in accordance with the present invention, it is intended to produce a product in which the web strands 03 , 04 of both hoppers 08 , 09 are conducted to one of the two folders 19 , 21 . This one of the folders is the folder 21 , as is shown in FIG. 1 . The register device 27 , which is common to both strands 03 , 04 , has now been pivoted or shifted about its pivot axis S in such a way that a total path to be travelled by the strand 04 between the traction roller nip 17 and the first folder nip 26 corresponds to a total path to be travelled by the strand 03 between the nips 16 and 26 .
[0027] In an advantageous embodiment of the present invention, the register device 27 acts together selectively only with one strand 04 , 03 , here the strand 04 , while the other strand 03 , 04 runs undisturbed through the register unit 27 , i.e. runs through the register unit 27 without an operative connection with the register unit 27 . In this mode of operation, a resultant path S 04 , which is composed of the partial paths s 1 , s 2 , of the strand 04 has a distance which corresponds to the distance a 03 , all as seen in FIG. 1 .
[0028] If now, in a second mode of operation, in which production is to take place on the other folder 19 , the register device 27 , which is assigned to the two strands 03 , 04 , is brought into a second position in which second position, the conditions of the running of the strands 03 , 04 , which prevail, are reversed with respect to the first mode of operation discussed above. Again, the paths S 03 , S 04 are of the same length. For example, the strand 04 now extends without an operative connection with the register device 27 . For reasons of clarity, the paths for the second mode of operation are not specifically represented in FIG. 1 . Only the register unit 27 is indicated in FIG. 1 in dashed lines in its second position.
[0029] In the first preferred embodiment, which is shown in FIG. 1 , the register device 27 has two rollers 28 , 29 , for example two register rollers 28 , 29 , which are arranged so that their positions can be changed together. In a simple embodiment, these two register rollers 28 , 29 are arranged with their axes of rotation at a fixed distance from each other. If they are rotatorily driven by a drive mechanism, for example by a common drive motor, the drive mechanism should be configured in such a way that there is a direction of rotation in opposite directions. However, the two register rollers 28 , 29 can also each be driven by their own separate drive motors. In FIG. 1 , the two register rollers 28 , 29 are arranged in a common support 31 , or frame 31 , which common support 31 or frame 31 is pivotable around the pivot axis S, which is fixed in respect to the frame and which extends in a plane parallel in respect to one of the folded strands 03 , 04 , and vertically in respect to its conveying direction. In an advantageous embodiment, because it is symmetrical, the pivot axis S is also arranged lying in the center plane M. The register device 27 is shown magnified or enlarged in FIG. 1 .
[0030] In the mode of operation which is shown in solid lines in FIG. 1 , the register roller 29 close to the hopper 09 acts together with the strand 04 in the above described manner. A distance “a”, as is seen in FIG. 3 , between the two register rollers 28 , 29 has been selected, for example, in such a way that, taking into consideration the required pivot path, the register roller 28 , 29 assigned to the other strand 03 is not in operative connection with that other strand 03 .
[0031] In a second mode of operation, as shown in FIG. 2 , the register device 27 only has a single roller 32 , for example a single register roller 32 , which selectively acts together with only one of the two strands 03 , 04 in the manner described above with respect to the paths S 03 , S 04 . In the first mode of operation, the register roller 32 acts together with the strand 04 , as represented in solid lines in FIG. 2 . Here, the single register roller 32 is not located between the two strands 03 , 04 , but is located on the side of the strand 04 to be rerouted, which side of strand 04 faces away from the other strand 03 . The second mode of operation is again represented by a depiction of the single register roller 32 in dashed lines. The conditions regarding the path of the web and the position regarding the register roller 32 are symmetrical to or a mirror image of those from the first mode of operation of the register device shown in FIG. 2 . If the roller 32 is embodied as a driven roller, for example by being driven through a gear from other units, or by its own rotatory drive motor, the drive mechanism should be provided as having an option for reversing the direction of rotation.
[0032] In a third mode of operation of this second embodiment, the register roller 32 can be in a position without contact with either one of the two strands 03 , 04 . Now production can take place with both strands 03 , 04 each on one of the folders 19 , 21 respectively.
[0033] In another embodiment of the construction of the register device 27 , it is not arranged pivotable around the pivot axis S, but instead is movable linearly, and, in an advantageous manner, is also movable vertically in respect to the center plane M, in a frame, which is not specifically represented in FIGS. 3 and 4 . This applies correspondingly to the embodiments of the register device 27 in accordance with the first and second exemplary embodiments which are FIGS. 1 and 2 .
[0034] The embodiment of the register device 27 with its own rotatory drive mechanism makes possible, on the one hand, a tension regulation, or at least an improved conveying behavior when conveying the strand 03 , 04 , and, on the other hand, also makes possible a reversal of the direction of rotation of the register roller or rollers without a large outlay in gear technology.
[0035] It is possible, by the use of the device in accordance with the present invention, for example during collecting operations and when utilizing “double-large” printing cylinders, such as when using a forme cylinder that has a circumference corresponding to two standing printed pages and, if necessary, also including non-printing parts, such as fastening devices, etc., to create a product with four books. If there is no collection, or if the forme cylinders merely have a single circumference, two books can be produced. The four or two books can be selectively conducted to one of the two folders 19 , 21 , or can be split up to both of the two folders 19 , 21 .
[0036] If the device in accordance with the present invention is integrated into a hopper structure 02 with additional hoppers, which are not specifically represented, which hoppers, for example, are arranged as a further double hopper above the hoppers 08 , 09 , the flexibility, with regard to possible products, is considerably increased. The webs, or the strands 33 , coming from these hoppers can be additionally conducted to the folders 19 , 21 on a direct path, or via the register device 27 . This applies, in particular, if these hoppers and/or their guide devices, are arranged symmetrically with respect to the center plane M.
[0037] The embodiment of the register device 27 with two register rollers 28 , 29 , as seen in FIG. 1 , can be used in the situation of further hoppers which are not specifically represented, and which are arranged above the hoppers 08 , 09 , in particular also for an additional strand 33 , or strands 33 as shown in dashed lines in FIG. 1 . In case the strands 33 have already been adjusted in their own linear register by their own devices, they can be additionally conducted over one of the rollers 28 , 29 to one or both strands 03 , 04 . However, in a further development of the present invention, the distance “a” between the two rollers 28 , 29 can also be embodied to be adjustable, for example by the use of a drive mechanism. In this further embodiment, one or several of the strands 33 coming from above, as shown in dashed lines in FIG. 1 can be conducted over a roller 28 which does not act together with a lower strand 03 , 04 , and its linear register can be set by setting the distance “a”. Then, this strand 33 can be conducted, either together with the lower strands 03 , 04 to the same folder 21 or, relative to a further strand 33 , a further strand 33 whose linear register has been set, conducted to the folder 19 . In this case, the two rollers 28 , 29 are without their own drive mechanism, or are each embodied with their own drive motor.
[0038] While preferred embodiments of a device for producing folded products, in accordance with the present invention, have been set forth fully and completely hereinabove, it will be apparent to one of skill in the art that various changes in, for example, the type of press used to print the web or webs, the longitudinal cutting devices for the webs and the like, could be made without departing from the true spirit and scope of the present invention which is accordingly to be limited only by the following claims. | A device for providing folded products utilizes a funnel-shaped structure that consists of at least two funnels that are usable for providing two longitudinally folded strands or webs. A register device is usable for adjusting a path of at least one of the strands or webs between the funnel and the entrance to a folding machine. The register device can be associated with both of the strands or webs. | 1 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to European patent application No. 04253931.2, filed 30 Jun. 2004, which is hereby incorporated by reference as if fully disclosed herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a frame section of a frame for a black-out blind assembly, in particular for reducing the transmission of light through the blind assembly.
[0004] 2. Description of the Related Art
[0005] It is well known to provide black-out blinds for architectural openings. These blinds are used to cover openings, such as windows, to cover the opening and prevent ingress of any light. Examples of such blinds are described in U.S. Pat. No. 2,354,489, U.S. Pat. No. 5,117,892, DE 1 127 555 and DE 1 705 816.
[0006] Although the blinds themselves can be sufficiently opaque to produce the desired effect, there is a problem that light can be reflected within the frame supporting the blind, such that this light travels around the side of the blind.
[0007] To overcome this problem, the prior art proposes coating or painting inside surfaces of the frame of the black-out blind. However, the process of painting or coating the components in this way is undesirably complicated and expensive.
SUMMARY OF THE INVENTION
[0008] According to the present invention, there is provide a frame section of a frame for a black-out blind assembly supporting a black-out blind moveable within the frame between open and closed positions, the frame section having:
inner and outer walls extending from a side wall so as to form a channel section defining a recess for receiving part of a black-out blind; and a light absorbing substantially non-reflective insert positioned within the recess of the channel section adjacent the inner, outer and side walls.
[0011] In this way, it is not necessary to paint or coat inner portions of the frame which surround the sides of the black-out blind between the inside and the outside of the architectural opening. Painting and/or coating frame sections can be a problem, since, usually, it is only the innermost part of the frame section which needs to be light absorbing and non-reflective. It then becomes necessary to coat the frame section selectively.
[0012] By means of the present invention, it becomes a simple matter to prevent stray light from being reflected around the sides of the black-out blind. The separately manufactured insert can easily be inserted into the frame section.
[0013] Preferably, the insert is a sheet form extending between first and second parallel edges and is deformed so as to extend from the first edge adjacent the inner wall around the inside of the channel section to the second edge adjacent the outer wall.
[0014] By providing the insert as a sheet of appropriate width, it becomes very simple and inexpensive to manufacture the insert. Assembly of the frame section is not difficult, because it is only necessary to deform the sheet appropriately to fit it into the channel section.
[0015] Preferably, within the recess of the channel section, the inner and outer walls are provided with respective supports for receiving the first and second edges of the insert.
[0016] In this way, the insert is easily and securely held in place within the channel section.
[0017] The supports can include protrusions extending into the recess of the channel section so as to prevent the edges of the insert moving outwardly of the channel section.
[0018] The supports need not in themselves fix the edges of the insert to the inner and outer walls. By preventing the edges from moving outwardly of the channel section, the insert is effectively held securely in place. This is because it extends around the inside of the channel section and, hence, as a whole, cannot move such that its edges move inwardly of the channel section.
[0019] The supports can define respective openings facing inwardly of the recess of the channel section for receiving the edges of the insert.
[0020] The openings can prevent the edges not only moving outwardly of the channel section, but also from moving away from the inner and outer walls.
[0021] The supports can form elongate channels.
[0022] The edges of the insert fit into the elongate channels so as to secure them in place with respect to the inner and outer walls.
[0023] Preferably, the insert is at least partly resilient such that, once inserted in the recess of the channel section, the insert presses outwardly against the inner, outer and side walls.
[0024] In this way, it is not necessary to form accurately the insert before it is located in the channel section. The resilience of the insert causes it to follow generally the form of the channel section automatically. This also ensures that the insert does not interfere with the space of the recess or movement of the black-out blind within the recess.
[0025] The insert is preferably a black material. It may be made of a non-woven material, paper, woven fabric, non-woven fabric, extruded flat film, extruded film in shape, etc.
[0026] Frame sections of the present invention may be used for the sides of frames where a rolled black-out blind is unrolled from one end to the other along the length of the sides. In this case, a frame section can be arranged to receive an edge of a sheet forming a black-out blind, the edge sliding along the channel section as the black-out blind is moved between open and closed positions.
[0027] Frame sections can also be used for ends of the frame.
[0028] Hence, the frame section can be arranged to receive the rolled sheet forming a black-out blind, the sheet being unrolled from and rolled into the frame section as the black-out blind is moved between open and closed positions.
[0029] Since a black-out blind will generally have a predefined thickness, it is possible to design the sides of a frame with channel sections having a width corresponding to the thickness of the blind and, hence, minimising any scattered/reflected light around the sides of the black-out blind. However, particularly for the end part of the frame in which the blind is rolled and unrolled, there is a problem of light reflection. The end part has to have a sufficiently large recess to accommodate a fully rolled black-out blind. As a result, when the blind is unrolled, there is a large space within the recess around which light can be reflected.
[0030] The present invention provides a very effective arrangement for overcoming this problem.
[0031] Preferably, where the frame section is arranged to receive a rolled sheet, the frame section further includes a rotatable support at each of two ends of the frame section for supporting therebetween a rolled sheet forming a black-out blind.
[0032] According to the present invention, there is also provided a black-out blind assembly, including a frame having at least one frame section as described above, together with a black-out blind moveable within the frame.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 illustrates a black-out blind assembly in which the present invention may be embodied;
[0034] FIG. 2 illustrates a cross section through the head rail of the assembly of FIG. 1 showing also a top portion of the side guide; and
[0035] FIGS. 3 and 4 illustrate perspective views of the portion of FIG. 2 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0036] The invention will be more clearly understood from the following description, given by way of example only, with reference to the accompanying drawings.
[0037] The present invention is described with reference to an embodiment of a black-out blind assembly for a window opening, but can, of course, be used with any architectural opening. Indeed, it is described with reference to a blind which unrolls from the top of the frame. It will be appreciated that the frame can be positioned in any orientation and the black-out blind deployed in any appropriate direction.
[0038] As illustrated in FIG. 1 , within a window frame 2 is mounted a black-out blind assembly 4 .
[0039] The black-out blind assembly 4 includes a head rail 6 mounted at the top of the frame 2 and two side guides 8 and 10 which extend respectively from each end of the head rail 6 along opposite sides of the frame 2 . A black-out blind 12 may be deployed downwardly from the head rail 6 with its two opposing edges contained within channel sections of the side guides 8 and 10 .
[0040] As illustrated, a hand rail 14 is provided to enable a user to move the black-out blind up or down.
[0041] The black-out blind 12 is opaque such that, once fully deployed with the hand rail 14 at the bottom of the frame 2 , the black-out blind assembly prevents light from travelling past the frame 2 .
[0042] FIGS. 2, 3 and 4 illustrate further details of the side guide 10 and head rail 6 in the top left hand corner of the frame illustrated in FIG. 1 .
[0043] The side guide 10 has an inner wall 20 , on the inside face of the blind assembly 4 , an outer wall 22 , on the outside face of the blind assembly 4 , and a side wall 24 from which these two generally parallel walls extend.
[0044] Thus, as illustrated, the inner, outer and side walls form a channel section 26 . The channel section 26 defines an elongate recess along which an edge of the black-out blind may slide up and down (as illustrated in FIG. 1 ).
[0045] Inevitably, in practice, there will be slight gaps between the outside surface of the black-out blind and the face of the outer wall 22 which faces the channel section 26 . Hence, it is possible that light will enter into the channel section 26 . This light could reflect off the surfaces of the outer wall 22 , side wall 24 and inner wall 26 before escaping on the opposite side of the black-out blind through slight gaps between the inner wall 20 and the inside surface of the black-out blind 12 .
[0046] To overcome this problem, an insert 30 is provided within the channel section 26 .
[0047] The insert 30 has a light absorbing substantially non-reflective surface and is, for instance, matt black.
[0048] The insert 30 could be pre-formed of any suitable material for insertion into the channel section 26 . However, in a preferred embodiment, the insert 30 is formed as an elongate sheet extending between a first edge 32 and a second edge 34 . The sheet is merely deformed in the manner of bending or folding to insert it into the channel section 26 .
[0049] As illustrated, the first edge 32 is positioned adjacent the inner wall 20 whilst the second edge 34 is positioned adjacent the outer wall 22 . The sheet then extends around the periphery of the channel section 26 providing the required light absorbing properties without interfering with the sliding motion of the edge of the black-out blind in the channel section 26 .
[0050] By providing the sheet as a resilient member, it will inherently be biased outwardly and, hence, conform to the inner profile of the channel section 26 .
[0051] Thus, in the preferred embodiment, the insert 30 is a black non-woven relatively resilient material.
[0052] As illustrated, the inner wall 26 and outer wall 22 are provided with respective flanges 40 and 42 which extend towards one another and inwardly with respect to the channel section 26 . These flanges 40 and 42 form supports for the edges 32 and 34 of the insert 30 . In particular, flange 40 prevents the edge 32 from moving outwardly of the channel section and flange 42 prevents the edge 34 from moving outwardly of the channel section. Hence, the insert 30 is held securely in place within the channel section 26 .
[0053] It will be appreciated that, in this preferred embodiment, the side guide 8 has a similar form and is provided with a corresponding insert.
[0054] The head rail 6 also has a similar arrangement with an inner wall 120 on the inside of the frame 2 and a generally parallel outer wall 122 on the outside of the frame 2 . A side wall 124 joins the inner wall 120 and outer wall 122 , but, as compared with the side guide 10 , these walls form a channel section 126 which has a partially circular cross section as compared with the more rectangular cross section of the channel section 26 .
[0055] The recess defined by the channel section 126 forms a space in which the black-out blind 12 may be rolled. In this respect, an end cap 16 , 18 is provided at each respective end of the guide rail 6 . As illustrated most clearly in FIG. 3 , an inner portion of each end cap 16 , 18 is provided with a support 60 on which a roll of black-out blind may be rotatably mounted. Although not of direct relevance to the present invention, the blind assembly may additionally be provided with mechanisms for retracting the black-out blind by re-rolling it or, indeed, mechanisms for motorised operation of the blind.
[0056] Similarly to with the side guide 10 , an insert 130 is provided within the recess of the channel section 126 . The insert 130 is light absorbing and substantially non-reflective. As with the insert 30 , the insert 130 could be pre-formed for insertion and constructed of any suitable material. However, in the preferred embodiment, the insert 130 has a sheet form extending from a first edge 132 to a second edge 134 . The first edge is positioned adjacent the inner wall 120 and the second edge is positioned adjacent the outer wall 122 .
[0057] It will be noted that, for the arrangement of the side guide 10 in the preferred embodiment, the insert extends along substantially all of the depth of the inner and outer walls 20 and 22 . However, as is clear from FIG. 2 , it is not always necessary for the insert to extend up the entire wall. In particular, for FIG. 2 , the second edge 134 of the insert 130 extends only as far as the innermost part of the outer wall 122 .
[0058] As with the insert 30 , the insert 130 is preferably at least partly resilient. In this way, as illustrated, the insert 130 is naturally biased so as to conform to the inner surface of the channel section 126 .
[0059] The inner wall 120 is provided with a flange 140 which projects inwardly of the channel section 126 . This provides a step against which the first edge 132 of the insert 130 abuts. The flange 140 thus forms a support which prevents the first edge 132 from moving outwardly of the channel section 126 .
[0060] The outer wall 122 is formed with an inwardly facing elongate channel 142 into which the second edge 134 of the insert 130 is mounted. In this way, the elongate channel 142 provides a support for preventing the second edge 134 for moving outwardly of the channel section 126 .
[0061] The insert 130 is thus easily held in place with the channel section 126 . By conforming generally to the inner surface of the channel section 126 , the insert 130 does not interfere with rolling or unrolling of the black-out blind and yet still provides the necessary properties for preventing or at least reducing reflection of light.
[0062] It will be appreciated that the supports for the edges of the inserts can be provided in other ways using any suitable form of rib, flange, groove, etc.
[0063] It will also be appreciated that similar inserts can be provided with side guides and head rails of other cross sections. For instance, similar inserts could be used with the frame sections described in EP 1 045 111 and also EP 0 841 461, DE 44 06 287, U.S. Pat. No. 4,357,978 and GB 2 235 005 to which it refers.
[0064] International Design No. DM/052193 of 5 Aug. 1999 illustrates other frame cross sections in which the present invention could be embodied. | A black-out blind assembly having a frame supporting a black-out blind moveable within the frame between open and closed positions wherein sections of the frame have inner and outer walls extending from a side wall so as to form a channel section defining a recess for receiving part of a black-out blind. A light absorbing substantially non-reflective insert is positioned within the recess of the channel section adjacent the inner, outer and side walls so as to prevent scattered and reflected light passing around the sides of the black-out blind. | 4 |
This is a continuation of application Ser. No. 09/618,711, filed Jul. 18, 2000, which is as U.S. Pat. No. 6,354,344, on Mar. 12, 2002.
BACKGROUND OF THE INVENTION
The present invention generally relates to the dispensing of filtered, bottled water. More specifically, the invention relates to a shutoff device that monitors the number of bottles used and then disables further use of the filter when the filter has reached the end of its useful life. The device can also provide an early warning signal to the user that the filter is nearing the end of its useful life.
Self-contained filters for removing unwanted minerals and chemicals such as chlorine have become increasingly popular with bottled water users. These filters may be threadably attached or otherwise connected to the opening of a bottled water container, or may be contained within the water dispenser unit. Various devices are also known for monitoring water flow and then interrupting water flow after a predetermined use.
Some prior art devices have provided techniques for opening a pressure vessel containing a carbon filter used in water purification. However, such techniques are cumbersome and undesirable for the user. Thus, it is desirable to provide an economical self-contained dispenser shutoff and filter cartridge which may be easily replaced when a monitor indicates that the filter has reached the end of its useful life.
In general, prior art patents and known water dispensing disabling devices (herein termed “shutoff devices”) with a filter have tended to concentrate on ways of interrupting water flow through the bottle opening once the filter has reached the end of its useful life, by physically blocking water flow. However, this may result in an interruption in dispensing when the water container still has a substantial volume of water in it, which is not desirable from a user viewpoint. To overcome this problem, some prior art devices provide specific shutoff mechanisms so that when the filter cartridge is removed, dispensing is stopped; these devices also require a separate filter monitor device to visually or audibly warn the user that the filter has reached the end of its useful life. Many such shutoff devices have also tended to have a number of moving parts, increasing the risk of part malfunction.
However, there is a need for a water filter shutoff device which monitors water usage and automatically disables dispensing when the filter has reached the end of its useful life, without the need to rely on visual or audible warning signals. Such a filter shutoff device would also preferably meet the following constraints. Given space constraints, the shutoff device preferably is integral with the filter, and should not unduly impede flow through the filter. The shutoff device would also preferably allow presetting at the time of manufacture to change the allowable water flow or application uses, so that the device could be used with differently rated filters and differently sized water containers. The device should be economical to manufacture and preferably not require an entirely new mold or any substantial additional investment in assembly equipment or fixtures, while also being relatively simple in design with few moving parts to reduce quality control risks. The shutoff device would also preferably disable dispensing, without interrupting water flow from the currently used water container, when a monitor indicates the useful life of the filter is over.
A filter shutoff device preferably meets NSF criteria, including qualifying as a filter “performance indication device” (PID) under NSF standards, and include component materials that have existing NSF approval for extraction. If no filter monitor/PID is provided for a water dispenser with a filter, obtaining NSF approval currently requires that the filter be tested to work at 200% of its rated capacity. If a PID is provided, the filter need only be tested to work at 120% of its rated capacity for NSF approval. For example, if a filter is rated for 150 gallons, and a filter PID is provided, the filter need only have a capacity of 180 gallons, as opposed to 300 gallons if no filter PID is provided. This is a significant added cost feature for a filter manufacturer, since providing a filter capable of filtering 300 gallons requires additional media content resulting in a significant added cost.
Filter shutoff devices must also be provided with venting in some manner to allow continuous water flow, without “lock up”. One problem with such devices is that, upon initial use, as water from the inverted water bottle flows into the device, water pressure/water hammer conditions may cause unfiltered water to leak or spurt out of the venting channels and into the dispensing unit. A sufficient volume of water may escape filtration in this manner, such that the device may not receive NSF approval for, e.g., lead testing. It is also desirable to provide a filter shutoff device which overcomes this problem.
Accordingly, an object of the present invention is to provide a shutoff device integral with a filter and useable with a water dispenser, in which the water dispenser is automatically disabled at the end of the useful life of the filter.
Another object of the invention is to provide a filter shutoff device which does not impede or interrupt water flow between the water dispensing device and a water source such as an inverted water bottle. A further object is to provide such a device that qualifies as filter PID under NSF standards, enabling the more economical manufacture of the filter.
Yet another object is to provide a filter shutoff device which may be manufactured in an economical manner, such that the device monitors the number of water containers used, disables further dispensing after a predetermined number of uses, and then may be discarded and replaced with a new device.
A further object is to provide a filter shutoff device which automatically disables the connection between the device and a water container, rather than simply providing a visual indication of end of filter life, and rather than maintaining the ability to make this connection and physically impeding or interrupting water flow.
A still further object is to provide such a device with an appropriate size and configuration, together with appropriately located and sized vent holes, to ensure that unfiltered water does not leak out of the device and be dispensed.
DEFINITION OF CLAIM TERMS
The following terms are used in the claims of the patent as filed and are intended to have their broadest meaning consistent with the requirements of law. Where alternative meanings are possible, the broadest meaning is intended. All words used in the claims are intended to be used in the normal, customary usage of grammar and the English language.
“Automatic filter shutoff device” means a device in fluid communication with a water container which filters water and then interferes with the ability to dispense water from the container after a predetermined amount of water usage (i.e., the “shutoff” feature), which may generally correspond to the useable life of the filter, has been reached. “Automatic” in this context means that shutoff occurs without the need for user intervention, such as without the need for the user to respond to a visual or audible signal from a filter monitor.
“Monitoring and disabling mechanism” means a mechanism which monitors filter life by monitoring water usage, and which includes a shutoff feature.
SUMMARY OF THE INVENTION
The objects mentioned above, as well as other objects, are solved by the present invention, which overcomes disadvantages of prior filter shutoff devices for water dispensers, while providing new advantages not believed associated with such devices.
In one preferred embodiment, An automatic filter shutoff device is provided, and is removably connected to a water container and in fluid communication with a water dispenser. The device is adapted to monitor water dispensing and disable dispensing after a predetermined amount of water usage. The device includes a housing containing a water filter and removably connected to the water container; and a monitoring and disabling mechanism having a shutoff apparatus moveable between first and second locations, the first location being one in which water dispensing is monitored by the mechanism, and the second location being one in which the mechanism is placed in an interfering position with the connection between the housing and the water container. The shutoff apparatus automatically moves into the second location after the predetermined amount of water usage has occurred, and without interrupting water dispensing from the then-connected water container, so that the used filter shutoff device must be replaced in order to reestablish connection to a successive water container. Preferably, the predetermined amount of water usage generally corresponds to the useable life of the filter.
In a preferred embodiment, the filter shutoff device is adjustable so that dispensing may be disabled after differing amounts of water usage. In one preferred embodiment, the shutoff apparatus includes a plunger whose vertical height may be varied, and the second location is one in which the plunger obstructs the connection of the filter housing and the water container. The monitoring and disabling mechanism may include a filter cap with a downwardly depending leg having a locking window engageable with a locking tab located on the shutoff apparatus. The engaging surfaces of the locking tab and locking window may be angled to facilitate entry of the tab within the window, and to prevent disengagement of the tab and window.
In a particularly preferred embodiment, the plunger has a top surface with a throat opening and annular side walls with spaced openings, and wherein the surface area of the orifice is approximately equal to the surface area of the side openings.
The monitoring and disabling mechanism may include a filter cap mounting radially disposed, opposing teeth, and the shutoff apparatus may include a rotary indexer having a radially protruding tab iteratively communicating with the teeth. In this embodiment, the rotary indexer monitors water dispensing by tracking the number of water containers used during dispensing Preferably, the monitoring and disabling mechanism is a NSF-compliant performance indication device.
A visual indicator, such as a color band located on an outer surface of the filtering and disabling mechanism, may be provided to warn the user that the filter is nearing the end of its useful life. The monitoring and disabling mechanism may also include a visual indication to facilitate adjusting of the mechanism for differing water usages.
In an alternative embodiment, the monitoring and disabling mechanism may include a helical-shaped spring, and a rotary index engageable with teeth having a number corresponding to the predetermined amount of water usage.
In another aspect of the invention, a filter mechanism is provided which is connected to a bottled water container and adapted to be inverted and placed in fluid communication with a water dispenser. The filter mechanism includes a housing containing a water filter with a throat removably connected to the bottled water container. The throat is a restricted orifice sized, such as less than one inch or about ¾-inches in diameter, for example, to permit a volumetric flow rate of not greater than about 7,500 ml./min. of water passage during inversion of the water container and initial flow from the container into the filter. A plurality of vent holes located in an upper surface of the filter housing are provided; the vent holes are sized to permit air from the filter to escape into the water container and allow continuous water flow from the container into the filter. When a new water container is connected to the housing, the water level within the filter does not reach the vent holes in the filter housing. This embodiment may, but need not, including a monitoring and disabling mechanism having a shutoff apparatus as described above.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features which are characteristic of the invention are set forth in the appended claims. The invention itself, however, together with further objects and attendant advantages thereof, will be best understood by reference to the following description taken in connection with the accompanying drawings. The drawings illustrate one preferred embodiment of the present invention. As further explained below, it will be understood that other embodiments, not shown in the drawings, also fall within the spirit and scope of the invention.
FIG. 1 is a perspective view of a water bottle being filled, together with one preferred embodiment of a filter shutoff device according to the present invention;
FIG. 2 is a perspective view showing the threaded connection of a preferred embodiment of the filter shutoff device according to the present invention to a water bottle;
FIG. 3 is a perspective view showing the filter shutoff device, now attached to the water bottle, just prior to seating onto the upper housing of a water dispenser;
FIG. 4 is a perspective view showing various components of a preferred filter shutoff device according to the present invention;
FIG. 5 is a perspective view of the preferred, assembled filter shutoff device;
FIG. 6 is a top view of FIG. 5;
FIG. 7 is a sectional view along reference line 7 — 7 of FIG. 6;
FIG. 8 is a side and planar perspective view of a preferred form of the plunger component of the filter shutoff device;
FIG. 9 is a side and planar perspective view of the plunger and a partial cross-sectional view of the filter cap;:
FIG. 10 is a side and planar partial, cross-sectional view of the plunger and filter cap;
FIG. 11 is a side and planar partial, cross-sectional view of the plunger, filter cap and filter housing;
FIG. 12 is a side and planar perspective view of the plunger, filter cap, spring and filter housing;
FIG. 13 is a side and bottom perspective view of the lower portions of the plunger and filter cap;
FIG. 14 is an exploded view of the area circled “ 14 ” in FIG. 13;
FIG. 15 is a side cross-sectional view of the preferred assembled filter shutoff device;
FIG. 16 is an exploded view of the locking mechanism of the preferred filter shutoff device;
FIG. 17 is a side cross-sectional view of an alternative embodiment of the filter shutoff device of the present invention;
FIGS. 18 and 19 are partial, side cross-sectional views showing two positions of the locking mechanism of an alternative filter shutoff embodiment;
FIG. 20 is a side and planar cross-sectional view of the alternative filter shutoff embodiment of FIG. 17;
FIG. 21 is a side and planar perspective view of the monitoring and shutoff components of the alternative filter shutoff device of FIG. 17;
FIG. 22 is a side and planar perspective view of the assembled components shown in FIG. 21;
FIGS. 23-25 are side; enlarged views of the FIG. 17 embodiment showing opposed teeth and their interaction with a tab of the alternative filter shutoff device;
FIG. 26 is a partial side and cross-sectional view of an alternative, one-piece embodiment of the filter shutoff device of the present invention;
FIG. 27 is a partial sectional,view along reference line 27 / 27 of FIGURE 26;
FIG. 28 is a sectional view along reference line 28 / 28 of FIG. 26; and
FIG. 29 is an exploded view of a portion of filter cap 80 of FIG. 10 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Set forth below is a description of what are currently believed to be the preferred embodiments and/or best examples of the invention claimed. Future and present alternatives and modifications to these preferred embodiments are contemplated. Any alternatives or modifications which make insubstantial changes in function, in purpose, in structure or in result are intended to be covered by the claims of this patent.
Referring first to FIGS. 1-3, a water container such as water bottle 20 is shown, together with a preferred embodiment of the filter shutoff device of the present invention, generally referred to as 30 . While it is preferred that water bottle 20 have threads 35 that allow threaded connection with mating threads 25 on the neck of water bottle 20 , a threaded connection is not required.
Referring to FIG. 3, filter shutoff device 30 is sized and shaped to permit its placement within opening 27 of water cooler housing 26 . (The particular water dispenser chosen for use is of little importance to the present invention.) For this purpose, filter device 30 may include an enlarged rim or neck 37 that rests on the top peripheral wall 27 a of aperture 27 .
Referring now to FIGS. 4-6, one preferred embodiment of filter device 30 includes the following components: filter cap 80 ; plunger 90 ; spring 57 ; support or media retaining ring 33 ; and upper and lower filter pads 32 a , 32 b . Upper pad 32 a is preferably sonic-welded to ring 33 , inside rim 33 a ; lower pad 32 b is preferably sonic-welded to the lower interior of filter housing 36 . Pads 32 a , 32 b maintain the filter media, such as activated charcoal 64 , in place within filter housing 36 . During assembly, plunger 90 is placed down through within center opening 92 a of plunger 90 . Spring 57 compresses against plunger 90 and, in turn, is compressed by retaining ring 33 ; compression is maintained on plunger 90 for the reasons described below. Filter cap 80 may be sonic-welded to the upper surface of filter housing 36 since, in the preferred embodiment, filter shutoff 30 is designed to be replaced, rather than cleaned and re-used, when the useful life of the filter is over. Filter housing 36 is preferably generally cylindrical in shape, as shown, and includes passages 38 (FIG. 11) in its lower surface which permit water passage through the lower end of filter housing 36 . Ribs 113 on the outer surface of housing 36 facilitate gripping of the housing by the user. Filter cap 80 includes vent holes 120 which, in the preferred embodiment shown, are six in number.
Referring to FIG. 8, a preferred from of plunger 90 includes an annular top surface 92 with a restricted throat opening 92 a . Legs 93 project downwardly from top surface 92 and include projections 93 b and retaining tabs 93 a . Annular wall 91 and legs 93 are separated by arcuate openings such as U-shaped openings, as shown.
Referring to FIGS. 7 and 10, filter cap 80 has an inner annular wall 83 with internal threads 35 . Annular wall 83 houses an opposing series of angled teeth, lower teeth 81 and upper teeth 82 . Prior to installation of a water bottle, projection 93 b of plunger 90 is in an upper position in between upper teeth 82 . Upon installation of water bottle 20 , projection 93 b will move straight down about ¼ inch (equal to the distance that the lower edge of the water bottle must travel to meet the filter cap threads 35 ) until projection 93 b lies between two lower teeth 81 . As the water bottle is threaded onto the filter cap, projection 93 b will continue to move downward between the two lower teeth 81 . Referring to FIG. 29, projection 93 b preferably traverses the path shown by circuit 188 .
Filter cap 80 and plunger 90 are preferably designed such that projection 93 b does not touch either the upper surface 82 a of upper teeth 82 or the lower surface 81 b of lower teeth 81 (see FIG. 10 ), so that projection 93 b is not stressed during use. While other dimensions may obviously be used, in a preferred embodiment upper teeth may have a length equal to the length of projection 93 b teeth 81 . For example, in the preferred embodiment, the shorter and longer sides of upper teeth 82 may have a length of 0.062 and 0.109 inches, respectively, while the shorter and longer sides of lower teeth 81 may have a length of 0.253 and 0.294 inches, respectively. (The individual teeth may vary slightly in length, given the individual sections of the collapsible cored use to mold the filter cap.) By designing the filter cap so that the lower teeth 81 are longer than the upper teeth 82 , this ensures that follower projection 93 b will index over and into position so that when threading the filter cap onto the bottle, projection 93 b will continue down the correct channel between the lower teeth, and avoid backtracking of projection 93 b due to clockwise rotation of the threading action.
In operation, and referring now to FIGS. 7-16, plunger 90 rotates as filter shutoff device 30 is replaced and connected to new water bottles. Plunger rotation is caused by the interaction of projection 93 b with opposing angled teeth 81 , 82 . During normal water dispensing and filter use, plunger 90 is positioned at a vertical level that permits threaded connection of threads 35 of filter cap 80 with threads 25 on the neck of bottle 20 (FIG. 2 ). Plunger 90 is maintained by spring 57 in the highest vertical position permitted. As plunger 90 incrementally rotates during the successive use of water bottles, projection 93 b moves within opposing teeth 81 , 82 , which are off-set and angled to induce this rotation. (This continues until retaining tab 93 a reaches locking window 84 . Upon locking, which is further discussed below, plunger 90 is locked at a vertical level such that the plunger covers threads 35 and interferes with engagement of the threads by a water bottle.
Referring to FIGS. 13-16, “lead-in” angled surfaces 93 a 1 , and 84 a of retaining tab 93 a and locking window 84 , respectively, are provided. These surfaces are angled to allow the locking tab to cam its way onto the inside surfaces of window “frame” 84 a as a result of the rotation of plunger 90 during the last few iterative movements of projection 93 b between teeth 81 82 , just prior to the locking of tab 93 within window 84 . This camming action flexes leg 93 toward the filter throat until retaining tab 93 a clears ramped surface 84 a and enters the window itself.
The locking mechanism is also designed to reduce the risk of losing the locking function, as now described. Referring to FIG. 16, if the user tries to connect the bottle threads to filter shutoff device 30 after the locking mechanism has been engaged (and, thus, retaining tab 93 a lies within locking window 84 ), a downward force is exerted on plunger 90 by the water bottle end. This pushes retaining tab 93 a against the bottom surface 84 b of locking window 84 . Bottom surface 84 b and the adjacent bottom surface of locking tab 93 a are each angled slightly in a downward direction moving away from filter throat 91 a . This results in locking tab 93 a having a tendency to “bury” itself deeper into locking window 84 , rather than trying to slide back toward the filter throat and losing engagement with the locking window.
Referring to FIGS. 9 and 11, opening 85 is provided as a relief, to ensure that projections 93 b on the plunger do not shear off as the plunger is installed in addition, opening 85 provides a visual indication to the installer, giving the installer the ability to choose the number of iterations necessary before lock-up of the filter occurs. For example, in the device shown in FIG. 11, fifty teeth 81 , 82 and three openings 85 are provided about the inner circumference of cap 80 . The positions of openings 85 allow a design in which, by initially locating the plunger so that projection 93 b is situated in an opening 85 , filter shutoff device 30 can be configured to provide any number of iterations necessary to correlate the volume of bottles being used and the filter rating, and trigger filter lock-up.
The openings of plunger 90 should be appropriately sized, as now described. First, plunger top 92 is preferably provided with a restricted circular throat 92 a , to reduce water hammer through the plunger. In the preferred embodiment, this opening has a diameter of about ¾ inches, which is 0.442 in 2 . Once the opening in plunger top 92 is sized, the vertical slots in apron 91 of plunger 90 are then sized, by providing slots having an area such that the effective surface area of the openings permitting water travel out the side annular walls of plunger 90 is equal to the surface area of throat opening 92 a in plunger top surface 92 .
Given this preferred plunger size and configuration, it was found that water will fill the upper chamber of the filter, i.e., above media retaining ring 33 and below cap 80 , relatively slowly, such that water will not be permitted to pass through vent holes 120 .
In a particularly preferred embodiment, an early warning signal may be used to notify the user of the impending end of the filter's useful life. For example, a red flag may be sprung into position within the center of the filter when 90% of the filter's useful life has expired. As another example, bi-colored icons or a graduated bi-color band 191 (FIG. 12) may be used to indicate that the useful life of the filter is nearing an end, by matching dot or projection 190 on rotating plunger top surface 92 , for example, with band 191 .
Filter cap 80 carrying opposed teeth 81 , 82 may be manufactured by machining a collapsible core, such as those available from Detroit Mold Engineering of Detroit, owned by Cincinnati Millicron (Catalog No. CC-402-PC). When designing the teeth, a proper draft angle is required to insure release from the molding surface. Each of the teeth has a different shape depending on where they are located on the collapsing core. The collapsing action of the DME core is inward, or perpendicular to the primary draw angle of the mold, and works with a specific number of pie shaped segments, as. disclosed in U.S. Pat. Nos. 3,247,548 and 3,660,001, incorporated herein by reference. These pie shapes, usually consisting of twelve segments, may have two different sizes, e.g., six large and six small. Each segment should be machined separately.
Another aspect of the invention concerning vent holes 120 is now discussed. Referring to FIG. 3, when water bottle 20 is inverted into a dispensing position, a seal is created between shutoff filter rim 37 and bottle seat ledge 27 a . To allow continuous dispensing without lock-up, air passes from outside the filter through vent holes 120 in filter cap 80 (FIG. 6 ), and into water bottle 20 . When the filter is initially installed on the bottle and the bottle is rotated into the functioning position, during the time that water flows down and wets and fills the filter media, the water flow path that presents the least amount of resistance, and thus the path the water actually travels, is through the vent holes. This is believed due to a water hammer effect such that the existing air already in the filter will tend to escape through these vent holes, carrying water with it. This initial condition may result in some (less than about 1 cc.) untreated water escaping through the vent holes and into the treated water. This initial condition may result in a failure to comply with NSF regulations regarding lead treatment, for example.
To solve this problem, a reduced throat diameter “D” (FIG. 6) is provided, e.g., the throat diameter was reduced from about 2 inches to about ¾ inches, for example. In the preferred embodiment, six vent holes 120 are provided on the upper surface of filter cap 80 , and pass completely through the filter cap. One preferred size of the vent holes is about 0.031 inches; however the vent holes may be sized larger, in which case fewer than six may be used. Vent holes 120 permit air to escape from the filter, and flow between the bottle threads and into the water bottle. Using this restricted throat diameter, when water bottle 20 is inverted, water slowly passes into filter shutoff device 30 , such that the water level in the device slowly rises. In a particularly preferred embodiment, 0.7266. minutes was required for 3500 ml. of water to, flow through a filter shutoff device having a throat diameter of about ¾ inches (a fill rate of 4,817 ml./min), whereas only 0.1728 minutes was required for the same volume of water to flow through an identical filter with a throat diameter of about 1.5 inches (a fill rate of 20,255 ml./min). It was noted that water hammer continued to cause water passage through the vent holes until the fill rate was reduced below about 7,500 ml./min. Unlike prior art designs, even during the filling stage and before the water reaches its final level within the filter due to the pressure head created by the bottle neck, the water level never reaches above the level of vent holes 120 . With this design, then, water never flows out through the vent holes, allowing NSF compliance, and reducing spillage and mess.
Referring now to FIGS. 17-25, an alternative embodiment of the filter shutoff device of the present invention, generally referred to as 130 , is shown. Referring first to FIG. 17, filter cap 180 has opposed vertical walls 139 ending in tabs 139 a designed to removably snap into the Opening formed by rim 141 a of ring 141 . The outside walls 141 b of ring 141 preferably taper, as shown, to make room for this removable snap fit. A filter, not shown, is contained within opening 152 created by this connection
Referring still to FIGS. 17-25, filter cap 180 is assembled to a monitoring and locking device, generally referred to as 140 , which consists of rotary indexing ring 141 and stationary ring 143 . Ring 141 includes a number of teeth 144 a axially spaced about the upper internal periphery of the ring, and a flexible or spring-loaded tab 145 positioned along the outside edge of ring 141 , having a distal end 145 a and a function described further below. Ring 143 includes a curved annular disc 144 with two-curved springs 146 , which may be helically-shaped, opposing tabs 148 on the ring periphery, and two opposed indexing tabs 147 . Indexing tabs 147 each have triangular projections 147 a , 147 b , preferably shaped as shown.
Referring now to FIGS. 23-25, during normal water dispensing and operation of the filter, teeth 144 a are positioned as shown in FIG. 23 . Each time filter shutoff device 130 is removed from an empty water bottle 20 and threaded to a new water bottle, device 140 is shaped, sized and configured to provide an rotary indexing movement such that tab 147 is advanced in a counter-clockwise direction (as seen when looking downward on device 130 ) the distance of one tooth, as now explained. Each time device 130 is removed from an empty water bottle, ring 143 is forced upward by springs 146 , causing two adjacent teeth 144 a to be positioned adjacent triangular projection 147 b , as shown in FIG. 24 . The interaction of the leading tooth 144 a 1 , against projection 147 b causes an incremental counter-clockwise rotation of ring 144 and indexing tab 147 (when viewing device 130 from a downward direction). Then, when a new water bottle is threadably attached to device, 130 , ring 143 is forced in a downward direction by the neck of the bottle. When this occurs, indexing tab 147 b moves downward as well so that leading tooth 144 a 1 , now contacts projection 147 a , causing another incremental counter-clockwise rotation of ring 144 and indexing tab 147 , as shown in FIG. 25, such that trailing tooth 144 a 2 is in the position that leading tooth 144 a 1 , of FIG. 23 previously occupied.
In this manner, ring 143 is continued to be advanced in a rotary direction until the disassembly of device 130 from an empty water bottle causes spring-loaded tab 145 to reach opening 150 in vertical wall 139 of filter cap 180 . Now, distal edge 145 a , which was earlier prevented from doing so (see FIG. 18 ), enters opening 150 and halts further rotary movement of ring 143 and indexing tab 147 , as shown in FIGS. 19-20. When this occurs, device 130 can no longer be threadably connected to a new water bottle since the presence of distal end 145 a within opening 150 prevents downward movement of ring 143 , so that ring 143 remains in a position that covers internal threads 135 of filter cap 180 , as shown in FIG. 20 .
As will now be understood, the components of filter monitoring and locking device 140 may be shaped and oriented such that the number of teeth used corresponds to the number of bottles which may be used before the filter is disabled. For example, if 45 teeth are used for 3-gallon bottles, then the filter disable device will activate after 135 gallons of water have been used.
In an alternative preferred embodiment, shown in FIGS. 26-28, filter monitoring and locking device 240 is of one-piece construction, and includes a single molded component consisting of upper ring 243 and lower ring 241 . Indexing tab 247 extends down from ring 244 and includes an upper opening 247 c with a pointed tab 245 . Indexing tab 247 also includes a lower, stepped series of openings 247 d. In a similar manner as described above, ring 243 and tab 247 are rotary indexed in a counter-clockwise direction (again, when viewing device 240 from above) by the stepped orientation and interaction of openings 247 d with teeth 244 a , as shown in FIGS. 26 and 28. As the filter shutoff device is used, removed and then connected to a new water container, tab 247 rotates and pointed tab 245 moves within succeeding angled openings 260 . When tab 247 reaches a position permitting the entry of tab 245 into opening 270 on ring 241 (FIG. 27 ), further rotary movement of ring 243 ceases, disabling the filter shutoff-device by preventing its threaded connection with water container 20 .
It will be understood that the filter shutoff device of the present invention may be used with water containers other than the inverted water bottles shown in the drawings. For example, the device may be used with water pitchers or sports bottles. It will also be understood that the filter shutoff device may be used with a variety of water dispensing devices, and a variety of filters, other than those specifically described here.
While the invention has been described with reference to a threaded connection between filter shutoff device 30 and water bottle 20 , it will be understood that device 30 may be modified for use with water containers that are not intended to be threadably connected to device 30 . For example, filter shutoff device 30 could be used with non-threaded connections between device 30 and water bottle 20 such as those described in U.S. Pat. Nos. 5,222,531 and 5,289,855, incorporated herein by reference, such that a cap could be press-fit onto the filter device. As another example, instead of both the water container and the filter shutoff device having threads, one could have a partial thread and the other a simple projection that would engage the partial thread when the filter shutoff device is rotated; this could act as a helical ramp for the projection, pulling the two components tightly together.
The above description is not intended to limit the meaning of the words used in the following claims that define the invention. Rather, it is contemplated that future modifications in structure, function or result will exist that are not substantial changes and that all such insubstantial changes are intended to be covered by the claims. | An automatic filter shutoff device containing a filter, removably connected to a water container and in fluid communication with a water dispenser, the device monitors water dispensing and disables dispensing after a predetermined amount of water usage. The monitoring and disabling mechanism has a shutoff moveable between dispensing and disabling locations. The disabling location being one in which the mechanism is placed in an interfering position with the connection between the device and the water container. The mechanism automatically moves into the disabling location after the predetermined amount of water usage has occurred without interrupting water dispensing from the then connected water container. This requires that the used filter shutoff device be replaced in order to reestablish connection to a successive water container. | 2 |
This application is a continuation of U.S. application Ser. No. 08/021,120, filed Feb. 23, 1993, now abandoned.
FIELD OF THE PRESENT INVENTION
The invention relates to a chemically adsorbed film and method of manufacturing the same; more particularly, the invention relates to a chemically adsorbed film and its method of manufacture, in which the molecules are, as a whole, densely connected to the substrate surface by chemically bonding graft molecules to chemically adsorbed stem molecules.
BACKGROUND OF THE INVENTION
Conventional methods used for manufacturing chemically adsorbed film include the procedure mentioned, for example, on page 92, volume 102 of the Journal of American Chemical Society (J. Sagiv et al., Journal of American Chemical Society, 92, 102 (1980)) and page 851 of the sixth volume of Langmuir (K. Ogawa et al., Langmuir, 6, 851 (1990)). In this method, a chemically adsorbed film is manufactured by a dehydrochlorination reaction between groups exposed on a substrate surface, such as dehydroxyl groups, and a chlorosilane-based surface active material. The adsorption reaction is carried out for many hours until it reaches the point of saturation adsorption. To form one chemically adsorbed film, an adsorption reaction, a washing and a rinsing are performed once.
However, the above-noted method is limited in improving film density; the number of functional groups of the group itself sets an upper limit on the site number for the adsorption reaction of chemically adsorbed material. As a result, based on the above-noted method, there is a problem that film density can not be improved even by significantly lengthening the time for adsorption reaction.
The method of building up chemical admolecules on a chemically adsorbed film U.S. Pat. Nos. 4,037,474 and 4,992,300 is also known as a conventional method. However, it is difficult to increase the density of molecules on the substrate surface using this method.
SUMMARY OF THE INVENTION
An objective of the invention is to provide a chemically adsorbed film with improved film density, while detailing its method of manufacture, thereby solving the above-noted problems.
To accomplish the above objective, the chemically adsorbed film of this invention is formed by a direct or indirect covalent bonding of stem molecules to the substrate surface via at least one element chosen from Si, Ge, Sn, Ti, Zr, S or C. Graft molecules are covalently bonded to at least one element chosen from Si, Ge, Ti, Zr, S or C via at least one bond chosen from —SiO—, —GeO—, —SnO—, TiO—, ZrO—, —SO 2 —, —SO— and —C—.
In the above-noted composition, it is preferable that direct or indirect covalent bonding between stem molecules and the substrate surface employs at least one bond chosen from the following: —SiO—, —SiN—, —GeO—, —GeN—, —SnO—, —SnN—, —TiO—, —TiN—, —ZrO— and —ZrN—.
In the above-noted composition, it is preferable that a stem or graft molecule contains a hydrocarbon chain, a fluorocarbon chain, an aromatic group or a heterocyclic group.
In the above-noted composition, it is preferable that an unsaturated bond is included in a stem or graft molecule.
In the above-noted composition, it is preferable that a chemically adsorbed film is a monomolecular chemically adsorbed built-up film.
The method of manufacturing a chemically adsorbed film of the invention, which is the method of bonding graft molecules to stem molecules, comprises the following procedures:
(1) directly or indirectly contacting the chemical admolecules, containing functional groups as shown in formula [A] or formula [B] at the end of molecules, with the substrate surface, which either has or is given an active hydrogen or alkali metal on the surface, thereby covalently bonding the chemical admolecules, stem molecules, to the substrate surface by condensation reaction;
removing unreacted chemical admolecules;
reacting the substrate surface with water, thereby substituting the halogen or alkoxyl group, or both, to a hydroxyl group.
Formula [A] is provided as seen below:
—AXm
where X represents halogen, A represents Si, Ge, Sn, Ti, Zr, S or C, m represents 2 or 3.
Formula [B] is represented by:
—A(Q)m
where Q represents an alkoxyl group, A represents Si, Ge, Sn, Ti, Zr, S or C, m represents 2 or 3.
The method additionally comprises contacting the substrate surface with chemical admolecules containing at least one functional group at the end of molecules, chosen from formulas [C] through [G], thereby creating a condensation reaction;
removing unreacted chemical admolecules;
reacting the substrate surface with water.
Formula [C] is designated:
—AXn
where X represents halogen, A represents Si, Ge, Sn, Ti, Zr, S or C, n represents 1, 2 or 3.
Formula [D] is designated:
—A(Q)n
where Q represents an alkosyl group, A represents Si, Ge, Sn, Ti, Zr, S or C, n represents 1, 2 or 3.
Formula [E] is designated:
—SO 2 X
where X represents halogen.
Formula [F] is represented by:
—SOX
where X represents halogen.
Formula [G] is denoted by:
>N—CHO or —OCHO
In the above-noted composition, it is preferable that unreacted chemical admolecules are removed by a nonaqueous solution.
In the above-noted composition, it is preferable that either liquid water or steam is used in the process of reacting stem or graft molecules with water.
In the above-noted composition, it is preferable that the chemical adsorbent, which contains trichlorosilane-based ends, is used as stem or graft molecules.
In the above-noted composition, it is preferable that the condensation reaction due to the contact with stem or graft molecules is a dehydrochlorination, alcohol elimination or water elimination reaction.
In the above-noted composition, it is preferable that a hydrocarbon chain, a fluorocarbon chain, an aromatic group or a heterocyclic group is included in stem or graft molecules.
In the above-noted composition, it is preferable that an unsaturated bond is included in stem or graft molecules.
Based o n this invention, the density of a chemically adsorbed film is improved by increasing the number of admolecules. More specifically, the numb e r of admolecules can be increased by the rise in the site number, which is promoted by introducing graft molecules to the roots of stem molecules. In addition, it is possible that graft molecules are directly bonded to the substrate.
Based on the preferable composition of the invention, direct or indirect covalent bonding of stem molecules to the substrate surface employs at least one bond chosen from —SiO—, —SiN—, —GeO—, —GeN—, —SnO—, —SnN—, —TiO—, —TiN—, —ZrO— and —ZrN—, thus allowing a molecular adsorption film to become chemically stable.
In a preferable composition of the invention—with an unsaturated bond in the hydrocarbon chain of stem or graft molecules—it is possible to polymerize stem and/or graft molecules or to introduce another molecule after the formation of a chemically adsorbed film. It is preferable that the unsaturated bond is the double bond of carbon-carbon (C≡C), the double bond of carbon-nitrogen (C≡N), the triple bond of carbon-carbon (C≡C), the triple bond o f carbon-nitrogen (C≡N) or the like.
Furthermore, a preferable composition of the invention is a chemically adsorbed film and a monomolecular chemically adsorbed built-up film, whereby a film with increased molecular density is formed.
In the method of manufacturing a chemically adsorbed film of the invention, said film with improved film density efficiently may be formed by increasing the number of admolecules, which is made possible by increasing the site number. Moreover, this method can reduce the reaction time.
According to a preferable composition of the invention, the unreacted chemical admolecules are removed by a nonaqueous solution, and a film with a thickness at an angstrom or nanometer level is uniformly formed over the substrate surface.
In a preferable composition of the invention, stem or graft molecules are reacted with liquid water or steam, a halogen atom can be substituted for a hydroxyl group quite efficiently.
The above-noted method of using the chemical adsorbent with trichlorosilane ends as the stem or graft molecules is quite practical, providing a high adsorption reaction.
A preferable composition of the present invention comprises a condensation reaction due to the contact with stem or graft molecules in a dehydrochlorination, alcohol elimination or water elimination reaction, whereby a high reaction rate is possible.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a model view, enlarged to a molecular level, showing the substrate of one example according to the invention.
FIG. 2 is a model view, enlarged to a molecular level, showing the chemically adsorbed monomolecular film of the example according to the invention.
FIG. 3 is a model view, enlarged to a molecular level, showing another chemically adsorbed monomolecular film of the example according to the invention.
FIG. 4 is a model view, enlarged to a molecular level, showing the chemically adsorbed monomolecular film of another example according to the invention.
FIG. 5 is a model view, enlarged to a molecular level, showing another chemically adsorbed monomolecular film of the example according to the invention.
FIG. 6 is a model view, enlarged to a molecular level, showing the chemically adsorbed monomolecular film of another example according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
The method of manufacturing a chemically adsorbed film of the invention comprises fixing a chemical adsorbent to a substrate and chemically adsorbed film by repeating the alternate process of adsorption reaction and washing. Particularly, even in case the first adsorption reaction process is not completely directed without reaching the stage of unsaturated adsorption, the number of —OH groups is increased. This result is obtained by removing unreacted molecules with a nonaqueous solvent and by washing the substrate, which has only scattered admolecules on its surface, with water. After the second adsorption reaction, more than two admolecules are found where only one admolecule was originally contained. In this process, the distance between admolecules is decreased mutually and uniformly, thereby increasing the film density.
However, if the time spent for the adsorption reaction is too short, the adsorbed molecules will be scattered over the substrate at wide distances from one another. As a result, the admolecules can bend, become parallel to the substrate, or cover the original sites for adsorption. In order to prevent such undesirable results, more than several minutes are required for the adsorption reaction.
Under standard reaction conditions, however, it is quite likely that the reaction rate is too fast to enable control of the time for adsorption reaction. In this case, the association or collision rates between the reactive groups of the chemical adsorbent and the active hydrogen groups of a substrate can be reduced by lowering the temperature of the reaction or the concentration of adsorbent; as a result, the time for the reaction is extended and thus becomes quite manageable.
In this invention, a chemical adsorbent may be provided as recited below:
a molecule in which a halosilyl group as shown in formula [C] is bonded to the end of molecule—containing a hydrocarbon chain, a fluorocarbon chain, an aromatic ring, a heterocyclic ring, metal or the like;
a molecule in which an alkoxysilyl or aldehydesilyl group as shown in formula [D] is bonded to the end of molecule—containing a hydrocarbon chain, a fluorocarbon chain, an aromatic ring, a heterocyclic ring, metal or the like;
a molecule in which at least one functional group chosen from halogenated sulfonyl groups as shown in formulas [E] and [F] and an aldehyde group as shown in formula [G] is bonded to the end of molecules—containing a hydrocarbon chain, a fluorocarbon chain, an aromatic ring, a heterocyclic ring, metal or the like.
However, it is preferable that halosilyl group is either dihalosilyl or trihaloxilyl group. Similarly, alkoxysilyl group should be either dialkoxysilyl or trialkoxysilyl group. In terms of reactivity, Cl is prefered to Br or I as a halogen. However, a similar chemically adsorbed film can be formed even with Br or I.
When the adsorption reaction is carried out more than once, the kind of chemical adsorbent can be changed each time. In spite of the fact that the film density is affected by the change of adsorbent, the density can be controlled in many cases.
The increase or control of film density is applicable not only to the case of forming one film on the substrate but to forming a multilayer film on the existing chemically adsorbed film.
The following can be used as chemical adsorbents in this invention:
(1) trichlorosilane-based surface active materials including
CF 3 (CF 2 ) 7 (CH 2 ) 2 SiCl 3 ,
CF 3 CH 2 O(CH 2 ) 15 SiCl 3 ,
CF 3( CH 2 ) 2 SiS(CH 3 ) 2 (CH 2 ) 15 SiCl 3 ,
CF 3 (CH 2 ) 3 (CH 2 ) 2 Si(CH 3 ) 2 (CH 2 ) 9 SiCl 3 ,
CF 3 (CF 2 ) 7 (CH 2 ) 2 Si(CH 3 ) 2 (CH 2 ) 9 SiCl 3
CF 3 COO(CH 2 ) 15 SiCl 3 , or
CF 3 (CF 2 ) 5 (CH 2 ) 2 SiCl 3
(2) monochlorosilane-based surface active materials, whose lower alkyl groups are substituted, or dichlorosilane-based surface active materials including
CF 3 (CF 2 ) 7 (CH 2 ) 2 SiCl n (CH 3 ) 3 −n′
CF 3 (CF 2 ) 7 (CH 2 ) 2 SiCl(C 2 H 5 ) 3 −n′
CF 3 CH 2 O(CH 2 ) 15 SiCl n (CH 3 ) 3 −n′
CF 3 CH H 2 ) 15 SiCl(C 2 H 5 ) 3 −n′
CF 3 (CH 2 ) 2 Si(CH 3 ) 2 (CH 2 ) 15 SiCl (CH 3 ) 3
CF 3 (CH 2 ) 2 Si(CH 3 ) 2 (CH 2 ) 15 SiCl(C 2 H 5 ) 3 −n′
CF 3 (CF 2 ) 7 (CH 2 ) 2 Si(CH 3 ) 2 (CH 2 ) 9 SiCl(CH 3 ) 3 −n′
CF 3 (CF 2 ) 7 (CH 2 ) 2 Si(CH 3 ) 2 (CH 2 ) 9 SiCl(C 2 H 5 ) 3 −n′
CF 3 COO(CH 2 ) 15 SiCl (CH 3 ) 3 −n′
CF 3 COO(CH 2 ) 15 SiCl (C 2 H 5 ) 3 −n′
CF 3 (CF 2 ) 5 (CH 2 ) 2 SiCl(CH 3 ) 3 −n′ or
CF 3 (CF 2 ) 5 (CH 2 ) 2 SiCl(C 2 H 5 ) 3 −n′
where n represents 1 or 2.
In particular, trichlorosilane-based surface active materials, in which adjacent molecules form siloxane bonds, are preferable for obtaining a stronger chemically adsorbed film.
Moreover, CF 3 (CF 2 )CH 2 CH 2 SiCl 3 (where n represents an integer, preferably between about 3 and 25) is preferable since it is balanced with the dissolution property, chemical adsorption property, water- and oil-repelling property, and anticontamination property or the like. By incorporating an unsaturated bond into an alkyl or alkyl fluoride chain, a bridge formation can be formed by irradiation with an electron beam at only about 5 Mrads, after formation of a chemically adsorbed film; as a result, the hardness of the film can be improved.
Trichlorosilane-based surface active materials, such as the following: CH 3 (CH 2 ) 18 SiCl 3 , CH 3 (CH 2 ) 15 SiCl 3 , CH 3 (CH 2 ) 10 SiCl 3 , CH 3 (CH 2 ) 25 SiCl 3 or the like, and monochlorosilane-based materials, whose lower alkyl groups are substituted, or dichlorosilane-based surface active materials, such as the following: CH 3 (CH 2 ) 18 (CH 3 ) 3 −n CH 3 (CH 2 ) 18 SiCl n(C 2 H 5 ) 3 −n′CH 3 (CH 2 ) 15 (CH 3 ) 3 −n° CH 3 (CH 2 ) 10 (CH 3 ) 3 −n′CH 3 (CH 2 ) 25 SiCl n (C 2 H 5 ) 3 −n or the like, are included as chlorosilane-based surface active materials containing alkyl groups. CH 3 (CH 2 )nSiCl 3 (where n represents an integer, preferably between about 3 and 25) is most preferable among these for the dissolution property of the solvent.
In order to achieve a high adsorption density, a linear chlorosilane-based surface active material is preferred. However, as said active material applied in this invention, the alkyl fluoride or hydrocarbon groups of the material can be diverged, or the silicons at the ends of the material can be substituted by alkyl fluoride or hydrocarbon groups, expressed as the formulas including R 2 SiCl 2 , R 3 SiCl, R 1 R 2 SiCl 2 or R 1 R 2 R 3 SiCl, where R, R 1 , R 2 and R 3 represent alkyl fluoride or hydroxyl groups.
A nonaqueous solvent used for this invention is preferably chosen from the following solvents:
fluoric solvent such as 1, 1-dichloro, 1-fluoroethane; 1, 1-dichloro, 2, 2, 2-trifluoroethane; 1, 1-dichloro, 2, 2, 3, 3,3-pentafluoropropane; 1, 3-dichloro, 1, 1, 2, 2, 3-heptafluoropropane or the like;
hydrocarbon-based solvent such as hexane, octane, hexadecane, cyclohexane or the like;
ethers solvent such as dibutylether, dibenzylether or the like;
esters solvent such as methyl acetate, ethyl acetate, isopropyl acetate, amyl acetate or the like.
Acetone, methyl ethyl ketone or the like can be used as ketone solvent.
Metal such as Al, Cu, stainless steel or the like, glass, ceramics, or a group which is hydrophilic but contains a comparatively small number of hydroxyl groups (—OH)-such as a plastic, whose surface is hydrophilic—are included as groups which can be used for this invention.
In employing metal as said group, it is preferable to use a base metal such as Al, Cu or stainless steel since chemical adsorption is promoted between the hydrophilic groups on the substrate surface and chlorosilyl groups in this invention.
If a material, such as plastic, does not have an oxide film on its surface, the surface must become hydrophilic beforehand by introducing to it carboxyl and hydroxyl groups. The introduction of such groups can be directed by treating the surface with 100W under a plasma atmosphere, containing oxygen, for 20 minutes, or by corona treatment. However, in case of nylon and polyurethane resin, which have imino groups (>NH) on their surfaces, such treatment is not necessary; a dehydrochlorination reaction is promoted between the hydrogens of the imino groups (>NH) of the substrate and the chlorosilyl groups (—SiCl) of a chemical adsorbent, thereby creating a siloxane bond (—SiO—).
This invention can be applicable for various uses and materials as described in the following:
(a) examples of substrates—metal, ceramics, plastic, wood, stone (the invention being applicable even when the substrate surface being coated with paint or the like in advance);
(b) examples of cutlery—kitchen and other knives, scissors, engraver, razor blade, hair clippers, saw, plane, chisel, gimlet, badkin, cutting tools, drill tip, blender blade, juicer blade, flour mill blade, lawn mower blade, punch, straw cutter, stapler, blade for can opener, surgical knife or the like; (c) examples of needles—acupuncture needle, sewing needle, sewing-machine needle, long thick needle for making tatami, syringe needle, surgical needle, safety pin or the like;
(d) examples of products in the pottery industry—products made of pottery, glass, ceramics or enameled products, including hygienic potteries (such as a chamber pot, wash-bowl, bathtub, etc.), tableware (such as a rice bowl, plate, bowl, teacup, glass, bottle, coffee-pot, pots and pans, earthenware mortar, cup, etc.), flower vases (such as a flower bowl, flowerpot, small flower vase, etc.), water tanks (such as a breeding cistern, aquarium water tank, etc.), chemistry apparatus (such as a beaker, reacter vessel, test tube, flask, culture dish, condenser, stirring rod, stirrer, mortar, vat, syringe), roof tile, tile, enameled tableware, enameled wash bowl, and enameled pots and pans;
(e) examples of mirrors—hand mirror, full-length mirror, bathroom mirror, washroom mirror, mirrors for automobile (back and side mirrors), half mirror, mirror for show window, mirrors for department store or the like;
(f) examples of molding parts—die for press molding, die for cast molding, die for injection molding, die for transfer molding, die for vacuum molding, die for blow forming, die for extrusion molding, die for inflation molding, die for fiber spinning, calender processing roll;
(g) examples of ornaments—watch, jewelry, pearl, sapphire, ruby, emerald, garnet, cat's-eye, diamond, topaz, bloodstone, aquamarine, turquoise, agate, marble, amethyst, cameo, opal, crystal, glass, ring, bracelet, brooch, tiepin, earrings, necklace, glasses frames (of platinum, gold, silver, aluminium, titanium, tin, compound metals of these elements, or stainless steel) or the like;
(h) examples of molds for food—cake mold, cookie mold, bread mold, chocolate mold, jelly mold, ice cream mold, oven plate, ice tray or the like;
(i) examples of cookware—pots and pans, iron pot, kettle, pot, frying pan, hot plate, net for grilling food, tool for draining off oil, plate for making takoyaki or the like;
(j) examples of paper—photogravure paper, water and oil repellent paper, paper for posters, high-quality paper for pamphlets or the like;
(k) examples of resin—polyolefin (such as polypropylene, polyethylene, etc.), polyvinylchloride, polyvinylidenechloride, polyamide, polyimide, polyamideimide, polyester, aromatic polyester, polystyrene, polysulfone, polyethersulfone, polyphenylenesulfide, phenolic resin, furan resin, urea resin, epoxide, polyurethane, silicon resin, ABS resin, methacrylic resin, ethylacrylate resin, ester resin, polyacetal, polyphenyleneoxide or the like;
(1) examples of household electric goods—television, radio, tape recorder, audio goods, CD player, refrigerator, freezer, air conditioner, juicer, blender, blade of an electric fan, lighting equipment, dial plate, hair drier for perm or the like;
(m) examples of sporting goods—skis, fishing rod, pole for pole vault, boat, sailboat, jet skis, surfboard, golf ball, bowling ball, fishing line, fishing net, fishing float or the like;
(n) examples of vehicle parts;
(1) ABS resin—lamp cover, instrument panel, trimming parts, and protector for a motorcycle,
(2) cellulose plastic—markings for automobile, and steering wheel,
(3) FRP (Fiber Reinforced Plastics)—bumper, and engine cover,
(4) phenolic resin—brake,
(5) polyacetal—wiper, wiper gear, gas valve, carburetor parts,
(6) polyamide—radiator fan,
(7) polyarylate (polycondensation polymerization by bisphenol A and pseudo phthalic acid)—direction indicator lamp (or lens), cowl board lens, relay case,
(8) polybutylene terephthalate—rear end, front fender,
(9) poly amino-bismaleimide—engine parts, gear box, wheel, suspension drive system,
(10) methacrylate resin—lamp cover lens, meter panel and cover, and center mark,
(11) polypropylene—bumper,
(12) polyphenylene oxide—radiator grill, wheel cap,
(13) polyurethane—bumper, fender, instrument panel, and fan,
(14) unsaturated polyester resin—body, gas tank, heater housing, meter panel,
(o) examples of stationary goods—fountain pen, ballpoint pen, mechanical pencil, pencil case, binder, desk, chair, book shelf, rack, telephone base, ruler, draftsman's outfit or the like;
(p) examples of building materials—roof materials (such as ceramic tile, slate, tin such as used in galvanized iron plate, etc.), outer wall materials (such as wood including processed wood, mortar, concrete, ceramic sizing, metallic sizing, brick, building stone, plastic material, metallic material including aluminium, etc.), interior materials (such as wood including processed wood, metallic material including aluminium, plastic material, paper, fiber, etc.) or the like;
(q) examples of stone materials—granite, marble or the like, used for building, building material, works of art, ornament, bath, gravestone, monument, gatepost, stone wall, sidewalk, paving stone, etc.
(r) examples of musical instruments and audio apparatus—percussion instruments, string instruments, keyboard instruments, woodwind instruments, brass instruments or the like, more specifically, drum, cymbals, violin, cello, guitar, koto, piano, flute, clarinet, shakuhachi, horn, etc., and microphone, speaker, earphone or the like.
(s) others—high voltage insulator with good water, oil and contamination-repelling properties, including thermos bottles, vacuum apparatus, insulator for transmitting electricity, spark plugs or the like.
The method of manufacturing a chemically adsorbed film of the invention will now be explained specifically in the following examples 1-3.
EXAMPLE 1
Adsorption solution A was prepared by dissolving 1% by weight of a chemical adsorbent, n-nonadecyl trichlorosilane, into the mixed solvent of hexadecane, carbon tetrachloride and chloroform at a weight ratio of 80:12:8 respectively.
Glass substrate 1, as a hydrophilic group, was prepared as shown in FIG. 1 . After being washed with a nonorganic solvent, the substrate was dipped in adsorption solution A for five minutes. Due to this treatment, a dehydrochlorination reaction was promoted between the Si—Cl groups of n-nonadecyl trichlorosilane and the —OH groups of glass substrate 1, thereby forming a chemically adsorbed film on the substrate as shown in formula [1].
Formula [1]
A chemically adsorbed monomolecular film 2 as shown in FIG. 2, which had only a few horizontal bonds since the —OH groups were unaffected, was formed after washing the substrate with a nonorganic solvent for 15 minutes and with chloroform for another 15 minutes. This monomolecular film was firmly connected to the substrate, and had excellent water-repelling properties.
The formation of the film was confirmed by obtaining particular signals for this structure at 3680 (reversion: Si—OH), 2930-2840 (reversion: CH 3 , —CH 2 —), 1470 (reversion: —CH 2 —), and 1080 (reversion: Si—O)cm −1 by Fourier Transform Infrared Spectral (FTIR) measurement.
As a next step, a readsorption reaction was directed. The substrate with the formed monomolecular film was dipped and held in a newly prepared adsorption solution A for one hour. The substrate was then washed with a nonorganic solvent for 15 minutes and with water for another 15 minutes, thereby promoting a dehydrochlorination reaction between Si—Cl groups of n-nonadecyl trichlorosilane and —OH groups at the root of monomolecular film 3 . As a result, a chemically adsorbed film was formed on glass substrate 1 as shown in FIG. 3 .
According to FTIR measurement, the particular signals for this structure at 2930-2840 (reversion: CH3, —CH 2 —), 1470 (reversion: —CH 2 —), 1080 (reversion: Si—O)cm −1 were stronger than the signals obtained after the first reaction. This result confirmed the increase of admolecules. The absorption wave number, measuring the asymmetric stretching vibration of methylene, declined from 2929 cm −1 after the first adsorption reaction to 2921cm- −1 after the second reaction. It is generally known that such decline in wave number occurs when the distance between molecules with a long chain alkyl part decreases. In fact, the absorption wave number of certain material decreases as the material changes from a gaseous body to a liquid body and then to a solid body. Therefore, confirmation was obtained that the film density increased due to the decrease in distance between the molecules—the composition of the film—after the readsorption reaction.
EXAMPLE 2
Adsorption solution B was prepared by dissolving 1% by weight of a chemical adsorbent, n-nonadecenyl trichlorosilane, into a mixed solvent of hexadecane, carbon tetrachloride and chloroform at a weight ratio of 80:12:8, respectively. As a hydrophilic group, glass substrate 1 was prepared. After being washed with organic solvent, the substrate was dipped and held in adsorption solution B for five minutes. As a result, a dehydrochlorination reaction was promoted between Si—Cl of n-nonadecenyl trichlorosilane and OH of glass substrate 1 , thereby forming a chemically adsorbed film on the substrate as shown in formula [2].
Formula [2]
After washing the substrate with a nonaqueous solvent chloroform for 15 minutes and with water for another 15 minutes, chemically adsorbed monomolecular film 4 as shown in FIG. 4, which had few horizontal bonds since —OH groups were unaffected, was formed. This monomolecular film was firmly connected to the substrate, and possessed good water-repelling properties.
Signals were obtained for this structure at 2930-2840 (reversion: —CH 2 —), 1470 (reversion: —CH 2 —), 1080 (reversion: Si—O)cm −1 by FTIR measurement, thereby confirming the formation of the film.
A readsorption reaction was directed as in the following procedures:
dipping and holding the substrate formed with the monomolecular film 5 in a newly prepared adsorption solution B;
washing the substrate with a nonaqueous solvent, chloroform for 15 minutes and with water for another 15 minutes.
A dehydrochlorination reaction was then promoted between Si—Cl of n-nonadecyl trichlorosilane and —OH groups of glass substrate 1 , thereby forming a chemically adsorbed film on the substrate as shown in FIG. 5 .
The particular signals obtained by FTIR measurement at 2930-2840 (reversion: —CH 2 —), 1470 (reversion: —CH 2 —), 1080 (reversion: Si—O)cm −1 for this structure were strengthened compared with the signals obtained from the first adsorption reaction, thereby confirming an increase of admolecules. Moreover, the absorption wave number of assymmetric stretching vibration of methylene declined from 2928 cm— −1 after the first adsorption to 2921 cm −1 after the second adsorption.
As in example 1, after the readsorption reaction, the distance between molecules of the film became shorter, and the film density was increased.
EXAMPLE 3
Adsorption solution C was prepared by dissolving 1% by weight of a chemical adsorbent, 14-bromotetradecyl trichlorosilane, into a mixed solvent of hexadecane, carbon tetrachloride and chloroform at a weight ratio of 80:12:8, respectively.
A chemically adsorbed film shown in FIG. 2 was formed through the following procedures as detailed in example 2:
promoting the first adsorption by dipping and holding glass substrate 1 in adsorption solution A;
washing the substrate with a nonaqueous solution, chloroform, and then with water, thereby forming the film. This monomolecular film was firmly fixed to the substrate, and had a good water-repelling property. As in example 1, the formation of the film was confirmed by obtaining particular signals by FTIR measurement.
Readsorption was directed as in the following procedures:
dipping and holding the substrate formed with monomolecular film 2 in a newly prepared adsorption solution C for one hour;
washing the substrate with a nonaqueous solvent, chloroform for 15 minutes and with water for another 15 minutes.
As a result, a dehydrochlorination reaction was promoted between Si—Cl of 14-bromotetradecyl trichlorosilane and OH of glass substrate 1 or at the root of monomolecular film 3 , thereby forming chemically adsorbed film 7 on the substrate as shown in FIG. 6 .
Stronger signals at 2930-2840 (reversion: CH 3 , —CH 2 —), 1470 (reversion: —CH 2 —), 1080 (reversion: Si—O)cm −1 were obtained by FTIR measurement after the second adsorption reaction. The creation of an additional particular signal at 1440 (reversion: Br—C)cm −1 was also confirmed after the second adsorption. Absorption wave number by the asymmetric stretching vibration of methylene declined from 2928 cm −1 after the first adsorption to 2922 cm 1after the second adsorption. As in other examples, it was confirmed that the distance between the molecules became shorter and the film density was increased.
Although a chemical adsorbent containing halosilyl groups was used for examples 1-3, the same results could be obtained by using an adsorbent having alkoxysilyl groups or the like.
For the first adsorption reaction, a chemical adsorbent comprises a functional group shown in formula [A] or formula [B]. From the second repetition onwards, however, a chemical adsorbent contains at least one group chosen from the group consisting of halosilyl, alkoxysilyl or functional groups shown in formulas [A] through [G].
As explained above, a highly dense chemically adsorbed film is formed by repeating an adsorption reaction and washing process, and by covalently bonding a chemical adsorbent to a substrate and a chemically adsorbed film. The density of the adsorbed film, in addition, can be controlled by varying the time for adsorption reaction, the number of repetitions, and the kind and combination of chemical adsorbents.
The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein. | A highly dense chemically adsorbed film is formed by repeating the alternate process of adsorption reaction and washing. Adsorption reaction is directed by contacting the substrate surface, which has or is given an alkali metal or a functional group, with a chemical adsorbent, having halosilyl or alkoxysilyl groups at the end of molecules. An unreacted chemical adsorbent is then washed away from the substrate surface. The alternate treatment of adsorption reaction and washing is repeated, thereby covalently bonding a chemically adsorbed film to the substrate surface. As a result, a chemically adsorbed film is formed in which stem molecules are directly or indirectly covalently bonded to the substrate surface via at least one element chosen from the group consisting of Si, Ge, Sn, Ti, Zr, S or C and graft molecules are covalently bonded to at least one element chosen from Si, Ge, Sn, Ti, Zr, S or C via at least one bond chosen from —SiO—, —GeO—, SnO—, —TiO—, ZrO—, —SO 2 —, —SO— and —C—. | 8 |
FIELD OF THE INVENTION
This invention is a board game wherein the board has the same number of squares as a chess board and each player has sixteen movable pieces, as in chess. The movable pieces are military pieces simulating military personnel, armament, and a headquarters. The rules of chess apply except that the military pieces are enabled to move in a manner simulating movement of military equipment, which enables the players to combine military strategy with chess-like logic.
BACKGROUND OF THE INVENTION
THE GAME OF CHESS
Chess is a game of skill for two players. It is played on a square board divided into sixty four squares arranged in an eight-by-eight matrix, or in eight rows of eight squares each. The rows of squares are called ranks. Columns of squares are called files. The squares are alternately light and dark colors, commonly red and black. Each row has four light and four dark squares, with a light square at one end and a dark square at the other end.
Each chess player has sixteen movable pieces, namely, a king, a queen, two bishops two knights, two rooks or castles, and eight pawns. The movable chess pieces are typically white (or light) and black (or dark), corresponding to the light and dark squares on the board, and are arranged on the two horizontal rows of light and dark squares closest to each player.
Each player places the queen of that player's chosen or assigned color on the square of her own color nearest the center of the row closest to the player. The king is placed next to the queen on the other square nearest the center of the same row. The two bishops are placed on the same row and on the squares next to the king and the queen. The two knights are placed on the same row on the squares next to the bishops and the two rooks are placed at the ends of the same row, beside the knights. The eight pawns are placed on the eight squares of the next row.
According to the rules of chess:
(1) The king moves one square in any direction and can capture any opponent's piece, except the king, by moving into the square occupied by the other piece, except the king cannot move into a square where the king would be vulnerable to capture by an opponent's piece.
(2) The queen moves in a straight line on the rank, the file, or diagonally in any direction and for any distance over unoccupied squares. The queen cannot jump over pieces. The queen captures an opponent's piece, except the king, by moving into the square occupied by that piece.
(3) The bishops move diagonally over unoccupied squares for any distance. Thus, one bishop of each player may only move on dark squares and the other bishop may only move on light squares. Bishops capture an opponent's piece, except the king, by moving into a square occupied by that piece.
(4) The knights move in an L-shaped pattern, two squares in a straight line along a row or file and then one square at a right angle. A knights' move must end on a square the opposite color from the one on which it started. The knight is the only piece that may "jump" other pieces, but the piece over which a knight jumps is not affected by the jump. The knight captures an opponent's piece, except the king, by ending its move on the square occupied by that piece.
(5) The rooks move in a straight line for any distance. The rooks cannot jump or move diagonally. The rooks capture an opponent's piece, except the king, by moving into a square occupied by that piece.
(6) The pawns move one square forward (toward the opponent), except the initial move of each pawn may be either one square or two squares forward. A pawn must move diagonally forward one square to capture an opponent's piece, except the king, occupying that square. The pawn cannot move diagonally except to capture an opponent's piece, If a pawn advances to the eighth rank (the rank at the opposite side of the board), the pawn may be exchanged for a queen, rook, bishop or knight of the same color without regard to the number and type of pieces then on the board.
(7) Each chess player can perform a move called a "castle" once in the game, except when the king is in check, or if there are other pieces between the king and rook, or if the king or rook have been previously moved, or if the king or rook must pass over or land on a square occupied by an opponent's piece. "Castling" transposes a player's king and one rook. The king is moved two squares to its right or left on one row toward one rook and that one rook is moved over the king and placed on the square beside the king in the same row.
A king is "checked" when he is vulnerable to capture by an opponent's piece. The player "checking" an opponent's king must say "check". To avoid "checkmate", and the end of the game, a king in "check" must either move out of check, capture the attacking piece, or the defending player must move another piece between the king in "check" and the attacking piece. If none of those things can be done, then the king is "checkmated" and the game is over.
OTHER PRIOR ART
Games utilizing game boards with alternately colored squares and game pieces simulating military personnel and equipment have long been known.
U.S. Pat. No. 186,181 issued Jan. 9, 1877 to B. F. Underwood for GAME APPARATUS shows a game board with seventy two squares and ten game pieces for each of the two players. The pieces for each player include:
(a) a miniature foot soldier, representing infantry (six pieces),
(b) a miniature horse and rider, representing cavalry (two pieces), and
(c) a miniature cannon, representing artillery (two pieces).
The infantry moves one square in any direction; the cavalry moves three squares in any direct ion; and the artillery moves two squares in straight lines only. One player's pieces are light colored and the other player's pieces are dark colored.
Underwood's game board is different than the chess board and Underwood uses a different number of pieces than are used in chess.
U.S. Pat. No. 2,414,165 issued Jan. 14, 1947 to Guy Paschal for GAME PIECE shows a preferred game board with one hundred twenty one alternately colored squares. Paschal says the game can be played on a standard chess board with sixty four squares, "but the strategy of the game is cramped thereby" (column 6, lines 35, 36). The pieces for each player are miniature replicas of:
(a) an airplane carrier (one piece),
(b) a transport vessel (one piece),
(c) a battleships (one piece),
(d) a destroyer (one piece),
(e) a submarine (one piece),
(f) an airplane (two pieces),
(g) a torpedo (four pieces), and
(h) a shell (five pieces).
The airplane carrier and the battleship are large enough to occupy two squares. The miniature ships are marked to indicate their armament and to indicate their vulnerability to being sunk by an opponent. The rules provide for the movement capabilities of the pieces.
Paschal's game board is preferably different than the chess board, and "the strategy of the game is cramped" if a chess board is used in playing Paschal's game. The rules of Paschal's game, concerning movement of the pieces and the vulnerability and striking power of the miniature ships, are different from and far more complicated than the rules of chess.
U.S. Pat. No. 2,400,644 issued May 21, 1946 to Hoffman for MILITARY CHESS GAME shows a game board with ninety six alternately colored squares, twelve along one side and eight squares along an adjacent side. Eighteen game pieces, miniature replicas of military personnel and equipment, are provided for each of the two players:
(a) infantrymen (eight pieces)
(b) anti-aircraft guns (two pieces)
(c) light tanks (two pieces)
(d) heavy tanks (two pieces)
(e) airplanes (two pieces)
(f) heavy artillery (two pieces)
Hoffman provides a "smokescreen" in the center of the board to prevent opposing players from observing the initial deployment of the enemy forces. The "smokescreen" is removed after the opposing forces have been deployed and the players alternately move their pieces according to the rules of Hoffman's game. The infantry pieces move the same as pawns in chess. All of Hoffman's other pieces move differently than chess pieces.
Hoffman's game board is different from the chess board, and Hoffman uses a different number of pieces than are used in playing chess.
The game chess and the three patents discussed above comprise the known prior art most pertinent to applicant's invention.
SUMMARY OF THE INVENTION
The invention is a game for two players using the same game board and the same number of playing pieces as in chess, but in a military environment on a camouflaged game board with game pieces (military pieces) that are miniature replicas of military personnel and equipment. The rules governing movement of the military pieces enable the players to simulate combat strategies that could be used in an actual ground battle, but cannot be carried out by following the traditional rules of chess.
The distinctive features of this invention combine with the traditional features of chess to enable the players to create unique offensive and defensive scenarios with military pieces that simulate aerial and ground military forces in the environment of a military engagement. Specifically, the rules governing movement of the military pieces enable players of the present game to combine military strategy with chess-like logic.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of the game board, showing the initial position of the military pieces on the board;
FIG. 1A is a designated illustration of each military piece.
FIGS. 2-10 are plan views of the game board, each of which shows one of the military pieces and illustrates its capability of movement; and
FIG. 11 is a plan view of an embodiment of the invention utilizing a numbered game board.
DETAILED DESCRIPTION OF THE INVENTION
The military chess game is played by two players on a conventional chess board (battlefield) 10 with sixty four alternately colored squares. As in chess, the game board 10 has a main playing area defined by a square matrix of eight rows and eight files defining sixty four alternately colored playing squares, preferably dark green squares 11 and light tan squares 12, as in standard camouflage colors.
The object of the game is for each p layer to move the military pieces comprising their respective armies to strategic positions and/or protect their "headquarters" while trying to capture the enemy's military pieces and the enemy "headquarters" until Victory is achieved.
THE ARMIES
Each player initially has an "army" comprising sixteen correspondingly colored military playing pieces, illustrated in FIGS. 1 1 and 1A and comprising:
(a) Six military pieces simulating a combat soldier, designated as "Infantry Forces" and indicated at 13 for the dark "army" and at 13A for the light "army" in FIG. 1. The movement capabilities of the infantry forces are shown FIGS. 2, 4, and 5.
(b) Two military pieces simulating a small tank, designated "Calvary Tank Brigades" and indicated at 14 for the dark army and at 14A for the light army in FIG. 1. The movement capabilities of the cavalry tank brigades are shown in FIGS. 3, 4 and 5.
(c) Two military pieces simulating a large armored tank, designated "Armored Tanks" and indicated at 15 for the dark army and at 15A for the light army in FIG. 1. The movement capabilities of the armored tanks are as shown in FIGS. 4, 5, and 6.
(d) Two military pieces simulating a fighter plane, designated "Fighter Planes" and indicated at 16 for the dark army and at 16A for the light army in FIG. 1. The movement capabilities of the fighter planes are shown in FIG. 7.
(e) Two military pieces simulating a helicopter, designated "Attack Helicopters", and indicated at 17 for the dark army and at 17A for the light army in FIG. 1. The movement capabilities of the helicopters is shown in FIG. 8.
(f) One military piece simulating a bomber, designated "Bomber Plane", and indicated at 20 for the dark army and at and 20A for the light army in FIG. 1. The movement capabilities of the bomber are shown in FIG. 9.
(g) One military piece simulating an army headquarters building, designated "Command Headquarters", and indicated at 21 for the dark army and at 21A for the light army in FIG. 1. The movement capabilities of the command headquarters is shown in FIG. 10.
The players move in alternating turns, as in standard chess, a piece or pieces in continuing efforts to capture enemy pieces while protecting their own. During a move, the moving piece may capture an enemy military piece by moving, in accordance with rules requiring limited movement, as illustrated in FIGS. 2 through 10, to a square occupied by the enemy's piece. The enemy piece is removed and the moving piece occupies that space.
In FIGS. 2 through 10, a single dotted line with arrows illustrates rules requiring limited movement of each military piece. A solid arrowhead indicates moves with or without capturing an enemy piece. A hollow arrowheard indicates moves that can be made only without capturing an enemy piece. The moving piece can only move as shown by the dotted line to the space having the hollow arrowhead if that space is not occupied (FIGS. 2 and 4).
Each player of this military chess game has three military pieces with the same initial positions and subject to the same rules for movement as three of the pieces used by each player in the standard game of chess.
Two of those military pieces are the fighter planes 16 used by one player and the fighter planes 16A used by the other player of this military chess game. The fighter planes 16, 16A are initially positioned on the board like a chess player's knights are positioned on a chess board, and the fighter planes 16, 16A are subject to the same limited movements as are the knights in chess.
The command headquarters 21 of one player of this military chess game and the command headquarters 21A of his opponent represent the other military piece of this military chess game that occupies the same initial position and is subject to the same rules for movement as a chess piece used by each chess player in the standard game of chess. Each command headquarters initially occupies the same position on the game board as does one of the kings on a standard chess board and is subject to the same limited rules for movement as is the king in chess.
The color of the players' armies and the determination of which player moves first is decided by chance, such as the winner of a coin toss or throw of the dice.
The military pieces of each army are initially placed on the game board 10 with the light colored bomber 20A on the light colored square nearest the center of the first row of the light colored army, and with the dark colored bomber 20 starting on the dark colored square nearest the center of the first row of the dark colored army.
According to the rules governing the game of this invention, the infantry forces 13, 13A can move one square at a time, either forwardly or laterally or rearwardly or diagonally (FIG. 2).
The infantry forces 13, 13A can move diagonally one square at a time only if that diagonal square is unoccupied, as shown in FIGS. 4 and 5, but infantry forces 13, 13A do have the ability to participate with other infantry forces of the same color and with like-colored pieces of the cavalry tank brigades 14, 14A and the armored tanks 15 and 15A in blitz movements, as shown in FIGS. 4 and 5. Infantry forces can capture an enemy piece by moving forwardly, laterally, or rearwardly but, as shown in FIG. 2, infantry forces cannot capture an enemy piece by moving diagonally, as do pawns in the game of chess.
According to the rules of this military chess game, a blitz is a surprise coordinated movement by a group of two or more military pieces occupying consecutive squares that form a straight line in any direction. Only those military pieces representing infantry forces, cavalry tank and armored tank are recognized by the rules as having the ability to move together in a blitz that counts as one move.
The rules of the game provide that any piece of an army's infantry force that reaches the enemy's end of the game board can be substituted for any previously captured piece of the same color.
The rules governing the moves of the cavalry tank brigades 14, 14A are like those governing the moves of the infantry forces, with the important exception that the pieces of the cavalry tank brigades can move diagonally to capture an enemy piece, as shown in FIG. 4. Cavalry tank brigades 14 and 14A have the ability to participate with other cavalry tank brigade of the same color and with like-colored pieces of the infantry forces 13 and 13A and the armored tanks 15, 15A in blitz moves, as shown in FIGS. 4 and 5.
The rules governing movement of the armored tanks 15, 15A provide that the armored tanks can move:in any one direction, either forwardly, rearwardly, laterally, or diagonally, over any three unoccupied squares, and that the armored tanks 15, 15A have the ability to participate with other armore tanks of the same color and with like colored pieces of the infantry forces 13 and 13A and the cavalry tank brigades 14, 14A in blitz movements, as shown in FIGS. 4 and 5.
Each player has the option of making a blitz movement of one square in any direction when there is an alignment in any direction of two or more pieces of that player's infantry forces (I.F.), cavalry tank brigade (C.T.), or armored tank (A.T.). According to the game rules, only the front or leading I.F., C.T. or A.T. can capture an enemy piece that occupies the square on which a blitz movement ends.
The rules permit the player to choose how many properly aligned I.F., C.T., and/or A.T. pieces to move during a blitz. According to the rules, the pieces involved in a blitz follow behind a leading I.F., C.T., and/or A.T. The rules permit armored tanks to move in a blitz that moves either forwardly, rearwardly, or laterally, but the armored tanks can move only one square when moving as part of a blitz. According to the rules, an armored tank can move diagonally in a blitz if the diagonally adjoining square is not occupied, but armored tanks cannot capture any enemy piece during a diagonal blitz unless the blitz is led by I.F. or C.T.
The circled letters in FIGS. 4 and 5 are used in the printed rules for the game but are not presently relevant. In FIG. 4, two I.F. 13 attempt to blitz diagonally. The hollow arrowhead 18 signifies that the blitz is not possible because the square on which the blitz would end is occupied by an enemy piece and I.F. cannot capture an enemy piece when moving diagonally.
FIG. 4 also shows two I.F. 13 moving laterally and an I.F. and an A.T. moving diagonally in successful blitzes, although no enemy pieces are captured in either of these blitzes. Two diagonally aligned C.T.s 14 are shown to be successfully blitzing in both directions in FIG. 4, with the capture of an enemy I.F. 13A in the forward direction.
The blitz illustrated in the second row of the game board 10 in FIG. 5 shows five pieces:representing I.F. 13 and two pieces representing C.T. 14 properly aligned for a blitz to the second square in the second row, eighth file. One of those pieces 13 and another piece repesenting I.F. 13 are properly aligned for a blitz forwardly along the seventh file, and two pieces representing I.F. 13 are properly aligned for a blitz diagonally to the square in the fourth row, eighth file. A piece representing A.T. 15 and a piece representing I.F. 13 are properly aligned for a diagonal blitz to the square in the third row, sixth file.
The game rules for pieces representing fighter planes 16, 16A are the same as the rules for the movement of knights in a chess game. Pieces representing planes 16, 16A are allowed to move ("fly") over other pieces in an L-shaped pattern; two squares in a straight line along a row or file and then one square at a right angle, as shown in FIG. 7. The pieces representing planes 16, 16A always stop on a square of a different color than the square from which the move was started. Pieces representing planes 16, 16A can capture an enemy piece only if that enemy piece is located on the square occupied by the piece 16 or 16A at the completion of the move.
The game rules for the movement of pieces representing attack helicopters 17, 17A allow those pieces to also fly over other pieces. The pieces representing helicopters 17, 17A may move either one or two squares, as a player desires, along a row or file and can fly over an occupied square to capture-an enemy piece occupying the square on which the helicopter lands, as shown in FIG. 8.
The game rules for the initial position and movement of pieces representing bombers 20, 20A are the same as chess rules for the movement of the queen, except the game rules allow pieces representing bombers 20, 20A to move (fly) over pieces of the same color as the bomber, but pieces 20, 20A cannot fly over pieces of the opposite color. As shown in FIG. 9, the rules allow pieces representing bombers 20, 20A to move in any one direction over any number of unoccupied squares, and capture any piece of another color than the bomber by landing on the square occupied by a piece of another color. The rules do not allow pierces representing bombers 20, 20A to combine two directions in one move.
The game rules for the initial position and movement of pieces representing command headquarters 21, 21A are the same as chess rules for the king. The pieces representing headquarters 21, 21A can move and capture pieces of an opposing player by moving to any one adjoining square that is not dominated by an opposing piece.
THE OBJECT OF THE GAME
One object of the game is for the players to maneuver their pieces in such a manner that the piece representing the opponent's headquarters (21 or 21A) is vulnerable to capture. According to the game rules, the player (player A) successfully placing pieces to make an opponent's (player B) headquarters piece vulnerable to capture must declare "radar lock". Here, a headquarters piece 21 or 21A of player B that is under radar lock is in the same position as a king under check in a game of chess. Player B has an opportunity to get out of radar lock by either (1) moving the vulnerable headquarters piece to a square that is not vulnerable to attack by a piece of player A; or (2) moving to an adjoining square and capturing the piece belonging to player A that has placed the headquarters piece of player B under radar lock; or (3) player B can move one of his pieces to capture the attacking piece of player A or to block the enemy's attack.
If none of the above are possible, the game is over. The other player declares "Victory". The word "Victory" is the term used in the rules of this game to signify that one player has won the game.
The rules of this game provide that if both players are unable to move any of their pieces without putting their Headquarters under "Radar Lock", a "Truce" is called and the game is a "Draw". The game is also a "Draw" if neither player can
capture the other's Headquarters. Or, the players can agree to end the game (battle) in a Draw.
The structure of the game board and the rules of the game have been deliberately patterned after chess to attract chess players to play this game without being confused by a whole set of new rules. Significant variations in the rules of chess have been made to adapt the logic of chess to a military environment. The result is a game that requires even more strategy than standard chess because the miniature military game pieces have movements that simulate the movements of the real military pieces represented by the miniature game pieces. All of the game pieces can move, attack, capture and/or retreat.
SIMULTANEOUS WARFARE
In another embodiment of the game, the game board 10 can be numbered as shown in FIG. 11, where each square has a double-digit number denoting the location of that square on the game board. For example, the square at the lower left of the game board has the double digits "11", indicating that the square is located in the first row, first file. Similarly, the square at the mid-portion of the game board 10, bearing the double digits "64". is located in the sixth row, fourth file.
This and other numbered game boards may be satisfactorily used to record the moves of the pieces during a game. The numbered game board shown in FIG. 11 has been found to be useful in playing Simultaneous Warfare, a variation of the military chess game of this invention.
The rules for Simultaneous Warfare call for two players using the numbered game board 10 shown in FIG. 11. The same game pieces shown in FIGS. 1 and 1A are used and the same rules are used in the game of Simultaneous Warfare as are used in the military chess game of the first embodiment of this invention, except that the players movements are made simultaneously, and not alternately, as in chess.
Instead, each player simultaneously makes a written notation of the move he is going to make. Then the players move their military game pieces on the numbered game board 10 in accordance with their written notations. Simultaneous movements of the military pieces likens the game to an actual battle where neither side knows the next move the enemy forces will make.
When both of the opposing players move one of their pieces to the same square, the highest ranking piece is allowed to make the move and capture the opposing piece, which is removed from the board.
If opposing pieces of the same rank reach a square at the same time, the successful movant is decided by chance, such as a flip of a coin or the roll of dice. The winner's piece makes the move and captures the loser's piece, which is removed from the board.
Simultaneous play continues until Radar Lock is achieved by one player. Thereafter, the players make alternate moves, as in the military chess game previously described until Victory is achieved or a Truce declared.
Although specific terms have been employed in describing the invention, they have been used in a descriptive and generic sense only and not for the purpose of limitation, the scope of the invention being determined by the appended claims when considered with this specification and the applicable prior art. | This invention is a board game wherein the board has the same number of squares as a chess board and each player has sixteen movable pieces, as in chess. The movable pieces are military pieces simulating military personnel, armament, and a headquarters. The rules of chess apply except that the military pieces are enabled to move in a manner simulating movement of military equipment, which enables the players to combine military strategy with chess-like logic. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. §120:
[0002] as a continuation application to U.S. application Ser. No. 10/737,193, which issued on Oct. 31, 2006 as U.S. Pat. No. 7,130,396; and
[0003] as a continuation-in-part application to U.S. application Ser. No. 09/841,133, which issued on Dec. 16, 2003 as U.S. Pat. No. 6,665,385.
[0004] Both the U.S. Pat. No. 7,130,396 and the U.S. Pat. No. 6,665,385 patents are incorporated by reference herein in their entirety.
BACKGROUND
[0005] The following description relates to a medical monitoring system having multiple communications channels, e.g., for providing alternative information pathways between a medical monitoring unit and a central monitoring station.
[0006] Advances in sensor technology, electronics, and communications have made it possible for physiological characteristics of patients to be monitored even when the patients are ambulatory and not in continuous, direct contact with a hospital monitoring system. For example, U.S. Pat. No. 5,959,529 describes a monitoring system in which the patient carries a remote monitoring unit with associated physiological sensors. The remote monitoring unit conducts a continuous monitoring of one or more physiological characteristics of the patient, such as the patient's heartbeat and its waveform, according to a medical condition of the patient.
[0007] An objective of such portable monitoring systems is to establish contact with a central; monitoring station (a.k.a., a central unit), which is in turn may contact with medical personnel and/or access the patient's medical records. The ability to establish contact allows the central unit to determine the existence of a medical emergency with the patient, and to render medical assistance to the patient during such an emergency. The ability to establish contact is also important psychologically to the patient, so that the patient knows that (s)he is not alone or out of touch. The portable monitoring systems may establish one or more communication links to the central unit through telephone land-lines, when the patient is in a location where land-line telephone access is readily available or through the cellular telephone system when land-line access is not available or an emergency suddenly occurs.
SUMMARY
[0008] The present inventors recognized that existing medical monitoring systems may be hampered by the fact that cellular telephone communication links are not available in many parts of the United States and in other countries. This unavailability arises because the cellular system infrastructure is not in place in relatively remote areas and because cellular telephone signals will not penetrate into many structures even if they are within the range of cellular telephone transceiver cell sites. As a result, the remote monitoring unit is unable to communicate with the central unit from many locations. The patient is therefore unable to obtain emergency assistance in those locations, and consequently feels isolated. Accordingly, the inventors developed various systems and techniques that help ensure wide-area communication availability for remote monitoring units of medical monitoring systems.
[0009] The systems and techniques disclosed here may include various combinations of the following features.
[0010] In one aspect, a medical monitoring system includes a sensor unit configured to sense one or more physiological characteristics of a patient, a monitoring unit in communication with the sensor unit and operable to communicate information relating to the sensed physiological characteristics to a central unit, and two or more communications channels operable to communicate between the monitoring unit and the central unit. The monitoring unit is operable to specify for transmission a data set that is tailored to a particular communications channel to be used to communicate the information relating to the sensed physiological characteristics to the central unit.
[0011] The tailored data set for transmission my be a subset of a full data set or may be information derived from a data set. More generally, the tailored data set may include a data set that is adapted according to one or more parameters of the selected communications channel.
[0012] The monitoring unit may further be operable to select a communications channel from among the two or more communications channel, for example, based on one or more predetermined criteria such the communications channels' relative availability, bandwidth, quality, latency, cost, reliability, and the like. The communications channels may include one or both of wired and wireless communications channels and, further, may include one or more of a land-line telephone network, a cellular telephone network, a paging network and a packet-switched data network.
[0013] In another aspect, a portable medical monitoring unit may be controlled by receiving sensor data from a sensor, the received sensor data representative of one or more physiological characteristics of a patient being monitored, selecting a communications channel from among multiple potential communications channels, specifying a data set for transmission to a central unit, the specified data set being adapted to the selected communications channel, and transmitting the specified data set over the selected communications channel to the central unit.
[0014] Selecting the communications channel from among the potential communications channels may be based on one or more predetermined criteria such as the communications channels' relative availability, bandwidth, quality, latency, cost and reliability.
[0015] Specifying the data set for transmission to the central unit may include adapting the data set according to one or more parameters of the selected communications channel. The specified data set for transmission may include a subset of a full data set or may be information derived from a data set.
[0016] The systems and techniques described here may provide one or more of the following advantages. For example, a medical monitoring system having a remote monitoring unit may provide enhanced communications coverage throughout the United States and/or much of the world. This communications coverage may include a wide geographical area and/or locations such as the interiors of buildings that are sometimes unavailable for cellular telephone coverage. This enhanced communications coverage increases the likelihood that the remote monitoring unit will be able to communicate with the central unit under emergency conditions. Equally importantly, the patient being monitored has better peace of mind of knowing that (s)he is rarely, if ever, out of touch with medical assistance. The present approach may be implemented relatively inexpensively, as it can rely on communications infrastructure that already is in place and operating, and it may be adapted to new communications technologies that become available. The remote monitoring unit can be made to work with this approach with little, if any, increase in size, weight, and/or power consumption to the remote monitoring unit.
[0017] Other features and advantages will be apparent from the following description taken in conjunction with the accompanying drawings and the claims.
DRAWING DESCRIPTIONS
[0018] FIG. 1 is a schematic diagram of a medical monitoring system; and
[0019] FIG. 2 is a block flow diagram of a method of operating the multiple communication channels.
DETAILED DESCRIPTION
[0020] FIG. 1 depicts a medical monitoring system 20 that includes a sensor system 22 having a sensor for monitoring any of a variety of physiological characteristics associated with a patient, for example, a heartbeat waveform, blood pressure, brain signals, blood chemistry, and the like. The sensor system 22 communicates with a remote monitoring unit (RMU) 24 that typically is either carried by the patient or is relatively physically close to the patient. The communication between the sensor system 22 and the remote monitoring unit 24 may be either wired or wireless, such as a short-range radio frequency link.
[0021] The remote monitoring unit 24 includes a microprocessor 26 in communication with the sensor system 22 . The microprocessor 26 performs computations as may be necessary and oversees the operation of a portable-monitoring unit transceiver system 28 that is also a part of the remote monitoring unit 24 . The portable-monitoring-unit transceiver system 28 communicates with a central unit (CU) 30 having a central-unit transceiver system 32 that supports communications of the types found in the portable-monitoring-unit transceiver system 28 and which will be discussed subsequently. The central unit 30 also includes a central unit microprocessor 34 that coordinates the central-unit transceiver system 32 and performs other analytical and control functions. The general features of a preferred form of the medical monitoring system 20 , other than those to be discussed subsequently, are described in U.S. Pat. No. 5,959,529, whose disclosure is incorporated by reference.
[0022] The portable-monitoring-unit transceiver system 28 includes a third-network transceiver 35 . The third-network transceiver 35 may be a two-way paging-network transceiver operable with the paging network. However, the third-network transceiver 35 may be of other types, such as a specialized emergency-network transceiver, a marine-network transceiver, and the like. Alternatively, or in addition, the third-network transceiver 35 may be configured to establish a communication link by other available means, among others, such as wired or wireless networks that implement communications protocols and standards such IP (Internet protocol), WiFi (IEEE 802.11x), WiMax (IEEE 802.16x), and/or GPRS (General Packet Radio Service). Moreover, the third network transceiver may be configured to communicate over either circuit-switched networks (e.g., traditional telephone networks) or over packet-switched data networks.
[0023] The example implementation shown in FIG. 1 includes the paging network transceiver 36 and its antenna 38 that selectively establish a third-network link (in this case a paging network link) with the central unit 30 . The paging network transceiver 36 operates using the existing paging network available throughout the United States and much of the rest of the world. Communication with the paging network is available in virtually every part of the United States and in most parts of the rest of the world. It is available in the open, inside buildings, in aircraft, and onboard ships. The paging network originally operated unidirectionally with signals conveyed only from the satellite to the paging unit, but it is now available in a bidirectional form as suggested by the term “transceiver”, an art-recognized contraction of “transmitter/receiver”. That is, the bidirectional paging transceiver 36 may either receive information or send information, via the existing paging system, to the central unit transceiver 32 .
[0024] The portable-monitoring-unit transceiver system 28 further includes a cellular telephone transceiver 40 and its antenna 42 , which may serve as a primary wireless network transceiver. The cellular transceiver 40 selectively establishes a cellular link with the central unit 30 . The cellular telephone transceiver 36 operates using the existing network of cell sites available through much of the United States and some of the rest of the world. Cellular communications links are operable in the open, inside most automobiles within range of cell sites, and inside many buildings, but are often not available in some buildings, in aircraft, or onboard ships. The cellular telephone transceiver 40 may either receive information or send information through the cellular network to the central unit transceiver 32 .
[0025] The portable-monitoring-unit transceiver system 28 further includes a land-line telephone transceiver 44 and its plug jack 46 . The land-line telephone transceiver 44 selectively establishes a land-line link with the central unit 30 . The land-line telephone transceiver 44 operates using the land-line system (which may also include microwave links of the land-lines and/or may provide one or more of POTS (Plain Old Telephone Service), DSL (Digital Subscriber Line) or ISDN (Integrated Services Digital Network) service) available through much of the United States and much of the rest of the world. Land-line telephone communications links are available through telephone central switching offices wherever there is a plug connection, but the need for physical access to a plug tends to limit the mobility of the patient. The land-line telephone transceiver 44 may either receive information or send information through the land-line system to the central unit transceiver 32 .
[0026] FIG. 2 depicts a sequence of events that may occur when communication is required between the remote monitoring unit 24 and the central unit 30 . A need for communications is first determined (sub-process 60 ). This sub-process typically occurs when the remote monitoring unit 24 determines that it needs to communicate with the central unit 30 , but it may also occur when the central unit 30 determines that it needs to communicate with the remote monitoring unit 24 . The former case will be discussed in detail, but the discussion is equally applicable to the latter case.
[0027] The land-line transceiver 44 is used if the land-line link is available (sub-process 62 ). That is, the microprocessor 26 seeks to open a land-line communication link to the central unit 30 through the land-line transceiver 44 . If there is no plug in the plug jack 46 or if it is otherwise not possible or feasible to dial up the central unit 30 , then the microprocessor 26 seeks to open a cellular link to the central unit 30 through the cellular telephone transceiver 40 (sub-process 64 ). The use of the land-line transceiver 44 typically is preferred to the use of the cellular telephone transceiver 40 , because the land-line communication link tends to be more reliable, more secure, and usually less costly, if available.
[0028] If the communication link is established either through the land-line transceiver 44 or the cellular transceiver 40 , then the microprocessor 26 uses a first processing routine stored therein that transmits a full data set through either of these wide-bandwidth communications channels. This is the desired operating mode of the medical monitoring system 20 , because its full data capabilities may be employed.
[0029] However, as noted above, in some instances neither the land-line link nor the cellular link is available due to reasons such as unavailability of the land line, unavailability of the cellular system, user overload of the cellular system, interference to wireless communications in the frequency band of the cellular system, or the like. In that case, the third-network transceiver 36 is used (sub-process 66 ) to employ an alternative communications channel such as the paging network or an available wired or wireless packet-switched network, such as the Internet. If the third-network provides a reduced communications bandwidth, e.g., in comparison the cellular or land-lines networks, then the microprocessor 26 may use a second processing routine stored therein that determines and transmits a reduced data set over the paging-network link. In some cases where the sensor system 22 obtains a small amount of data such as a single blood chemistry number, the full data set may be transmitted over the paging network transceiver 36 . In other cases where the sensor system 22 obtains much larger amounts of data, such as a heartbeat waveform, then it may not be possible or feasible (e.g., due to network latency or other delays) to transmit the full data set even if data compression techniques are used. The second processing routine is written to select some subset of the data (e.g., the most important) that is gathered by the sensor system 22 , and/or to calculate or otherwise generate secondary data from the gathered data (e.g., data derived from, and representative of, the sensed data), for transmission over the paging network transceiver 36 . In the case of the heartbeat, for example, the second processing routine may calculate a heart rate (number of beats per minute), amplitude, and waveform characteristics of selected portions of the full heartbeat signal for transmission within the bandwidth constraints of the third-network. The second processing routine would typically not select voice or other audio signals for transmission. This reduced data set, while not as complete as the full data set, is far better and more useful to the central unit 30 in diagnosing and aiding the patient than having no information and no contact at all.
[0030] It is possible to perform multiple serial communications between the remote monitoring unit 24 and the central unit 30 to transmit more information, but even in that case it is unlikely that the full data set can be conveyed. The selection of the content of the reduced data set, and thus the content of the second processing routine, is left to the individual situation and type of data being monitored for the individual patient.
[0031] More generally, the transceiver system 28 of the remote monitoring unit 24 may employ multiple (i.e., two, three, four or more) different communications channels for communicating information from the remote monitoring unit 24 to the central unit 30 . The microprocessor 26 then can rely on predetermined criteria (e.g., such as described in a table, database or software instructions) to select (and/or otherwise specifying or generating) a data set for transmission that is tailored to, or otherwise appropriate for, the particular communications channel being used. The predetermined criteria may be set or altered by a system designer or administrator, or even by a software process automatically, depending on several different factors including the types of physiological characteristics being monitored, the severity of the patient's condition, the available bandwidth, quality, latency, cost and/or reliability of the communications channel to be used, and the like.
[0032] The system described above may provide a communications hierarchy based upon a recognition that limited communications is better than no communications in many instances, and a recognition of the tradeoff between factors such as communications availability and bandwidth. Some currently available communications links are summarized in the following table, with the land-line telephone being a wired connection and the other communications links being wireless. However, it is emphasized that the use of the systems and techniques described here is not limited to these types of communications links and includes other presently available and future communications links:
Center Frequency Bandwidth Communications Link (MHZ) (Qualitative) Land-line telephone — very high Analog cellular phone 859 moderate Digital CDMA cellular phone 800 high Digital PCS CDMA cellular 1900 high phone Motorola Reflex paging 900 moderate Celemetry paging 859 very low
[0033] Thus, in the implementation described above the portable-monitoring-unit transceiver system of the medical monitoring system includes the land-line telephone transceiver and a digital cellular transceiver. However, when communication over these communications links is not available, one or more of the alternative, third-networks (e.g., the paging network) may be used as a backup. Even data communications over a low-bandwidth or moderate-bandwidth paging system is preferable to no communication in many situations.
[0034] Although a particular implementation been described in detail for purposes of illustration, various modifications and enhancements may be made, for example, by combining, rearranging or substituting different features or sub-processes for those disclosed above. Accordingly, other embodiments are within the scope of the following claims. | A device includes a patient-portable remote monitoring unit to monitor one or more physiological characteristics of an individual and convey information characterizing the one or more physiological characteristics to a remote station. The monitoring unit includes a transmitter system capable to employ a selected one of three or more different communications channels to convey the information to the remote station, and a selection unit to select from among the three or more different communications channels for conveying the information to the remote station. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a national stage application (under 35 U.S.C. §371) of PCT/EP2012/057044, filed Apr. 18, 2012, which claims benefit of German application 10 2011 007 661.1, filed Apr. 19, 2011.
[0002] The invention relates to a process for producing hydrogen by selective dehydrogenation of formic acid using a catalytic system based on a transition metal complex derived from a transition metal salt and at least one tripodal tetradentate ligand, where the transition metal is selected from the group consisting of Ir, Pd, Pt, Ru, Rh, Co and Fe. The transition metal complex can be used either as a homogeneous catalyst or a heterogenized metal complex which has been applied to a support.
PRIOR ART
[0003] Possible energy stores include not only electric stores (batteries), mechanical stores (pump stores) and thermal stores (power-heat coupling usually water stores) but also chemical stores. Among chemical stores, there has been a great deal of discussion about, in particular, methane (natural gas, CH 4 ) and hydrogen.
[0004] Hydrogen (H 2 ) is a gas which even today is used in many chemical reactions (e.g. Haber-Bosch process, Fischer-Tropsch process). In addition, H 2 can provide energy by reaction in internal combustion engines, chemical reactors or fuel cells. Owing to the clean combustion of hydrogen to form water, this energy store occupies a special position. For this reason, too, hydrogen technology will in future play a key role with regard to a sustainable energy supply.
[0005] However, a fundamental problem is still storage of hydrogen. The gas hydrogen is extremely volatile, highly inflammable and highly explosive in mixtures with oxygen gas (air). A hydrogen store which allows safe and easy handling of this gas is therefore of critical importance. In addition, the amount of hydrogen liberated should be restricted to the amount directly required. A preparation of hydrogen, with immediate start-up, is therefore a process to be preferred.
[0006] For the storage of hydrogen, there has been discussion of not only the “classical” methods (pressurized gas stores, liquefied gas stores, metal hydride stores) but currently also of various organic hydrogen-rich compounds. These include, for example, methanol, organic “hydrides” such as decalins or methylcyclohexane and also formic acid. The latter is in the form of a liquid at from 8 to 101° C., contains 4.4% by weight of H 2 and is nontoxic. Formic acid is thus a comparatively easy-to-handle hydrogen store. To be able to utilize the hydrogen present in the formic acid, the formic acid has to be selectively decomposed into hydrogen and carbon dioxide. This is successful only in the presence of a suitable catalyst.
[0007] First catalysts for the dehydrogenation of formic acid were described by Sabatier in 1912. Since this time, numerous catalytic systems for the selective dehydrogenation of formic acid have been described.
[0008] Heterogeneous catalysts are described, for example, in a publication by Williams and co-workers [R. Williams, R. S. Crandall, A. Bloom, Appl. Phys. Lett. 1978, 33, 381]. A Pd/C (1% by weight of Pd) catalyst is used. In this way, about 55 ml of hydrogen could be prepared from a 4 molar aqueous formic acid solution (4M) over a period of 10 minutes.
[0009] More recent research results of Xing et al. [X. Zhou, Y. Huang, C. Liu, J. Liau, T. Lu, W. Xing, ChemSusChem 2010, 3, 1379] show that good activities can be achieved at 92° C. using Pd@Au catalysts. Thus, up to 1.198 liters of gas (H 2 +CO 2 ) per minute and gram of catalyst could be produced. Overall, about 36 ml of gas could thus be evolved in the experiments, which is a number of orders of magnitude too little for industrial implementation. The gas mixture additionally contained over 30 ppm of CO, which makes gas purification necessary for direct use in a PEM fuel cell (requirements: CO<10 ppm).
[0010] The catalyst systems described in the publications cited by way of example are still very far from possible usability because of the high temperatures of >100° C. required, the low selectivities (high CO content) and low activities (few ml of hydrogen were generated per minute).
[0011] In WO 2008059630 A1, Fukuzumi et al. describe, for example, a heterobinuclear catalyst based on iridium. In illustrative reactions, the catalyst provided hydrogen (+CO 2 ) selectively from aqueous formic acid solution over a period of 25 minutes. In particular, the catalyst and many derivatives of the heterobinuclear catalyst are described in the manuscript. However, none of the heterobinuclear catalyst systems examined to date even approximately meet the minimum requirements, in particular in respect of activity and selectivity, for industrial use.
[0012] Significantly higher activities and selectivities at lower temperatures have hitherto been able to be observed in the case of homogeneous catalyst systems.
[0013] The group around Himeda et al. was able to develop a catalyst which is based on the noble metal iridium and combined comparatively high activities and good selectivities with a stability sufficient for the laboratory scale. At a temperature of 90° C., they achieved a turnover frequency (TOF) of 14 000 h −1 using a HCO 2 H/HCO 2 Na mixture. At low temperatures, no appreciable conversions were able to be observed [Y. Himeda, Green Chem. 2009, 11, 2018].
[0014] Industrially interesting homogeneous catalyst systems are based essentially on noble metal complexes. In 2008, Laurenczy et al. and Beller et al. independently developed the concept of storage of hydrogen in the form of formic acid. Based on their experiences in the hydrogenation of carbonates, Laurenczy et al. utilized a water-soluble ruthenium-TPPTS (tris-m-sulfonated triphenylphosphine trissodium salt) complex which can liberate hydrogen from an aqueous HCO 2 H/HCO 2 Na solution (9:1) at from 70° C. to 120° C. However, the activity of the catalyst decreases dramatically at temperatures below 70° C. (EP 1 918 247 A1).
[0015] Wills and co-workers utilized the ruthenium-based catalyst [RuCl 2 (DMSO)] in order to produce up to 1.4 l of gas (H 2 +CO 2 ) per minute at 120° C. from a formic acid/dimethyloctylamine mixture. Using triethylamine as base, up to 2.5 l of gas (H 2 +CO 2 ) per minute could briefly be produced, but at this temperature a major part of the amine used was carried out from the process together with the gas liberated. The high temperature required and the need to utilize a base (here amines) make this process uninteresting for practical use [D. J. Morris, G. J. Clarkson, M. Wills, Organometallics 2010, 132, 1496].
[0016] Beller et al. examined heterogeneous and homogeneous catalyst systems based on Pd, Rh, Ir, Ru, Cr, Mn, Fe, Co, Ni, Cu and Mo. Within this broad screening, Ru and Fe catalysts, in particular, were examined in detail for the preparation of hydrogen from formic acid in a mixture with amines. Thus, for example, a system consisting of [RuBr 3 ]xH 2 O together with PPh 3 displayed activities of up to 3630 h −1 TOF (turnover frequency) at 40° C.
[0017] The further-developed catalyst [RuCl 2 (benzene)]/dppe in 5HCO 2 H/4HexNMe 2 is to date the most active catalyst at temperatures below 80° C. With a TOF of 900 h −1 at 25° C. and a conversion of 100%, this catalyst system is the hitherto most active for the selective decomposition of formic acid into H 2 and CO 2 . As regards the development of a biological catalysis system for the selective dehydrogenation of formic acid, only a few catalysts which are not based on noble metals are known [A. Boddien, B. Loges, F. Gärtner, C. Torborg, K. Fumino, H. Junge, R. Ludwig, M. Beller, J. Am. Chem. Soc. 2010, 132, 8924; A. Boddien, F. Gäartner, R. Jackstell, H. Junge, A. Spannenberg, W. Baumann, R. Ludwig, M. Beller, Angew. Chem. 2010, 122, 9177-9181]. However, all catalysis systems tested were active only in the presence of visible light and bases (triethylamine, NEt 3 ).
[0018] Noble metal-containing catalysts have the disadvantage that they are costly, so that more inexpensive alternatives are sought, with base metal catalysts, e.g. iron catalysts, being possibilities. On irradiation with light, an in situ catalyst system consisting of Fe 3 (CO) 12 /PPh 3 /tpy displays significant activity for the selective generation of hydrogen from FA/TEA mixtures. Activity and stability were increased by means of a system having tribenzylphosphane (PBn 3 ) instead of PPh 3 . Thus, it was possible to prepare over 3.7 liters of gas (H 2 +CO 2 ) in a period of 51 hours, which corresponds to a turnover number (TON) of 1266. These are to date the only catalyst systems based on the cheap metal iron to be examined. They are summarized in a review (Boddien, Albert, Gäartner, Felix, Mellmann, Dörthe, Kammer, Anja, Losse, Sebastian, Marquet, Nicolas, Surkus, Annette-Enrica, Rajenahally, Jagadeesh, Junge, Henrik, Beller, Matthias, Loges, Björn, GIT 2010, 8, 576). The iron-based catalyst systems are not industrially practicable and do not come into question for use because of the activities achieved and a selectivity of about 10 000 ppm of CO and more.
[0019] None of the catalyst systems (homogeneous or heterogeneous) described hitherto meets the conditions linked to industrial implementation. High temperatures (>100° C.) and/or the presence of a base (NaHCO 2 or amines) or a precisely set pH of the solution are always necessary to achieve sufficient activity. In addition, only few catalysts meet the selectivity requirements (<10 ppm of CO).
[0020] It was therefore an object of the invention to seek inexpensive industrially usable catalyst systems for obtaining hydrogen from formic acid, which catalyst systems achieve high activities and operate under simple reaction conditions, preferably at room temperature. The reaction must be highly selective in order to avoid dehydration (H 2 O+CO) since, for example, fuel cells which operate using hydrogen gas tolerate only small amounts of CO.
A BRIEF DESCRIPTION OF THE FIGURES
[0021] FIG. 1 shows an illustrative experiment according to example 9 of the invention.
[0022] FIG. 2 shows an illustrative experiment according to example 10 of the invention.
DESCRIPTION OF THE INVENTION
[0023] The invention describes the use of transition metal complexes as catalysts in order to decompose formic acid highly selectively into hydrogen and carbon dioxide at low (≦100° C.) temperatures and preferably under atmospheric pressure (1 bar). The process of the invention is characterized in that hydrogen is liberated selectively from formic acid at temperatures of from 0° C. to 100° C. using a catalyst system which consists of a transition metal salt and a tripodal tetradentate ligand, where the transition metal is selected from the group consisting of Ir, Pd, Pt, Ru, Rh, Co and Fe. This catalytic system can be used as homogeneous or heterogenized metal complex and does not require any further auxiliaries (e.g. bases, amines) or specific toxic solvents, nor high temperatures. The content of carbon monoxide in the gas mixture is below the required threshold for direct combustion in H 2 /O 2 PEM fuel cells.
[0024] The invention described leads to selective liberation of hydrogen and carbon dioxide in a ratio of 1:1 (H 2 :CO 2 =50:50% by volume) from formic acid. A virtually pure H 2 /CO 2 mixture can be obtained in the low to medium temperature range by means of the catalyst system. As mentioned above, no specific auxiliaries or specific reaction conditions (e.g. pH) are necessary for this reaction. In addition, biodegradable solvents, for example, can be used when the catalyst system is used as a homogeneous system. Furthermore, the catalyst system used displays a high activity and stability. In addition, the reaction can be controlled in respect of gas evolution by selection of the temperature, of the pressure, irradiation with light and/or amount of formic acid.
[0000]
[0025] The catalyst can be separated off after a reaction and be reused. The catalyst is stable over a wide temperature and pressure range, in particular under acidic conditions (pKa of formic acid=3.77).
[0026] The reaction surprisingly takes place even at low temperatures of about 0° C., with constant hydrogen evolution occurring. The reaction temperatures should generally be in the range from 20 to 100° C. The temperature range from 25 to 80° C. is to be preferred. The temperature range from 40 to 80° C. is most preferred. Hydrogen can be generated highly selectively from formic acid over the entire temperature range proposed. Here, the formic acid is quantitatively converted into hydrogen and carbon dioxide.
[0027] The temperature plays a critical role for the activity of the reaction. Since the reaction also proceeds at room temperature (˜20-25° C.), the required heat of reaction can be withdrawn from the surroundings. Should a higher activity be desired, the temperature of the reaction space can be increased appropriately, preferably by means of a heating unit. This heating unit can be an oil bath, electric heating element, water bath or heat exchanger, etc. The waste heat of a connected fuel cell can advantageously be utilized.
[0028] Fundamentally, no additional bases, e.g. amines, are required for the dehydrogenation of formic acid using the catalyst system according to the invention, but formates, e.g. NaHCO 2 , can optionally be added. The amount of base used should not exceed an HCO 2 − /HCO 2 H ratio of 1:1. The formate salt can be any salt. The cation can be an organic or inorganic cation. The cation is preferably an inorganic cation, particularly preferably with metallic character. For example, the cation can be a sodium, Mg or calcium ion.
[0029] The process can also be used for cooling by a heat exchanger (including a suitable medium) connecting the reaction unit to another object.
[0030] The decomposition of formic acid can, when the reaction space is closed, generate a defined pressure. The reaction can be carried out at various pressures. The pressure range prevailing during operation can be from 1 to 200 bar, preferably 1-10 bar.
[0031] The catalyst system described can consist of a catalyst generated in situ, metal source and ligand, or a previously synthesized metal complex. Preference is given to using, according to the invention, a catalyst system which is a metal complex consisting of a cation and anion or a neutral metal complex having the general formula (Ia) or (Ib),
[0000] [M(X) m (L) n ] + Y − (Ia)
[0000] M(X) m (L) n (Ib)
In these formulae, M, X, L, m and n have the following meanings: M is a transition metal selected from the group consisting of Ir, Pd, Pt, Ru, Rh, Co and Fe. M is preferably Ru, Co or Fe. X is selected from the group consisting of N 2 , H 2 , H, CO, CO 2 , H 2 O, halide, acetylacetonate (acac − ), perchlorate (ClO 4 2− ) and sulfate (SO 4 2− ), formate (HCO 3 − ), m is 1, 2, 3, 4, 5 or 6; preferably 1, 2 or 3; n is 1 or 2. L is a tripodal ligand of the general formula (II):
[0000]
where
D and Z are identical or different and are each selected from the group consisting of N, O, P and S; o, p=0, 1, 2 or 3; R 1 , R 2 are identical or different and are each selected from the group consisting of alkyl (C1-C6), cycloalkyl (C3-C10) and aryl. R 3 , R 4 are identical or different and are each selected from the group consisting of alkyl (C1-C6), cycloalkyl (C3-C10), aryl and heteroaryl; q, r=1 or 2; where D and/or Z can be coordinated to the metal.
Y − is a monovalent anion selected from the group consisting of halides, P(R) 6 − , S(R) 6 − , B(R) 4 − , where R is an alkyl (C1-C6), cycloalkyl (C3-C6), aryl or halogen radical, triflate and mesylate anions. Preference is given to Y − ═BF 4 − or BPh 4 − .
[0045] Halogen or halides encompasses Cl, F, Br and I.
[0046] As examples of alkyl groups, it is possible for methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl and n-hexyl to occur. As examples of cycloalkyl groups, mention may be made of cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl.
[0047] The term aryl refers, for the purposes of the invention, to aromatic ring systems which can be phenyl, naphthyl, phenanthrenyl and anthracenyl.
[0048] The term heteroaryl refers to heteroaromatic ring systems which can be five-membered and six-membered heterocycles in which at least one carbon atom has been replaced by nitrogen, oxygen and/or sulfur, preferably pyridine, quinoline, pyrimidine, quinazoline, furan, pyrazole, pyrrole, imidazole, oxazole, thiophene, thiazole, triazole.
[0049] Particular preference is given to metal complexes in which M is Ru, Co or Fe, particularly preferably Fe. m is preferably 1 or 2. n is preferably 1.
[0050] Preferred ligands of the general formula (II) are those in which D is nitrogen (N) or phosphorus (P). Z is preferably phosphorus (P).
[0051] R 1 , R 2 are identical or different and are preferably selected from the group consisting of alkyl (C1-C6) and phenyl. o and p arc preferably 0 or 1, where at least o or p=1.
[0052] R 3 and R 4 are preferably phenyl. q and r are preferably 1.
[0053] Y − is preferably BF 4 − or BPh 4 − .
[0054] The ligand to be used is preferably a tetradentate ligand which is coordinated to the metal center. The greatest preference is given to the ligands
a) tetraphos [PP 3 —(II) D and Z═P, R 1 and R 2 ═CH 2 and o and p=1 and also R 3 , R 4 =phenyl and q=1, r=1], b) tris(2-(diphenylphosphino)phenyl)phosphine, [L1—(II) D and Z═P, R 1 =phenyl and o=1, p=0, and also R 3 , R 4 =phenyl and q=1, r=1], c) tris(2-(diphenylphosphino)benzyl)phosphine, [L2—(II) D and Z═P, R 1 =phenyl and R 2 ═CH 2 , o=1, p=1, and also R 3 , R 4 =phenyl and q=1, r=1], and d) tris((diphenylphosphino)methyl)amine, [L3—(II) D=N and Z═P, R 1 ═CH 2 and o=1, p=0, and also R 3 , R 4 =phenyl and q=1, r=1].
[0059] The catalyst can be formed in situ from a suitable metal source and a suitable ligand, or can be a previously prepared defined metal complex.
[0060] If the complex is to be generated in situ, a metal source is used as precatalyst together with a ligand of the general formula (II).
[0061] Preference is given to using an iron source, Fe(0), Fe(II) or Fe(III), as metal source and a ligand of the general formula (II). Fe sources can be, for example, Fe(acac) 2 ; Fe(acac) 3 ; Fe(ClO 4 ) 2 , Fe(ClO 4 ) 3 or Fe(BF 4 ) 2 ×6 H 2 O. As Co source, preference is given to using Co(BF 4 ) 2 .6H 2 O, Co(acac) 2 ; Co(acac) 3 . A preferred Ru source is Ru(acac) 3 ; [RuCl 2 (benzene)] 2 , [RuCl 2 (p-cymene)] 2 , RuCl 3 ×H 2 O, RuBr 3 xH 2 O.
[0062] Ligands which are particularly preferably used are tetraphos (PP 3 ) or tris(2-(diphenylphosphino)phenyl)phosphine (L1).
[0063] In this preferred variant (in situ catalyst) of the process of the invention, the ligand is added in a substoichiometric or superstoichiometric amount to the metal source; the ratio of metal source: ligand is preferably 1:1 or with an excess of ligand.
[0064] Metal complexes of the general formula (Ia) which are very particularly preferably used in the process of the invention are, for example, [Fe(acac)(PP 3 )]BPh 4 ), [Fe(acac)(PP 3 )]BF 4 , [Fe(ClO 4 )(PP 3 )]BPh 4 , [Fe(ClO 4 )(PP 3 )] BF 4 , [FeH(PP 3 )]BPh 4 , [FeH(PP 3 )]BF 4 , [FeH(H 2 )(PF 3 )]BPh 4 , [FeH(H 2 )(PP 3 )]BF 4 , [FeF(PP 3 )]BPh 4 and [FeF(PP 3 )]BF 4 , [FeCl(PP 3 )]BPh 4 and [FeCl(PP 3 )]BF 4 , [FeBr(PP 3 )]BPh 4 and [FeBr(PP 3 )]BF 4 , and also FeF(L1)BPh 4 .
[0065] The catalyst can be used as homogeneous or heterogenized metal complex. When the metal complex described is used as homogeneous complex, a suitable solvent should be used for carrying out the reaction. Suitable solvents for the reaction (decomposition of formic acid) are selected from the group consisting of formamides, ethers, esters, alcohols and carbonates, e.g. DMF, triglyme, diglyme, THF, dioxane, PEG and propylene carbonate. Preference is given to using THF, PEG and propylene carbonate as solvent in the homogeneous process according to the invention. The preferred propylene carbonate, in particular, has a series of advantages since it has a high boiling point and also a low toxicity and is known to be completely biodegradable.
[0066] In the production of a heterogenized complex, the SILP technology is particularly preferred, alongside other methods. Here, for example, a defined previously synthesized complex is dissolved in a suitable ionic liquid and applied to activated SiO 2 . The powder obtained in this way is then preferably used for the reaction of the formic acid.
[0067] The hydrogen gas produced is virtually free of carbon monoxide and can be fed directly into a fuel cell which produces power. In addition, the hydrogen can be utilized in all internal combustion engines. In addition, the gas mixture produced, hydrogen and carbon dioxide, or the separated gases, can be utilized for chemical reactions. For use in an H 2 /O 2 PEM fuel cell, the hydrogen gas can optionally be purified using an activated carbon filter.
[0068] The reaction can be carried out in an apparatus which allows continuous production of hydrogen. For this purpose, a stock vessel containing formic acid can be connected by means of a suitable pump to a reactor which contains the active catalyst system. The reaction is started by introduction of the formic acid and an H 2 :CO 2 gas mixture (1:1) is obtained. This gas mixture can be reacted, for example, in an H 2 /O 2 PEM fuel cell.
[0069] High activities with a TOF of more than 9000 h −1 and a stable TON above 92 000 were able to be achieved with high selectivity (CO<10 ppm) when using a preferred in situ catalyst system composed of an Fe source and the ligand PP 3 in propylene carbonate as solvent.
[0070] When the preferred catalyst system is used according to the invention, it is possible to generate, for example, 0-3.3 liters of H 2 /min/mmol of Fe. The values fluctuate depending on the amount of formic acid to be used, solvents, reactor volume, temperature and pressure.
[0071] The catalyst system which is preferably used according to the invention is thus equivalent to previous systems based on the use of noble metal-containing catalyst systems. In the present case, the reaction proceeds without additions of bases or other additives such as Co catalysts. In particular, the possibility of using propylene carbonate as biodegradable solvent also makes the reaction industrially interesting.
EXAMPLES
Example 1
Preparation of the ligands L1-L3
[0072]
[0000]
Designation
Formula
L1
L2
L3
1a) Preparation of L1 (tris(2-(diphenylphosphino)phenyl)phosphine)
[0073] 1.5 g (4.4 mmol) of (2-bromophenyl)diphenylphosphine are dissolved in 30 ml of absolute THF (tetrahydrofuran) under argon with magnetic stirring in a 100 ml three-neck flask provided with thermometer and reflux condenser. The mixture is cooled to −78° C. by means of a cold bath and, at this temperature, 3 ml of 1.6 N n-butyllithium in hexane (4.8 mmol) are added to the mixture by means of a dropping funnel over a period of 10 minutes. The mixture is stirred at this temperature for 30 minutes. 0.13 ml of phosphorus trichloride dissolved in 5 ml of absolute THF is subsequently added at this temperature over a period of 5 minutes. The reaction mixture is allowed to come to room temperature over a period of 1 hour while stirring, and is subsequently heated at reflux temperature (about 65° C.) for 1 hour. The solution is subsequently cooled and evaporated to dryness under reduced pressure. 30 ml of absolute toluene are added and 20 ml of water (degassed) are introduced. The toluene phase is washed three times with 20 ml of water and dried using magnesium sulfate. After filtration, the solution is evaporated to 10 ml under reduced pressure and admixed with 50 ml of absolute methanol. A white solid precipitates over a period of half an hour. This is the target product and is filtered off and dried under reduced pressure. The yield is 0.6 g (50%) of tris(2-(diphenylphosphino)phenyl)phosphine.
[0074] 1 H-NMR (300 MHz, CD 2 Cl 2 δ (ppm): 6.5-7.3 m, 13 C-NMR (75 MHz, CD 2 Cl 2 δ (ppm): 128.4-128.8 (m), 129.0 (d, J PC =21 Hz), 133.9-134.3 (m); 135.1-135.5 (m) 31 P-NMR (121 MHz, CD 2 Cl 2 ) δ (ppm): −13.1-−14.5 (m, 3 P), −18.2-−23.5 (m, 1 P). HRMS: calculated for C 54 H 42 P 4 : 814.22315; found: 814.221226.
1b) Preparation of L2 (tris(2-(diphenylphosphino)benzyl)phosphine
[0075] 2.2 ml (3.5 mmol) of 1.6 N n-butyllithium in hexane are transferred under argon into a 100 ml three-neck flask provided with thermometer and reflux condenser. The hexane is taken off at room temperature under reduced pressure (2 torr). 20 ml of absolute ether and 0.6 ml of TMEDA are added. 1 g of diphenyl (o-methylphenyl)phosphine is then added at room temperature with magnetic stirring. Orange-colored crystals precipitate within a few minutes. The crystallization is allowed to progress for about 30 minutes and the supernatant solution is then filtered off, 15 ml of n-pentane are added and the mixture is cooled to −70° C. At this temperature, 0.11 ml (0.165 g, 1.2 mmol) of PCl 3 dissolved in 5 ml of pentane is added dropwise by means of a dropping funnel. The mixture is subsequently allowed to come to room temperature while stirring and 20 ml of absolute THF are added.
[0076] The solution is stirred for another 2 hours, the solvent is subsequently removed under reduced pressure and 20 ml of absolute toluene are added. The solution is washed three times with 10 ml of degassed water, dried over sodium sulfate and the toluene is subsequently removed under reduced pressure. The solution is taken up in 5 ml of methylene chloride, and 40 ml of MeOH are added; some brown precipitate precipitates and the solution is decanted off from this and the solution is evaporated. The product tris(2-(diphenylphosphino)benzyl)phosphine is obtained in 95% purity as a solid (yield=350 mg, 33%) 1 H-NMR (300 MHz, acetone d 6 δ (ppm): 7.5-6.5 (m, 42H), 3.62-3.58 8 m, 1.2; H), 3.2-3.17 (bs, 3.6; H), 2.15-2.0 (m, 1.2; H), 13 C-NMR (75 MHz, acetone d 6 δ (ppm): 138 (d, JPC=12 Hz), 135-134 (m), 126.9 (d, J PC =4 Hz), 68 (s), 26 (s) 31 P-NMR (121 MHz, acetone d6) δ (ppm): −5.1 (q, J pp =23 Hz, 1 P), −15.4 (d, J PP =23, 3 P). HRMS: calculated for C 57 H 47 P 4 [M+−1]: 855.26227; found: 855.262506.
1c) Preparation of L3 tris((diphenylphosphino)methyl)amine
[0077] 1.9 g (6.7 mmol) of bis(hydroxymethyl)diphenylphosphonium chloride, 0.12 g (2.2 mmol) of ammonium chloride, 1.9 ml of triethylamine and 25 ml of absolute methanol are heated under reflux (about 80° C.) under argon for 2 hours with magnetic stirring in a 100 ml three-neck flask provided with thermometer and reflux condenser. The target product precipitates as a white precipitate; after cooling, the mixture is filtered and the product is washed once with 8 ml of methanol. The yield is 3.27 g, 80%: 1 H-NMR (300 MHz, CD 2 Cl 2 δ (ppm): 7.4-7.2 (m, 30H), 3.8 (d, J PH =4.5 Hz, 6H), 13 C-NMR (75 MHz, CD 2 Cl 2 δ (ppm): 138.3 (d, J PC =12.8 Hz), 133.5 (d, JPC=18.5 Hz), 128.9 (s), 68 (s), 128.6 (d, JPC=6.9 Hz), 31 P-NMR (121 MHz, CD 2 Cl 2 ) S (ppm): −28.7 (s). HRMS: calculated for C 39 H 36 NP 3 [M]: 610.19769; found: 610.197315
Example 2
Preparation of the Metal Complexes K1-K9
[0078]
[0000]
Designation
Gen. formula
K1
[FeF(PP 3 )]BPh 4
K2
[FeCl(PP 3 )]BPh 4
K3
[FeBr(PP 3 )]BPh 4
K4
[FeH(PP 3 )]BPh 4
K5
[FeH(PP 3 )]BF 4
K6
[FeH(H 2 )(PP 3 )]BPh 4
K7
[Fe(acac)(PP 3 )]BPh 4
K8
[Fe(ClO 4 )(PP 3 )]BPh 4
K9
[FeF(L1)]BF 4
Preparation of K1, [FeF(PP 3 )]BPh 4
[0079] 0.50 mmol of Fe(BF 4 ) 2 *6H 2 O (169 mg) and 0.55 mmol of tris[(2-diphenylphosphino)ethyl]phosphane (369 mg) are firstly introduced in a countercurrent of argon into a Schlenk vessel (50 ml). 10 ml of distilled THF were subsequently introduced into the flask in a countercurrent of argon. The solution was stirred at room temperature for about 2 hours. 1.5 eq. (257 mg) of NaBPh 4 were then added. The deep purple solution was subsequently evaporated to 5 ml under reduced pressure and admixed with 10 ml of distilled EtOH and stored overnight in a refrigerator (˜5° C.). The precipitated purple solid was then filtered off and washed with 4×2 ml of cold EtOH and 2×1 ml of n-hexane. The purple solid was subsequently dried at 10 −3 mbar using a high-vacuum pump; m product =428 mg (η=80%) HRMS: calculated for C 42 H 42 FeFP 4 : 745.1565; found 745.1573.
Preparation of K2, [FeCl(PP 3 )]BPh 4
[0080] 0.54 mmol of FeCl 2 (68.4 mg) and 0.59 mmol of tris[(2-diphenyl-phosphino)ethyl]phosphane (396 mg) are firstly introduced in a countercurrent of argon into a Schlenk vessel (50 ml). 50 ml of distilled EtOH were subsequently introduced in a countercurrent of argon into the flask. The solution was stirred under reflux for about 2 hours. 0.7 mmol (239 mg) of NaBPh 4 were then added. The deep purple solution was subsequently stored overnight in a refrigerator (˜5° C.). The precipitated purple solid was then filtered off and washed with 5×5 ml of H 2 O and 5×5 ml of EtOH. The solid was then recrystallized from EtOH/H 2 O/acetone (10/1/1). The purple solid (powder) was finally dried at 10-3 mbar using a high-vacuum pump; m product =490 mg (η=84%) HRMS: calculated for C 42 H 42 FeClP 4 : 761.1211; found 761.1271.
Preparation of K3, [FeBr(PP 3 )]BPh 4
[0081] 0.50 mmol of Fe(Br) 2 (108 mg) and 0.55 mmol of tris[(2-diphenyl-phosphino)ethyl]phosphane (369 mg) are firstly introduced in a countercurrent of argon into a Schlenk vessel (50 ml). 20 ml of distilled EtOH were subsequently introduced in a countercurrent of argon into the flask. The solution was stirred at room temperature for about 2 hours. 1.5 eq. (257 mg) of NaBPh 4 were then added, resulting in precipitation of a dark deep purple solid. The precipitated solid was then filtered off and washed with 4×2 ml of cold EtOH and 2×1 ml of n-hexane. The purple solid was subsequently dried at 10 −3 mbar using a high-vacuum pump; m product =563 mg (η=94%) HRMS: calculated for C 42 H 42 FeBrP 4 : 807.07534; found 807.07451.
Preparation of K4, [FeH(PP 3 )]BPh 4
[0082] 0.67 mmol of Fe(BF 4 ) 2 *6H 2 O (226 mg) and 0.67 mmol of tris[(2-diphenyl-phosphino)ethyl]phosphane (450 mg) and 1.5 eq. of NH 4 BPh 4 are firstly introduced in a countercurrent of argon into a Schlenk vessel (50 ml). 30 ml of distilled THF were subsequently introduced in a countercurrent of argon into the flask. The solution was cooled to −78° C. by means of a dry ice-ethanol suspension. After stirring for 3-6 hours, the solution was slowly warmed to room temperature. The deep orange/red solution was subsequently evaporated to ˜2 ml under reduced pressure and admixed with 15 ml of distilled EtOH and stored overnight in a refrigerator (˜5° C.). The precipitated orange solid was subsequently filtered off and washed with 5×5 ml of cold EtOH. The orange solid was subsequently dried at 10 −3 mbar using a high-vacuum pump; m product =538 mg (η=76%) HRMS: calculated for C 42 H 43 FeP 4 : 727.16599; found 727.16478.
Preparation of K5, [FeH(PP 3 )]BF 4
[0083] 0.22 mmol of Fe(BF 4 ) 2 *6H 2 O (75 mg) and 0.22 mmol of tris[(2-diphenyl-phosphino)ethyl]phosphane (150 mg) and 0.55 mmol of NaBPh 4 are firstly introduced in a countercurrent of argon into a Schlenk vessel (50 ml). 30 ml of distilled THF were subsequently introduced in a countercurrent of argon into the flask. The solution was cooled to −78° C. by means of a dry ice-ethanol suspension. After stirring for 3-6 hours, the solution was slowly warmed to room temperature. The deep orange/red solution was subsequently evaporated to ˜2 ml under reduced pressure and admixed with 15 ml of distilled EtOH and stored overnight in a refrigerator (˜5° C.). The precipitated orange solid was then filtered off and washed with 5×5 ml of cold EtOH. The orange solid was subsequently dried at 10 −3 mbar using a high-vacuum pump; m product =143 mg (η=80%) HRMS: calculated for C 42 H 43 FeP 4 : 727.1660; found 727.1652.
Preparation of K6, [FeH(H 2 )(PP 3 )]BPh 4
[0084] 0.22 mmol of Fe(BF 4 ) 2 *6H 2 O (75 mg) and 0.22 mmol of tris[(2-diphenyl-phosphino)ethyl]phosphane (150 mg) and 0.55 mmol of NaBPh 4 are firstly introduced in a countercurrent of hydrogen into a Schlenk vessel (50 ml). 15 ml of distilled THF were subsequently introduced in a countercurrent of hydrogen into the flask. The solution was cooled to −78° C. by means of a dry ice-ethanol suspension. After stirring for 3-6 hours, the solution was slowly warmed to room temperature. The deep yellow/orange solution was subsequently evaporated to 2 ml under reduced pressure and admixed with 15 ml of distilled EtOH and stored overnight in a refrigerator (˜5° C.). The precipitated yellow solid was then filtered off and washed with 5×5 ml of cold EtOH. The yellow solid was dried in a countercurrent of H 2 ; m product =187 mg=80%).
[0085] 1 H-NMR (400 MHz, THF d 8 δ (ppm): −7.56 ppm (s, 2H), −12.47 ppm (AM 2 Q, J(HP A )=45.1 Hz, J(HP M )=58.2 Hz, J(HP Q )=15.2 Hz), 1H), 13 C-NMR (75 MHz, THF d 8 δ (ppm): 126.58-139.93 (m, 6 C), 29.05-32.84 (m, 1 C) 31 P-NMR (121 MHz, THF d 8 ) δ (ppm): 89.9 (m, 3 P), 173.6 (m, 1 P).
Preparation of K7, [Fe(acac)(PP 3 )]BPh 4
[0086] 0.50 mmol of Fe(acac), (127 mg) and 0.55 mmol of tris[(2-diphenyl-phosphino)ethyl]phosphane (369 mg) were firstly introduced in a countercurrent of argon into a Schlenk vessel (50 ml). 20 ml of distilled EtOH were subsequently introduced in a countercurrent of argon into the flask. The solution was stirred at 50° C. for about 3 hours. 1.5 eq. (240 mg) of NaBPh 4 were then added. The precipitated solid was then filtered off and washed with 4×2 ml of cold EtOH and 2×1 ml of n-hexane. The solid was subsequently dried at 10 −3 mbar using a high-vacuum pump; m product =310.6 mg (η=54%).
Preparation of K8, [Fe(ClO 4 )(PP 3 )]BPh 4
[0087] 0.30 mmol of Fe(ClO 4 ) 2 (76 mg) and 0.33 mmol of tris[(2-diphenyl-phosphino)ethyl]phosphane (222 mg) are firstly introduced in a countercurrent of argon into a Schlenk vessel (50 ml). 5 ml of distilled THF were subsequently introduced in a countercurrent of argon into the flask. The solution was stirred at room temperature for about 24 hours. 0.4 mmol (136 mg) of NaBPh 4 were then added. The deep purple solution was subsequently evaporated to ˜2 ml under reduced pressure and admixed with 5 ml of distilled EtOH and stored overnight in a refrigerator (˜5° C.). The precipitated violet solid was then filtered off and washed with 4×2 ml of cold EtOH and 2×1 ml of n-hexane. The purple solid was subsequently dried at 10 −3 mbar using a high-vacuum pump; m product =150 mg (η=43%).
Preparation of K9, [FeF(L1)]BF 4
[0088] 0.275 mmol of Fe(BF4) 2 ×6 H 2 O (93 mg) and 0.31 mmol of tris[(2-diphenyl-phosphino)phenyl]phosphane (225 mg) are firstly introduced in a countercurrent of argon into a Schlenk vessel (50 ml). 20 ml of distilled THF were subsequently introduced in a countercurrent of argon into the flask. The solution was stirred at 20° C. for about 3 hours. The THF was then distilled off under reduced pressure, the solid was taken up in 5 ml of CH 2 Cl 2 and covered with a layer of 40 ml of Et 2 O. A deep violet solid precipitated overnight; this is filtered off and dried under reduced pressure and represents the target product (including 1 equivalent of CH 2 Cl 2 as solvent of crystallization). Yield=186 mg (80%).
Example 3
Experimental Setup and Procedure for the Decomposition of Formic Acid
[0089] Description of the experimental setup for automatic determination of gas volumes: Boddien et al. GIT 2010, 8, 576.
Example 4
[0090] Obtaining hydrogen from formic acid utilizing the metal catalyst systems K1 and K4-K7
Reaction Conditions:
[0091] 5.3 μmol of catalyst (100 ppm) in 2 ml of HCO 2 H, 3 ml of propylene carbonate, T=40° C., measured using a gas burette, (H 2 :CO 2 1:1)
[0000]
Designation
Catalyst
TON 2 h
TON 3 h
K1
[FeF(PP 3 )]BPh 4
838
1243
K4
[FeH(PP 3 )]BPh 4
487
724
K5
[FeH(PP 3 )]BF 4
745
1135
K6
[FeH(H 2 )(PP 3 )]BPh 4
727
1129
K7
[Fe(acac)(PP 3 )]BPh 4
486
744
Example 5
[0092] Obtaining hydrogen from formic acid with in situ generation of the metal catalyst system using various metal sources and the ligand tris[(2-diphenylphosphino)ethyl]phosphine (PP 3 ); MW 670.69052, melting point 134-139° C., commercially available from Acros or Sigma Aldrich.
Reaction Conditions:
[0093] 5.3 μmol of metal precatalyst (100 ppm) in 2 ml of HCO 2 H, 3 ml of propylene carbonate, 10.6 μmol of PP 3 (2 eq.), T=60° C., measured using a gas burette, (H 2 :CO 2 1:1)
[0000]
TABLE 1
Various metal sources for the production
of hydrogen from formic acid.
V 3 h (H 2 + CO 2 )
No.
Metal precatalyst
[ml]
TON 3 h
1
Fe(BF 4 )•6H 2 O
1684
6512
2
Co(BF 4 ) 2 •6H 2 O
51
197
3
Ru(acac) 3
654.5
2521
[0000]
TABLE 2
Various iron sources for the production
of hydrogen from formic acid.
η CAT
V(H 2 + CO 2 ) (3 h)
No.
Fe catalyst
[μmol]
[ml]
TON (3 h)
1
Fe(BF 4 ) 2 •6H 2 O
5.27
1684
6512
2
Fe(acac) 2
5.31
1510
5794
3
Fe(acac) 3
5.32
1839
7042
4
Fe(ClO 4 ) 2
5.29
954
3674
5
Fe(ClO 4 ) 3
5.3
1339
5148
Example 6
[0094] Selective production of hydrogen from formic acid with in situ generation of the metal catalyst system using the iron(II) source Fe(BF 4 ) 2 ×6 H 2 O; CAS number: 13877-16-2, molecular weight: 337.55, commercially available from Tanumal Chemical Complex Bldg. OK 74015 USA and various ligands.
[0000]
Ligand
Temperature
V 3 h [ml]
TON 3 h
L1
60
69
267
L1
40
38
71
L2
40
2
8
L3
40
3
12
[0095] 5.3 μmol of Fe(BF 4 ) 2 .2H 2 O (100 ppm), 2 ml of HCO 2 H, 3 ml of propylene carbonate, 10.6 mmol of ligand.
Example 7
[0096] Selective production of hydrogen from formic acid with in situ generation of the metal catalyst system using the iron(II) source Fe(BF 4 ) 2 ×6 H 2 O; CAS number: 13877-16-2, molecular weight: 337.55, commercially available from Tanumal Chemical Complex Bldg. OK 74015 USA and the ligand tris[(2-diphenyl-phosphino)ethyl]phosphine (PP 3 ) in various solvents.
Reaction Conditions:
[0097] 5.3 μmol of metal precatalyst Fe(BF 4 ) 2 *6H 2 O (100 ppm) in 2 ml of HCO 2 H, 3 ml of propylene carbonate, 10.6 mmol of PP 3 (2 eq.), T=60° C., measured using a gas burette, (H 2 :CO 2 1:1)
[0000]
TABLE 3
Solvent
V3 h/ml
TON 3 h
Dioxane
1506
5817
THF
1567
6053
DMF
104
402
Propylene carbonate
2188
8454
PEG Mn ~200
726
2803
PEG Mn ~285-315
985
3806
Example 8
[0098] Selective production of hydrogen from formic acid with in situ generation of the metal catalyst system using the iron(II) source Fe(BF 4 ) 2 ×6H 2 O and the ligand tris[(2-diphenylphosphino)ethyl]phosphine (PP 3 ) at various temperatures.
Reaction Conditions:
[0099] 5.3 μmol of Fe(BF 4 ) 2 .6H 2 O, 2 or 4 eq. of PP 3 in 20 ml of propylene carbonate, 2 ml of HCO 2 H, determination of the TOF for the first half hour, TOF calculated using factor, gas volume was measured using a 500 ml manual gas burette and analyzed by means of GC (H 2 :CO 2 =1:1).
[0000]
TABLE 4
Concentration of
Concentration of
T
TOF
No.
Fe(BF 4 ) 2 •6H 2 O [ppm]
PP 3 [ppm]
[° C.]
[h −1 ]
1
100
200
60
1922
2
100
400
60
2018
3
100
400
80
8136
4
50
400
80
9425
Example 9
Long-Term Test
[0100] Continuous decomposition of formic acid by means of Fe(BF 4 ) 2 6H 2 O and 4 eq. of PP 3 . In the experiment, 74 mmol of Fe precatalyst and 4 eq. of PP 3 were introduced into 50 ml of PC. The reaction vessel was subsequently heated to 80° C. During the experiment, 0.27±0.04 ml·min −1 of formic acid were added.
[0101] Under the experimental conditions, 335 liters of gas were able to be evolved over 16 hours at an average gas flow of 325.6 ml·min −1 . An average TOF of 5390 h −1 and a TON of 92 417 were achieved here (see FIG. 1 ).
Example 10
[0102] Production of a heterogenized SILP catalyst for the selective decomposition of formic acid.
SILPI
[0103] 0.25 mmol (84.2 mg) of Fe(BF 4 ) 2 .6H 2 O and 0.25 mmol (168 mg) of tris[(2-diphenyl-phosphino)ethyl]phosphane are introduced into a 50 ml round-bottomed flask with tap. 10 ml of THF were subsequently introduced in a countercurrent of argon and the reaction solution was stirred at room temperature for 30 minutes. 0.15 g of BMIM (1-butyl-3-methylimidazolium tetrafluoroborate) and 1.5 g of activated (600° C., 2 h, 10 −3 mbar) silica (SiO 2 ) were then added. The solution was subsequently evaporated to dryness on a rotary evaporator. Finally, the purple-colored solid was dried overnight in a high vacuum.
[0104] In an illustrative experiment, 2 ml of HCO 2 H, 5 ml of PC and 20 mg of SILPI were placed in a reaction vessel. The solution was heated to 40° C. and the gas mixture formed was analyzed by means of an automatic burette and GC (see also FIG. 2 ).
V 3h [ml] Activity [mmol
of H 2 ·h −1 ·g −1 ]
16.86 5.68 | The invention relates to a method for producing hydrogen by selective dehydration of formic acid using a catalytic system consisting of a transition metal complex of transition metal salt and at least one tripodal, tetradentate ligand, wherein the transition metal is selected from the group comprising Ir, Pd, Pt, Ru, Rh, Co and Fe. The transition metal complex can be used either as a homogeneous catalyst or a heterogenised metal complex, which has been applied to a carrier. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for making carbon fabrics, more particularly, to such a method for making carbon fabrics having high conductivity with high magnetic wave shielding efficiency by carbonizing a woven fabric, which is made by using oxidized fibers of polypropylene as raw materials, and by keeping the shrinkage of the fabric controlled below 30%.
2. Description of the Related Art
Conventional carbon fabrics are commonly formed of carbon fiber bundles by weaving. Because carbon fibers are fragile, it is not practical to directly weave carbon fibers into fabrics. Further, carbon fabrics directly woven from carbon fibers have a loose structure with big gaps in carbon fiber bundles. Therefore, regular carbon fabrics are not suitable for use to shield magnetic waves directly.
However, oxidized fibers, which are the raw material for making carbon fibers, are soft fibers having extensibility over 10%. Through a special heat treatment, fabrics of oxidized fibers can be processed into carbon fabrics of high conductivity high conductivity with high magnetic wave shielding efficiency.
SUMMARY OF THE INVENTION
It is the primary objective of the present invention to provide a method for making a carbon fabric, which is practical for making a carbon fabric of high conductivity and high density suitable for making magnetic wave shielding materials.
It is another objective of the present invention to provide a method for making a carbon fabric, which is practical for making a variety of carbon fabric products such as cloth, felt, and etc.
To achieve these objectives of the present invention, the method for making a carbon fabric comprises the steps of (a) preparing a raw fabric obtained from raw fibers by weaving, and (b) carbonizing said raw fabric into a carbon fabric; wherein the raw fibers for the raw fabric are oxidized fibers of polypropylene having a carbon content of 50 wt % at least, an oxygen content of 4 wt % at least, and a limiting oxygen index (LOI) of 35% at least.
Preferably, the carbon content of the raw fibers is over 55 wt %, the oxygen content of the raw fabrics is over 8 wt %, and the oxygen limiting index of the raw fibers is over 50%.
Further, a carbon fabric made according to the above-mentioned method has a density over 1.68 g/ml, and magnetic wave shielding efficiency over 30 dB subject to the magnetic wave having a frequency ranging from 300 MHz to 2.45 GHz.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view showing the steps of the method according to the present invention.
FIG. 2 is a picture obtained from a raw fabric through an electronic microscope according to the present invention.
FIG. 3 is a picture obtained from a carbon fabric through an electronic microscope according to the present invention (carbonization temperature at 1300° C.).
FIG. 4 is a picture obtained from a carbon fabric through an electronic microscope according to the present invention (carbonization temperature at 2500° C.).
FIG. 5 is a picture obtained from a conventional carbon fabric through an electronic microscope.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1 , the method for making a carbon fabric of the present invention is a continuous, integrated flow. At first, a raw fabric F 11 is obtained from oxidized fibers of polypropylene through a weaving process, and rolled up into a material roll F 1 . The raw fabric F 11 is then delivered in proper order through an anterior-roller set 1 and a tension wheel set 2 to a high-temperature oven 4 to receive a carbonization treatment. The treating temperature during the carbonization treatment can be maintained constant, or continuously changed, or interruptedly changed. Further, in order to prevent pyrolysis or ashing of fibers of the raw fabric F 11 during the carbonization treatment, an inert gas 3 is filled in the high temperature oven 4 for protection. After the carbonization treatment, the raw fabric F 11 has been changed to be a carbon fabric F 21 , which is then delivered through a posterior roller set 5 , and then rolled up to form a roll of finished product F 2 .
The temperature of the carbonization treatment is within 700-2500° C., and the duration of the carbonization treatment is about within 2-240 minutes. The high temperature oven 4 has two open ends, i.e., one is the air inlet and the other is the air outlet for the entrance and exit of the inert gas 3 .
The main manufacturing equipment is as described above. However, several high temperature ovens may be connected in series to run the carbonization treatment. The number and arrangement of high temperature ovens may be adjusted subject to different requirements. The temperature control during the carbonization treatment is achieved by means of a set of controllers and heating systems.
A carbon fabric made according to the aforesaid method has the density greater than 1.68 g/ml, carbon content over 70 wt %, sheet resistance below 100 Ω/cm 2 , single fifer electrical resistivity 5.56×10 −3 Ω-cm, magnetic wave shielding efficiency 30 dB at 300 MHz-3 GHz (i.e., magnetic wave shielding effect over 99.9%; relationship between dB value and magnetic wave shielding efficiency is outlined in following table I).
TABLE I
relationship between dB value and magnetic wave shielding
efficiency.
dB value
Shielding Efficiency (%)
0~10
90
10~30
90-99.9
30~60
99.9-99.9999
60~90
99.9999-99.9999999
90~120
Over 99.9999999
Example I to IV
Plain fabrics of oxidized fibers of polypropylene were used as raw fabrics, which had count 2/11.3 Nm, fabric density 27×24 (per inch), density 1.38 g/ml, carbon content 57 wt %, oxygen content 12 wt %, LOI (limiting oxygen index) 55%. FIG. 2 shows the structure of the raw fabrics when viewed through a microscope.
The prepared raw fabrics were then processed through the carbonization process lot by lot. The duration of the carbonization treatment is 10 minutes. The carbonization temperatures for Examples I to IV were 900° C., 1000° C., 1300° C., and 1500° C. respectively. During carbonization, helium was supplied and used as a protective gas, and at the same time the anterior-roller set 1 and the posterior roller set 5 were rotated at different speeds to control the shrinkage of the raw fabrics below 30%, and the tension wheel set 2 was controlled to stabilize the tension of the raw fabrics. FIG. 3 shows the microscopic structure of Example III.
Example V
The carbon fabric obtained from the aforesaid Example II was used and sent to a high temperature oven where temperature was increased at 5° C./min to 2500° C. and then maintained at 2500° C. for 2 minutes.
Comparison Samples I & II
Use same materials as the aforesaid Examples I to IV, and then carbonize the materials at 800° C. and 700° C. respectively while the other conditions maintained unchanged. The microscopic structure of Comparison Sample II is as shown in FIG. 4 .
Comparison Sample III
Comparison Sample III was a plain woven carbon fabric manufactured by Toray Industries, Inc., which is made by carbon fibers having six thousands long fibers per bundle. The microscopic structure of this material is shown in FIG. 5 (ratio of magnification: 25). Gaps among fibers are apparent.
Characteristics and magnetic wave shielding efficiency of Examples I to V and Comparison Samples 1 to 3 are as follows:
TABLE II
characteristics of carbon fabrics
Carbonization
Sheet
temperature
Carbon
Density
resistance
(° C.)
content (wt %)
(g/ml)
(Ω-cm 2 )
Example I
900
80.0
1.81
18.5
Example II
1000
85.4
1.83
41.7
Example III
1300
97.8
1.75
34.8
Example IV
1500
97.9
1.76
33.5
Example V
2500
98.3
1.90
22.8
Comparison
800
74.0
1.77
1198.4
Sample 1
Comparison
700
70.7
1.69
**
Sample 2
Comparison
Unknown
95.0
1.74
**
Sample 3
Electrical resistivity
Warp density
Weft density
(Ω-cm)
(bundle/inch)
(bundle/inch)
Example I
5.6 × 10 −3
31.0
29.8
Example II
6.9 × 10 −3
30.4
27.6
Example III
1.5 × 10 −3
30.2
27.6
Example IV
1.3 × 10 −3
31.5
28.4
Example V
6.9 × 10 −4
32.4
30.4
Comparison
1.05
30.0
28.4
Sample 1
Comparison
**
28.4
28.2
Sample 2
Comparison
4.3 × 10 −3
12
12
Sample 3
Remark 1: Electrical resistivity was measured on single fiber.
Remark 2: Comparison Sample 2 was an insulator.
Remark 3: Sheet resistance of Comparison Sample 3 not measurable.
TABLE III
Magnetic wave shielding efficiency of carbon fabrics at different
carbonization temperatures
Magnetic wave shielding efficiency at
different frequencies (dB)
300 MHz
900 MHz
1.8 GHz
2.45 GHz
Example I
34.07
35.04
36.19
37.04
Example II
32.23
30.79
33.38
33.02
Example III
46.34
43.98
49.12
48.32
Example IV
42.59
48.57
49.96
47.78
Example V
48.50
46.82
50.43
51.07
Comparison
14.46
13.02
5.79
15.56
Sample 1
Comparison
0.83
0.96
1.32
0.88
Sample 2
Comparison
0.50
0.11
0.76
0.11
Sample 3
As indicated in the aforesaid tables, conventional carbon fabrics have big gaps in fiber bundles as shown in FIG. 5 , resulting in low magnetic wave shielding efficiency (see Comparison Sample 3 in Table III). A carbon fabric made according to the present invention has a structure of high density. The arrangement of fibers of the carbon fabric according to the present invention can be anisotropic, as shown in FIGS. 3 and 4 . Therefore, the invention eliminates the problem of big gaps in fiber bundles. A carbon fabric made according to the present invention has a satisfactory magnetic wave shielding efficiency, and can be used for making heating material.
According to the aforesaid Examples I to V, the magnetic wave shielding efficiency is over 30 dB when at 300 MHz to 2.45 GHz. Preferably, the carbonization temperature is within about 900° C.-2500° C., and the time of carbonization is at about 10-100 minutes.
Further, the higher the density, carbon content, oxygen content, or limiting oxygen index of the fibers used is, the higher the carbon content and density of the carbonized carbon fabric will be. In consequence, a relatively better magnetic wave shielding efficiency can be achieved. | A carbon fabric of high conductivity and high density is formed of oxidized fibers of polypropylene. The oxidized fibers have a carbon content at least 50 wt %, an oxygen content at least 4 wt %, and a limiting oxygen index at least 35%. The carbon fabric is made by preparing a raw fabric obtained from oxidized fibers of polypropylene by weaving and then carbonizing the raw fabric. | 8 |
PRIORITY CLAIM
[0001] This application claims benefit of the priority dates of U.S. Provisional Patent Application Ser. Nos. 61/433,841 (filed Jan. 18, 2011), 61/473,378 (filed Apr. 8, 2011), and 61/526,999 (filed Aug. 24, 2011), incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention relates to mixed martial arts gloves. More particularly, the invention relates to mixed martial arts gloves that have both grappling and striking capability.
BACKGROUND
[0003] Competitive and tactical martial arts training often features injuries with open finger gloves and heavy contact because of powerful strikes. Even while making a proper fist, accidents or injuries frequently occur when a striker hits with an unorthodox angle.
[0004] What was needed was a mixed martial arts glove capable of reducing a combatant's injuries of a type that occurs during training when a combatant strikes while failing to make a proper fist or strikes with heavy contact or is struck on the wrist with heavy force during competition or tactical simulations scenarios.
SUMMARY
[0005] The glove of the present invention reduces injuries of the type that occur during training. More particularly, the glove of the present invention includes a 90 degree bent striking surface made from molded foam or layered foam for reducing injuries of the type that occur when a combatant does not make a proper fist while striking. Additionally, the glove of the present invention includes padded hammerfist and sloppy hook punch coverage. Additionally, the glove of the present invention includes wrist coverage for protection in the event a combatant is struck on the wrist during competition or tactical simulations scenarios while striking and grappling.
[0006] A first aspect of the invention is directed to an improved glove employable by a user for mixed martial arts. The glove is an open fingered type and is of a type having a dorsal pad ( 1 ) for protecting the dorsal side of the metacarpals of a user's hand against shock. Furthermore, the glove is of a type capable of assuming an open position for grappling and a clinched fist position for striking. The improvement to which a first embodiment of this first aspect of the invention is directed includes the dorsal pad ( 1 ) having a distal extension ( 2 ) with an integral bend ( 3 ) for covering the user's metacarpal/proximal phalange joints ( 14 ). The integral bend ( 3 ) conforms with the user's metacarpal/proximal phalange joints ( 14 ) with the user's hand in the clinched fist position. The integral bend ( 3 ) affords protection to the user's metacarpal/proximal phalange joints ( 14 ) while striking. The integral bend ( 3 ) is capable of unbending by unclenching the user's fingers by flexion from the clinched fist position to the open position. In a preferred mode, the improvement further includes the dorsal pad ( 1 ) having a composition of molded foam ( 5 ), with the integral bend ( 3 ) being formed by the molded foam ( 5 ). In another preferred mode, the improvement further includes the dorsal pad ( 1 ) having a composition including a first layer of low density foam ( 6 ) and a second layer of high density foam ( 7 ). The first and second layers ( 6 & 7 ) are glued to one another for forming the integral bend ( 3 ). In another preferred mode, the improvement further includes the distal extension ( 2 ) extending sufficiently for covering and protecting the user's intermediate phalanges. In another preferred mode, the improvement further includes the dorsal pad ( 1 ) extending distally for covering and protecting the user's distal phalanges.
[0007] A second embodiment of the first aspect of the invention incorporates the first embodiment, as described above and the improvement further includes the dorsal pad ( 1 ) and the integral bend ( 3 ) having an extension ( 10 ) extending laterally beyond the metacarpal/proximal phalange joint ( 14 ) of the user's index finger for affording impact protection to the lateral side of the metacarpal/proximal phalanges joint of the user's index finger against a sloop hook punch.
[0008] A third embodiment of the first aspect of the invention incorporates the first and/or second embodiment, as described above and the improvement further comprises a wrist pad ( 8 ) covering the user's wrist and affording protection to the user's carpals against shock. The wrist pad ( 8 ) has a composition including foam. The wrist pad ( 8 ) is distinct from the dorsal pad ( 1 ) and is flexibly connected thereto for affording flexibility between the wrist and hand.
[0009] A second aspect of the invention is also directed to an improved glove employable by a user for mixed martial arts. The glove is an open fingered type and is of a type having a dorsal pad ( 1 ) for protecting the dorsal side of the metacarpals of a user's hand against shock. The improvement to which a first embodiment of this second aspect of the invention is directed comprises a lateral pad ( 9 ) for providing hammer strike protection. The lateral pad ( 9 ) covers and protects the lateral side of the metacarpal/proximal phalanges joint of the user's little finger. The lateral pad ( 9 ) is flexible connected to the dorsal pad ( 1 ) and is oriented orthogonally thereto. In a preferred embodiment, the lateral strike pad has a composition that includes foam.
[0010] A third aspect of the invention is also directed to an improved glove employable by a user for mixed martial arts. The glove is an open fingered type having a dorsal pad ( 1 ) for protecting the dorsal side of the metacarpals of a user's hand against shock. The improvement to which a first embodiment of this third aspect of the invention is directed includes the dorsal pad ( 1 ) having a distal extension ( 2 ) and an integral bend ( 3 ) for covering the user's metacarpal/proximal phalange joints ( 14 ). The integral bend ( 3 ) conforms with the user's metacarpal/proximal phalange joints ( 14 ) with the user's hand in the clinched fist position for affording protection to the user's metacarpal/proximal phalange joints ( 14 ) while striking. The integral bend ( 3 ) is capable of unbending by unclenching the user's fingers by flexion from the clinched fist position to the open position. The distal extension ( 2 ) extends sufficiently for covering and protecting the user's Intermediate phalanges. The dorsal pad ( 1 ) and the integral bend ( 3 ) includes a lateral extension extending laterally beyond the metacarpal/proximal phalange joint ( 14 ) of the user's index finger for affording impact protection to the lateral side of the metacarpal/proximal phalanges joint of the user's index finger against a sloop hook punch. The improvement further comprises a wrist pad ( 8 ) and a lateral pad ( 9 ). The wrist pad ( 8 ) covers the user's wrist and affords protection to the user's carpals against shock. The wrist pad ( 8 ) has a composition including foam. The wrist pad ( 8 ) is distinct from the dorsal pad ( 1 ) and is flexibly connected to the dorsal pad ( 1 ) for affording flexibility to the wrist. The lateral pad ( 9 ) provides hammer strike protection. The lateral pad ( 9 ) covers and protects the lateral side of the metacarpal/proximal phalanges joint of the user's little finger. The lateral pad ( 9 ) is orthogonally connected to the dorsal pad ( 1 ).
[0011] A second embodiment of the third aspect of the invention incorporates the first embodiment, as described above and the improvement further includes the dorsal pad ( 1 ), including its integral bend ( 3 ), having a composition selected from the group consisting of molded foam ( 5 ) and layered foam.
[0012] A third embodiment of the third aspect of the invention incorporates the first and/or second embodiments, as described above, and the improvement further includes the dorsal pad ( 1 ) extending distally for covering and protecting the user's distal phalanges against shock.
[0013] A fourth embodiment of the third aspect of the invention incorporates the first and/or second and/or third embodiments, as described above, and the improvement further compromising an anti-microbial applied to at least one element of the glove.
[0014] A fourth aspect of the invention is directed to an improved method for manufacturing a glove employable for mixed martial arts. The improvement comprises the step of making a dorsal pad ( 1 ) having an integral bend ( 3 ) by means of a molding process, according to claim 2 .
BRIEF DESCRIPTION OF DRAWINGS
[0015] FIG. 1 illustrates a perspective view of the palm side of a prior art mixed martial arts glove.
[0016] FIG. 2 illustrates a perspective view of the dorsal side of a prior art mixed martial arts glove.
[0017] FIG. 2 illustrates a perspective view of the dorsal side of a prior art mixed martial arts glove.
[0018] FIG. 3 illustrates a phantom view of the anatomy of the human hand within the prior art mixed martial arts glove of FIG. 1 , including the carpals ( 11 ), the carpal/metacarpal joint ( 12 ), the metacarpals ( 13 ), the metacarpal/proximal phalanges joint ( 14 ), the proximal phalanges ( 15 ), the intermediate phalanges ( 16 ), and the distal phalanges ( 17 ).
[0019] FIG. 4 illustrates a perspective view of the dorsal side of a tactical mixed martial arts glove of the present invention, illustrating a distal extension ( 2 ) of the dorsal pad for protecting the intermediate phalanges, a lateral extension of the dorsal pad for protecting the metacarpal/intermediate phalange joint of the index finger ( 9 ).
[0020] FIG. 5 illustrates a perspective view of the dorsal side of the tactical mixed martial arts glove of FIG. 4 .
[0021] FIG. 6 illustrates a sectional view of the glove of FIG. 5 , illustrating molded padding in the dorsal pad and the wrist pad.
[0022] FIG. 7 illustrates the same sectional view as FIG. 6 , but illustrates layered padding in the dorsal pad.
[0023] FIG. 8 illustrates a perspective view of the dorsal side an alternative tactical mixed martial arts glove lacking a thumb sheath, but including a lateral pad ( 9 ), separate from the dorsal pad ( 1 ), for protecting the metacarpal of the user's little finger and the metacarpal intermediate phalange joint of the little finger.
[0024] FIG. 9 illustrates a perspective view of the palm side the alternative tactical mixed martial arts glove of FIG. 8 .
DETAILED DESCRIPTION
[0025] The glove of the present application is intended for use in mixed martial arts competitions. The key advancements made with this design relate to the shape of the glove and to the structure of the wrist. The shape of the foam may be reproduced in at least two ways, viz., (a) by bending the foam, or (b) by producing the foam inside a mold.
[0026] The glove of the present application provides superior hand protection by cupping the sides of the fist with padding, and by creating a bent-hand design. Prior art MMA gloves are built to cover the front of the knuckles when the hand is drawn into a fist, but do not provide adequate protection for unorthodox strikes such as the hammer fist (which strikes with the side of the fist) or the wide hook punch (which often impacts on the inside corner of the fist, near the base of the pointer finger). Using such strikes when wearing common MMA gloves can lead to serious injuries for both the striker and the person being struck. Additionally, the design of prior art MMA gloves presumes that the hand at rest should be open flat, or slightly bent. Such gloves require the wearer to draw their hand into fist before punching. The glove of the present application is designed on the premise that at rest the fighter's hand should be bent significantly, so that making a fist is easy and extending the fingers requires more effort. This bent-hand design reduces the risk of accidental finger-related injuries such as finger dislocation and eye-gouging.
[0027] The glove of the present application 1 has three preferred embodiments. In each of the preferred embodiments, the hand design is similar. The variation occurs in the wrist structure.
Example No. 1
[0028] Key features of the glove of Example No. 1 include:
1. The dorsal pad ( 1 ) incorporates bent multilayer foam that focuses the striker's impact zone on the glove. An integral bend ( 3 ) employs a layer of high density foam ( 7 ) sandwiched between two layers of low density foam ( 6 ). The integral bend ( 3 ) is achieved by gluing these layers to one another while oriented in the desired bent position. 2. Combination of layers of high density foam and soft foam increases the shock absorption of the gloves padding immensely.
a. Prior art open finger gloves have featured a “clinch your hand into a fist” design style. The glove of the present application naturally bends the user's hand into a fist position and thus the effort is not to close the hand but to open it.
3. Cupping the sides of the fist with padding is another departure from prior designs as martial arts and boxing gloves typically have padding on top of the hand not on the sides.
a. Training and fighting “accidents” are reduced by the new concepts of specially formed padding on either side of the gloves covering the sides of the fist.
4. While training against striking techniques, wrists are frequently injured by the opponent's larger bones. With the incorporation of dense foam and leather into the wrist pad ( 8 ) of the wrist strap, proper flexibility is maintained in specific angles while guarding against shock.
a. Prior art designs have incorporated wrist support but never strong padding for the wrist that was intended to be shock resistant.
[0036] Dorsal face of the gloves may be either fiat or may include split fingers. Embodiments may employ hook and loop fastening mechanism, elastic, laces, or buckles and equivalents.
[0037] The wrist strap of the glove of Example No. 1 employs flexible leather (or synthetic leather) with Velcro to secure the glove. The flexibility of this leather wrist strap is comparable to what can be found in the wrist straps of prior art MMA gloves.
[0038] In another embodiment of Example No. 1, the wrist strap employs leather (or synthetic leather) with Velcro is again used to secure the glove but additionally, the wrist is given a wrist pad ( 8 ) having shock-absorbent foam reinforcement. This internal structural difference helps maintain the wrist in proper form for punching and also helps guard the wrist against impacts from kicks and other blows.
[0039] In the third embodiment of Example No. 1, the wrist strap is replaced with boxing-style laces, which draw tight and tie together to provide a secure closure to the wrist. Although the closure system differs in this embodiment, there are some similarities in the wrist design. In all three variations, there is a flap which closes over the wrist, drawing from the inside of the wrist toward the outside.
[0040] The glove of the present invention is specially formed to encourage proper punching form and shaped to cover zones that are not ordinarily protected by gloves of this type, helping reduce injuries that occur when a combatant does not make a proper fist while striking, strikes with heavy contact, or at unorthodox angle. The glove also offers protection for the wrist, both in terms of wrist support and also in case the wrist is struck with force, e.g., by a kick.
Example No. 2
[0041] Competitive and tactical training martial arts training often features injuries with open finger gloves and heavy contact because of powerful strikes. Even while making a proper fist accidents or injuries frequently occur when a striker hits with an unorthodox angle.
[0042] The molded foam mixed martial arts (MMA) glove of Example No. 2 is specially formed to encourage proper punching form and shaped to cover zones that are not ordinarily protected by gloves of this type, helping to reduce injuries that occur when a combatant does not make a proper fist while striking, strikes with heavy contact, or at unorthodox angle. The glove also offers protection for the wrist, both in terms of wrist support and also in case the wrist is struck with force, e.g., by a kick.
[0043] Key features of the glove of Example 2 include:
1. The dorsal pad ( 1 ) employs bent molded foam ( 5 ) that focuses the striker's impact zone on the glove. 2. A combination of layers of high density foam and soft foam increases the shock absorption of the gloves padding immensely.
a. Prior art open finger gloves have featured a “clinch your hand into a fist” design style. The glove of the present application naturally bends the hand into a fist position and thus the effort is not to close the hand but to open it.
3. Cupping the sides of the fist with padding is another departure from prior designs as martial arts and boxing gloves typically have padding on top of the hand (dorsal), but not on the sides.
a. Training and fighting “accidents” are reduced by the new concepts of specially formed padding on either side of the gloves for covering the sides of the fist.
4. While training against striking techniques, wrists are frequently injured by the opponent's larger bones. With the incorporation of a wrist pad ( 8 ) having dense foam and leather into the wrist strap, proper flexibility is maintained in specific angles while guarding against shock.
a. Prior art designs show that MMA glove have incorporated wrist support but never strong padding for the wrist that was intended to be shock resistant.
[0051] The gloves of Example No. 2 have split fingers but could readily be changed to have the same elements with a flat face. The present embodiment incorporates a hook and loop fastening mechanism but can easily be modified to use elastic, laces, buckles etc.
Example No. 3
[0052] The advanced design of Example No. 3 helps reduce injuries during tactical training. Key features of the glove of Example 3 include:
1. Five sided padding, including the front fist ( 2 ), back of hand ( 1 ), outside and inside of fist ( 9 & 10 ), and bottom edge of fist ( 8 ), minimizes damage from fractures and cuts to both the striker and opponent from straight punches, outside and vertical hook punches, back-fist and hammer-fist strikes. 2. Wrist support incorporates a closed cell foam wrist pad ( 8 ) that supports and aligns the wrist while protecting against injury from rolling the wrist, kicks or incidental contact. 3. Structure and curvature of glove gives hand natural form for safe striking. 4. Bent multi-layer multi-density foam guides the hand to rest in a bent position guarding against accidental eye-pokes and injury to the hand because of improper punching technique. This padding is also designed to focus the target area of the glove and has an extra layer of high-density foam covering the knuckles for maximum protection. 5. Specially designed finger loops which do not impair gripping and grappling practice while allowing the practitioner to form a clinched fist for striking. 6. Velcro wrist strap secures wrist while striking. 7. Heavyweight open-handed training glove for tactical, martial arts and weapon training. 8. Double-stitching is used as needed to protect seams. 9. Wipeable interior surface for cleanliness. 10. Interior and exterior materials are treated with a unique combination of germ killing agents proven effective against infectious microorganisms—including several that are of great concern to the medical community and governments including Staph, MRSA, Ringworm, and others. The formula is applied to the materials at the factory producing a long-term bond that strengthens material and defeats the colonization of microbes seeking attachment and growth on surfaces.
[0063] Preferred Materials and Alternate Materials:
[0064] The glove is constructed using an advanced, man-made leather (herein referred to as MML), composed of a non-woven fabric. It consists of ultra-fine fibers, as fine as 0.05 micron to imitate collagen fiber bundles. The bundles are impregnated with polyurethane to improve flexibility and conformability. The fabric is three times stronger than leather, requiring only a third of real leather's weight to achieve equal tear strength. More durable and consistent than real leather, the material resists abrasion better, will not dry out or become brittle, and does not wear down after years of use. If man-made leather matching these specifications is not available, then to ensure quality, the glove can be made from Grade A natural leather.
[0065] Multiple shock-absorbent cushioning materials are used in this design, including a polymer composite containing a chemically engineered dilatant to function as an energy absorber. This advanced material, used to absorb the heaviest impacts, is lightweight, soft and flexible but on shock locks together to absorb and disperse energy, before instantly returning to its flexible state. If this advanced material is not available, a thicker layer of dense, closed cell foam can be used in its place to ensure user safety and product longevity.
[0066] The textile or surface layer may be treated with an antimicrobial agent to reduce odor-causing and/or pathogenic microorganisms. Examples of such antimicrobial agents include: silane functionalized quaternary amines such as Microbe Shield™ available from AEGIS Environments; colloidal silver solutions such as Silpure™ available from Thompson Research Associates, Canada, silver chelated polymer solutions such as SilvaDur™ available from Rohm & Haas; biguanides such as polyhexamethylene biguanide sold under the trade names Vantocil™ and Cosmocil™ available from Arch Chemicals; and a formulation sold under the name of GermPro™ available from GermPatrol LLC, Largo, Fla.
[0067] Selected Measurement:
[0068] Elastic Wrist Band:
M—1.5″×3.25″ L—1.5″×3.25″ XL—1.5″×3.25″
Wrist cuff:
M—5.5″×3.5″ L—6″×3.5″ XL—6″×4″
[0075] Thumb Guard:
[0076] Exterior MML material shell, felt interior:
M—6″×2″ L—6.5″×2″ XL—7″×2.5″
[0080] Dense Sponge—0.75″ thick:
M—2″ long, 2″ across at thumb-base, 1.5″ across at top L—2″ long, 2″ across at thumb-base, 1.5″ across at top XL—2.5″ long, 2.5″ across at thumb-base, 1.5″ across at top
[0084] Light Sponge, 0.25″ thick:
M—4″ long, 2″ across at thumb-base, 1″ across at wrist L—4″ long, 2″ across at thumb-base, 1″ across at wrist XL—5″ long, 2.5″ across at thumb-base, 1″ across at wrist
[0088] Main Padding Area:
90° curve from top of knuckles to fingers
[0090] 3 Layered Padding:
Outer layer: Sponge Foam Middle Layer Dense, Closed Cell Foam Inner Layer Sponge Foam 1.5″ Thick at Knuckles 1″ Thick at Fingers and at Wrist Cuff
[0096] From Top of Wrist Cuff to Fingers:
M—8.875″ L—9″ XL—9″
[0100] From Top of Wrist Cuff to Top of Knuckles:
M—3.5″ L—4″ XL—4″
[0104] From top of knuckles to fingers:
M—4″ L—4″ XL—4″
[0108] Across Knuckles:
M—4.5″ L—5″ XL—5″
[0112] Across Fingers and at Top of Wrist:
M—3.5″ L—4″ XL—4″
[0116] Side of Fist Padding:
Foam 0.5″ thick M—1.125″×3″ L—1,5″×3″ XL—1.5×3″
[0121] Finger Loops:
[0122] Material 0.0625″ thick is made of MML material and felt stitched together. Each loop double-stitched in place. Material used to make four Finger Loops:
M—approximately 9″×2.25″ 4″ across Glove, 1″ per finger, each loop extends out 1.25″ L—approximately 10″×2.25″ 4.5″ across Glove, 1″ per finger, each loop extends out 1.25″ XL—approximately 12″×2.5″ 5″ across Glove, 1.125″ per finger, each loop extends out 1.25″
[0126] Width of Finger Loops:
M—0.75″ at bottom of finger 2.25″ at top of finger. L—0.75″ at bottom of finger 2.25″ at top of finger. XL—0.875″ at bottom of finger 2.5″ at top of finger.
[0130] Thumb Loop:
[0131] Material 0.0625″ thick is made of MML material and felt stitched together. Material used to make Thumb Loop:
M—approximately 2″×3″, 1.75″ across Thumb Guard, loop extends out 0.75″ L—approximately 2″×3″, 1.75″ across Thumb Guard, loop extends out 0.75″ XL—approximately 2.25″×3″, 2 ″ across Thumb Guard, loop extends out 1″
[0135] Width of Thumb Loop:
M—0.75″ at bottom of thumb, 2″ at top outside, 1.5″ at top inside L—0.75″ at bottom of thumb, 2″ at top outside, 1.5″ at top inside XL—0.875″ at bottom of thumb, 2.5″ at top outside, 1.75″ at top inside
[0139] Dimensions of Wrist Strap:
M—9.25″×2.25″ L—9.5″×2.25″ XL—9.5″×2.25″
[0143] Dimensions of Velcro Strip on Top of Wrist Cuff:
M—2″×5″ L—2″×5.5″ XL—2″×5.5″
[0147] Velcro Strip on Bottom of Wrist Strap:
M—2″×5.5″ L—2″×5.5″ XL—2″×5.75″
[0151] Soft Piping:
M— 50 ″ L—51″ XL—52″ | A glove employable for mixed martial arts, including striking and grappling, employs a dorsal pad having distal and lateral extensions with an integral bend for covering both the dorsal and lateral sides of the user's metacarpal/proximal phalange joints. The integral bend conforms with the user's metacarpal/proximal phalange joints with the user's hand in the clinched fist position. The glove affords protection to the user's metacarpal/proximal phalange joints while striking. On the other hand, the integral bend is capable of easily unbending to an open position for grappling. The integral bend is unbent by unclenching the user's fingers by flexion from the clinched fist position to the open position. The glove also includes a wrist pad for protecting the wrist against heavy strikes. | 0 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/170,859, filed Jun. 4, 2015, the entire content of which is herein incorporated by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] (NOT APPLICABLE)
BACKGROUND AND SUMMARY
[0003] The invention relates to a fantasy sports team league (FSTL) where multiple teams are drafted to be on the FSTL player's “roster” for the day, week, or season.
[0004] This FSTL is team-centered, as opposed to leagues that focus on the performance of individual players. Since many sports leagues have many teams (e.g. college football currently has 128 in the FBS alone, Division I college basketball has 350 teams, etc.), and because the players in leagues like college football and college basketball are so numerous (FBS college football has around 15,000 players while Division I college basketball has over 5,000), and since teams can change drastically from year-to-year, it is often too difficult for the average FSTL player to come to well-reasoned predictions about individual players—especially those playing for teams outside of the FSTL player's sphere of interest (e.g. his/her local team, conference preference, alma mater, etc.). Therefore, instead of haphazardly selecting individual players, FSTL players can utilize team research to build a fantasy roster of entire teams to compete against the rosters of opposing FSTL players.
[0005] In an exemplary embodiment, a method of administering a fantasy sports team league includes the steps of (a) establishing a player salary cap; (b) conducting a draft by enabling players to select teams or team characteristics from a list of game matchups, each team or team characteristic being assigned a cost and a point value based on each team's chance of winning, wherein the players are required to keep a total cost of the selected teams below the player salary cap; and (c) after the game matchups have been played, awarding the point value to the players for each winning team or team characteristic selected by each of the players.
[0006] Step (a) may be practiced based on a number of team or team characteristic offerings and the cost of each team or team characteristic. In step (b), the cost and point value for each team or characteristic may be dependent on the team's or characteristic's chance of winning. In this context, the method may also include determining the team's chance of winning by using moneyline odds at a specific time before the draft, removing a vigorish added in the moneylines to arrive at a result, and converting the result to a percentage. The team characteristics may comprise at least one of a team's offense and a team's defense. Steps (a)-(c) may be practiced weekly over an entire season, and the method may further include the step of determining the fantasy sports team league winner based on points accumulated over the entire season. The team characteristics may include a number of wins over an entire season, where the cost and point value for each team may be determined according to a number of games each team may be projected to win.
[0007] In another exemplary embodiment, a computer system for administering a fantasy sports team league includes at least one user computer running a computer program that requests and processes information according to registration information input by a player; and a system server running a server program, where the at least one user computer and the system server are interconnected by a computer network. The system server administers the fantasy sports team league by (a) establishing a player salary cap, (b) in conjunction with the at least one user computer, conducting a draft by enabling players to select teams or team characteristics from a list of game matchups, each team or team characteristic being assigned a cost and a point value based on each team's chance of winning, where the players are required to keep a total cost of the selected teams below the player salary cap, and (c) after the game matchups have been played, the system server awarding the point value to the players for each winning team or team characteristic selected by each of the players.
[0008] In another exemplary embodiment, a computer program is embodied on a computer-readable medium for administering the fantasy sports team league.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] These and other aspects and advantages will be described in detail with reference to the accompanying drawings, in which:
[0010] FIG. 1 is an exemplary chart of weekly matchups;
[0011] FIG. 2 is a chart showing exemplary player rosters;
[0012] FIG. 3 shows charts with exemplary results after the matchups are completed;
[0013] FIGS. 4A and 4B show teams and projected wins for a season-long major-league baseball contest;
[0014] FIGS. 5 and 6 show exemplary rosters and results, respectively, for the season-long major league baseball contest; and
[0015] FIG. 7 is a schematic diagram of an exemplary computer system.
DETAILED DESCRIPTION OF THE INVENTION
[0016] After registration and (possibly) payment are verified, the FSTL player is logged-in to his/her personal dashboard. The dashboard contains account settings, notifications, history, etc. Among other things, it allows for username and password changes, displays league(s) status, provides notifications, allows for team/FSTL player customization (logos, avatars, colors, etc.), allows for changes to payment options, allows for the filtering/searching for upcoming games, etc.
[0017] When entering a contest, the FSTL player selects the type of play (free or money—at tiered levels of entry fee and prizes awarded), the league (conference, inter-conference, national, etc.), the number of FSTL players (tournament, head-to-head, three-player, four-player, etc.) and its duration: daily, weekly, or season-long.
[0018] In the case of a money league, the FSTL player pays the entry fee for the given contest.
Draft Procedures
[0019] Depending on the contest, a “salary cap” is provided. It is the same for every FSTL player in the given contest, and the amount is dependent on the number of team offerings and the cost of each team (which is dependent upon the likelihood of each team winning its matchup, unless it is a season-long contest). After a contest is filled, the draft will begin at its designated time. There will be options for auto-drafting specifications. Draft order is assigned randomly. Each FSTL player takes it in turn to “draft” one team at a time. The participants will see all the matchups for their contest. The matchups will contain teams with their likelihood of winning the game. The likelihood (i.e. the probability of victory) may be determined using any suitable methodology, which may be dependent on the sport. An exemplary “Chance of Winning” for college football may be determined by taking “moneyline” odds (at a specific point in time before the draft), removing the vigorish that is added to the moneylines, and then converting that number to a percentage. The sum of the “Chance of Winning” percentages for opposing teams in a single matchup (when the outcome is binary: winning or losing) is 100%. The amount paid for each team will depend on that team's likelihood of winning the game. The amount of contest points won for each team's victory will also be dependent on the team's likelihood of winning the game. For example, a college football head-to-head (two-player) weeklong Southeastern Conference contest might see the following rules and the chart of FIG. 1 :
[0020] RULES: (1) EACH PLAYER MUST CHOOSE AT LEAST FOUR TEAMS; (2) NO FSTL PLAYER CAN CHOOSE BOTH TEAMS INVOLVED IN A SINGLE MATCHUP (i.e. both sides of a game); (3) THE SALARY CAP IS $950; (4) TIES ARE BROKEN: FIRST, BY NUMBER OF VICTORIES; SECOND, BY REMAINING MONEY (under the salary cap).
[0021] (In addition to the data in FIG. 1 , research on each team's performance will be available, as well as the option to see expert assessments of each team, matchup, etc.)
[0022] The team less likely to win the game always costs $100 against the salary cap, but if they win, the FSTL player is rewarded with more contest points.
[0023] Continuing this example, two FSTL players, Charlie and Jonah, are playing head-to-head. See FIG. 2 . For his four teams, Charlie paid $885. He was $65 under his salary cap. For his six teams, Jonah paid $852. He was $98 under his salary cap. The results are shown in FIG. 3 .
[0024] Charlie won the contest, since his roster of schools accumulated 365 points, while Jonah's roster accumulated 200 contest points. Therefore, Charlie would receive his contest prize winnings automatically, and he would be able to view and access those winnings through his dashboard.
[0025] One alternative to the basic format (outlined above) would be the drafting of statistical categories for entire teams. For example, a FSTL player would pay for Alabama's rushing offense, Washington State's passing offense, TCU's rush defense, Ohio State's passing defense, UCLA's placekicking, etc.
[0026] No matter the alternative, the concept of drafting the performance of an entire team (rather than individuals on those teams) remains constant.
[0027] The use of betting data (i.e. moneyline odds, futures bets (for things like season win totals), proposition bets (for things like rushing yards, home runs, three-pointers, etc.)) to convert to fantasy sports winning percentages and (therefore,) prices is equally significant to the team aspect of the described embodiments. The methodology uses betting data (without the vigorish) to calculate all probabilities/likelihoods of any (winning) outcome.
[0028] Another example of how this method of betting data conversion might work for team characteristics is:
[0029] Alabama: (1) will rush for over 150 yards—Cost $400 to win $100; or (2) will not rush for over 150 yards—Cost $100 to win $400.
[0030] Clemson: (1) will rush for over 200 yards—Cost $300 to win $100; or (2) will not rush for over 200 yards—Cost $100 to win $300.
[0031] In this instance, fantasy sports players are “drafting” team statistical scenarios like total number of rushing yards (or runs to be scored, three-pointers to be made, etc.). In every case, the potential win percentage and, therefore, the prices, would be determined by vigorish-less betting data.
Season-Long Contests
[0032] Version 1: A season-long college football contest would follow the same format as the above example with the only difference being that teams are drafted anew each week. The FSTL players carry their cumulative contest point-totals with them from week to week. At the end of the entire season, the contest winner is determined by the greatest total number of contest points won for all weeks combined. This version can be played with or without the ability to carry over remaining salary cap money from the previous week(s) to the current weekly draft.
[0033] Version 2: Drafting teams that earn contest points for every win. Team price is based on predetermined, projected team-win totals: the more wins a team is projected to win, the more expensive the team. For example, a four-player regular season-long major league baseball contest might see the following rules and the charts in FIGS. 4A and 4B :
[0034] RULES: (1) EACH PLAYER MUST CHOOSE AT LEAST FOUR TEAMS; (2) NO TEAM CAN BE DRAFTED BY MORE THAN ONE FSTL PLAYER; (3) THE SALARY CAP IS $38,000; (4) TIES ARE BROKEN BY REMAINING MONEY (under the salary cap).
[0035] (In addition to the data shown in FIGS. 4A and 4B , for each team, research, expert assessments, etc., will be available.)
[0036] Continuing this example, four FSTL players, Ben, Sam, Dave, and Casey are playing in a season-long contest (see FIG. 5 ). Ben was $400 under the salary cap. Sam was $1,950 under the salary cap. Dave was $1,750 under the salary cap. Casey was $350 under the salary cap. The results are shown in FIG. 6 .
[0037] Casey won the contest, since his roster of teams accumulated 393 points. At the season's conclusion, Casey would receive his contest prize winnings automatically, and he would be able to view and access those winnings through his dashboard.
[0038] Both season-long versions (or multi-week versions) allow for a variety of tournament play. For instance, 8, 16, 32, etc. FSTL players can be randomly placed in brackets going head-to-head in pairs as they win their way through the brackets over a designated period of time (ranging from multiple days to season-long) until one champion is left standing.
[0039] All formats are applicable to all sports.
[0040] The administration of a fantasy sports team league described with reference to FIGS. 1-6 is preferably a browser-based system in which a program running on a user's computer (the user's web browser) requests information from a server program running on a system server. The system server sends the requested data back to the browser program, and the browser program then interprets and displays the data on the user's computer screen. The process is as follows:
[0041] 1. The user runs a web browser program on his/her computer or an app on a wireless device.
[0042] 2. The user connects to the server computer (e.g., via the Internet). Connection to the server computer may be conditioned upon the correct entry of a password as is well known.
[0043] 3. The user requests a page from the server computer. The user's browser sends a message to the server computer that includes the following:
the transfer protocol (e.g., http://); and the address, or Uniform Resource Locator (URL).
[0046] 4. The server computer receives the user's request and retrieves the requested page, which is composed, for example, in HTML (Hypertext Markup Language).
[0047] 5. The server then transmits the requested page to the user's computer.
[0048] 6. The user's browser program receives the HTML text and displays its interpretation of the requested page.
[0049] Thus, the browser program on the user's computer sends requests and receives the data needed to display the HTML page on the user's computer screen. This includes the HTML file itself plus any graphic, sound and/or video files mentioned in it. Once the data is retrieved, the browser formats the data and displays the data on the user's computer screen. Helper applications, plug-ins, and enhancements such as Java™ enable the browser, among other things, to play sound and/or display video inserted in the HTML file. The fonts installed on the user's computer and the display preferences in the browser used by the user determine how the text is formatted.
[0050] If the user has requested an action that requires running a program (e.g., a search), the server loads and runs the program. This process usually creates a custom HTML page “on the fly” that contains the results of the program's action (e.g., the search results), and then sends those results back to the browser.
[0051] Browser programs suitable for use in connection with the account management system of the present invention include Mozilla Firefox® and Internet Explorer available from Microsoft® Corp.
[0052] While the above description contemplates that each user has a computer running a web browser, it will be appreciated that more than one user could use a particular computer terminal or that a “kiosk” at a central location (e.g., a cafeteria, a break area, etc.) with access to the system server could be provided.
[0053] It will be recognized by those in the art that various tools are readily available to create web pages for accessing data stored on a server and that such tools may be used to develop and implement the system described below and illustrated in the accompanying drawings.
[0054] FIG. 7 generally illustrates a computer system 201 suitable for use as the client and server components of the described system. The computer system 201 may be embodied in the form of a desktop or laptop computer or alternatively in the form of a wireless handheld device such as a smartphone, tablet or the like. It will be appreciated that the client and server computers will run appropriate software and that the client and server computers may be somewhat differently configured with respect to the processing power of their respective processors and with respect to the amount of memory used. Computer system 201 includes a processing unit 203 and a system memory 205 . A system bus 207 couples various system components including system memory 205 to processing unit 203 . System bus 207 may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. System memory 205 includes read only memory (ROM) 252 and random access memory (RAM) 254 . A basic input/output system (BIOS) 256 , containing the basic routines that help to transfer information between elements within computer system 201 , such as during start-up, is stored in ROM 252 . Computer system 201 further includes various drives and associated computer-readable media. A hard disk drive 209 reads from and writes to a (typically fixed) magnetic hard disk 211 ; a magnetic disk drive 213 reads from and writes to a removable “floppy” or other magnetic disk 215 ; and an optical disk drive 217 reads from and, in some configurations, writes to a removable optical disk 219 such as a CD ROM or other optical media. Hard disk drive 209 , magnetic disk drive 213 , and optical disk drive 217 are connected to system bus 207 by a hard disk drive interface 221 , a magnetic disk drive interface 223 , and an optical drive interface 225 , respectively. The drives and their associated computer-readable media provide nonvolatile storage of computer-readable instructions, SQL-based procedures, data structures, program modules, and other data for computer system 201 . In other configurations, other types of computer-readable media that can store data that is accessible by a computer (e.g., magnetic cassettes, flash memory cards, digital video disks, Bernoulli cartridges, random access memories (RAMs), read only memories (ROMs) and the like) may also be used.
[0055] A number of program modules may be stored on the hard disk 211 , removable magnetic disk 215 , optical disk 219 and/or ROM 252 and/or RAM 254 of the system memory 205 . Such program modules may include an operating system providing graphics and sound APIs, one or more application programs, other program modules, and program data. A user may enter commands and information into computer system 201 through input devices such as a keyboard 227 and a pointing device 229 . Other input devices may include a microphone, joystick, game controller, satellite dish, scanner, or the like. These and other input devices are often connected to the processing unit 203 through a serial port interface 231 that is coupled to the system bus 207 , but may be connected by other interfaces, such as a parallel port interface or a universal serial bus (USB). A monitor 233 or other type of display device is also connected to system bus 207 via an interface, such as a video adapter 235 . In addition, a speaker 237 or other type of audio output device is connected to the system bus 207 via an audio interface, such as a sound card 239 .
[0056] The computer system 201 may also include a modem or broadband or wireless adapter 234 or other means for establishing communications over the wide area network 236 , such as the Internet. The modem 234 , which may be internal or external, is connected to the system bus 207 via the serial port interface 231 . A network interface 241 may also be provided for allowing the computer system 201 to communicate with a remote computing device 250 via a local area network 258 (or such communication may be via the wide area network 236 or other communications path such as dial-up or other communications means). The computer system 201 will typically include other peripheral output devices, such as printers and other standard peripheral devices.
[0057] As will be understood by those familiar with web-based forms and screens, users may make menu selections by pointing-and-clicking using a mouse, trackball or other pointing device, or by using the TAB and ENTER keys on a keyboard. For example, menu selections may be highlighted by positioning the cursor on the selections using a mouse or by using the TAB key. The mouse may be left-clicked to select the selection or the ENTER key may be pressed. Other selection mechanisms including voice-recognition systems, touch-sensitive screens, etc. may be used, and the invention is not limited in this respect.
[0058] The method and system of the described embodiments may be implemented using a flexible, self-referential table that stores data. The table may store any type of data, both structured and unstructured, and provides an interface to other application programs. The table may include a plurality of rows and columns, where each row has an object identification number (OID), and each column also has an OID. A row corresponds to a record and a column corresponds to a field such that the intersection of a row and a column may comprise a cell that may contain data for a particular record related to a particular field. An exemplary self-referential table is described in U.S. Pat. No. 6,151,604, the contents of which are hereby incorporated by reference.
[0059] While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. | In a fantasy sports team league, a player salary cap is established and a draft is conducted by enabling players to select teams or team characteristics from a list of game matchups. Each team or team characteristic is assigned a cost and a point value based on each team's chance of winning. The players are required to keep a total cost of the selected teams below the player salary cap. After the game matchups have been played, the point value for each winning team or team characteristic selected by each of the players is awarded. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This patent application is based on and claims priority pursuant to 35 U.S.C. §119 to Japanese Patent Application No. 2012-000931, filed on Jan. 6, 2012, in the Japan Patent Office, the entire disclosure of which is hereby incorporated by reference herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a communications apparatus and method, and more particularly to an apparatus that facilitates switching from wired LAN to wireless LAN and vice versa.
2. Description of the Background Art
Conventionally, in communications apparatuses that include a wired communication function (wired LAN) and a wireless communication function (wireless LAN), configurations such as using both wired LAN and wireless LAN together, and enabling only one of wired LAN or wireless LAN exclusively to cut energy consumption have been conceived and are well-known.
A technology of a network terminal that includes wired LAN and wireless LAN and switches between wired LAN and wireless LAN automatically by detecting the connection status of a wired LAN cable solely by monitoring the insertion and the removal of the wired LAN cable to save time and effort has been proposed (e.g., JP-H10-164114-A.)
In the technology described in JP-H10-164114-A, switching between wired LAN and wireless LAN is determined by detecting the connection status of the wired LAN cable. However, it cannot be determined which one, wired LAN or wireless LAN, is to be enabled based on multiple different operating states of the apparatus.
SUMMARY OF THE INVENTION
The present invention provides a novel communications apparatus that includes a plurality of wired LAN functions and wireless LAN functions and facilitates determining which network interface is to be enabled more flexibly.
More specifically, the present invention provides a communications apparatus that switches between wired LAN functions and wireless LAN functions and includes a network interface control unit that enables and disables wired LAN and wireless LAN, a wired LAN communication availability status acquisition unit that detects that there is a change in the status of communication availability of wired LAN and acquires the status of communication availability of wired LAN, and a network interface determining unit that enables only one network interface from communication availability status of wired LAN acquired by the wired LAN communication availability status acquisition unit and a plurality of operating states of the apparatus.
In the present invention, in the communications apparatus that includes a plurality of wired LAN functions and wireless LAN functions, it can be flexibly determined which network interface is to be enabled by considering not only connection status of wired LAN cable but also a plurality of operating states of the apparatus in case only one network interface is enabled exclusively.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
A more complete appreciation of the disclosure and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings.
FIG. 1 is a diagram illustrating a software configuration according to an embodiment of the present invention.
FIG. 2 is a chart correlating wired LAN communication availability and enabled network interface according to an embodiment of the present invention.
FIG. 3 is a chart correlating examples of network settings and enabled network interface.
FIG. 4 is a diagram illustrating examples of possible power statuses and network communication availability in each power status.
FIGS. 5A , 5 B, 5 C, and 5 D are charts that illustrate which network interface gets enabled when change in the status of wired LAN communication availability, change in network settings, and change of the power status occurs as the switching event of network interface occurs.
FIG. 6 is a flowchart illustrating changing which network interface gets enabled depending on the setting of network interface.
FIG. 7 is a flowchart illustrating checking the power status before determining which network interface ultimately gets enabled.
FIG. 8 is a flowchart illustrating checking whether or not device error occurs in the network interface which is to be enabled.
FIG. 9 is a flowchart illustrating determining whether or not network interface is switched after waiting for a predefined period of time in case of detecting change in the status of wired LAN communication availability.
DETAILED DESCRIPTION OF THE INVENTION
In describing preferred embodiments illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the disclosure of this patent specification is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner and achieve a similar result.
An embodiment of the present invention will be described in detail below with reference to the drawings.
FIG. 1 is a diagram illustrating a software configuration in this embodiment. A network interface control unit 2 , a wired LAN communication availability acquisition unit 3 , a network setting acquisition unit 4 , a power status acquisition unit 5 , an error status acquisition unit 6 , and a time measuring unit 7 are connected to a network interface determining unit 1 .
The network interface determining unit 1 determines which network interface gets enabled by considering wired LAN communication availability status, network setting, power status of the apparatus, and error status of the apparatus.
The network interface control unit 2 allocates IP addresses for wired LAN and wireless LAN so that they can execute IP communication (enables network interface), and switches wired LAN and wireless LAN to the status not available for IP communication (disables network interface).
The wired LAN communication availability acquisition unit 3 detects any change in the status of wired LAN communication availability. Also, the wired LAN communication availability acquisition unit 3 acquires the status of wired LAN communication availability. The network setting acquisition unit 4 detects change in network settings. Also, the network setting acquisition unit 4 acquires network settings set in the apparatus. It should be noted that network settings are user settings necessary for network communication, such as DHCP availability, IP address setting, subnet mask, and SSID.
The power status acquisition unit 5 detects change in the power status of the apparatus. Also, the power status acquisition unit 5 acquires the power status of the apparatus. The error status acquisition unit 6 detects any error that occurs in the apparatus. The time measuring unit 7 determines that a predefined period of time has elapsed.
FIG. 2 is a chart correlating wired LAN communication availability and enabled network interface. More specifically, FIG. 2 shows an example of the logic used in determining which network interface gets enabled depending on wired LAN communication availability in the communications apparatus that includes a plurality of network interfaces. In FIG. 2 , an example in which wired LAN gets enabled if wired LAN communication is available and wireless LAN gets enabled if wired LAN communication is not available is shown. The wired LAN communication availability acquisition unit 3 detects change in the status of wired LAN communication availability and acquires the status of wired LAN communication availability with reference to an example such as that shown in FIG. 2 , and the network interface determining unit 1 switches network interface.
FIG. 3 is a chart correlating examples of network settings and enabled network interface. FIG. 3 shows an example of settings for deciding priority to determine which network interface gets enabled in the communications apparatus that includes a plurality of network interfaces. How network interface is switched is determined by settings set by a user. The network setting acquisition unit 4 detects change in the network settings and acquires the network settings, and the network interface determining unit determines whether or not it switches network interface.
Switching network interface is determined automatically only if wired LAN and wireless LAN are used exclusively, so in case a user wants to keep on using either network, the unintended switching process of network interface is not executed even if the user connects or removes a wired LAN cable for greater convenience.
FIG. 4 is a diagram illustrating examples of possible power statuses and network communication availability in each power status. The power status acquisition unit 5 detects change in the power status of the apparatus and acquires the power status with considering power status such as shown in FIG. 4 , and the network interface determining unit 1 determines whether or not network interface is switched.
Switching process of network interface is not executed needlessly since a situation in which the network interface cannot be switched due to the power status of the apparatus after trying to switch network interface when the status of wired LAN communication availability is changed does not occur, and that improves efficiency.
Also, switching to wired LAN or wireless LAN is not executed needlessly in a situation in which the network interface cannot be switched due to the power status or the apparatus after trying to switch from wireless LAN to wired LAN or from wired LAN to wireless LAN does not occur, and that improves efficiency.
FIGS. 5A , 5 B, 5 C, and 5 D are charts that illustrate which network interface gets enabled when change in the status of wired LAN communication availability, change in network settings, and change of the power status occurs as the switching event of network interface.
Other network switching events in addition to events described above are conceivable. Determining whether or not network interface is switched automatically with reference to a plurality of conditions and switching network interface automatically if necessary is the technical feature of this embodiment.
FIG. 6 is a flowchart illustrating changing which network interface gets enabled depending on the setting of network interface.
If the status of wired LAN communication availability is changed after a network switching event occurs (step S 1 ), the wired LAN communication availability acquisition unit 3 detects the status of wired LAN communication availability (S 2 ). If the network setting is changed, the network setting acquisition unit 4 detects change in the network settings (S 3 ) and determining which network interface gets enabled is started (S 4 ).
The network setting acquisition unit 4 sets network setting (S 5 ). If the network setting set in the apparatus is wired LAN (S 6 ), the network interface determining unit 1 determines whether or not wired LAN is available by checking the wired LAN communication availability acquisition unit 3 (S 10 ). If wired LAN is available (YES in S 10 ), the network interface control unit 2 enables wired LAN (S 11 ). If wired LAN is not available (NO in S 10 ), the process returns to the beginning.
If the network setting is prioritizing wired LAN (S 7 ), the network interface determining unit 1 determines whether or not wired LAN is available by checking the wired LAN communication availability acquisition unit 3 (S 12 ). If wired LAN is available (YES in S 12 ), the network interface control unit 2 enables wired LAN (S 11 ). If wired LAN is not available (NO in S 10 ), the network interface control unit 2 enables wireless LAN (S 13 ).
If the network setting is set to wireless LAN (S 8 ), the network interface control unit 2 enables wireless LAN (S 13 ). If the network setting is set to disable (S 9 ), the process returns to the beginning.
FIG. 7 is a flowchart illustrating checking the power status before determining which network interface ultimately gets enabled.
If the status of wired LAN communication availability is changed after network switching event occurs (S 21 ), the wired LAN communication availability acquisition unit 3 detects the status of wired LAN communication availability (S 22 ). If the network setting is changed, the network setting acquisition unit 4 detects change in the network settings (S 23 ). The power status acquisition unit 5 detects change in the power status if the power status is changed (S 24 ), and determining which network interface gets enabled is started (S 25 ).
The network setting acquisition unit 4 sets network setting (S 26 ). If the network setting set in the apparatus is wired LAN (S 27 ), the network interface determining unit 1 determines whether or not wired LAN is available by checking the wired LAN communication availability acquisition unit 3 (S 31 ). If wired LAN is not available (NO in S 31 ), the process returns to the beginning.
If wired LAN is available (YES in S 31 ), the network interface determining unit 1 determines whether or not the power status is one in which wired LAN can be enabled by checking the power status acquisition unit 5 (S 32 ). If the power status is one in which wired LAN can be enabled (YES in S 32 ), the network interface control unit 2 enables wired LAN (S 33 ). Otherwise (NO in S 32 ), the process returns to the beginning.
If the network setting is set to prioritizing wired LAN (S 28 ), the network interface determining unit 1 determines whether or not wired LAN is available by checking the wired LAN communication availability acquisition unit 3 (S 34 ). If wired LAN is available (YES in S 34 ), the network interface determining unit 1 determines whether or not the power status is one in which wired LAN can be enabled by checking the power status acquisition unit 5 (S 32 ). The following steps are the same as described above.
If wired LAN is not available (NO in S 34 ), the network interface determining unit 1 determines whether or not the power status is one in which wireless LAN can be enabled by checking the power status acquisition unit 5 (S 35 ). If the power status is one in which wireless LAN can be enabled (YES in S 35 ), the network interface control unit 2 enables wireless LAN (S 36 ). Otherwise (NO in S 35 ), the process returns to the beginning.
If the network setting is set to wireless LAN (S 29 ), the network interface determining unit 1 determines whether or not wireless LAN is available by checking the power status acquisition unit 5 (S 35 ). The following steps are the same as described above. If the network setting is set to disable (S 30 ), the process returns to the beginning.
FIG. 8 is a flowchart illustrating checking whether or not device error occurs in the network interface which is to be enabled. The same steps as in FIG. 7 are given the same reference numerals and a description thereof is omitted.
The network setting acquisition unit 4 sets network setting (S 26 ). If the network setting set in the apparatus is wired LAN (S 27 ), the network interface determining unit 1 determines whether or not wired LAN is available by checking the wired LAN communication availability acquisition unit 3 (S 31 ). If wired LAN is not available (NO in S 31 ), the process returns to the beginning. If wired LAN is available (YES in S 31 ), the network interface determining unit 1 determines whether or not device error occurs in wired LAN by checking the error status acquisition unit 6 (S 41 ). If device error occurs in wired LAN (NO in S 41 ), the process returns to the beginning.
If device error does not occur in wired LAN (YES in S 41 ), the network interface determining unit 1 determines whether or not the power status is one in which wired LAN can be enabled by checking the power status acquisition unit 5 (S 32 ). If the power status is one in which wired LAN can be enabled (YES in S 32 ), the network interface control unit 2 enables wired LAN (S 33 ). Otherwise (NO in S 32 ), the process returns to the beginning.
If the network setting is set to prioritizing wired LAN (S 28 ), the network interface determining unit 1 determines whether or not wired LAN is available by checking the wired LAN communication availability acquisition unit 3 (S 34 ). If wired LAN is available (YES in S 34 ), the network interface determining unit 1 determines whether or not device error occurs in wired LAN by checking the error status acquisition unit 6 (S 42 ). If device error does not occur in wired LAN (YES in S 42 ), the network interface determining unit 1 determines whether or not the power status is one in which wired LAN can be enabled by checking the power status acquisition unit 5 (S 32 ). The following steps are the same as described above.
If wired LAN is not available (NO in S 34 ) or device error occurs in wired LAN (NO in S 42 ), the network interface determining unit 1 determines whether or not device error occurs in wireless LAN by checking the error status acquisition unit 6 (S 43 ). If device error occurs in wireless LAN (NO in S 43 ), the process returns to the beginning.
If device error does not occur in wireless LAN (YES in S 43 ), the network interface determining unit 1 determines whether or not the power status is one in which wireless LAN can be enabled with reference to the power status acquisition unit 5 (S 35 ). If the power status is one in which wireless LAN can be enabled (YES in S 35 ), the network interface control unit 2 enables wireless LAN (S 36 ). Otherwise (NO in S 35 ), the process returns to the beginning.
If the network setting is set to wireless LAN (S 29 ), the network interface determining unit 1 determines whether or not device error occurs in wired LAN by checking the error status acquisition unit 6 (S 43 ). The following steps are the same as described above. If the network setting is set to disable (S 30 ), the process returns to the beginning.
In the embodiment described above, switching process of network interface is not executed needlessly since situation in which network interface cannot be switched due to the error status of the apparatus after trying to switch network interface when the status of wired LAN communication availability is changed does not occur, and that improves efficiency.
Also, switching process to wired LAN or wireless LAN is not executed needlessly since situation in which network interface cannot be switched due to the error status or the apparatus after trying to switch from wireless LAN to wired LAN or from wired LAN to wireless LAN does not occur, and that improves efficiency.
FIG. 9 is a flowchart illustrating determining whether or not network interface is switched after waiting for a predefined period of time in case of detecting change in the status of wired LAN communication availability. The same steps as in FIG. 8 are given the same reference numerals and descriptions thereof are omitted.
If the status of wired LAN communication availability is changed after network switching event occurs (S 21 ), the wired LAN communication availability acquisition unit 3 detects that the status of wired LAN communication availability is changed (S 22 ) and the time measuring unit 7 measures the passage of a predefined period of time. After the time measuring unit 7 waits for a predefined period of time (S 51 ), the network interface determining unit 1 starts determining which network interface gets enabled (S 25 ). The following steps are the same as described above.
For example, if speed setting of wired LAN is changed, negotiation process on the data link layer level is executed temporarily and it is impossible to communicate by using wired LAN during that time. In this situation, the status of wired LAN availability makes the transition from available, not available, to available.
In the embodiment described above, switching process to wired LAN or wireless LAN is not executed needlessly since it is not necessary to switch network interface each time the status changes in case the status of wired LAN communication availability changes continuously during predefined period of time, and that improves efficiency of the communications apparatus.
Numerous additional modifications and variations are possible in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the disclosure of this patent specification may be practiced otherwise than as specifically described herein.
As can be appreciated by those skilled in the computer arts, this invention may be implemented as convenient using a conventional general-purpose digital computer programmed according to the teachings of the present specification. Appropriate software coding can readily be prepared by skilled programmers based on the teachings of the present disclosure, as will be apparent to those skilled in the software arts. The present invention may also be implemented by the preparation of application-specific integrated circuits or by interconnecting an appropriate network of conventional component circuits, as will be readily apparent to those skilled in the electrical engineering arts. | The present invention provides a novel communications apparatus that includes a plurality of wired LAN functions and wireless LAN functions and facilitates determining which network interface is to be enabled more flexibly. The communications apparatus of this invention switches a plurality of wired LAN functions and wireless LAN functions and includes a network interface control unit that enables and disables wired LAN and wireless LAN, a wired LAN communication availability status acquisition unit that detects that there is a change in the status of communication availability of wired LAN and acquires the status of communication availability of wired LAN, and a network interface determining unit that enables only one network interface from communication availability status of wired LAN acquired by the wired LAN communication availability status acquisition unit and a plurality of operating states of the apparatus. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to offshore facilities used in connection with the exploration and production of oil and gas, and in a particular though non-limiting embodiment, to a docking and drilling vessel system suitable for deploying self-standing risers and conducting oil and gas drilling, production and storage operations.
BACKGROUND OF THE INVENTION
[0002] Offshore drilling is quickly becoming the prevalent method of exploring and producing oil and gas, especially in Western countries where land operations are frequently inhibited by environmental concerns. There is, however, a serious shortfall of offshore drilling units called Mobile Offshore Drilling Units, or MODUs. The relative unavailability of MODUs has resulted in significant delays in many drilling projects. Consequently, the cost of obtaining either a new or existing MODU for an exploration and production operation has dramatically increased over the past decade.
[0003] As will be readily appreciated by those of skill in the art, MODUs are utilized during the early testing phase required to evaluate oil, gas, and other hydrocarbon discoveries. However, due to the lack of floating production facilities and the high cost of MODUs, early testing is seldom accomplished, which often results in unnecessary delays and inaccurate predictions of economic assessments, project development schedules, etc. Moreover, procurement of offshore production and storage facilities required to operate offshore projects in a timely manner can be quite difficult. In extreme circumstances or in especially remote regions, the lag time between hydrocarbon discovery and the production phase can reach 10 years or more.
[0004] Meanwhile, self-standing riser assemblies supported by buoy devices are becoming a more common method of performing oil and gas exploration and production related activities. Compared to the large scale riser assemblies typically serviced by MODUs, the self-standing riser provides for lighter and less expensive riser tubulars (e.g., drilling pipe, stack casing, etc.). Self-standing risers also admit to the use of lighter blowout preventers, such as those used by land drilling rigs.
[0005] Moreover, the top buoy of a self-standing riser system can be positioned near the surface of the water in which it is disposed (for example, less than around 100 ft. below surface level), allowing for efficient drilling in even shallow waters. Furthermore, where riser systems are tensioned and controlled with associated buoyancy chambers, buoy-based systems can be used successfully in much deeper waters.
[0006] However, as those of skill in the art have learned in the field, buoy-based systems utilizing general purpose vessels for riser and buoyancy chamber deployment are deficient in that large-scale operations (e.g., deployment in very deep or turbulent waters, or projects involving multiple combinations of riser strings and buoyancy chambers, etc.) are very difficult to control, and thus installation, operation and maintenance of the resulting system is significantly impaired.
[0007] There is, therefore, a need for a custom vessel that admits to efficient deployment of large-scale riser systems in a manner similar to the manner of a MODU even when a MODU is not available.
SUMMARY OF THE INVENTION
[0008] A sea vessel exploration and production system is provided, wherein the system includes a drilling station formed from at least one section of a first sea vessel hull; and a docking station, which is also formed from at least one section of a second sea vessel hull. A mooring system suitable for connecting the drilling station to the docking station is also provided. Means for anchoring the vessels to the seafloor, and for attaching them to turret buoys, are also considered. Various exploration and production packages, as well as equipment required to deploy and control a self-standing riser system in either deep or shallow waters, are also described.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1A is an overhead view of a docking and drilling station moored end-to-end, according to example embodiments.
[0010] FIG. 1B is a side view of a docking and drilling station moored end-to-end, according to example embodiments.
[0011] FIG. 2 is a schematic diagram of an anchored drilling station and docking station operating a self-standing riser assembly, according to example embodiments.
[0012] FIG. 3 illustrates a sequence of steps for mooring a docking station and a drilling station using an end-to-end method, according to example embodiments.
[0013] FIG. 4 illustrates a sequence of steps for mooring a docking station and a drilling station using a side-by-side method, according to example embodiments.
[0014] FIG. 5 illustrates a sequence of steps for mooring a docking station and a drilling station to a turret buoy anchoring assembly, according to example embodiments.
[0015] FIG. 6 is a schematic diagram of an alternative docking station with side-by-side docking to a docking station, according to example embodiments.
[0016] FIG. 7 is a schematic diagram of alternative docking station mooring schemes for varying current conditions, according to example embodiments.
[0017] FIG. 8 is a schematic diagram of a docking station or a drilling station attached to a turret buoy, according to example embodiments.
DETAILED DESCRIPTION
[0018] The description that follows includes exemplary systems, methods, and techniques that embody various aspects of the presently inventive subject matter. However, it will be readily understood by those of skill in the art that the disclosed embodiments may be practiced without one or more of these specific details. In other instances, well-known manufacturing equipment, protocols, structures and techniques have not been shown in detail in order to avoid obfuscation in the description.
[0019] Referring now to the example embodiment illustrated in FIG. 1A , an overhead view of a docking station 6 and a drilling station 8 are depicted as being moored together in an end-to-end manner. The embodiment of the drilling station 8 shown in FIG. 1B comprises crew quarters and an operations office; a drilling rig; a void space designed for housing and deploying various buoyancy devices 14 ; a helipad; a moon pool 12 ; a plurality of anchor lines used to anchor the system to an associated seabed; and mooring lines configured to moor said drilling station 8 and said docking station 6 together. The example embodiment of the docking station 6 further comprises modular production, testing and injection facilities 10 ; a plurality of anchor lines; and mooring lines configured to mate with the mooring assembly of the drilling station. A self-standing riser disposed in mechanical communication with one or more buoyancy devices 14 is also provided.
[0020] In the embodiment depicted in FIG. 1A , the docking station 6 and drilling station 8 are moored together using mooring lines in such a manner that both portions of the combined vessel are able to properly perform offshore drilling operations. In alternative embodiments, various other devices can be used to secure the mooring system, for example, clamps, rods, latches, locks and other mechanical devices; strong magnets and electrical control systems; vacuum systems, etc.
[0021] Although not illustrated in FIG. 1 , typical embodiments of the docking and drilling stations further comprise a plurality of oil and gas related drilling, production and exploration equipment. For example, a modified land or platform drilling rig installed on the drilling station can be used to operate a self standing riser while maintaining functional stability and efficient operational continuity. Similar equipment disposed within or upon the drilling station 8 enables storage, deployment, lifting, and retrieval operations, as well as storage of additional risers, such as stress joints 16 , and one more buoyancy devices 14 should they be required during drilling operations.
[0022] In further embodiments, hydrocarbons such as oil, gas, liquid natural gas, etc., encountered during the drilling process are separated, treated and stored either onboard or within docking station 6 . In still further embodiments, docking station 6 further comprises modular production facilities 10 and storage space that can be used for testing operations or as a facility to separate oil, gas, water, etc. Other embodiments of the docking station 6 comprise one or more of a flare boom used to bleed off gas and fluid pressure; oil, water and gas separators; and storage facilities used to store crude and previously treated oil and gas. In further embodiments still, water and gas injection equipment used to re-inject wells and the mechanical equipment required to facilitate such operations are also included.
[0023] Since the drilling station does not necessarily have to support deployment of conventional riser and buoyancy chamber systems, it can utilize a typical land or platform drilling rig modified to endure extreme sea and weather conditions. The embodiment depicted in FIG. 2 , for example, illustrates an anchored drilling station and docking station operating in tandem to support and control a self-standing riser system equipped with an associated buoyancy device 14 . The drilling station of FIG. 2 further comprises a void space suitable for the storage and handling of buoyancy devices 14 , as well as a hoisting system and retractable guide rails that assist in guiding the buoyancy devices 14 below the hull of drilling station.
[0024] In various other embodiments, the drilling station depicted in FIG. 2 allows the drilling rig to hoist, lower and otherwise handle self standing riser, casing, drilling pipe, etc., passed through the moon pool 12 . One specific example embodiment permits self standing riser tubulars to be lowered into the water until a desired length is obtained and the required quantity of buoyancy devices 12 are in place. Although not depicted, those of skill in the art will appreciate that further embodiments of the drilling station are equipped to deploy, store and handle most other types of routine or custom fit offshore drilling equipment, such as shear rams, ball valves, blowout preventers and hoists therefor.
[0025] Following installation of the self standing riser, the drilling station can commence drilling, completion, testing and workover operations, etc. As operations continue, some portions of the system can be removed so that the drilling station can be utilized in other types of operations. In further embodiments, the drilling station is utilized to drill a hole in a seabed so as to permit installation of a wellhead and associated casing. In still further embodiments, the drilling station is used to remove and store the riser assemblies, such as stress joints 16 , as well as attendant buoyancy devices 14 and other offshore drilling equipment.
[0026] In some example embodiments, the described installation and removal process is applied to wellheads created by others and abandoned. Such projects would typically utilize cranes, hoists, winches, etc., operating in mechanical communication with the drilling station in order to perform installation and removal of existing riser assemblies, wellheads, production trees and blowout preventers.
[0027] In some embodiments, the void space formed to store and handle buoyancy devices 14 further comprises a moveable floor, tracks, a gantry, etc., that transports buoyancy devices to a desired location (e.g., near the moon pool) to be joined with a self standing riser assembly stack. Various embodiments of the moon pool 12 further comprise retractable guide rails that assist in guiding and delivering the buoyancy devices 14 down below the hull to a deployment station.
End-to-End and Side-to-Side Mooring of the Docking and Drilling Stations
[0028] FIGS. 3 and 4 depict an embodiment of the docking station 6 and the drilling station 8 moored together using end-to-end and side-to-side mooring methods, respectively. In the example embodiment illustrated in Step 1 of both FIGS. 3 and 4 , docking station is towed by a towing vessel toward anchor lines preinstalled by workboats, anchor handling vessels, etc. Towing of the docking and drilling stations can of course be facilitated by any vessel capable of towing another vessel of appropriate size, such as a work boat, a tug, etc.
[0029] Step 2 depicts various transportation vessels (e.g., workboats, towing vessels, etc.) transporting a plurality of anchor lines to fastening members disposed in communication with the docking station 6 . Some embodiments of the fastening members assist in adding tension to the anchor lines, and slowly moving the docking station toward desired site coordinates.
[0030] In the end-to-end embodiment shown in FIG. 3 , the anchor lines are affixed to fastening members positioned on all sides of the docking station 6 . Note, however, that the anchor lines would typically be affixed to fastening members on a particular side of the docking station 6 in the side-to-side method depicted in Step 2 of FIG. 4 . Such embodiments of side-to-side mooring help maintain proper lateral spacing and controlled efficient movement as the drilling station 8 and docking station 6 are joined. In further embodiments, the drilling station 8 is transported to within a close proximity of the docking station 6 during Step 2 , and a plurality of anchor lines are thereafter affixed to fastening members of the drilling station in order to secure the system in a desired dynamic equilibrium.
[0031] Step 3 illustrates the drilling station as disposed in stable operative communication with the docking station 6 . Various known attachment means, such as mooring lines, as well as any new or custom designed fasteners or the like can be used to facilitate stable and reliable operations. In the embodiment depicted in FIG. 3 , the drilling station 8 and the docking station 6 are mutually joined and operated in a back-to-back or end-to-end manner, whereas in the embodiment illustrated in FIG. 4 , the drilling station 8 and the docking station 6 are joined in a side-to-side manner. Either manner will, if configured correctly, permit the drilling station 8 to drill, deploy casing, deploy self standing riser tubulars, etc. In some embodiments, the drilling station 8 is configured to position itself over an existing self standing riser system in order to perform workover operations, well completions, and other common drilling operations.
[0032] In the embodiment illustrated in Step 4 of FIGS. 3 and 4 , the drilling station 8 is disconnected from the docking station 6 and towed away. In a typical example embodiment, anchoring lines previously used to anchor the drilling station 8 in place are attached to the remaining docking station 6 , thereby resulting in a spread mooring configuration suitable for receiving a new vessel. In some embodiments, the docking station is then used as a testing or production vessel to process and separate oil, gas and water, etc. In further embodiments, the docking station provide facilities to inject water and gas back into well(s), power to operate electric submersible pumps, or lifting support to aid with other production methods.
[0033] Step 5 depicts an embodiment of the mooring sequence in which an oil tanker is joined in communication with the docking station 6 . As previously discussed, example embodiments may comprise a wide variety of attachment methods and means, such as mooring, docking, fastening, etc. In one example embodiment, the docking station 6 then utilizes pipes, tubulars, hoses, etc., to transfer oil, gas or other stored fluids to and from the tanker.
End-to-End Mooring Using a Turret Buoy
[0034] FIG. 5 depicts an embodiment of a turret mooring buoy 18 that allows the drilling station and the docking station to cooperate in a synchronized manner even in very poor weather conditions, such as strong winds, rough currents, etc. In the embodiment illustrated in Step 1 of FIG. 5 , conventional mooring lines and anchors are affixed to a turret mooring buoy 18 as known in the art. Embodiments of the drilling station 8 are subsequently towed to the turret mooring buoy 18 , as illustrated in Step 2 . In the embodiment depicted in Step 3 , a plurality of towing vessels position the drilling station in relatively close proximity to the turret mooring buoy 18 , where the drilling station 8 and the turret mooring buoy 18 are mutually joined. In Steps 4 and 5 , the docking station is similarly joined to the system in accord with the principles previously discussed above. In one specific embodiment, the drilling station is also capable of performing a multitude of other offshore drilling functions, including deployment and operation of drilling equipment; the drilling of holes on the seabed and installation of casing; deployment and operation of self-standing riser, etc.
[0035] In the embodiments illustrated in Step 5 and Step 6 , the docking station 6 is moved to a location and attached in communication with turret mooring buoy 18 after completion of operations by the drilling station 8 . In further embodiments, the drilling station is then removed from turret mooring buoy 18 to allow for attachment of the docking station 6 so that testing and production can commence.
Side-by-Side Mooring Using a Spread Mooring System
[0036] Referring now to the example embodiment depicted in FIG. 6 , the docking station 6 and drilling station 8 are joined using a side-by-side mooring system. Various embodiments of the drilling station 8 are affixed to the docking station using a system of attachment mechanisms, such as mooring, docking, fastening devices, etc., which lend support and provide rigid separation in the lateral direction while still allowing mutual vertical movement. In one embodiment, conventional mooring with anchor lines can secure the drilling station 8 and docking station 6 in proximity of a self-standing riser.
[0037] Several embodiments of side-by-side mooring utilize hydraulically compensated cylinders to maintain constant lateral distance and compensate for wave and swell actions. For example, embodiments using a hydraulically compensated cylinder can maintain separation forces while dampening related transient forces caused by wave and swell movement.
End-to-End and Side-by-Side Mooring of the Drilling Station and Docking Station Using the Turret Moored Buoy
[0038] Referring now to the example embodiment in FIG. 7 , side-by-side and end-to-end mooring configurations of the drilling station 8 and docking station 6 attached in communication with a turret mooring buoy 18 is illustrated. In some embodiments, the turret buoy is utilized for situations where a particular area of the water has significantly varying or conflicting currents. In further embodiments, turret mooring buoy 18 is designed to be attached to a self-standing riser, while relative positioning of the drilling station 8 and docking station 6 is maintained. According to still further embodiments, the design of the turret mooring buoy 18 varies depending on the dimensions of the docking or drilling stations, or in conformity with the dimensions of the moon pool 12 .
[0039] In some embodiments, the drilling station 8 and the docking station 8 attach to the turret mooring buoy 18 using mechanical or hydraulic couplers or other fastening devices known in the art. In the embodiment illustrated in FIG. 8 , the turret mooring buoy 18 allows for a 360 degree rotation of the particular station with which it is disposed. For example, the docking station 6 can rotate 360 degrees once it is attached to the turret mooring buoy 18 .
[0040] In some example embodiments utilizing a turret mooring buoy 18 , the drilling station 8 is moored first, and used to perform one or more of drilling, deployment, workover, completion, testing, etc., operations. In other embodiments, the docking station 6 is moored to the drilling station 6 , and used to conduct one or more of the aforementioned operations, as depicted in FIG. 8 . Once the work of drilling station is concluded, it is detached from the turret buoy while the docking station 8 remains behind for continued operations.
[0041] The foregoing specification is provided for illustrative purposes only, and is not intended to describe all possible aspects of the present invention. Moreover, while the invention has been shown and described in detail with respect to several exemplary embodiments, those of ordinary skill in the art will appreciate that minor changes to the description, and various other modifications, omissions and additions may also be made without departing from the spirit or scope thereof. | A sea vessel exploration and production system is provided, wherein the system includes a drilling station formed from at least one section of a first sea vessel hull; and a docking station, which is also formed from at least one section of a second sea vessel hull. A mooring system suitable for connecting the drilling station to the docking station is also provided. Means for anchoring the vessels to the seafloor, and for attaching them to turret buoys, are also considered. Various exploration and production packages, as well as equipment required to deploy and control a self-standing riser system in either deep or shallow waters, are also described. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of U.S. patent application Ser. No. 10/337,712, filed on Jan. 7, 2003 now U.S. Pat. No. 7,142,097, the disclosure of which is incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to vehicle security systems, and more particularly to audio indications issued by a vehicle security system.
2. Discussion of Related Art
Vehicle security systems use a siren or horn to provide feedback to a user. Typically, the siren or horn of a vehicle security system emits a short “chirp” to indicate that it has received a signal from a remote control and is armed, disarmed, etc.
The vehicle security system comprises a security module 101 comprising a siren output 102 . The siren output 102 has two states, on and off. The siren output 102 is received by a tone generator 103 within a siren module 104 . The tone generator is coupled to a speaker 105 for emitting the chirp. Because the siren output 102 is limited to on and off, the aural capabilities of the vehicle security system are limited.
Therefore, a need exists for a modulated siren output.
SUMMARY OF THE INVENTION
According to an embodiment of the present invention, a vehicle security system comprises a security module adapted to detect an event, a memory for storing a composition, and a processor coupled to the security module, wherein upon detecting the event the processor selects the composition from the memory and triggers a modulated signal representing the composition, wherein the modulated signal is received by a speaker.
The vehicle security system further comprising an amplifier coupled between the processor and the speaker.
The vehicle security system comprises an interface coupled to the memory for receiving a composition from a device and storing the composition in the memory. The vehicle security system further comprises a cradle for supporting a sound module comprising the memory, the processor, and the interface, wherein the sound module is adapted to connect to and discount from the cradle.
The memory stores the composition and a table of contents.
The processor decodes the composition.
According to an embodiment of the present invention, a method of generating an aural vehicle security system indication comprises receiving a request from a security module, determining, in a table of contents, a composition corresponding to the request, and generating an aural sound corresponding to the composition.
The table of contents comprises a list of compositions and a list of events.
The method further comprises decoding the composition prior to generating the aural sound.
According to an embodiment of the present invention, a vehicle security system comprises a security module adapted to detect an event and generate a request, an interface coupled to the security module, and a sound module coupled to the interface, wherein the sound module is removable from the interface.
The interface is coupled to a speaker.
The sound module comprises a memory for storing a composition.
The sound module comprises a processor for receiving the request and selecting a composition from a memory corresponding to the request.
The vehicle security system further comprises an amplifier coupled between the processor and a speaker.
The vehicle security system comprises an external interface coupled to a memory for receiving a composition from a device and storing the composition in the memory.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the presents invention will be described below in more detail, with reference to the accompanying drawings:
FIG. 1 is a diagram of a vehicle security system;
FIG. 2 is a diagram of a system according to an embodiment of the present invention;
FIG. 3A is a diagram of a vehicle security system according to an embodiment of the present invention;
FIG. 3B is a flow chart of a method according to an embodiment of the present invention;
FIG. 4 is a diagram of a vehicle security system according to an embodiment of the present invention;
FIG. 5 is an diagram of a system according to an embodiment of the present invention; and
FIG. 6 is a flow chart of a method according to an embodiment of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
According to an embodiment of the present invention a vehicle security system comprises a memory storing, a user selected aural composition. The different compositions can be uploaded to the memory. Different compositions can be played over a sound system corresponding to different security system events. The compositions can be implemented as a personalization of the vehicle security system and/or as a security feature.
It is to be understood that the present invention may be implemented in various forms of hardware, software, firmware, special purpose processors, or a combination thereof. In one embodiment, the present invention may be implemented in software as an application program tangibly embodied on a program storage device. The application program may be uploaded to, and executed by, a machine comprising any suitable architecture.
Referring to FIG. 2 , according to an embodiment of the present invention, a computer system 201 for implementing the present invention can comprise, inter alia, a central processing unit (CPU) 202 , a memory ( 203 ) and an input/output (I/O) interface 204 . The computer system 101 is generally coupled through the I/O interface 204 to a display 205 and various input devices 206 such as a mouse and keyboard. The support circuits can include circuits such as cache, power supplies, clock circuits, and a communications bus. The memory 203 can include random access memory (RAM) read only memory (ROM), disk drive, tape drive, etc., or a combination thereof. The present invention can be implemented as a routine 207 that is stored in memory 203 and executed by the CPU 202 to process the signal from the signal source 208 . As such, the computer system 201 is a general-purpose computer system that becomes a specific purpose computer system when executing the routine 207 of the present invention.
The computer platform 201 also includes an operating system and micro instruction code. The various processes and functions described herein may either be part of the micro instruction code or part of the application program (or a combination thereof) which is executed via the operating system. In addition, various other peripheral devices may be connected to the computer platform such as an additional data storage device.
It is to be further understood that, because some of the constituent system components and method steps depicted in the accompanying figures may be implemented in software, the actual connections between the system components (or the process steps) may differ depending upon the manner in which the present invention is programmed. Given the teachings of the present invention provided herein, one of ordinary skill in the related art will be able to contemplate these and similar implementations or configurations of the present invention.
According to an embodiment of the present invention, an existing vehicle security system (e.g., a security module 101 ) can be augmented with a speaker 301 and onboard transistor driver 302 for driving the speaker, as shown in FIG. 3A . A square-wave based sound can be generated. One or more sound files can be resident in the security system's microcontroller 303 . The microcontroller can be preloaded with one or more compositions that can be selected by a user. A user interface allows the selection of a song for each type of security system event. An amplifier 304 can be added between the security module 101 and the speaker 301 to increase a volume level.
Referring to the user interface and FIG. 3B , preferably, a user issues a command using a remote control unit 305 , wherein the security system comprises a receiver. The security system plays a composition corresponding to the command, for example, a security system arm command is accompanied by composition 1 . The user can select a button or combination of buttons from the remote control unit to put the security system in a programming mode 306 . While in the programming mode a user can scroll through each of the preloaded compositions using a subsequent button selection, playing a next composition in the preloaded set of compositions for each selection of the button or combination of buttons 307 . A subsequent selection of a button or combination of buttons, for example, holding a predetermined button for five (5) seconds, locks the last composition played as corresponding to the command 308 . One of ordinary skill in the art would appreciate that other means exist for controlling a vehicle security system, such as a valet switch mounted in a vehicle or the remote control unit and the valet switch in combination, and that these means can be used for controlling the selection of compositions.
Referring to FIG. 4 , according to an embodiment of the present invention, a siren can be replaced with a speaker 401 and a sound module 402 can be placed between the security module 101 and the speaker 401 . The security system 101 can generate a sound request on a data line 403 . The sound module 402 receives the request and plays an appropriate composition from a memory 404 . The composition can be amplified by an amplifier 408 and played through the speaker 401 .
The sound module 402 is mounted in a cradle 405 . The cradle 405 is a chassis for supporting the sound module 402 such that the sound module can be installed and removed from a vehicle. The cradle 405 is an interface coupling the system module 101 to the sound module 402 . The cradle 405 comprises a wiring harness for connecting the data line 403 to the processor, for supplying power to the sound module 402 and for coupling the sound module 402 to the speaker 401 .
The sound module 402 can be coupled to an external processor such as a personal computer or an MP3 player. The external processor interfaces with the sound module 402 through the interface 406 , such as a serial port, Universal Serial Bus (USB) interface or IEEE 1394, High Performance Serial Bus. The interface 406 enables the storage of compositions (e.g., MP3 files) in the memory 404 . Preferably the memory is one of electrically erasable programmable read-only memory (EEPROM) or flash memory. A processor 407 can be provided to decode compositions of various formats, e.g., MP3, Ogg Vorbis, or WAV files. The amplifier 408 can be provided to control the volume of the sound generated by the speaker 401 .
It should be noted that a composition can be any aural sound, including, but not limited to songs from popular culture, a bird call, the Westminster Chime, etc. Thus, a high quality sound of a user's choosing can be produced.
Variations can exist in how the song is generated, where the song is stored, how songs are selected for each event, if and how new songs can be loaded into the system, how the sound/song is amplified, and what type of speakers are used. Additionally, physical variations may exist that place some or all of the elements into one or more housings. For example, the security module and sound module can be combined into one module.
The user interface comprises a means for setting a current state, such as a button, and a means for indicating the current state of the vehicle security system. For example, an LED light or siren that produces a chirp. The states of the vehicle security system can include armed, disarmed, valet, etc. In addition, the user interface can indicate a composition corresponding to a given vehicle security event. Events can comprise a breach of a vehicle entrance such as a door, a trigger, for example, arming the vehicle security system, or a demo event for playing a selected composition.
The user interface is preferably an application run on a personal computer supporting a graphical user interface (GUI). The user interface allows a user to list files or compositions, upload files to the memory 404 , download stored files, delete files from memory 404 , and upgrade firmware. The files can be copied, reordered, deleted, etc. from the list, for example, by drag and drop). The user interface also displays appropriate security system events, such that compositions can be related to the events.
Referring to FIG. 5 , each event can have one or more corresponding compositions. Events and compositions can be related by flags in a table of contents (TOC) for a list of files, wherein a flag indicates a corresponding event. Therefore, given a request 501 from the security system 101 , the processor 407 can determine from a table of contents 502 and appropriate composition 503 from a playlist 504 . The composition 503 is retrieved from memory based on a user-defined flag relating to the given request and decoded by the processor 407 .
According to another embodiment of the present invention, the order of compositions in a playlist defines which composition corresponds to which event. For example, a first composition in a playlist of three compositions corresponds to an arm event, a second composition corresponds to a disarm event, and a third composition corresponds to a panic event. Thus, a simplified user interface can include only those commands needed for ordering a playlist of compositions, for example, a copy command.
Referring to FIG. 6 , a method for generating, an aural vehicle security system indication comprises receiving a sound request from a security module 601 , wherein the request comprises an event identifier. A composition corresponding to the event identifier is determined from a table containing a plurality of compositions 602 . A sound corresponding to the composition is generated 603 .
Having described embodiments for audio indications issued by a vehicle security system, it is noted that modifications and variations can be made by persons skilled in the art in light of the above teachings. It is therefore to be understood that changes may be made in the particular embodiments of the invention disclosed which are within the scope and spirit of the invention as defined by the appended claims. Having thus described the invention with the details and particularity required by the patent laws, what is claimed and desired protected by Letters Patent is set forth in the appended claims. | A vehicle security system comprises a security module adapted to detect an event, a memory for storing a composition, and a processor coupled to the security module, wherein upon detecting the event the processor selects the composition from the memory and triggers a modulated signal representing the composition, wherein the modulated signal is received by a speaker. | 1 |
FIELD OF THE INVENTION
[0001] This invention relates to the use of milk which is free of the β-casein A 1 protein in the prevention or treatment of coronary heart disease. The invention also relates to the testing of DNA from cells obtained from lactating bovines for the presence of DNA encoding certain β-casein proteins, selecting the bovines on the basis of the testing, and then milking those bovines to produce milk free of β-casein A 1 for use in the prevention or treatment of coronary heart disease.
BACKGROUND OF THE INVENTION
[0002] Coronary heart disease is a major cause of death, particularly in countries where the populations are well-nourished, such as in the western world. Many factors are implicated as risk factors for this disease including obesity, smoking, genetic predisposition, diet, hypertension, and cholesterol.
[0003] Dairy products, especially milk, are a major contributor to the dietary intake of humans, again particularly in western world populations. Milk contains numerous components of nutritional and health benefit. Calcium is one example. However, milk is also a significant source of dietary fat. It is widely accepted that saturated fats found in milk are a risk factor for coronary heart disease. However, the inventor has discovered an additional risk factor present in some bovine milk unrelated to the fat content. What is entirely surprising is the source of the risk. The source is not dependent on the fat content of milk. Instead, it is a milk protein, β-casein, which is linked to coronary heart disease.
[0004] A number of variants of milk proteins have been identified. Initially, three variants of β-casein were discovered (Aschaffenburg, 1961) and were denoted A, B and C. It was later found that the A variant could be resolved into A 1 , A 2 and A 3 by gel electrophoresis (Peterson et. al. 1966). The β-casein variants now known are A 1 , A 2 , A 3 , B, C, D, E and F, with A 1 and A 2 being present in milk in the highest proportions. It is anticipated that other variants may be identified in the future.
[0005] The inventor has determined that it is the milk protein β-casein A 1 which represents the risk factor in bovine milk that is linked to coronary heart disease, or at least is the principal risk factor. This determination on the part of the inventor forms the basis of the present invention.
[0006] There is no relationship between the fat content of milk and β-casein genotype in cows. Therefore, selecting cattle on the basis of milk fat content will not identify which bovines produce the novel risk factor, namely the specific β-casein variant, in their milk.
[0007] There is no significant difference in the fat content of milk produced by cows which are homozygous for the β-casein A 1 allele (i.e. A 1 A 1 ) and cows which are homozygous for the β-casein A 2 allele (i.e. A 2 A 2 ). This is apparent from studies reported in the literature.
[0008] Ng-Kwai-Hang has carried out several studies. One study (Ng-Kwai-Hang et. al., 1990) suggested that milk containing β-casein A 1 rather than β-casein A 2 may have a slightly higher fat content. However, these differences were very small. The differences between milk from A 1 homozygous cows and milk from A 2 homozygous cows were 0.05% (for the first lactation period), 0.07% (for the second lactation period), and 0.04% (for the third lactation period).
[0009] In another study, Ng-Kwai-Hang (in an abstract cited by Jakob et. al., 1990) found the opposite effect (i.e. the A 1 A 1 product had a lower fat content than the A 2 A 2 product). Thus, the 1995 Ng-Kwai-Hang abstract directly contradicts the Ng-Kwai-Hang, et. al., 1990 study.
[0010] McLean et. al., 1984 (McLean) also reported that there was no significant difference in the fat content of milk from cows of A 1 A 1 and A 2 A 2 genotypes (mean±standard error: 45.8±2.6 g/l for milk of A 1 A 1 cows and 48.6±1.9 g/l for milk of A 2 A 2 cows).
[0011] Aleandri et. al., 1990 (Aleandri), shows in Table 5 that the least squares estimates of the effects of different genotypes and their standard errors on fat percentage in milk are 0.12±0.09 for A 1 A 1 cows and 0.07±0.09 for A 2 A 2 cows. Taking into account the standard error for the test, Aleandri indicates that the effects of A 1 A 1 and A 2 A 2 genotypes on milk fat content are equivalent.
[0012] Bovenhuis et. al., 1992 (Bovenhuis), highlights that there are statistical problems associated with the way in which the genotype effects on fat percentages in milk are studied and documented. It is stated that the ordinary least squares estimates may be biased. Bovenhuis points out that the analysis of the effect of a particular genotype on various characteristics of milk is complex in nature and may, among other things, be affected by other genes which may be linked to the gene under study. Bovenhuis attempts to take into account the above variables and to overcome statistical problems by using an animal model method.
[0013] Table 3 of Bovenhuis indicates that, for a statistical model in which each milk protein gene is analysed separately and the A 1 A 1 cows designated as being the standard (i.e. given a value of 0% fat attributable to the genotype), the A 2 A 2 genotype was estimated not to contribute (i.e. 0%) to the fat content of the milk of the animals harbouring that genotype when compared to the A 1 A 1 genotype. The standard error of the test is recorded as 0.02%. Where a statistical model was used in which all milk protein genes were analysed simultaneously (Table 4 of Bovenhuis) and the A 1 A 1 genotype was again designated as being the standard (at 0% fat content attributable to the A 1 A 1 genotype), the A 2 A 2 genotype was estimated to contribute to the fat content of the milk at −0.01 % when compared with the A 1 A 1 genotype. In this study a standard error of 0.02 was designated. Taking into account the standard error of the tests these results indicate that the A 2 A 2 genotype contributes to the fat content of milk in an equivalent manner to the genotype A 1 A 1 .
[0014] Gonyon et. al., 1987 reached the same conclusion as Bovenhuis.
[0015] The level of individual components in milk is influenced by both the genotype and the environment. That is, the variation between animals in milk output or milk composition is due to both genotypic and phenotypic factors. For example, Bassette et. al., 1988 (Bassette) indicates that the composition of bovine milk may be influenced by a number of environmental factors and conditions other than genetic factors. Environmental factors may impact on milk production and the constituents contained within the milk (including fat content). For example, changes in milk composition occur due to:
the stage of lactation (e.g., the fat content of colostrum is often higher; the concentration of fat changes over a period of many weeks as the cow goes through lactation); the age of the cow and the number of previous lactations; the nutrition of the cow including the type and composition of feed consumed by the cow; seasonal variations; the environmental temperature at which the cows are held; variations due to the milking procedure (e.g., the fat content of milk tends to increase during the milking process which means that for an incomplete milking the fat content would generally be lower than normal and for a complete milking the fat content will be higher than normal); and milking at different times of the day.
[0023] It is therefore apparent from the studies in this field that a person skilled in the relevant area of technology would not find a link between the fat content of milk and the β-casein genotype of the milk-producing bovines from which that milk is produced.
[0024] Thus, the inventor has for the first time identified the milk protein β-casein A 1 as a risk factor linked to coronary heart disease in its own right. It is therefore an object of this invention to provide a method of using milk substantially free of β-casein A 1 to prevent or treat coronary heart disease or to minimise the risk of developing coronary heart disease, or to at least provide a useful alternative. It is also an object of the invention to provide a method of producing milk substantially free of β-casein A 1 suitable for use in the prevention or treatment of coronary heart disease or the minimisation of the risk of developing coronary heart disease, or to at least provide a useful alternative.
SUMMARY OF THE INVENTION
[0025] In one aspect of the invention there is provided a method of preventing or treating coronary heart disease in a human which includes the step of at least reducing the intake in that human of β-casein A 1 .
[0026] Preferably the reduction is effected by the human ingesting milk obtained from one or more lactating bovines, or a product processed from that milk, where the milk or product ingested is substantially free of β-casein A 1 .
[0027] Preferably the milk is substantially free of β-casein A 1 but contains any one or more of β-caseins A 2 , A 3 , B, C, D and E.
[0028] More preferably the milk is substantially free of β-caseins A 1 , B and C but contains any one or more of β-caseins A 2 , A 3 , D and E. Most preferably the milk is substantially free of β-caseins A 1 , B and C and contains only β-casein A 2 .
[0029] In a second aspect of the invention there is provided a method of producing milk suitable for use in the treatment or prevention of coronary heart disease from one or more lactating bovines which milk is substantially free of β-casein A 1 but which contains any one or more of β-caseins A 2 , A 3 , B, C, D and E, the method including the steps of:
(i) testing DNA or RNA from cells containing DNA or RNA obtained from the one or more lactating bovines for the presence of DNA or RNA encoding β-casein A 1 ; (ii) selecting bovines which do not have any DNA or RNA encoding β-casein A 1 ; and (iii) milking the selected bovines.
[0033] In another aspect of the invention there is provided a method of producing milk suitable for use in the treatment or prevention of coronary heart disease from one or more lactating bovines which milk is substantially free of β-casein A 1 , B and C but which contains any one or more of β-caseins A 2 , A 3 , D and E, the method including the steps of:
(i) testing DNA or RNA from cells containing DNA or RNA obtained from the one or more lactating bovines for the presence of DNA or RNA encoding any one or more of β-caseins A 1 , B and C; (ii) selecting bovines which do not have any DNA or RNA encoding any one or more of β-caseins A 1 , B and C; and (iii) milking the selected bovines.
[0037] In another aspect of the invention there is provided a method of producing milk suitable for use in the treatment or prevention of coronary heart disease from one or more lactating bovines which milk is substantially free of β-casein A 1 but which contains β-casein A 2 , the method including the steps of:
(i) testing DNA or RNA from cells containing DNA or RNA obtained from the one or more lactating bovines for the presence of DNA or RNA encoding β-casein A 2 ; (ii) selecting bovines which are homozygous for DNA or RNA encoding β-casein A 2 ; and (iii) milking the selected bovines.
[0041] In another aspect of the invention there is provided a method of producing milk suitable for use in the treatment or prevention of coronary heart disease from one or more lactating bovines which milk is substantially free of β-casein A 1 but which contains any one or more of β-caseins A 2 , A 3 , D and E, the method including the steps of:
(i) testing DNA or RNA from cells containing DNA or RNA obtained from the one or more lactating bovines for the presence of DNA or RNA encoding any one or more of β-caseins A 2 , A 3 , D and E; (ii) selecting bovines which have DNA or RNA encoding only for any one or more of β-caseins A 2 , A 3 , D and E; and (iii) milking the selected bovines.
[0045] In another aspect of the invention there is a method of producing milk suitable for use in the treatment or prevention of coronary heart disease from one or more lactating bovines which milk is substantially free of β-casein A 1 but which contains β-casein A 2 , the method including the steps of:
(i) testing DNA or RNA from cells containing DNA or RNA obtained from the one or more lactating bovines for the presence of DNA or RNA encoding β-casein A 1 and DNA or RNA encoding β-casein A 2 ; (ii) separating bovines which are homozygous for DNA or RNA encoding β-casein A 2 from bovines which either have DNA or RNA encoding β-casein A 1 or which have DNA or RNA encoding both β-casein A 1 and β-casein A 2 ; and (iii) milking the bovines which are homozygous for DNA or RNA encoding β-casein A 2 .
[0049] In another aspect of the invention there is provided a method of producing milk suitable for use in the treatment or prevention of coronary heart disease from one or more lactating bovines which milk is substantially free of β-caseins A 1 , B and C but which contains any one or more of β-caseins A 2 , A 3 , D and E, the method including the steps of:
(i) testing DNA or RNA from cells containing DNA or RNA obtained from the one or more lactating bovines for the presence of DNA or RNA encoding any one or more of β-caseins A 1 , B and C and DNA or RNA encoding any one or more of β-caseins A 2 , A 3 , D and E. (ii) separating bovines which have any DNA or RNA encoding any one or more of β-caseins A 1 , B and C from bovines which have DNA or RNA encoding only for any one or more of β-caseins A 2 , A 3 , D and E; and (iii) milking the bovines which have DNA or RNA encoding only for any one or more of β-caseins A 2 , A 3 , D and E.
[0053] Preferably the one or more lactating bovines of any aspect of this invention are Bos taurus bovines.
[0054] More preferably the milk produced according to any aspect of this invention is substantially free of β-casein A 1 and the β-casein contained in the milk comprises greater than 95% by weight β-casein A 2 .
[0055] More preferably the milk produced according to any aspect of this invention is substantially free of β-casein A 1 and the β-casein contained in the milk comprises approximately 100% by weight β-casein A 2 .
BRIEF DESCRIPTION OF THE DRAWINGS
[0056] FIG. 1 is a graph showing the regression relationship between the death rate from Ischaemic Heart Disease (all ages per 100,000 of population for the year 1985) and the estimated average daily intake of β-casein A 1 per head of population (based on country by country dietary information and data on the genotype of the dairy cows in their national herds), over a number of countries
[0057] FIG. 2 is a graph showing the regression relationship between the death rate from Ischaemic Heart Disease (per 100,000 males aged 30-69 for the year 1985) and the estimated average daily intake of dairy protein per head of population over a number of countries.
[0058] FIG. 3 is a graph showing the regression relationship between the death rate from Ischaemic Heart Disease (per 100,000 males aged 30-69 for the year 1985) and the estimated average daily intake of saturated fat over a number of countries.
[0059] FIG. 4 is a graph showing the regression relationship between the death rate from Ischaemic Heart Disease (per 100,000 males aged 30-69 for the year 1985) and the estimated average daily intake of red meat over a number of countries.
[0060] FIG. 5 shows the A 1 and A 2 amplicons for the ACRS genotyping method.
[0061] FIG. 6 shows the electrophoresis results for the ACRS genotyping method.
[0062] FIG. 7 shows the gene fragment amplified in the Primer Extension genotyping method.
[0063] FIG. 8 shows mass spectrometry profile results for the Primer Extension genotyping method.
DETAILED DESCRIPTION OF THE INVENTION
[0064] This invention is applicable to milk, and all products processed from that milk, which milk is substantially free of β-casein A 1 .
[0065] As used herein, the term “treatment” in relation to coronary heart disease means at least a reduction in the risk of a coronary heart disease event occurring in a human. The terms “treat” and “treating” have equivalent meanings.
[0066] Coronary heart disease means any disease or disorder relating to the coronary heart system and includes atherosclerosis and ischaemic heart disease.
[0067] The term “ Bos taurus ” refers to any cow whose pedigree from its three prior generations is 50% or more of Bos taurus origin.
[0068] The term “β-casein A 1 allele” is a term used with reference to one of the variant forms of the β-casein gene. Expression of the A 1 allele results in the production of the β-casein A 1 protein. Where reference is made to the presence of the β-casein A 1 allele in an individual or population, it encompasses both homozygous and heterozygous genotypes with respect to that allele. Similarly, where reference is made to the presence of β-casein A 1 , it encompasses phenotypes resulting from either a homozygous or heterozygous state with respect to the β-casein A 1 allele.
[0069] An example of an animal which is heterozygous for β-casein is a β-casein A 1 A 2 bovine. Some animals are homozygous, for example bovines that are A 1 A 1 for β-casein and those that are A 2 A 2 for β-casein. A β-casein A 2 A 2 bovine is capable of producing only the β-casein A 2 protein.
[0070] Genetic variation within a species is due at least in part to differences in the DNA sequence. While there are relatively few such differences in relation to the number of DNA bases or the size of the genome, they can have a major impact as is evident in the genetic heterogeneity of the human and bovine populations. For example, in bovines, a mutation in the DNA sequence coding for the β-casein protein at nucleotide position 200 has resulted in the replacement of a cytidine base with an adenine base. Thus, the triplet codon affected by this change codes for histidine (CAT) rather than for proline (CCT) at amino acid position 67 of the protein. Thus, the histidine at position 67 results in the cow producing β-casein A 1 while the proline results in the cow producing β-casein A 2 (Note: the preceding discussion assumes that the ancestral bovid expressed β-casein A 2 and that there are no other DNA variations at other positions on the DNA sequence).
[0071] The term “substantially” as used in the expression “substantially free of β-casein A 1 ” reflects that it cannot be said with 100% certainty that a sample of milk is absolutely free of β-casein A 1 . On rare occasions, and despite all efforts to ensure that a herd is β-casein A 1 free, an animal capable of producing β-casein A 1 in its milk could present itself in the herd because of a genetic mutation or because of human error. Herds are formed by the genotype testing of animals and then selecting the desired individuals. All such testing is subject to human error. The phrase “substantially free of β-casein A 1 ” is therefore intended to account for this. Without the word “substantially”, the phrase would be unduly limiting.
[0072] The products processed from milk that form part of this invention are derived from a source of bulk milk (i.e. milk from more than one animal) and include, but are not limited to:
(a) bulk milk (b) bulk milk used to make cheese whether or not the milk has been pasteurised, sterilised or otherwise treated to reduce the the population of microbes prior to cheese making, (c) milk powders, (d) milk solids, (e) caseins, caseinates, and casein hydrolysates, (f) pasteurised, sterilised, preserved milks including microfiltered milks, UHT milks, (g) low fat milks, (h) modified or enhanced milks, (i) ice-cream or other frozen dairy based confections, (j) fermented milk products such as yoghurt or quark, (k) cheeses including full fat, partial de-fatted and fat-free processed cheeses, (l) milk whey, (m) food products enriched through the addition of milk products such as soups, (n) milk from which potentially allergenic molecules have been removed, (o) confections such as chocolate, (p) carbonated milk products, including those with added phosphate and/or citrate, (q) infant formulations which may contain full, partially de-fatted or nonfat milk together with a number of additional supplements, (r) liquid or powdered drink mixtures, and (s) buttermilk and buttermilk powder.
[0092] It has been reported that certain human population groups exhibit a relatively low incidence of coronary heart disease and certain other diseases, notwithstanding the fact that they consume considerable quantities of milk and milk proteins. These people include the Tibetans, rural Gambians, and the Masai and Samburu people of Kenya. The inventor has identified the fact that a major difference between these population groups and other similar population groups is that the milk consumed by the above people is derived from Bos indicus bovines (e.g. the Zebu breed) and from the Yak ( Bos grunniens ). Such milk does not contain β-casein A 1 .
[0093] In addition, a comparative study in Denmark of the causes of morbidity in the Greenland Eskimo population and the predominant Danes, shows very large relative differences that are suggestive of differences in life-style risk factors. One notable difference is that the Danes are large consumers of dairy products whereas the Eskimos are not. The differences in morbidity are illustrated in Table 1 below.
TABLE 1 Age-adjusted differences in morbidity from chronic diseases between Greenland Eskimos and Danes Eskimos/Danes Acute myocardial infarction 1/10 Stroke 2/1 Psoriasis 1/20 Diabetes Rare Bronchial asthma 1/25 Malignant disorders 1/1 Thyrotoxicosis rare Multiple sclerosis 0 Polyarthritis chronica Low Acta Med. Scand., 208: 401-406, (1980)
[0094] A further comparison has been carried out using data from the states of the former West Germany. In this case, the coronary heart disease death rates have been found to correlate strongly with the relative regional average consumption of β-casein A 1 (Table 2). In this instance, the composition of the individual state dairy herds remained virtually constant from the 1950's through to the 1980's.
[0095] The data show a remarkable relationship between the relative incidence of Ischaemic Heart Disease and the relative average consumption of β-casein A 1 across the 8 states. This is in marked contrast to the relatively poor relationships between the incidence of Ischaemic Heart Disease and the recognised listed dietary risk factors.
TABLE 2 A comparison of the relative nutritional risk factors for coronary heart disease and the incidence of Ischaemic Heart Disease (IHD) in the states of the former Federal Republic of Germany (Schleswig-Holstein = 1.00) Relative intake of dietary component Relative Saturated β-A 1 incidence Fat Cholesterol Alcohol Carbohydrates Energy casein of IHD Schleswig 1.00 1.00 1.00 1.00 1.00 1.00 1.00 Holstein Niedersachsen 0.97 0.96 1.00 0.98 0.99 0.92 0.88 Nordrhein 0.99 1.02 0.99 1.00 1.02 0.97 1.00 Westfalen Hessen 0.95 0.96 0.98 0.98 0.98 0.75 0.74 Rheinland-Pfalz 0.95 0.99 1.00 1.02 1.0 0.87 0.78 Saarland 0.94 0.93 0.98 1.01 0.98 0.90 0.88 Baden 0.93 1.02 1.02 1.05 1.03 0.50 0.72 Wurttenburg Bayern 0.96 0.99 1.22 1.06 1.02 0.50 0.74
[0096] A regression relationship between Ischaemic Heart Disease and fat intake was conducted and was shown to be not significant (p<0.0684, r 2 =0.20). However, the regression between Ischaemic Heart Disease and the intake of β-casein A 1 was highly significant (p<0.0001, r 2 =0.71). The regression relationships are:
IHD= 1.56(±0.79) Fat Intake+86.7(±74.9)
IHD= 81.7(±13.5) β-Casein A 1 −5.4(±40.4)
[0097] The multiple regression relationship was then generated. In this case, the inclusion of both fat intake and β-casein A 1 intake did not improve the relationship over that with β-casein A 1 alone. The regresion relationship is:
IHD= 78.3(±15.6) β-Casein A 1 +0.259(±0.557) Fat−19.2(±51.0)
[0098] The analyses of the relationships between various dietary factors and Ischaemic Heart Disease outlined in this document indicate the potential importance of the β-casein variant as a risk factor for heart disease. The difference between the two casein variants is only one amino acid. This suggests that the products of proteolysis of these variants may be linked to the identified risk factor. Some indication of the number, and the major product fragments into which they are split by proteolytic action of a variety of enzymes, is illustrated for the β-caseins in Table 3.
TABLE 3 The β-casein family of proteins Former Recommended Nomenclature Nomenclature Source of Fragment β-casein A 1 β-CN A 1 -5P — β-casein A 2 β-CN A 2 -5P — β-casein A 3 β-CN A 3 -5P — β-casein B β-CN B-5P — β-casein C β-CN C-4P — β-casein D β-CN D-4P — β-casein E β-CN E-5P — γ 1 -casein A 1 β-CN A 1 -1P(f29-209) β-CN A 1 -5P γ 1 -casein A 2 β-CN A 2 -1P(f29-209) β-CN A 2 -5P γ 1 -casein A 3 β-CN A 3 -IP(f29-209) β-CN A 3 -5P γ 1 -casein B β-CN B-1P(f29-209) β-CN B-5P γ 2 -casein A 2 β-CN A 2 (f106-209) β-CN A 1 -5P or β-CN A 2 -5P γ 2 -casein A 3 β-CN A 3 (f106-209) β-CN A 3 -5P γ 2 -casein B β-CN B (f106-209) β-CN B-5P γ 3 -casein A β-CN A (f108-209) β-CN A 1 -5P, β-CN A 2 -5P or β-CN A 3 -5P γ 3 -casein B β-CN B (f108-209) β-CN B In addition there are a number of protease peptone components. Eigel, W. N., Nomenclature of Proteins of Cow's Milk: Fifth Revision J. Dairy Sci., 67: 1599-1631, (1984)
[0099] Bovine milk is an important source of proteins and other nutrients required by humans. A high proportion of the common domestic cattle breeds, such as the Holstein, express the β-casein A 1 allele. For example, it is estimated that in the late 1980s more than 70% of the Californian dairy herd carried the A 1 allele. As noted previously, the β-casein A 1 variant is of particular interest and therefore, considering its contribution to milk consumed by the human population in many parts of the world, the proteolysis products of β-casein A 1 are of particular interest.
[0100] In the graph shown in FIG. 1 , the incidence of Ischaemic Heart Disease is plotted against the estimated average consumption of β-casein A 1 (and its derived proteolysis products). FIG. 1 shows a very strong correlation between the consumption of β-casein A 1 and death rate from Ischaemic Heart Disease. In contrast, the correlation with the consumption of dairy protein ( FIG. 2 ) is much lower. Neither saturated fat consumption ( FIG. 3 ) nor the consumption of red meat ( FIG. 4 ) show the strong correlation which the inventor has identified in relation to the consumption of β-casein A 1 , both between countries and within countries.
[0101] The single amino acid difference between the two predominant β-casein variants has highlighted the potential role of a difference in the proteolysis products from different β-casein variants as potential risk factors for coronary heart disease. Therefore, the potential impact of pasteurisation is of interest, as prolonged heating is a factor that is known to influence proteolysis. In particular, this relates to the more severe forms of heat treatment that were used in the early years of pasteurisation (e.g. Holder pasteurisation which heats milk to 63° C. and holds it for 20-30 minutes). Hence the impact of the introduction of Holder pasteurisation on the death rate from coronary heart disease is of interest. The inventor has examined the available data and the results of the analyses are presented in Table 4.
[0102] The analyses reveal a very marked and sudden increase in the death rate from coronary heart disease in the four years after the introduction of Holder pasteurisation. Such data would suggest the presence of a novel risk factor associated with pasteurisation. It is the inventor's contention that this risk factor may be associated with a derivative of beta-casein A 1 (for example, a proteolysis product).
TABLE 4 Comparison of the death rates due to coronary heart disease before and after the introduction of Holder Pasteurisation in different parts of the UK Angina pectoris (AP1) Cerebral embolism Population Holder intro. mort. per mill. and thrombosis (CET) group year AP1 AP2 AP3 Δ% CET1 CEL2 CET3 Δ% U.K. Edinburgy 1923 1925 67 92 37 a 1924 174 236 36 Glasgow 1924 1924 56 91 62 a 1924 77 101 31 Dundee 1924 1925 42 64 52 a 1925 162 188 16 Aberdeen 1926 1926 91 135 48 a 1927 121 227 88 Lanarkshire 1935 1937 188 375 99 b 1938 153 193 26 (excluding 1947 1948 685 1185 73 1948 298 518 74 Glasglow) 1952 1954 1185 1523 29 1954 518 680 31 Country of 1954 1954 963 1710 78 1954 610 823 35 Sutherland Country of 1956 1956 1610 2848 78 1956 955 1398 46 Bute London Admin. 1925 1925 31 112 261 c 1926 90 120 33 County Average increase 82 42 Norway Oslo 1922 1922 3 43 1333.3 d not available Columns AP1 and CET1 denote the year of commencement of the sudden rise in the appropriate mortality. Columns AP2 and CET2 denote the appropriate average mortality for the 4 years immediately preceeding the year of introduction. Columns AP3 and CET3 denote the appropriate average mortality for the 4 years immediately succeeding the introduction of pasteurisation. Δ% represents average increase. a Possibly low because deaths ascribed to “coronary thrombosis” were not included in International List No. 89 in Scotland until 1931. b Possibly high as deaths ascribed to “coronary thrombosis” were included in International List No. 94. c Possibly high because after 1927 all deaths ascribed to “coronary thrombosis” were included (unlike those in Scotland) in International List No. 89. d Mortality ascribed to the following classification groups: angina pectoris, infarctus cordis, sclerosis art. coron. Cordis.
[0103] It is possible, however, that a specific fragment or fragments of β-casein A 1 affect the body's immune system as a result of their immunosuppressant properties. By reducing or substantially eliminating the presence of β-casein A 1 in the diet of an individual, it is believed that its immune response may be enhanced, or immunosuppression reduced, thereby improving the general well-being of the individual. It is believed that some individuals may be particularly susceptible to the presence of β-casein A 1 , and it may be possible to develop a test for such susceptible individuals, and to recommend that they reduce or eliminate the consumption of milk or other dairy products containing β-casein A 1 .
[0104] In humans, low density lipoprotein (LDL) oxidation is considered to be a primary step in the evolution of artherosclerotic damage (Steinberg et. al., 1989). Analysis of protein oxidation products isolated from atherosclerotic lesions implicates the tyrosyl radical (a reactive nitrogen species) and hypochlorous acid in LDL oxidation (Heinecke et. al., 1999). In addition, it has been found (Torreilles and Guerin, 1995) that peptides from bovine casein hydrolysates could promote peroxidase-dependent oxidation of human LDLs. The reaction is independent of free metal ions but requires casein-derived peptides with tyrosyl end residues. This implies that the tyrosyl ending peptide is a diffusable catalyst that conveys oxidising potential from the active site of the heme enzyme to LDL lipids. Casomorphin-7 is a potential source of a tyrosyl radical. It is produced from β-casein A 1 but not β-casein A 2 (Jinsmaa et. al., 1999).
[0105] Recognising that dairy products free from β-casein A 1 are desirable, it is preferable to ensure that the animal from which the product is derived has been tested for the presence of the β-casein A 1 allele. Subsequent separation of the bovines into separate herds and/or selective breeding programmes (selecting for β-casein A 1 negative animals) can be carried out to eliminate the presence of the β-casein A 1 from the herd. It will be recognised that such testing may be carried out in a number of ways without departing from the scope of the present invention.
[0106] Any known method for the genotyping of bovines may be used. Such methods can be specific for DNA or RNA encoding either β-casein A 1 or β-casein A 2 . However, general methods which do not specifically test for DNA or RNA encoding β-casein A 1 , but additionally test for DNA or RNA encoding other β-caseins, may also be used to form a herd of bovines which do not produce β-casein A 1 or produce only β-casein A 2 in their milk.
[0107] For the avoidance of any doubt, any reference to DNA in the methodology of this invention is intended to include cDNA (which is DNA derived from RNA).
[0108] For example, it is known that β-casein A 1 has histidine at position 67 of the protein whereas β-casein A 2 has proline at the same position. This is due to the presence of an adenine nucleotide at position 200 of the β-casein DNA. This produces the triplet codon that specifies histidine (CAT) rather than proline (CCT). A test which identifies the codon that will specify histidine at position 67 of the β-casein protein can therefore be used to exclude bovines which produce β-casein A 1 in their milk.
[0109] Similarly, a test which identifies the codon that will specify proline at position 67 of the β-casein protein can therefore be used to select bovines which produce β-casein A 2 (or β-caseins A 3 , D or E) in their milk. While a test for animals that are homozygous for the presence of CCT (that codes for proline) at codon 67 of an animal's β-casein gene does not unequivically show whether or not the animal is homozygous for the β-casein A 2 allele, the test can show that an animal does not possess any of the alleles for β-casein A 1 , B and C. Such a test does not need to be any more specific because culling animals negative for the test will mean the elimination of β-casein A 1 producing animals from the herd.
[0110] It is also known that β-caseins B and C, in addition to β-casein A 1 , have histidine at position 67. Also, β-caseins A 3 , D and E, in addition to β-casein A 2 , have proline at position 67. Therefore, a test which distinguishes between the codons that specify proline and histidine at position 67 will also distinguish between β-caseins A 1 , B and C on the one hand and β-caseins A 2 , A 3 , D and E on the other hand.
[0111] For example, while a test for the presence of CAT (histidine) or absence of CCT (proline) in one or other or both of an animal's alleles at codon 67 of its β-casein gene does not unequivocally show whether or not the animal contains the β-casein A 1 allele, the test can show that an animal may contain one or more of the alleles for β-casein A 1 , B and C. Such a test does not need to be any more specific because culling animals positive for the test (i.e. absence of the proline codon in at least one allele) will mean the elimination of β-casein A 1 producing animals from the herd.
[0112] A DNA or RNA test which gives positive identification for animals homozygous for CCT (proline) at codon 67 can therefore be used to ascertain whether a particular bovine does not possess a β-casein A 1 allele, whether homozygous or heterozygous. Thus, bovines which do possess the CCT (proline) at codon 67 at one or both alleles can therefore be culled from a herd to give a herd which is free of the β-casein A 1 allele. Milk obtained from that herd therefore cannot contain β-casein A 1 .
[0113] Where it is known that the genetic makeup of the herd is such that the only possible alleles possessed by the individuals are for β-caseins A 1 and A 2 , the culling from the herd of those bovines positive for histidine at position 67 gives a herd where each individual is homozygous for the β-casein A 2 allele. Such a herd will produce milk possessing only β-casein A 2 .
[0114] The determination of whether the genotype at codon 67 of the β-casein gene is CCT (proline) or CAT (histidine) can be made by many different methods that are available and which could be used to assay for this single nucleotide polymorphism (SNP). The methods include DNA sequencing, SSCP (single stranded conformation polymorphism), allele specific amplification, and assays designed using proprietary chemistries such as Taqman™ (PE Biosystems), Invader™ (Third Wave Technologies), SnapShot™ (PE Biosystems), Pyrosequencing™ (Pyrosequencing AB), Sniper™ (Pharmacia), and DNA chips (hybridisation or primer extension chips).
[0115] The preferred method should have the ability to function well with rapidly extracted impure DNA. High test throughput (>1000 of samples per day) at low cost is desirable. Since the preferred objective is to identify bovines that are homozygous for the β-casein A 2 allele, the unequivocal positive identification of animals homozygous for CCT at codon 67 is preferred, rather than simply the absence of a result in a test for the alternative CAT codon.
[0116] Two examples of practical methods for the large scale genotyping of bovines are:
A manual ACRS (amplification created restriction site) method which can be conducted easily in any molecular genetics laboratory and requires no specialist equipment or devices. The method can be easily scaled up to analyse hundreds of samples per day. A highly automated method such as the Sequenom™ primer extension and mass spectrometry system which is capable of analysing thousands of samples per day.
[0119] The aim of the ACRS method is to create an amplicon in which only one allele of an SNP will form a restriction site. The restriction site is created by site directed mutagenesis in the amplification step.
[0120] A Dde1 restriction site can be created when the nucleotides CT are present at nucleotide 200 and 201 (positions 2 and 3 of codon 67) of the β-casein gene. This would positively identify the presence of the CCT (proline) codon.
[0121] In Example 1 below, the 3′ section of the Casein Dde2 primer has a mismatch at its penultimate nucleotide ( FIG. 5 ). This is important as it creates a Dde1 restriction site in the A 2 amplicon only (shown in italics in FIG. 5 ). In FIG. 5 , codon 67 in each template is in bold lowercase. The template is reversed to present the primer in the usual 5′-3′ orientation. The mismatch base is underlined.
[0122] Variations of the test could include modification of the sequence of the 5′ end of the Casein Dde2 primer or 5′ extension of the Casein Dde2 primer with a nucleotide sequence homologous to the β-casein template or 5′ extension of the Casein Dde2 primer with nucleotides which are not homologous to the β-casein sequence. The second primer for the ACRS is less critical and many compatible primers could be used. The primer known as Casein4 5′-CCTTCTTTCCAGGATGAACTCCAGG-3′ (SEQ ID NO: 2) has been found to be the most effective.
[0123] PCR amplification with this pair of primers produces a 121 base pair fragment in all β-casein alleles. However, the definitive diagnostic step is that only alleles with CT at positions 200 and 201 (i.e. specifying amino acid 67 of the β-casein) can be cut with the restriction enzyme Dde1. This produces distinctive 86- and 35-base pair fragments.
[0124] The first step of the primer extension method is PCR amplification of the region of the β-casein gene containing codon 67. In Example 2 below, a 319 bp fragment (shown in FIG. 7 ), was amplified. In FIG. 7 , the primer regions are shown underlined. Alternate bases of the SNP are shown bracketed.
[0125] The post PCR product is cleaned with a SAP reaction to remove unincorporated dNTPs. An extension primer complementary to the bold itallicised sequence is added to the cleaned product along with an extension mixture containing ddA, ddC, ddT and dG. The following size extension products are obtained:
SEQ ID Mass Name Sequence (5′-3′) NO: (Da) Primer AGR-RMA6 GTTTTGTGGGAGGCTGTTA 3 5920.90 Contam- (Pause) GTTTTGTGGGAGGCTGTTAG 4 6250.10 inant Analyte A GTTTTGTGGGAGGCTGTTAT 5 6209.10 Analyte C GTTTTGTGGGAGGCTGTTAGG 6 7205.70 GA
[0126] If codon 67 of β-casein is CAT, a 20 bp, 6209.10 Dalton product is obtained, whereas if the sequence is CCT, a 23 bp, 7205.70 Dalton product is obtained. These products can be clearly distinguished and separated from possible contaminants by MALDI-TOF mass spectrometry.
[0127] The results of the genotype testing obtained from either method are then used to select bovines positively identified as having CCT (proline) at position 67 at both alleles. Such bovines cannot produce β-casein A 1 in their milk. The selected bovines are kept in a separate herd and are milked separately. Ideally the milk from that separate herd is kept separate from other milk which may contain β-casein A 1 .
[0128] The selected bovines may be uniquely identified (e.g. alternatives include ear-tagging with a unique tag, or use of an electronic tag or use of a specific tag that identifies the bovine as being free of the β-casein A 1 allele or branding for future identification). The selected bovines are milked to give milk free of β-casein A 1 . Preferably, the milk is phenotype tested to confirm that the milk is substantially free of β-casein A 1 .
[0129] A bulk quantity of milk from the selected bovines may then be processed into one or more milk products, such as fresh milk, cheeses, yoghurts, milk powders etc.
[0130] Finally, it will be appreciated that various other alterations and modifications may be made to the foregoing without departing from the spirit or scope of this invention.
EXAMPLES
Example 1
ACRS Method
[0131] At least 10 hairs were pulled from the end of the tail switch of a cow so that the hook-shaped follicles were retained on the end of the removed hairs. This was achieved easily by pulling the tail hairs upward while holding the rest of the switch down. If the tail has been docked, longer hairs from the end of the docked tail or other locations on the body may be substituted. Tail hairs are preferred.
[0132] Five hair follicles from one cow were cut into a sterile 1.5 ml microfuge tube. Solution A (200 μl) was added to the tube and the tube placed in a boiling water bath for 1 5 minutes. The tube was removed and Solution B (200 μl) added followed by mixing.
Solution A (200 mM NaOH) Solution B (100 mM Tris-HCl, pH 8.5 with an extra 200 mM HCl)—prepared by combining 1 M Tris-HCl, pH 8.5 (10 ml) with conc. HCl (1.67 ml) and making up to 100 ml with distilled water.
[0135] Crude DNA extract (1.5. μl) from hair follicles (prepared as above) or DNA (20-50 ng) (prepared by another method) was transferred to a well of a 96-well PCR plate. PCR cocktail (20 μl) was added to the well. The well was overlayed with mineral oil and centrifuged briefly to remove air bubbles.
[0136] The PCR cocktail was prepared according to the following:
Components Final Concentration 10× PCR Buffer minus Mg (GibcoBRL ®): 20 mM Tris-HCl (pH 8.4), 50 mM KCl 2 mM dNTPs mixture (GibcoBRL ®): 0.2 mM each 50 mM MgCl 2 (GibcoBRL ®): 1.3 mM Primers: 20 μM Casein4 0.5 μM 20 μM CaseinDde2 0.5 μM Taq DNA Polymerase 5 U/μl (GibcoBRL ®): 0.75 units per reaction
[0137] The primers used are:
Casein4 (SEQ ID NO:2) 5′-CCTTCTTTCCAGGATGAACTCCAGG-3′ CaseinDde2 (SEQ ID NO:1) 5′GAGTAAGAGGAGGGATGTTTTGTGGGAGGCTCT-3′
[0138] PCR was carried out on an MJ Research PTC200 (hot bonnet) using the following protocol:
1 cycle 94.0° C. 4 min 35 cycles 94.0° C. 30 sec Denature 60.0° C. 30 sec Anneal 72.0° C. 30 sec Extend 1 cycle 72.0° C. 4 min end 4.0° C.
[0139] Following PCR, restriction enzyme cocktail (10 μl) was added and the mixture incubated at 37° C. overnight. The restriction enzyme cocktail was prepared according to the following:
Components Final Concentration Dde I 10 U/μl (GibcoBRL ®) 4.5 units per reaction REACT ® 3 (GibcoBRL ®) 25 mM Tris-HCl (pH 8.0), 5.0 mM MgCl 2 , 50 mM NaCl
[0140] The amplification product (10 μl) was analysed by electrophoresis (80V, 1 hour) in ethidium bromide stained agarose gel (3%, 1×TBE).
[0141] FIG. 6 shows the results of 20 samples analysed by the procedure outlined above.
[0142] A size standard ladder was loaded in position 0. The 100 bp band is identified in FIG. 6 . The negative control (no DNA) was loaded in position 20. Samples homozygous for CT at positions 2 and 3 of codon 67 of the β-casein gene result in a single 86 bp band when cut by Dde1. This is shown in load positions 1,2,10,11,12,13,14, and 17. Samples not containing CT at positions 2 and 3 of codon 67 of the β-casein gene are not cut by Dde1, leaving a single 121 bp band. This is shown in load positions 4,5,7 and 9.
[0143] Heterozygous samples result in both cut (86 bp) and uncut (121 bp) bands. This is shown in load positions 3,6,8,15,16,18 and 19. Because of heteroduplex formation, the uncut band (121 bp) is expected to be more intense than the cut band (86 bp).
Example 2
Primer Extension Method
[0144] DNA extracts from hair follicles were prepared using the method described in Example 1. Alternatively, genomic DNA isolated by other methods can be used at a concentration at about 2.5 ng/μl.
[0145] A DNA sample (1 μl) from each of 96 animals was placed into a 96 well PCR microtitre plate (or alternatively, from each of 384 animals into a 384 well PCR plate).
[0146] For the 96 well plate, a cocktail of the following reagents was prepared in a 1.5 ml microtube. The cocktail (4 μl) was added to each well in the plate with a repeating pipette.
Reagent Volume μl Water (HPLC grade) 222 10× Hotstar Taq PCR buffer 50 containing 15 mM MgCl 2 HotStar Taq Polymerase (5 U/μl) 4 25 mM MgCl 2 20 dNTP 25 mM 4 Forward and reverse primer mix 100 Forward: actggattatggactcaaagatttg (SEQ ID NO: 7) Reverse: aaggtgcagattttcaacat (SEQ ID NO: 8) (1 μM each primer)
[0147] PCR was carried out using the following protocol:
1 cycle: 95° C. 15 minutes 45 cycles: 95° C. 20 seconds 56° C. 30 seconds 72° C. 1 minute 1 cycle: 72° C. 3 minutes end 4° C.
[0148] The following SAP solution was prepared in a 1.5 ml microtube:
Reagent Volume μl Nanopure water 792.54 hME Buffer (Sequenom, San Deigo) 88.06 Shrimp alkaline phosphatase 155.4
[0149] The solution was mixed well and centrifuged for ten seconds at 5000 RPM.
[0150] SAP solution (2 μl) was transferred to each well of the plate containing the samples. The plate was incubated using a thermocycler at 37° C. for 20 minutes, 85° C. for 5 minutes, and then holding at 4° C.
[0151] The following extension cocktail was prepared in a 1.5 μl microtube:
Reagent Volume μl Nanopure Water 895.11 μl Sequenom 10× hME extend buffer with 2.25 103.6 μl mM ddA, ddC, ddT, dG Primer (100 uM) 27.97 μl RMA6 R: gttttgtgggaggctgtta (SEQ ID NO: 9) 9.32 μl Thermosequenase (32 U/μl)
[0152] The extension cocktail (2 μl) was added to each well of the sample plate. The plate was sealed and thermocycled as follows:
1 cycle: 94° C. for 2 minutes 40 cycles: 94° C. for 5 seconds 52° C. for 5 seconds 72° C. for 5 seconds End 4° C.
[0153] Prior to mass spectrometry the samples were cleaned using SpectroCLEAN and then analysed using MALDI-TOF MS.
[0154] The profiles obtained for homozygous and heterozygous animals for the CCT and CAT SNPs are shown in FIG. 8 . The location of the primer, analyte A and analyte C extension products are shown.
INDUSTRIAL APPLICATION
[0155] The invention provides a useful food product capable of increasing the health of an individual, or the health of a population. The invention relates to a method of preventing or treating coronary heart disease in a human population which derives some of its food intake from milk or other dairy products by reducing or substantially eliminating the presence of β-casein A 1 within the diet of that population.
REFERENCES
[0000]
1. Aleandri, R., Buttazzoni, L. G., Schneider, J. C., Caroli, A., and Davoli, R. (1990) J. Dairy Sci., 73, 241-255.
2. Aschaffenburg, R. (1961) Nature, 192, 431-432.
3. Bassette, R., and Acosta, J. S. (1988) Fundamentals of Dairy Chemistry, 3 rd Ed.,—Chapter 1: Composition of Milk (Ed. Wong, N. P.) Van Nostrand Reinhold, New York, pp 1-38.
4. Bovenhuis, H., van Arendonk, J. A. M., and Korver, S. (1992) J. Dairy Sci., 75, 2549-2559.
5. Gonyon, D. S., Mather, R. E., Hines, H. C., Haenlein, G. F. W., Arave, C. W., and Gaunt, S. N. (1987) J. Dairy Sci., 70, 2585-2598.
6. Heinecke, J. W. (1999) FASEB J., 13, 1113-1120.
7. Jakob, E. and Puhan, Z. (1997) Bulletin of the IDF, 304, pp 2-3 and 6-8.
8. Jinsmaa, Y. and Yoshikawa, M. (1999) Peptides, 20, 957-962
9. McLean, D. M., Graham, E. R. B., Ponzoni, R. W., and McKenzie, H. A. (1984) J. Dairy Res., 51, 531-546.
10. Ng-Kwai-Hang, K. F., Monardes, H. G., and Hayes, J. E., (1990) J. Dairy Sci., 73, 3414-3420.
11. Peterson, R. F., and Kopfler, F. C. (1966) Biochem. Biophys. Res. Commun., 22, 388-392.
12. Steinberg, D., Parthasarathy, S., Carew, T. E., Khoo, J. C. and Witzum, J. L. (1989) N. Engl. J. Med., 320, 915-924.
13. Torreilles, J. and Guerin, M. C. (1995) French Compt. Rendu Seances Soc. Biol. Filial, 189, 933-945. | A milk which is free of β-casein A 1 protein in the prevention or treatment of coronary heart disease is disclosed. In addition, a process for the testing of DNA from cells obtained from lactating bovines for the presence of DNA encoding certain β-casein proteins, selecting the bovines on the basis of the testing, and then milking those bovines to produce milk free of β-casein A 1 for use in the prevention or treatment of coronary heart disease is disclosed. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a Continuation of U.S. application Ser. No. 09/274,286 filed Mar. 22, 1999 now U.S. Pat. No. 6,273,947.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to methods of preparing a compound semiconductor crystal and to the compound semiconductor crystals prepared thereby, and particularly to methods of preparing a carbon-containing, compound semiconductor crystal and compound semiconductor crystals obtained thereby.
2. Description of the Background Art
It has been conventionally well known that as for an LEC method using a stainless chamber there is a correlation between the CO gas concentration provided in the chamber and the carbon concentration of a GaAs crystal in a high-pressure Ar gas ambient.
FIG. 3 is a graph of carbon concentration in a GaAs crystal versus CO gas concentration in a LEC furnace found in Advanced Electronics Series I 4 Bulk Crystal Growth Technology , Keigo Hoshikawa, BAIFUKAN, p.184, Fig. 7.22. FIG. 3 shows that carbon concentration in a GaAs crystal and CO gas content in the LEC furnace are correlated by a straight line. In the LEC method, the correlation represented in the graph is applied to the adjustment of carbon concentration in a GaAs crystal. The carbon concentration in a GaAs crystal can be controlled by adjusting the CO gas content in the ambient gas using a CO gas cylinder and an Ar gas cylinder for dilution connected to the stainless chamber.
FIG. 4 shows an exemplary GaAs crystal growth equipment for the LEC method disclosed in Japanese Patent Laying-Open No. 1-239089. Referring to FIG. 4, Japanese Patent Laying-Open No. 1-239089 discloses a method of preparing a single crystal of compound semiconductor by placing in a predetermined gas ambient a raw-material housing portion housing a raw-material melt, detecting at least the concentration of one of H 2 , O 2 , CO 2 and CO corresponding to components of the ambient gas, and controlling the detected concentration of a component at a predetermined value to keep over the entirety of an ingot a predetermined concentration of a residual impurity mixed into a resulting single crystal.
This method can, however, not be applied in preparing a compound semiconductor crystal in a gas-impermeable airtight vessel incapable of supplying a gas from outside the airtight vessel, such as a quartz ampoule.
Japanese Patent Laying-Open No. 3-122097 discloses a method of preparing a GaAs crystal in a quartz ampoule wherein a carbon source is arranged internal to the ampoule and external to a crucible in fluid communication with a polycrystalline compound provided as a raw material to allow the GaAs crystal to be doped with carbon. “Fluid communication” means a free flow of vapor and heat between the inside and outside of the crucible which allows carbon to be transferred into the crucible and thus to a melt. In accordance with the method, a carbon disk is arranged on an opening of a cap. It discloses that the ingots of various doped levels can be provided by varying the amount of carbon arranged external to the opening and/or the crucible.
With this method, however, a large amount of carbon source is placed above the melt. Thus fine powder of carbon falls thereon and can thus vary the carbon concentration thereof. Particularly, the controllability can be poor at a slight carbon concentration corresponding to a level of 0.1×10 15 cm −3 to 2×10 15 cm −3 .
Japanese Patent Laying-Open No. 64-79087 discloses a method of preparing a single crystal of GaAs doped with carbon to reduce dislocation, using a reactor or a boat for crystal growth at least partially formed of carbon. It discloses that when a graphite boat is used, a part of the carbon boat changes into a gas (CO or CO 2 ) due to oxygen derived from a small amount of As 2 O 3 , Ga 2 O or the like remaining in the quartz reactor and the gas is thus added to the single crystal of GaAs in synthesis reaction or in single-crystal growth.
In accordance with this method, however, it is difficult to control the carbon concentration in the crystal due to the difficulty of controlling the amount of As 2 O 3 , Ga 2 O or the like remaining in the quartz reactor. In particular, the controllability can be poor at a slight carbon concentration corresponding to a level of 0.1×10 15 cm −3 to 2×10 15 cm −3 .
Japanese Patent Laying-Open No. 2-48496 discloses a method of preparing a Cr-doped, semi-insulating GaAs crystal wherein a quartz boat or a quartz crucible is used to grow the crystal under the existence of nitrogen oxide or carbon oxide. It discloses that when a GaAs crystal is grown under the existence of nitrogen oxide or carbon oxide, the oxide serves as an oxygen doping source to reduce the Si concentration of the grown crystal so that a semi-insulating crystal is reliably provided.
However, this method contemplates control of oxygen concentration and does not describe control of carbon concentration.
SUMMARY OF THE INVENTION
One object of the present invention is to provide a method of preparing a compound semiconductor crystal allowing the compound semiconductor crystal to be doped with carbon in high reproducibility, and a compound semiconductor crystal prepared thereby.
In one aspect of the present invention, a method of preparing a compound semiconductor crystal includes the steps of sealing carbon oxide gas of a predetermined partial pressure and a compound semiconductor provided as a raw material in a gas-impermeable airtight vessel, increasing the temperature of the airtight vessel to melt the compound semiconductor material sealed in the airtight vessel, and thereafter decreasing the temperature of the airtight vessel to solidify the melted compound semiconductor material to grow a compound semiconductor crystal containing a predetermined amount of carbon.
The carbon oxide gas includes at least one type of gas selected from the group consisting of CO gas and CO 2 gas.
In growing the crystal, preferably the melted compound semiconductor material is at least partially kept in contact with boron oxide (B 2 O 3 ).
In growing the crystal, more preferably the melted compound semiconductor material has its upper surface entirely covered with boron oxide (B 2 O 3 ).
Preferably, the boron oxide (B 2 O 3 ) has a water content of no more than 300 ppm, more preferably no more than 100 ppm.
Preferably, variation of the water content of the boron oxide (B 2 O 3 ) is controlled to fall within a range from +20% to −20%.
In accordance with the present invention, the carbon oxide gas sealed in the airtight vessel preferably has a partial pressure of 0.1 to 100 Torr at 25° C.
In accordance with the present invention, carbon oxide gas is preferably sealed in an airtight vessel according to an expression:
C CARBON =a×P 0.5 (1),
wherein C CARBON (cm −3 ) represents carbon concentration in a compound semiconductor crystal, P (Torr) represents partial pressure of the carbon oxide gas, and a represents any coefficient.
In expression (1) coefficient a preferably ranges from 0.25×10 15 to 4×10 15 cm −3 /Torr 0.5 , more preferably 0.5×10 15 to 2×10 15 cm −3 /Torr 0.5 .
In accordance with the present invention, preferably the step of subjecting the airtight vessel to a vacuum heat treatment is also provided before the step of sealing carbon oxide gas in the airtight vessel.
The vacuum heat treatment is preferably provided at a temperature of no more than 350° C.
In accordance with the present invention, at least the internal wall of the airtight vessel and at least the outer surface of the contents of the airtight vessel other than the compound semiconductor material and the boron oxide are preferably formed from a material which does not contain carbon.
The material which does not contain carbon includes at least one material selected from the group consisting, e.g., of quartz, silicon nitride, boron nitride, pyrolytic boron nitride and alumina.
In accordance with the present invention, the gas-impermeable airtight vessel can at least partially be formed from quartz.
Preferably, the portion formed from quartz has a thickness of no less than 1.5 mm.
In growing the crystal, preferably the portion formed from quartz is controlled to have a temperature of at most 1270° C.
In accordance with the present invention, in growing the crystal a space behind a raw-material melt of melted compound preferably has its most heated portion and its least heated portion with a temperature difference of no more than 300° C. therebetween.
In accordance with the present invention, the space behind the raw-material melt is preferably larger, more preferably no less than twice larger in volume than the space on the side of the raw-material melt.
A method of preparing a compound semiconductor crystal in accordance with the present invention is applicable to preparing a compound semiconductor crystal of GaAs.
In another aspect, the present invention provides a compound semiconductor crystal prepared in accordance with the above-described method of preparing a compound semiconductor crystal, having a carbon concentration of 0.1×10 15 cm −3 to 20×10 15 cm −3 .
In accordance with the present invention, the compound semiconductor includes GaAs.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows preparation of a GaAs crystal as one example of a method of preparing a compound semiconductor crystal in accordance with the present invention.
FIG. 2 shows a position of a sample for FTIR measurement in a crystal.
FIG. 3 is a graph of carbon concentration in a GaAs crystal versus CO gas concentration in a conventional LEC furnace.
FIG. 4 shows one example of conventional GaAs crystal growth equipment for the LEC method.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is based on a method of preparing a compound semiconductor crystal in a sealed system (a system incapable of supplying a gas from outside an airtight vessel) using a gas-impermeable airtight vessel.
In accordance with the present invention, carbon oxide gas of a predetermined partial pressure as well as a compound semiconductor provided as a raw material are sealed in a gas-impermeable airtight vessel, the temperature of the airtight vessel is increased to melt the compound semiconductor material and the temperature of the airtight vessel is then decreased to solidify the melted compound semiconductor material to grow a compound semiconductor crystal to thereby allow the compound semiconductor crystal to be doped with carbon with high reproducibility.
As the carbon oxide gas, a stable CO or CO 2 gas can be used to allow the crystal to be doped with carbon in particularly high reproducibility.
In growing the crystal, preferably at least a portion of the melt of the compound semiconductor material can be kept in contact with boron oxide (B 2 O 3 ) and more preferably the upper surface of the melt can be entirely covered with boron oxide (B 2 O 3 ) to prevent other elements of impurities from being introduced into the melt so as to further enhance the reproducibility of the carbon concentration of the crystal.
To reduce an influence of the water contained in B 2 O 3 to control the carbon concentration of the crystal in high reproducibility, B 2 O 3 preferably has a water content of no more than 300 ppm, more preferably no more than 100 ppm. To reduce an influence of variation of the water content of B 2 O 3 to control the carbon concentration of the crystal in high reproducibility, the variation of the water content of B 2 O 3 is preferably controlled to fall within a range from +20% to −20%.
To obtain a practical carbon concentration for a compound semiconductor crystal, i.e., 0.1×10 15 cm −3 to 20×10 −15 cm −3 , carbon oxide gas requires a partial pressure of 0.1 to 100 Torr at 25° C., substantially establishing the relation: (carbon concentration in a compound semiconductor crystal)=a×(partial pressure of carbon oxide gas) 0.5 , wherein a represents any coefficient and is preferably 0.25×10 15 to 4×10 15 cm −3 /Torr 0.5 , more preferably 0.5×10 15 to 2×10 15 cm −3 /Torr 0.5 .
Conventionally in the prior art, the ambient gas has been represented or quantified by its concentration. For example, an ambient gas for GaAs crystal growth typically has a pressure of 1 to 30 atm. When an ambient gas of 1 atm and an ambient gas of 30 atm which have the same gas concentration are converted into terms of partial pressure, the partial pressure of the latter is 30 times larger than that of the former.
The inventors of the present invention have found that in a method of preparing a compound semiconductor crystal in a sealed system (a system incapable of supplying a gas from outside an airtight vessel) using a gas-impermeable airtight vessel, the carbon concentration in the crystal is correlated to the partial pressure of the carbon oxide gas sealed in the airtight vessel rather than the concentration of the carbon oxide gas sealed in the airtight vessel.
Herein the carbon oxide gas sealed in the airtight vessel is represented in the partial pressure at 25° C., since the partial pressure of the carbon oxide gas increases as the temperature of the airtight vessel is increased in growing a crystal. Since a GaAs crystal has a melting point of approximately 1238° C., the partial pressure of the carbon oxide gas sealed at a room temperature (of 25° C.) is considered to be increased by approximately five times during the crystal growth.
While in accordance with the present invention, carbon oxide gas having a predetermined partial pressure is sealed in an airtight vessel, carbon oxide gas may be sealed together with another gas, which can include inert gases, such as helium, neon, argon, krypton, xenon, and nitrogen gas. When only carbon oxide gas is sealed in the vessel, it has a concentration of 100%. When carbon oxide gas is sealed, e.g., together with any of the above gases of 50%, the carbon oxide gas has a concentration of 50%. It should be noted, however, that if carbon oxide gas is thus sealed together with any of the above gases, the expression: (carbon concentration in a compound semiconductor crystal)=a×(partial pressure of carbon oxide gas) 0.5 is sufficiently satisfied by the coefficient a preferably having the value of 0.25×10 15 to 4×10 15 cm −3 /Torr 0.5 , more preferably 0.5×10 15 to 2×10 15 cm −3 /Torr 0.5 .
Removal of water absorbed in the airtight vessel further enhances the reproducibility of the carbon concentration in the crystal. Accordingly it is preferable to apply a vacuum heat treatment to the airtight vessel before it is sealed. The vacuum heat treatment applied immediately before the vessel is sealed is applied preferably at no more than 350° C., at which temperature B 2 O 3 does not soften or deform.
To control the carbon concentration of the crystal in high reproducibility, at least the internal wall of the airtight vessel and at least the outer surface of the contents of the vessel other than the compound semiconductor as a raw material and boron oxide are preferably formed from a material which does not contain carbon, so that further generation of carbon oxide gas can be prevented in the vessel. More specifically, the airtight vessel is preferably formed from a material which does not contain carbon, or the vessel preferably has its internal wall coated with a material which does not contain carbon. It is also preferable that the contents of the airtight vessel other than the compound semiconductor material and boron oxide be formed from a material which does not contain carbon or that the contents have the outer surface coated with a material which does not contain carbon. The material which does not contain carbon is preferably quartz, silicon nitride, boron nitride, pyrolytic boron nitride or alumina.
Furthermore, the gas-impermeable airtight vessel of the present invention can at least partially be formed from quartz, since quartz has superior airtightness and hardly reacts with elements forming the compound semiconductor or carbon oxide gas.
In accordance with the present invention, carbon oxide gas having a predetermined partial pressure is sealed in a gas-impermeable airtight vessel. However, when the airtight vessel is deformed and its internal volume is changed, the partial pressure of the sealed carbon oxide gas is changed and the carbon concentration of the resulting compound semiconductor crystal will deviate from a targeted carbon concentration.
The strength of quartz is reduced at high temperature and is significantly reduced at a temperature at which a GaAs crystal is grown, i.e., 1238° C. If a gas-impermeable airtight vessel is at least partially formed from quartz, the difference between the pressure internal to the vessel and that external to the vessel deforms the quartz portion of the vessel and thus changes the internal volume of the vessel. The inventors of the present invention have found that as the vessel's quartz portion is increased in thickness, deformation of the quartz portion is reduced at high temperatures and variation in the vessel's internal volume is thus reduced. The inventors have also found that the quartz portion of the vessel preferably has a thickness of no less than 1.5 mm, more preferably no less than 2.0 mm, still more preferably no less than 2.5 mm.
The inventors have also found that as temperature is decreased, deformation of quartz is reduced and variation in the vessel's internal volume is reduced. The inventors have also found that the quartz portion of the vessel preferably has a temperature of at most 1270° C., more preferably at most 1260° C., further still more preferably at most 1250° C.
In accordance with the present invention, carbon oxide gas of a predetermined partial pressure is sealed in a gas-impermeable airtight vessel. When the temperature of the airtight vessel varies, however, the partial pressure of the sealed carbon oxide gas changes and the carbon concentration of the resulting compound semiconductor crystal thus deviates from a targeted carbon concentration.
In particular, the hollow gas-filled space on the side of the raw-material melt, more specifically, the space between the crucible 5 and the ampoule 8 located below the interface (labeled A in FIG. 1) of raw-material melt 2 and boron oxide 4 , i.e., the space on the side of the seed crystal has its temperature reduced as crystal growth proceeds. When this hollow space on the side of the raw-material melt is large in volume, the average temperature and hence partial pressure of the carbon oxide gas in the airtight vessel are reduced significantly.
In contrast, the temperature of the hollow gas-filled space behind the raw-material melt, i.e., the hollow gas-filled space within the ampoule 8 located above interface A can be controlled regardless of crystal growth. Thus, controlling the temperature of this space behind the raw-material melt, can prevent reduction of the average temperature of the carbon oxide gas in the airtight vessel and reduce reduction of the partial pressure of the carbon oxide gas in the vessel. Reducing the temperature difference between the most and least heated portions of the space behind the raw-material melt can reduce reduction of the partial pressure of the carbon oxide gas in the vessel. The temperature difference between the most and least heated potions of the space behind the melt is preferably no more than 300° C., more preferably no more than 200° C., still more preferably no more than 100° C.
When the hollow gas-filled space behind the raw-material melt is larger in volume than the hollow gas-filled space on the side of the raw-material melt, this can further reduce the reduction of the partial pressure of the carbon oxide gas in the vessel that is caused when the average temperature of the gas in the vessel is reduced. The space behind the raw-material melt is preferably no less than twice, more preferably no less than three times, still more preferably no less than four times larger in volume than that on the side of the raw-material melt.
Furthermore, the method of the present invention is particularly applicable to preparation of GaAs crystal.
Hereinafter, an example of actual preparation of a GaAs crystal in accordance with the present invention will now be described in detail.
FIG. 1 shows an exemplary method of preparing a compound semiconductor crystal in accordance with the present invention, using a gas-impermeable airtight vessel formed from quartz (referred to as a “quartz ampoule” hereinafter) to prepare a GaAs crystal.
Referring to FIG. 1, a GaAs seed crystal 3 of orientation <100>, 5 kg of GaAs 2 as a raw material, and 50 g of boron oxide 4 (referred to as “B 2 O 3 ” hereinafter) with a water content of 70 ppm were initially placed in a crucible 5 formed from pyrolytic boron nitride (referred to as “pBN” hereinafter) and having an inner diameter of 80 mm and also having a cylindrical portion of approximately 30 cm in length, and crucible 5 was housed in a quartz ampoule 8 of 2.5 mm thick. The space behind the raw-material melt placed in quartz ampoule 8 , i.e., that located above the interface denoted by arrow A in FIG. 1 was adapted to be four times larger in volume than the space on the side of the raw-material melt, i.e., that located below interface A).
Quartz ampoule 8 was vacuumed to 1×10 −6 Torr and also heated to 300° C. to remove water adsorbed on the internal wall of ampoule 8 and the raw material. Then, CO 2 gas 7 of 3 Torr was introduced and sealed in ampoule 8 . Ampoule 8 was mounted on a support 9 and thus set internal to a vertical heater 6 provided in a chamber 10 , and the temperature of heater 6 was increased to melt GaAs material 2 and an upper portion of seed crystal 3 .
Then the temperature profile of the heater was adjusted to decrease the temperature from the side of the seed crystal 3 and the entirety of raw-material melt 2 was thus solidified to grow a crystal. In the crystal growth, the highest temperature of ampoule 8 was also controlled not to exceed 1250°. Furthermore, the temperature of an upper portion of ampoule 8 was controlled so that the space located behind the raw-material melt, i.e., that located above interface A shown in FIG. 1 had its most heated portion and its least heated portion with a temperature difference of no more than 100° C. therebetween.
The temperature was reduced to a room temperature and quartz ampoule 8 was then cut and opened to separate a GaAs crystal from crucible 5 .
The resulting GaAs crystal had a diameter of 80 mm, and the portion having the diameter of 80 mm was approximately 18 cm long. A sample of 5 mm thick for measurement of carbon concentration was cut out at the position of a shoulder of the crystal (fraction solidified: g of 0.1). FIG. 2 shows the position of the shoulder of the crystal from which the sample was cut out. Fourier Transform Infrared Spectroscopy (FTIR) was used to measure the concentration of the carbon substituted at an arsenic site (referred to as “C As ” hereinafter). The measured C As concentration was 2.1×10 15 cm −3 .
The C As concentration in the crystal grown under a different partial pressure of sealed CO 2 was similarly measured. The measured results are provided in Table 1.
TABLE 1
Partial pressure of sealed CO 2 gas and
C As concentration in GaAs crystal
Partial pressure of sealed CO 2 gas
C As concentration in GaAs crystal
(Torr)
(cm −3 )
0.5
0.8 × 10 15
3.0 (embodiment)
2.1 × 10 15
4.5
2.7 × 10 15
6.0
3.1 × 10 15
10.0
4.0 × 10 15
30.0
6.5 × 10 15
60.0
10.0 × 10 15
100.0
13.2 × 10 15
It has been found from the results presented in Table 1 that the relation: (carbon concentration in a compound semiconductor crystal)=a×(partial pressure of carbon oxide gas) 0.5 can be substantially established, wherein a≈1.25×10 15 cm −3 /Torr 0.5 under the conditions of the first embodiment.
As a result of experimentally growing a crystal under various conditions, it has been revealed that to obtain a value of a practical carbon concentration in a compound semiconductor crystal, i.e., 0.1×10 15 to 20×10 15 cm −3 , a preferable partial pressure of carbon oxide gas is 0.1 to 100 Torr at 25° C., substantially establishing the relation: (carbon concentration in a compound semiconductor crystal)=a×(partial pressure of carbon oxide gas) 0.5 and that coefficient a preferably ranges from 0.25×10 15 to 4×10 15 cm −3 /Torr 0.5 , more preferably 0.5×10 15 to 2×10 15 cm −3 /Torr 0.5 , since the coefficient can vary with the conditions of the experiment carried out.
It has also been found as a result of an experiment using B 2 O 3 with its water content varied from 30 to 1000 ppm that the carbon concentration in the crystal can be controlled in higher reproducibility when the water content of B 2 O 3 is lower and has less variation. Satisfactory reproducibility of the carbon concentration in crystal is achieved when the water content of B 2 O 3 is no more than 300 ppm, particularly no more than 100 ppm and the variation of the water content of B 2 O 3 is controlled to fall within a range from +20% to −20%. With CO 2 gas replaced with CO gas, a similar result has also been obtained in a similar manner.
Thus, the present invention can provide a method of preparing a compound semiconductor crystal in a sealed system (a system incapable of supplying a gas from outside an airtight vessel) using a gas-impermeable airtight vessel to allow the compound semiconductor crystal to be doped with carbon in high reproducibility.
Furthermore, carbon oxide gas of a predetermined partial pressure sealed in the gas-impermeable airtight vessel together with compound semiconductor provided as a raw material allows a compound semiconductor crystal with a desired carbon concentration and hence with a desired electrical characteristic to be prepared in high reproducibility, since the electrical characteristic of the compound semiconductor crystal depends on the carbon concentration of the crystal.
Thus the present invention can provide satisfactory crystal yield.
Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims. | A method of preparing a compound semiconductor crystal is able to dope the crystal with carbon with high reproducibility. The method includes the steps of sealing a carbon oxide gas of a predetermined partial pressure and a compound semiconductor material in a gas-impermeable airtight vessel, increasing the temperature of the vessel to melt the compound semiconductor material sealed in the vessel, and then decreasing the temperature of the vessel to solidify the melted compound semiconductor material to grow a compound semiconductor crystal containing a predetermined amount of carbon. With this method, a compound semiconductor crystal with a carbon concentration of 0.1×10 15 cm −3 to 20×10 15 cm −3 is prepared with high reproducibility. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to multi-stage gas-fired furnaces and, more particularly, to a method for proving the high-heat pressure switch in a multi-stage gas-fired furnace.
2. Description of the Prior Art
During certain situations in the operation of a multi-speed furnace, problems can arise in that the high-fire pressure switch (HPS) may fail to close or may, due to an increase in pressure in its immediate vicinity, open while in high-fire. The former situation can occur in longer length vent systems at high altitude and on furnaces with higher rise ranges. The latter situation can occur when the furnace is already operating in high-fire mode as previously requested, and may be caused, for example, by a high wind gust impinging a horizontal vent. In either case, when nothing is done about the HPS being open, the system will normally attempt to satisfy the thermostatically communicated high-heat demands using low heat if the HPS does not close. If successful, the furnace would be required to run for an excessive period of time in low-fire mode in order to satisfy the thermostat, and it will take longer than desirable for the temperature to reach the pre-set comfort level. When the furnace is recovering from night set-back the loss of high-fire heat may result in the system taking many hours to regain the desired temperature. In some instances, heat delivered in the low-fire mode may not be sufficient to satisfy the thermostat and the temperature in the conditioned space will become low enough to cause occupant discomfort.
In the prior art, in particular copending U.S. patent application Ser. No. 08/090,332, assigned to a common assignee, an interlock is provided between the high-fire pressure switch and the high-fire solenoid to prevent the high-fire solenoid from being energized when the furnace is in low fire mode. Twenty four volt thermostat power is denied to the high-fire pressure switch and high-fire solenoid whenever there is a call for low heat.
In U.S. Pat. Nos. 4,982,721, 5,027,789 and 5,186,386 all to Lynch, the system attempts to deal with the problem of the high-fire pressure switch remaining closed (causing the system to run in high-fire mode with respect to the amount of fuel delivered) when the inducer fan is running at low speed--that is the combustion air is being delivered at a volume appropriate for low-fire mode. This is done before gas ignition is attempted by running the inducer fan on low speed for 1 minute, turning off the inducer fan for 4 minutes, and running the inducer fan on high speed for 15 seconds before starting another cycle.
None of these documents address the problem of the high-fire pressure switch failing to close when it should, or reopening during high-fire mode operation.
SUMMARY OF THE INVENTION
It is therefore a primary object of the present invention to provide a method for closing the high-heat pressure switch in a multi-stage gas-fired furnace.
It is a further object of this invention to provide a method for handling an inappropriately open state of the high-fire pressure switch.
It is yet a further object of this invention to provide a method for handling the failure of closure of the high-fire pressure switch when the furnace thermostat is calling for high-fire.
It is still another object of this invention to provide for heating of the conditioned space when the high-fire pressure switch fails repeatedly to close.
It is yet another object of this invention to provide a method for handling the improper opening of the high-fire pressure switch while the furnace thermostat is operating in high-fire mode.
It is still another object of this invention to provide for heating of the conditioned space when the high-fire pressure switch fails to reclose after having opened during furnace operation in high-fire mode.
These and other objects of the present invention are attained by, in a two-stage furnace system, including a thermostat, at least one gas burner with a low and high-fire operating capability, an inducer fan having low and high speed operating settings, and a high-fire pressure switch, a method for handling the high-fire pressure switch being in an inappropriately open condition. The method has the steps of: determining whether the thermostat is issuing a call for high heat and if it is, determining if the high-fire pressure switch is open. If the high-fire pressure switch is open, waiting a predetermined time, determining if the high-fire pressure switch is still open and if it is, then completing a furnace shutdown sequence, initiating an ignition sequence in high-speed inducer pre-purge mode, determining if the high-fire pressure switch remains open, and if so, running the gas burner in low-fire mode. If, while these steps are being performed, the high-fire pressure switch closes, the system is run in high-fire mode.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of these and other objects of the present invention, reference is made to the detailed description of the invention which is to be read in conjunction with the following drawings, wherein:
FIG. 1 is a schematic diagram of the two stage furnace illustrative of the present invention.
FIG. 2 is a flow chart of the process for handling the HPS not closing upon a call for high-fire heat.
FIG. 3 is a flow chart of the process for handling the HPS opening during high-fire operation.
FIG. 4 is a graphical illustration of the furnace system pressure and its effect on the status of the high-fire pressure switch as a function of time, during a normal call for high heat with proper closure of the HPS.
FIG. 5 is a graphical illustration of the furnace system pressure and its effect on the status of the high-fire pressure switch as a function of time, when the high-fire pressure switch fails to close and the handling thereof according to the instant invention.
FIG. 6 is a graphical illustration of the furnace system pressure and its effect on the status of the high-fire pressure switch as a function of time during normal operation in high-fire mode where the HPS remains properly closed.
FIG. 7 is a graphical illustration of the furnace system pressure and its effect on the status of the high-fire pressure switch as a function of time during normal operation in high-fire mode where the HPS opens and the system attempts correction according to the instant invention.
DETAILED DESCRIPTION OF THE INVENTION
Turning now to the Drawing and particularly, FIG. 1 thereof, there is shown a schematic of a typical two stage furnace such as may be controlled by the process of the instant invention, the furnace schematic being indicated generally as 2. The present invention is dependent upon the microprocessor 12 which controls the operation of the furnace generally and in particular the process of this invention, microprocessor 12 having located therein memory and the control program therefore. Although the microprocessor 12 is shown herein with respect to a particular furnace system, the invention encompasses other arrangements which involve the operation of a two-stage furnace.
Microprocessor 12 is located on furnace control 1 which also holds transformer 11, which functions to convert some of the high voltage power received by the control 1 to the low voltage power needed for the flame rollout switch 6, limit switch 7, low-fire pressure switch 8, auxiliary limit switch 9, draft safeguard switch 10, high-fire pressure switch relay 13, and high-fire pressure switch 14, all of whose functions in controlling the gas valve will be described hereinafter.
In the normal operation of the furnace, a call for heat is issued by the thermostat 3. The thermostat 3 call for heat is relayed to microprocessor 12. This call may be either for low-fire heat in which case the R-W1 connection (not shown), discussed hereinafter with respect to FIG. 2, is closed and the R-W2 (not shown) connection is open. Or it may be for high-fire heat in which case both the R-W1 and R-W2 connections are closed.
If there is a call for heat, the inducer starts and, if the pressure switch(es) is(are) closed, the ignition sequence starts and the hot surface ignitor 5 is activated and serves to ignite the fuel gas. Combustible fuel gas is delivered into the system through the gas valve 15 via a line from fuel gas source 22. The amount of fuel gas delivered is controlled by gas valve 15. Gas valve 15 contains high-fire 26 and low-fire solenoids 25 that control the proper rate of gas delivery for high-fire and low-fire operation respectively. The low-fire solenoid is controlled by microprocessor 12, while the high-fire solenoid is controlled directly by the high-fire pressure switch 14. The high-fire pressure switch 14 determines the presence or absence of sufficient combustion air for the high-fire heating operation, being normally closed when there is sufficient combustion air and open when there is not.
The fuel gas is mixed with combustion air provided from a combustion air source 23, ignited at GB (gas burner(s)) 24 and directed to heat exchanger(s) 17 which transfer the heat of combustion to the air which circulates through the conditioned space. Two speed inducer motor 16 draws the combusted fuel/air mixture through the heat exchanger(s) 17 and delivers the cooled mixture to the vent system 21 so as to vent it from the building.
Simultaneously, multi-speed blower motor 18 (in this case a 4-speed one) moves circulating interior air from the return air plenum 19 through the furnace 2, over the heat exhanger(s) 17, and finally supplies it in its heated state through supply air ducts 20 as supply air back to the conditioned space (not shown).
When the call is specifically for high heat, the high-fire pressure switch relay 13 is closed by the microprocessor 12. When open, the high-fire pressure switch relay 13 interrupts electrical current to both the high-fire pressure switch 14 and the high-fire solenoid 26 on gas valve 15.
Hardware is supplied in order to detect and allow the system to correct for a number of possible error conditions of the furnace system 2. Flame rollout switch 6 detects unacceptably high burner assembly temperatures and functions to halt the heating operation when this situation occurs. Heating is also terminated when the limit switch 7 detects unacceptably hot air passing over the heat exchangers and to the conditioned space.
The low-fire pressure switch 8 operates analogously to the high-fire pressure switch 14 in that it detects whether or not there is sufficient combustion air for the low-fire heating operation. Low-fire pressure switch 8 is not as likely to be opened due to transient conditions as is high-fire pressure switch 14.
The auxiliary limit switch 9 functions typically in downflow and horizontally installed furnaces (as compared with upflow furnaces) to detect whether the multi-speed blower is not operating. In this case the heated air tends to flow in the reverse direction. When this situation is detected the auxiliary limit switch 9 opens, signalling the system to halt heating operations. Heating is also halted when the draft safeguard switch 10 detects an obstruction in the furnace vent system.
The process for detecting and handling the situation where the high-fire pressure switch (HPS) 14 fails to close when high-fire operation is requested by the system from a steady-state low-fire condition, is shown in FIG. 2. Initially, in step 100, R-W1 (the thermostat connection which indicates a call for low-fire heat) is closed and R-W2 (the thermostat connection which indicates a call for high-fire heat) is open. The low-fire pressure switch (LPS) 8 is closed, while the high-fire pressure switch 14 can be either open or closed. In step 102 a determination is made as to whether high heat is being called for. If so, then in step 104 the inducer is set to high speed and in 106a determination is made as to whether HPS 14 is closed. If so then in 108the gas flow is set to high, providing high heat. Then in 110HPS 14 is tested to determine if it is closed. If so, then in 112a determination is made as to whether the thermostat is satisfied. If it is not then the routine loops back to 108so that HPS 14 is essentially continuously checked until it is either open or the thermostat is satisfied.
Returning now to steps 110and 106,if HPS 14 is not closed upon either of these determinations, then in 114 the system waits for up to 2minutes for the HPS 14 to close. The choice of two minutes is based on a compromise between allowing the high-fire pressure switch 14 sufficient time to close, and not delaying the delivery of high-fire heat so long as to cause discomfort to the occupant(s) of the conditioned space. Any time value in the range of 0seconds to 30 minutes would be reasonable. In 116the state of HPS 14 continues to be tested. If it is closed, the situation has normalized and control returns to 108.If, on the other hand, it is still open, then an attempt to close it is made in 118.The main gas valve is de-energized and the inducer and blower shut down timers are started, for the normal inducer post-purge and blower-off delays. When the inducer and blower have been shut down, the high speed inducer is energized. This initiation of the ignition sequence in high-speed inducer pre-purge should result in the high-fire pressure switch 14 closing, since the unfired cold purge heat exchanger pressure drop, with the inducer in high speed, is greater than the fired, low-fire heat exchanger pressure drop with the inducer in high speed.
After this attempt to close the high-fire pressure switch 14, its status is tested in 120.If it is closed, then in 122the ignition sequence for high-fire heat is initiated and the process loops back to 108.If HPS 14 is not closed then in 124low-fire operation is provided using the high-fire heating blower speed, so that there is heating to the conditioned space.
While operating in the low-fire mode the system continuously tests whether HPS 14 has closed in 126, returning control to 108if it has, and testing to see if the thermostat is satisfied in 128if it has not. If the thermostat is not satisfied then the system loops back to provide additional low-fire heat in 124,while if the thermostat is satisfied the process is terminated in 150. Shut down 150is alternatively carried out if the thermostat satisfied test of 112is met.
Returning now to 102,if there is no call for high heat then provision of low-fire heat is continued in 140, and a check is made in 142to see if the thermostat is satisfied. If it is, then the 150termination is performed and if it is not, control loops back to 102 essentially continuously monitoring for a call for high heat.
In summary, if the HPS 14 is not closed upon a call for high heat then, after a delay, if the HPS remains open, the system goes through a normal shutdown and a pre-purge sequence in an attempt to create a pressure differential between the high-fire pressure switch 14 and the burner area, sufficient to close the HPS 14. If this is not achieved, then heating is provided to the conditioned space using low-fire heating with high-fire heating blower speed until such time as either the thermostat call for heat is satisfied or the high-fire pressure switch 14 is closed, permitting high-heat operation.
The relationship of the heat exchanger pressure drop to furnace functioning over time under normal conditions is shown in FIG. 4. In FIG. 4 and all succeeding figures, HM is the high-fire pressure switch closure point, HB is the high-fire pressure switch open point, LM is the low-fire pressure switch closure point, and LB is the low-fire pressure switch open point,
Normally then, within less than two minutes of the call for high-heat, from a low-heat operating mode, there is sufficient pressure drop in the region of the high-fire pressure switch 14, caused by the inducer motor operating at high speed and providing sufficient air to support the high-fire gas input rate, to cause the HPS 14 to close. Once it is closed, it remains closed, and the system proceeds into high-fire until such time as the thermostat is satisfied.
FIG. 5 shows the situation where there is a call for high-fire heat while in low-heat, but there is an insufficient pressure drop for the HPS 14 to close. After two minutes, normal shutdown procedures are initiated. Once the shutdown is complete, a normal unfired startup begins with high speed inducer operation, and thereafter either the HPS 14 will close as is shown in line A or fail to close again as shown in line B.
FIG. 3 shows the process for detecting and handling the situation where the high-fire pressure switch 14 opens when steady-state high-fire operation is in process. Initially, in 200,R-W1 and R-W2 are both closed, as are the low-fire pressure switch 8 and the high-fire pressure switch 14.
In 202a determination is made as to whether or not the thermostat is satisfied. If it is, the shutdown process of 250takes place; otherwise the HPS 14 is tested in 204.If the HPS 14 is closed, then in 206the gas flow remains set to high, providing high heat. Next a determination is made in 208as to whether the thermostat is satisfied. If so, control passes to the shutdown process of 250.If not the status of the HPS 14 is tested again in 204.
If the HPS 14 test of 204showed the HPS 14 open, then in 210the system waits for up to 2minutes. As in the earlier discussion, the choice of two minutes is based on a compromise between allowing the high-fire pressure switch 14 sufficient time to close and not delaying the delivery of high-fire heat so long as to cause discomfort to the occupant(s) of the conditioned space. Any time value in the range of 0seconds to 30minutes would be reasonable. In 212the state of HPS 14 is again tested. If it is closed, the situation has normalized and control returns to 206.If, on the other hand, it is still open, then an attempt to close it is made in 214.The main gas valve is de-energized and the inducer and blower shut down timers are started for the normal inducer post-purge and blower-off delays. When the inducer and blower have been shut down, the high speed inducer is energized. This initiation of the ignition sequence in high-speed inducer pre-purge should result in the high-fire pressure switch 14 closing, since the unfired cold purge heat exchanger pressure drop, with the inducer in high speed, is greater than the fired, low-fire heat exchanger pressure drop with the inducer in high speed.
After this attempt to close the HPS 14, its status is tested again in 216and, if it is closed, the ignition sequence for high-fire is undertaken in 218and high-fire heat is provided in 220.The HPS 14 is then tested in 222.If it is not closed, then the two minute wait of 210is implemented. If it is closed, a determination is made in 224as to whether the thermostat is satisfied. If so, then the shut down process of 250takes place and, if not, control loops to 220.
Returning now to 216,if the test there shows that the HPS 14 is not closed, then low-fire operation is continued in 230using the high-fire heating blower speed, so that there is heating to the conditioned space. Next the HPS 14 status is tested again in 232.If it is closed, control passes to 220providing high heat. If it is open, a determination is made as to whether the thermostat is satisfied in 234.If it is not, the system continues providing low heat in 230,while if it is, the system shuts down normally in 250.
In summary, if the HPS 14 opens while the system is providing high heat then, after a delay, if the HPS is still open, the system goes through a normal shutdown then a pre-purge sequence in an attempt to create a pressure differential between the high-fire pressure switch 14 and the burner area, sufficient to close the HPS 14. If this is not achieved, then heating is provided to the conditioned space using low-fire heating with high-fire heating blower speed until such time as either the thermostat call for heat is satisfied or the high-fire pressure switch 14 is closed.
FIGS. 6 and 7 contrast two different situations where the furnace is performing in high-fire mode. The normal situation is shown in FIG. 6 where the HPS 14 remains properly closed and high heat is provided continuously until such time as the thermostat is satisfied.
The case where the HPS 14 opens, whether due to a high wind gust impinging a horizontal vent or some other cause, is shown in FIG. 7. The untoward event causes the HPS 14 to open, and for two minutes the system continues operation with low-gas being provided and the high-speed inducer operation. If the HPS 14 does not close by then, shutdown procedures are initiated. Once the shutdown is complete, a normal unfired startup begins with high speed inducer operation, and thereafter either the HPS 14 will close as in line C or fail to close again as in line D.
While these examples have been explained with reference to two stage heating it should be noted that with adjustments it can also deal with extra stages in multi-stage furnaces.
While this invention has been explained with reference to the structure disclosed herein, it is not confined to the details set forth and this application is intended to cover any modifications and changes as may come within the scope of the following claims: | In a two-stage furnace system, including a thermostat, at least one gas burner with a low and high-fire operating capability, an inducer fan having low and high speed operating settings, and a high-fire pressure switch, a method for handling the high-fire pressure switch being in an inappropriately open condition. The method has the steps of: determining whether the thermostat is issuing a call for high heat and, if it is, determining if the high-fire pressure switch is open. If the high-fire pressure switch is open, waiting a predetermined time, determining if the high-fire pressure switch is still open and, if it is, completing a furnace shutdown procedure, then initiating a normal shutdown, then an ignition sequence in high-speed inducer pre-purge mode, determining if the high-fire pressure switch remains open, and if so, running at least one gas burner in low-fire mode. If, while these steps are being performed, the high-fire pressure switch closes, running the system in high-fire mode. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates to a system and method for selectively creating an airflow sufficient to entrain an anticipated length of the thread and capturing the length of thread from the airflow to provide for selective removal of a captured thread length from the airflow.
BACKGROUND OF THE INVENTION
[0002] U.S. Pat. No. 6,817,306 discloses a cut looper thread disposal means at a side location of the needle and orthogonal to the sewing direction. This disposal means includes a thread suction tube (thread suction device), a thread pick and pull cylinder, and a looper thread presser foot. The thread suction tube sucks and collects the part of the looper thread cut by the stationary blade, at a single location, that is, in the vicinity of a suction port. The thread pick and pull cylinder picks at a pick part of the looper thread and pulls it into the vicinity of the suction part of the suction tube.
[0003] However, this machine mounted, automated device is not applicable to individual users. Further, this device is integral with the sewing machine and is not compatible with any retrofit of the machine. That is, the device has limited applicability for individual users.
BRIEF SUMMARY OF THE INVENTION
[0004] The present disclosure provides a thread capturing apparatus including a housing having an inlet and an outlet, the inlet at least partially defined by a throat having a converging section; a grill removably connected relative to the housing, the grill located proximal to the throat; a motor within the housing; a fan connected to the motor and disposed within the housing, the fan selected to create an airflow through the housing from the inlet to the outlet; and a proximity sensor initiating rotation of the fan in response to a portion of the user being located within (i) a substantially predetermined distance from the housing or (ii) a detecting region/volume of the proximity sensor.
[0005] In a further configuration, the housing has a removable wall selectively providing access to the fan independent of the inlet and the outlet of the housing. Further, the housing, the motor, and the fan can be sized to entrain a thread within the created air flow through the throat.
[0006] A method is provided including the steps of initiating an airflow through a converging throat into a housing in response to locating a portion of the thread within a given distance or volume from the converging throat or a grill adjacent to the converging throat, at least a portion of the airflow passing through the grill; at least partially entraining the thread in the airflow through the grill to engage the thread on the grill; and automatically terminating airflow through the converging throat.
[0007] It is further contemplated, the airflow can be initiated in response to one of a portion of the user and the thread being disposed within a given distance from the throat or within a detecting volume of the proximity sensor.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
[0008] FIG. 1 is a perspective view of the thread capturing device, with a portion of the device removed for illustration purposes; and
[0009] FIG. 2 is an exploded perspective view of the thread capturing device.
[0010] FIG. 3 is a perspective view of an alternative configuration of the device.
DETAILED DESCRIPTION OF THE INVENTION
[0011] The thread capturing device 10 includes a housing 20 having an inlet 22 and an outlet 24 ; a fan assembly 40 and a removable grill 60 .
[0012] The housing 20 generally includes an enclosing body 30 such as having top 31 , bottom 32 , left 33 , right 34 , front 35 and back 36 walls. It is contemplated the top 31 , bottom 32 , left 33 , right 34 , front 35 and back 36 walls can be individually formed or as many as five of the walls can be integrally formed such as by casting or molding.
[0013] One of the walk includes the inlet 22 and another wall includes the outlet 24 , As seen in FIG. 1 , the top wall 31 or lid includes the inlet 22 and the back wall 36 includes the outlet 24 .
[0014] In one configuration of the housing 20 , as seen in FIG. 2 , the side walk 33 , 34 include opposing retaining channels 38 on an inside surface of the walls.
[0015] The housing 20 can be formed from a variety of materials including metals, plastics, composites, or laminates. A representative size of the housing 20 is approximately 4 inches wide, approximately 8 inches long, and approximately 8 inches tall.
[0016] The inlet 22 has an area of approximately 16 square inches and the outlet 24 has at least approximately 16 square inches.
[0017] As seen in FIG. 2 , the lid or top wall 31 can be removably attached to the remaining walls for accessing the interior of the housing 20 and the fan assembly 40 .
[0018] As seen in FIG. 2 , the fan assembly 40 includes a plurality of blades 42 , a motor 44 and an engaging collar 46 , wherein peripheral edges of the engaging collar are sized to be received within the retaining channels 38 of the side walls 33 , 34 , thereby locating the fan assembly relative to the housing 20 .
[0019] The fan blades 42 are selected to provide a relatively high flow at a given rotation rate. Satisfactory fan blades 42 have been found to have a dimension of approximately 2.5 inches. The fan blades 42 can number from 2 to 5 or more.
[0020] The motor 44 can be driven by an internal power source 48 , such as a battery or plurality of batteries retained within the housing 20 , or an external source by means of an electrical plug. A satisfactory motor 44 includes a dc motor of approximately 33 watts. However, as discussed below, the specific speed of the motor 44 is at least partly determined by the sizing of the housing 20 inlet and the configuration of the fan blades 42 .
[0021] In one configuration the fan assembly 40 , the housing inlet 22 and housing outlet 24 are selected to provide an air flow of about between 3 and 8 ounces thrust.
[0022] Referring to FIGS. 1 and 2 , the thread capturing device 10 includes a throat 50 proximal to the inlet 22 of the housing 20 , wherein the throat defines a converging section 52 extending from a wide end to a narrow end. The throat 50 can be fixedly or removably attached to the housing 20 . In one configuration the throat 50 converges by between 10% and 70%. That is, the area of narrow end can be approximately 90% to 30% of the area of the wide end.
[0023] The removable grill 60 is disposed within the throat 50 . The grill 60 is removably located relative to the housing 20 , such as by removably connecting the grill to the throat 50 which is affixed to the housing or affixing the grill relative to the throat, wherein the throat is removably attached to the housing. The grill 60 or throat 50 can be removably connected by gravity or a retaining mechanism such as magnets, detents, snap-fit, threads, or hook and loop fasteners. In FIG. 3 , the grill 60 is located at or proximal to the bottom of the throat 50 . Thus, the throat 50 and the grill 60 can be simultaneously removed, cleaned and replaced. However, it is also contemplated the grill 60 can be operably located nearer the inlet of the throat 50 such that the grill (and enmeshed threads) can be removed from the throat, the grill cleaned and replaced.
[0024] The grill 60 includes at least one and more preferably, a plurality of slats or bars 62 extending across the area of the throat. The slats 62 are selected to engage the threads entrained in a passing airflow. Therefore, the slats 62 can have a cross section configured to enhance engagement with the threads. The slats 62 can also have a relatively abrupt edge or leading edge to assist in retention of threads. In one configuration, the grill 60 has a mesh size between approximately 15 mm to 200 mm, such that the threads accumulate on the grill.
[0025] The grill 60 is operably retained within or connected to the throat 50 such that a portion of the grill and slats 62 occlude a portion of the inlet 22 .
[0026] The thread capturing device 10 can include a proximity sensor 70 known in the art, wherein the proximity sensor is configured to detect the presence of a user within a predetermined location of the housing 20 , such as the inlet 22 . The proximity sensor 70 can define a detecting region or volume, wherein the presence of a portion of the user within the zone is sensed and causes activation of the fan assembly 40 . In one configuration, the proximity sensor 70 is selected to detect a user's hand within approximately 6 inches of the inlet. That is, the detecting region has a six inch dimension. Depending on the proximity sensor 70 , the zone sensed by the proximity sensor can be substantially spherical or having generally planar edges. The proximity sensor 70 is operably connected to the fan assembly 40 or the power supply 48 for initiating rotation of the blades 42 .
[0027] It is also contemplated the thread capturing device 10 can include a control switch 74 for selectively disposing the device in an operative state or an inoperative state. The control switch 74 can be connected to at least one of the power source 48 , the motor 44 and the proximity sensor 70 .
[0028] A controller 80 or timer (which can be integral with the controller or separate component 82 , is operably connected to at least one of the fan assembly 40 , the proximity sensor 70 and the power source 48 . The controller 80 or timer 82 is configured to maintain operation of the fan assembly 40 for a fixed period of time from activation, or from the last activation. Satisfactory periods of operation include between approximately 1 to 8 seconds. Thus, the fan assembly 40 terminates operation independent of user intervention.
[0029] In operation, a user having a thread to be captured passes their hand within the detecting region of the proximity sensor 70 . Upon the proximity sensor 70 detecting passage or presence of the hand, the proximity sensor initiates rotation of the fan assembly 40 which creates an airflow across the grill 60 through the inlet 22 of the housing 20 and to the outlet 24 of the housing.
[0030] The airflow is sufficient to entrain an anticipated length of thread such as between approximately one quarter inch to 6 or 12 inches from within the detecting zone of the proximity sensor 70 . The thread is typical sewing thread for residential or even commercial weight, such as fixed length of one inch to 6 inches.
[0031] As the generated airflow passes by the hand of the user (the hand having the thread), the length of thread is entrained within the airflow and removed from the hand. The airflow than passes across the grill 60 and the thread engages portions of the slats 62 and is thus retained by the grill. The controller 80 or timer 82 then terminates operation of the fan assembly 40 after the predetermined time period has elapsed since the last actuation of the proximity sensor 70 or fan assembly.
[0032] Upon collection of a given number of threads on the grill 60 , the user can use a control button 84 to place the thread capturing device in an inoperative state. The control button 84 can be in the form of a shut off, disable or disconnect switch between the power source 48 and the fan assembly 40 . The user can then remove the grill 60 (or the grill and the throat 50 ) along with the captured threads. The captured threads from the removable grill 60 can then be readily disposed as a group into an appropriate disposal mechanism.
[0033] The removable grill 60 (or grill and throat 50 ) is then reengaged with the housing 20 and the control button 84 is actuated to render the capturing device in the operative state and the cycle can repeat.
[0034] Although the present invention has been described in terms of preferred embodiments, it will be understood that variations and modifications may be made without departing from the true spirit and scope thereof. | A system and method for capturing thread from an entraining aft flow is provided, wherein the entraining airflow is selectively created in response to a location of the user relative to the device. The entraining airflow is sufficient to entrain an anticipated length of the thread, wherein the entraining airflow then passes through a grill. The grill shape, the airflow rate and the airflow velocity are selected to retain the entrained thread on the grill. The airflow is then terminated without requiring user intervention. Upon retention of a number of threads on the grill, the grill is separated from the housing and the retained threads are simultaneously disposed of in a desired container. | 3 |
This is a division, of application Ser. No. 146,116, filed May 2, 1980 now abandoned.
FIELD OF THE INVENTION
The present invention relates to insulation of support rails in furnaces with modular refractory fiber insulation modules.
DESCRIPTION OF PRIOR ART
In steel mills, furnaces for steel members such as slabs and the like have been provided with supports or tubes so that the members could be moved through the furnaces and preheated prior to rolling or other treatment. During such movement, the members have usually rested on two types of supports. The first type were generally horizontally arranged sets of tubes of walking beam mechanisms, arranged in rows along the direction of travel through the furnaces. Certain of the sets of tubes moved in a predetermined pattern to move the slab longitudinally through the furnace. The second type of tube supports were stationary rail members along which the steel being preheated was moved by means of some suitable forcing or pushing structure, such as a ram. The temperature of either type of these tubes had to be maintained in a certain specified range to insure that the tubes had sufficient strength to bear the load of the members being preheated. Typically, water or some suitable fluid was pumped through the interior of the tubes to insure sufficient cooling to maintain the specified temperature range. With this technique, however, the fluid drew too much heat from the furnace.
In order to maintain the desired preheating temperature, the furnace was required to be driven to higher temperatures to compensate for heat loss due to the cooling effect of the fluid in the tubes. An undesirable effect of higher temperature in the furnace was the increase of oxidation and slag formation on the members being preheated. Attempts have been made to insulate the tubes with sleeves or coatings of vacuum cast insulation, castable and hard refractory insulation. However, with sleeves of these insulation materials, any pieces of slag falling from the steel members during movement and contacting the insulation readily penetrated the insulation, undesirably reducing the insulative capacity of the sleeves.
U.S. Pat. Nos. 3,952,470 and 4,001,996, of which applicant is inventor, have utilized refractory ceramic fiber modules as insulation for walls of furnaces. The refractory fiber material of these modules has good insulating properties at the temperatures encountered in preheating. However, it was generally considered that this type of fiber material did not lend itself to walking beam tube insulation due to problems with slag penetration of the type encountered with vacuum cast or hard refractory insulation.
SUMMARY OF INVENTION
Briefly, the present invention provides a new and improved insulated support beam, an insulation module for insulating the beam and a method of installing the module. The insulated support beam of the present invention is used for supporting a metal member, such as a steel slab, during movement of the member through a furnace, typically a preheating furnace, and includes a tube member, typically containing flowing water or other fluid, for supporting the member in the furnace. The beam is insulated by an insulating module according to the present invention in the form of a module of refractory fiber blanket material folded into layers extending between end folds and attachment or mounting members inserted in the folds of the module for mounting the module to the tube.
The modules of the present invention are installed by wrapping the blanket material about the tube and attaching the attachment members to the tube. Various attachment structures may be used according to the present invention, and provisions may be made to reduce the possible exposure of the ceramic fiber in the module to slag from the member being preheated. Provision may also be made for additional insulation of the tube.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 and 4 are isometric views of two insulated tube embodiments of the present invention; and
FIGS. 2, 3, 5 and 6 are each vertical sectional view of other insulated tube embodiments of the present invention.
DESCRIPTION OF PREFERRED EMBODIMENT
In the drawings, a support beam S for supporting a metal member, such as a steel slab or rod or beam R, during movement of such member through a furnace such as a preheating furnace is set forth. The support S includes a module M formed from a blanket B of refractory ceramic fiber blanket material. Suitable such materials are, for example, the ceramic fiber blankets sold under the trademarks: "Cera-blanket" of Johns-Manville; "Fiber Frax" of Carborundum Company; and "Kaowool" of Babcox & Wilcox Company. The blanket B is attached or mounted to a tube T of the support S by mounting or attachment members A. Protective shielding material P is also provided to protect the fibers in the blanket B from slag and other particles which may fall from the metal members during movement through the furnace.
Considering the tube T more in detail, such tube is a part of any of several types of conventional walking beam arrangement or stationary support tube arrangement over which the metal slabs or members R move through a preheating furnace or other suitable heating chamber. In either type of support or tube, the tube T includes a generally cylindrical member 10 which is hollow in the interior to contain water or other suitable fluid which flows therethrough from a suitable pumping arrangement in order to cool the tube 10 to a level such that the metal from which it is formed has sufficient strength to withstand the loads of transporting the metal members through the furnace. The tube 10 typically includes a skid rail support member 12 on which the beam R rests when supported by the walking beam member in the furnace. In the past, the tubular members 10 have generally been uninsulated or covered with hard refractory insulation or vacuum cast insulation sleeves.
According to the present invention, the tube T is insulated by the blanket B of the type set forth above. The blanket B is typically in the form of a strip of suitable width, as indicated by an arrow 14, of refractory ceramic fiber blanket. The blanket B is formed into at least two layers beginning at starting end portions 16 and extending along an inner layer 18 to a substantially U-shaped end portions 20 and therefrom along a common, contiguous outer layer 22. A fold 24 is formed along the width of the blanket B between the inner layer 18 and the outer layer 22 within the end portion 20.
If desired, the length of the blanket B between the end portions 20 can be made to substantially exceed the circumference of the tube T, so that when the blanket B is attached or mounted to the tube T, a pocket or pouch is formed beneath the tube T. The pocket may be of any suitable size and may receive refractory fiber insulating material 26 therein depending upon the insulation requirements, or may be a small, unfilled air gap 28 (FIGS. 4-6) to permit thermal expansion differential compsensation. Further, it should be understood that the blanket B may in certain instances be snugly fit to the exterior of the tube T.
A first embodiment (FIG. 1) of the attachment members A includes a support beam in the form of a rod or bar 32, which may be of any of the types set forth in U.S. Pat. Nos. 3,952,470 and 4,001,996 previously discussed of which appliclant is the inventor. One of the bars 32 is mounted in each of the folds 24 and extends a suitable supporting length along at least a portion of the fold 24 within the blanket B with a center portion 34 of the rod 32 positioned approximately at a mid-point along the width of the module M.
An attachment tab 36 is mounted at the center portion 34 of the rod 32 at an inner end. A lug or blade member 40 of the tab 36 pierces the end portion 20 of the blanket B and extends outwardly therefrom and is adapted to be bent or moved into a position contacting the external periphery of the tube T for mounting by some suitable technique, such as welding or bolting by a bolt 41.
Certain tubes T may have mounting rib or rail members 42 (FIGS. 2 and 3) formed on side portions thereof. In these situations, the blade members 38 may be welded to the mounting ribs 42 after being bent to conform thereto after passing through a suitable opening formed in the rib member 42 to an upper surface 42a.
Another embodiment of an attachment members A according to the present invention (FIG. 4) includes support beams 44 extend along the length of the folds 24 and include outer portions 46 extending outwardly from the sides of the blankets B at their side edges 48. Certain portions of the blanket B in FIG. 4 have been removed from the drawing to more clearly show the attachment structure A. Attachment tabs 50 extending parallel to the side surface of the skid rail 12 are formed at outer end portions 46 of the support beam 44. The tabs 50 for attaching the blanket B are attached by a pin or bolt 52 or other suitable fastening means to the skid rails 12. The pin or bolt 52 passes through holes 54 in the attachment tab 50. The holes 54 in the attachment tab 50 are preferably in the form of slots to permit compensation for thermal expansion differential between the tube 10 and the support beams 44.
As has been set forth above, refractory ceramic fiber blanket materials have previously been considered unsatisfactory for use in preheat furnaces due to the lack of resistance to slag and other particles. However, with the present invention, insulating modules M for the support tubes 10 are formed which afford the insulating capabilities of the cermaic fiber blanket materials while protective structure P is provided to prevent substantial damage to the fiber materials from slag from the slabs in the furnaces.
For example, as can be seen in FIG. 1, the attachment tabs A mounting the module M onto the tube 10 are located at positions so that the module M encloses less than the entire circumference of the tube 10, leaving portions of the tube 10 unenclosed or uncovered between the end portions 20 of the blanket B and the skid rail 12. The amount of this uncovered space on the tube 10 may vary according to the desired degree of protection of the blanket B from slag. With the present invention this space is filled with a protective coating in the form of a refractory mortar 56. Usually, at least the end portions 20 of the blanket B are also covered with the mortar 56 for protective purposes. A suitable such mortar is the alumina-chromic oxide, phosphate bonded mortar sold as "Jade Set Super" by A. P. Green Refractories Co. of Mexico, Mo. Such a mortar is applied by a trowel or other suitable technique and thereafter air sets for hardness. Once hardened, a protective insulative coating is formed about the periphery of the tube 10 unenclosed by the blanket B. Where the tube member 10 includes mounting rib members 42 (FIG. 2), the space between the skid rail 12 and the rib members 42 may be filled with the mortar 56. Further, end portions 20 of the blanket B are covered with a layer of the mortar 56 for insulative/protective purposes. If desired (FIG. 3), a layer of ceramic fiber blanket or insulating material 58 may be mounted on the tube 10 between the skid rail 12 and the mounting rib members 42 prior to application of the mortar 56 to increase the insulative capacity of the support S.
In certain other situations (FIG. 4), the protective structure P may take the form of a plate or shield 60 having an inner lip 62 inserted between the skid rail 12 and the end portions 20 of the blanket B. The shield further includes a cover member 64 extending over and covering the blanket B for an extent determined by the desired amount of protection.
A protective plate 66 (FIG. 5) may also be utilized. The plate 66 is mounted to a top portion of the pipe 20 by welding or the like and extends outwardly to lip members 68 which cover the end portions 20 of the blanket B, again with the extent of such coverage being determined by the amount of protection desired. Further, if desired, the space, if any, between the tube 10 and the plate 66 may be filled with ceramic fiber insulating stuffing or strips 70.
Another type of protective structure (FIG. 6) of the present invention is in the form of protective plate member 72 bolted or welded to the tube 10 on each side of the skid rail 12 and extending outwardly to cover the end portions 20 of the blanket B to the desired extent. Refractory ceramic fiber insulating stuffing or strips 74 may be inserted to fill any voids or gaps between the plate 72 and the tube 10. The protective plate 72 may be attached to the tube 10 by bolting or by welding as desired.
In installing insulating modules according to the present invention to form the support S, an initial module M (FIG. 1) is mounted at a suitable starting point on the tube 10 by wrapping the blanket B about the tube 10 and attaching the attachment members A to the external surface of the tube 10. Another module M is then placed abutting the installed module in a similar manner. The installation of the module continues until the tube 10 has received insulating modules M along its entire length. The modules M may be trimmed in width for fitting purposes, if necessary. The mortar 56 may be applied during or after attachment of the modules M to the tube 10.
Installation of the module M of the type shown in FIG. 4 is similar to the foregoing method of installation. Adjacent modules M are positioned on the tube 10 and their attachment tabs 50 moved into alignment so that the pins or bolts 52 may pass through the slotted holes 54. The annular space between adjacent modules M is then filled with a strip of ceramic fiber blanket 74 which may be glued or otherwise fixed into place. Protective coverings of the type shown in FIGS. 4 through 6, inclusive, may also be installed concurrently with or after installation of the modules M.
With the present invention, a substantial problem in the industry has been solved. Further, with the present invention, an unexpected result is obtained. By insulating all of the tube 10 except the skid rail 12, where such a rail is formed on the tube 10, the amount of heat transferred from the furnace to the cooling fluid in the interior of the tube T is reduced due to the insulating effect of the refractory ceramic fiber blanket B. Thus, the cooling fluid in the tube T only has to remove that heat which it receives through the skid rail 12 or the metal protective structure. In this manner, substantially less cooling fluid flow is required. Prior to the present invention, the uninsulated tube T drew substantial heat from the furnace and therefore required that the furnace be driven to higher heat levels in order to provide adequate heat. However, as has been set forth, the higher heat levels to insure adequate heating of the beams or bars only increased the oxidation and slag problem.
The foregoing disclosure and description of the invention are illustrative and explanatory thereof and various changes in the size, shape and materials as well as in the details of the preferred embodiment may be made without departing from the spirit of the invention. | Fluid containing support members of walking beam mechanisms for moving beams and the like in furnaces are insulated with refractory ceramic fiber blanket modules. The modules are wrapped about the support members and attched with attachment members. Protective coverings are provided to reduce exposure of the fiber materials from slag from the beams. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of application Ser. No. 10/860,019, filed Jun. 4, 2004, now allowed, itself a continuation of application Ser. No. 09/898,467, filed on Jul. 5, 2001, now U.S. Pat. No. 6,752,689, which is a continuation of application Ser. No. 09/498,926 filed on Feb. 4, 2000, now U.S. Pat. No. 6,368,181, the disclosures of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to wafer polishing apparatus in general and to measuring systems incorporated into such apparatus in particular.
BACKGROUND OF THE INVENTION
[0003] Wafer polishing systems are known in the art. They polish the top layer of semi-conductor wafers to a desired thickness. To do so, the wafer being polished is immersed in a slurry of water and chemicals during the polishing process. Once the wafer has been polished and washed down, it is placed into an exit station known by some companies as a “water track”, after which the wafer is placed into a cassette of wafers. The cassette is maintained within a water bath until full, after which the entire cassette is brought to a cleaning station to remove any chemicals and slurry particles still remaining on the wafers in the cassette and to dry the wafers. After cleaning, the wafers are brought to a measurement station to determine if the polisher produced the desired thickness of their top layers.
[0004] FIG. 1 , to which reference is now briefly made, illustrates a prior art water track, such as the water track of the #372 Polisher manufactured by IPEC Westech Inc. of Phoenix, Ariz., USA. The water track, labeled 10 , comprises a frame 12 and a base 14 . Frame 12 has jet holes 16 connected to jets (not shown) which emit streams 18 of water through holes 16 . Base 14 has holes 20 connected to bubblers (not shown) which bubble small amounts of water 22 through holes 20 . When a wafer 25 is dropped into water track 10 , pattern-side down, the jets and bubblers are activated. Streams 18 , from the water jets, serve to force the wafer 25 in the direction indicated by arrow 24 . Small streams 22 push the wafer 25 slightly away from the base 14 and ensure that, while the wafer 25 moves through the track, it never rubs against base 14 and thus, the pattern on the wafer is not scratched.
[0005] Other companies produce polishers whose exit stations are formed just of the cassettes. Such a polisher is in the 6DS-SP polisher of R. Howard Strasbaugh Inc. San Luis Obispo, Calif., USA.
SUMMARY OF THE INVENTION
[0006] It is an object of the present invention to provide a measurement system installable within a polishing machine and, more specifically, within the exit station of a polishing machine.
[0007] In accordance with a preferred embodiment of the present invention, the present invention includes an optical system, which views the wafer through a window in the exit station, and a gripping system, which places the wafer in a predetermined viewing location within the exit station while maintaining the patterned surface completely under water. The present invention also includes a pull-down unit for pulling the measurement system slightly below the horizontal prior to the measurement and returns the measuring system to horizontal afterwards.
[0008] In accordance with a first preferred embodiment of the present invention, the gripping system includes a raisable gate which collects the wafer in a predetermined location, and a gripper which grips the wafer, carries it to the viewing location and immerses the wafer, along a small angle to the horizontal, in the water. The gripper also holds the wafer in place during the measurement operation, after which, it releases the wafer and the raisable gate is raised
[0009] The present invention incorporates the method of immersing an object into water such that very few bubbles are produced on the wafer surface. The method of the present invention preferably includes the step of immersing the object while it is held such that its surface plane is at a small angle to the horizontal.
[0010] In a second embodiment, the measurement system includes a water bath and a gripping system thereabove. The gripping system includes wafer holding elements, which receive the wafer, and a gripper whose initial location is above the expected reception location of the wafer. The gripper is flexibly connected at an angle to a piston such that the wafer is immersed in the water at an angle to the horizontal.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The present invention will be understood and appreciated more fully from the following detailed description taken in conjunction with the drawings in which:
[0012] FIG. 1 is a schematic illustration of a prior art water track;
[0013] FIG. 2 is a schematic illustration of a measurement system installable within a polishing machine, the measurement system being constructed and operative in accordance with a preferred embodiment of the present invention;
[0014] FIGS. 3, 4 , 5 , 6 , 7 and 8 are schematic, side view illustrations of a gripping system forming part of the measurement system of FIG. 2 in various stages of operation;
[0015] FIG. 9 is a schematic illustration of an example optical system forming part of the measurement system of the present invention;
[0016] FIG. 10 is a top view of a second embodiment of the measurement system of the present invention; and
[0017] FIGS. 11, 12 and 13 are side views of the measurement system during receipt, transfer and measurement of the wafer, respectively.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Reference is now made to FIG. 2 , which illustrates a measurement unit installable within a polishing machine, such as the IPEC Westech machine, the measurement system being constructed and operative in accordance with a preferred embodiment of the present invention and to FIGS. 3, 4 , 5 , 6 , 7 and 8 which illustrate the operation of a gripping system forming part of the measurement system of FIG. 2 . Similar reference numerals are utilized to refer to elements of the water track previously discussed.
[0019] The measurement system, labeled 30 , comprises an optical system 32 and a gripping system 34 operative in conjunction with a water track 36 . The optical system 32 can be any optical system which measures the thickness of the top layer of the wafer through water. FIG. 9 provides one example of such a optical system; other optical systems are also incorporated into the present invention.
[0020] The gripping system 34 comprises a raisable gate 40 , a translatable gripper 42 , a vacuum pad 44 and a vacuum system 46 . Gate 40 is controlled by a lifting mechanism 48 which raises and lowers gate 40 as necessary. Gate 40 has an upper surface 50 with a curved outer edge 52 and a plurality of protrusions 54 extending downward into the water from the upper surface 50 . Protrusions 54 provide a lower surface onto which the gate 40 is lowered while enabling the water to pass through the gate 40 . Curved edge 52 is shaped to match the curved edge of the wafer 25 so that, when gate 40 is in its lowered position, gate 40 will both keep the wafer 25 from passing out of the water track and to hold the wafer 25 in a repeatable location.
[0021] Gripper 42 translates between the wafer collecting position defined by the curved edge 52 and a wafer measuring location indicated in FIG. 2 by the wafer 25 . Although not visible in FIG. 2 , the base of the water track at the wafer measuring location has been replaced by a window 60 ( FIGS. 3-9 ) to enable the optical system 32 to view the patterned surface 62 of the wafer 25 . For the purposes of the explanation, the patterned surface 62 is shown exaggeratedly in the Figures.
[0022] Gripper 42 can be translated by any translation system; an example of one such system is provided in FIG. 2 and labeled 64 .
[0023] The vacuum pad 44 is typically a bellows-shaped pad and is mounted at the end of the gripper 42 and is connected to the vacuum system 46 . The vacuum pad 44 creates a suction so that gripper 42 can raise the wafer 25 and move it from the wafer collecting position to the wafer measuring location. In addition, the vacuum is maintained during the measurement and only released once the measurement is complete.
[0024] FIGS. 3-8 illustrate the operation of the gripping system 34 . Initially, and as shown in FIG. 3 , the jets, labeled 70 , and the bubblers, labeled 72 , of the water track are operated and the gate 40 is lowered. The polisher (not shown) places the wafer 25 within the water track and the streams 18 from the jets 70 push the wafer 25 towards the gate 40 . The gripper 42 is at the wafer collecting position, shown to the left in FIGS. 3-8 .
[0025] Once the wafer 25 is in the wafer collecting position, as shown in FIG. 4 , gripper 42 lowers vacuum pad 44 to grab the wafer 25 . It will be appreciated that gripper 42 can be formed of any suitable mechanism, such as a piston, which can move vacuum pad 44 up and down on command. Since bubblers 72 are operating, the small streams 22 maintain the wafer 25 away from the base 14 of the water track.
[0026] The gripper 42 then pulls the wafer 25 out of the water ( FIG. 5 ) and the jets 70 are deactivated. In accordance with a preferred embodiment of the present invention, the axis 74 of symmetry of the vacuum pad 44 is formed at a small angle α from the vertical axis 76 . As a result, a long axis 75 of the wafer 25 is at the same small angle α to the horizontal axis 78 . Angle α is typically in the range of 2-5°.
[0027] Translation unit 64 then moves gripper 42 to the wafer measuring position, shown to the right in FIGS. 4-8 . At the same time and as shown in FIG. 6 , a pull-down mechanism slightly lowers the entire water track, gripping and optical system unit (at an angle of 1-3°), about a hinge 80 ( FIGS. 2-8 ), to force the water toward the wafer measuring position. Other methods of forcing the water towards the measuring position are also incorporated in the present invention.
[0028] After the lowering of the water track, gripper 42 lowers the wafer 25 towards the window 60 . Since the vacuum pad 44 is angled, the wafer 25 does not enter the water all at once. Instead, wafer 25 enters the water gradually. Initially, only the side labeled 82 is immersed. As the gripper 42 pushes the vacuum pad 44 further down, more and more of the wafer 25 becomes immersed until the entire wafer 25 is within the water. Vacuum pad 44 is flexible enough to accommodate the changed angle of wafer 25 .
[0029] It will be appreciated that, by gradually immersing the wafer in the water, few, if any, bubbles are created near the patterned surface of the wafer 25 .
[0030] It is noted that the wafer 25 does not rest against the window 60 . Instead, it is held against protruding surfaces 84 such that there is a layer of water 86 between the wafer 25 and window 60 . Due to the gradual immersion of wafer 25 , layer 86 of water has little, if any, bubbles in it and therefore provides a uniform connecting medium between the optical system 32 and the patterned surface 62 of wafer 25 .
[0031] Once the optical system 32 has finished measuring the patterned surface 62 of wafer 25 , gripper 42 returns vacuum pad 44 , with wafer 25 still attached, to its upper position. The pull-down mechanism rotates the water track about hinge 80 to return to its original position, gate 40 is raised, and jets 70 and bubblers 72 are activated. The vacuum system 46 releases the vacuum and the wafer 25 falls into the water track. The flow of water causes the wafer 25 to move toward and under the now raised gate 40 . A sensor 90 determines when the wafer 25 successfully passes out of the water track. The process described hereinabove can now begin for the next wafer.
[0032] Reference is now made to FIG. 9 which schematically illustrates an example of a suitable optical system 32 . Optical system 32 is a microscope-based spectrophotometer and comprises an objective lens 100 , a focusing lens 102 , a beam splitter 104 , a pin hole mirror 106 , a relay lens 108 and a spectrophotometer 110 . It additionally comprises a light source 112 , a condenser 114 , a charge coupled device (CCD) camera 116 and a second relay lens 118 .
[0033] Light from light source 112 is provided, along an optical fiber 113 , to condenser 114 . In turn, condenser 114 directs the light towards beam splitter 104 . Beam splitter 104 directs the light towards the wafer surface via lenses 102 and 100 and via window 60 and water layer 86 .
[0034] The reflected light from the patterned surface 62 is collected by objective 100 and focused, by lens 102 , onto pin hole mirror 106 . Relay lens 108 receives the light passed through pin hole mirror 106 and focuses it onto the spectrophotometer 110 .
[0035] Pin hole mirror 106 passes light through its hole towards spectrophotometer 110 and directs the light hitting the mirror surface towards CCD camera 116 . Second relay lens 118 receives the light reflected by pin hole mirror 106 and focuses it onto the CCD camera 116 .
[0036] Since the pinhole is placed at the center of the image plane which is the focal plane of lens 102 , it acts as an aperture stop, allowing only the collimated portion of the light beam to pass through. Thus, the pinhole drastically reduces any scattered light in the system. Relay lens 108 collects the light from the pinhole and provides it to spectrophotometer 110 .
[0037] Furthermore, since the pinhole is located at the image plane of the optical imaging system (lenses 100 and 102 ), only that portion of the light, reflected from the surface of wafer 25 , which is the size of the pinhole divided by the magnification will come through the pinhole. Relay lens 118 collects the light and focuses it onto the CCD camera 116 .
[0038] The pinhole serves to locate the measurement spot in the image of the wafer 25 . Since the pinhole allows light to pass through it, rather than being reflected toward the CCD camera 116 , the pinhole appears as a sharp dark point in the image produced by the lens 118 . Thus, when viewing the CCD image, the location of the measurement spot is immediately known, it being the location of the dark spot.
[0039] Reference is now made to FIGS. 10-13 which illustrate the thickness measuring of the present invention implemented in a polishing machine similar to that produced by Strasbaugh which has no water track. In this embodiment, the polishing machine or an external robot (not shown) brings the wafers 25 to an exit station of the polisher. When the measurement has finished, the robot brings the wafers 25 to their cassette at another exit station. FIG. 10 is a top view and FIGS. 11, 12 and 13 illustrate the measuring station in three states.
[0040] The measuring station 130 comprises a gripping unit 132 , an optical system 134 and a water bath 136 . The optical system 134 is located beneath the water bath 136 and can be any suitable optical system, such as the one described hereinabove. As in the previous embodiment, the water bath 136 has a window in its bottom surface, labeled 140 in FIG. 11 , through which the optical system 134 can illuminate the wafer 25 .
[0041] The gripping unit 132 comprises a wafer support 150 , illustrated as being formed of two support elements, a vacuum pad 152 , similar to vacuum pad 44 , and a piston 160 . The polisher places the wafer 25 on the wafer support 150 while the vacuum pad 152 is initially in a position above the support 150 , as shown in FIG. 11 . Once the wafer support 150 has the wafer in a predefined position, the vacuum pad 152 , which is controlled by piston 160 , moves toward the wafer and grabs it by applying a vacuum. Now that the vacuum pad 152 is holding the wafer, the wafer supports 150 move away, as indicated.
[0042] The piston 160 then pushes the vacuum pad-wafer combination toward the water bath 136 . This is shown in FIG. 12 which also illustrates that the vacuum pad 152 holds the wafer 25 at a small angle α to the horizontal. The angle a is provided since, as in the previous embodiment, the axis of symmetry of the vacuum pad 152 is formed at a small angle α from the vertical axis. As in the previous embodiment, by immersing the wafer 25 into the water at the angle α, few, if any, bubbles, remain on the undersurface of the wafer after full immersion.
[0043] FIG. 13 illustrates the wafer 25 at its fully immersed, measurement position. Typically, wafer 25 does not directly touch the water surface 163 of the window 140 ; instead, it sits on a measurement support 168 . The result is that there is a water layer 164 between the wafer 25 and the surface 163 of the window.
[0044] Once the measurement process has finished, the piston 160 returns the wafer 25 to its original position and the wafer support elements 150 return to their wafer receiving position. The piston 160 places the wafer 25 on the wafer support elements 150 and releases the vacuum. The external robot can now take the wafer to another exit station where there is a cassette of processed and measured wafers.
[0045] It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather the scope of the present invention is defined by the claims which follow: | The present invention is aimed to provide a measurement system installable within a processing equipment and more specifically within the exit station of a polishing machine. The optical scheme of this system includes a spectrophotometric channel, an imaging channel and also means for holding the wafer under measurement. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to an electrical contact switch intended to be mounted, in particular, on a printed circuit board.
There are numerous applications for which industry seeks switches which combine reliability and constant switching force over a long life in a design that is simple, economical, and of small size.
Moreover, for certain applications it is necessary for the upper face of the switches to be illuminated internally. Mounting the switches in position must also be simple.
It is also desirable to have a modular switch which can easily be mounted on a previously prepared printed circuit board and whose structure is such that the function of the external housing of the switch is reduced merely to the function of masking and not the function of guiding.
There is known a push-button switch having a resilient element of rapid action, which is described in French Patent No. 2,468,197, which partially fulfills the above-mentioned conditions. Such a switch has a particularly long, useful life due to a special arrangement and to the use of a helical spring arranged transversely to the direction of movement of the push-button.
Although such prior switch has certain advantages, it also has disadvantages. There is no provision for illumination of the front face of the push-button. The switch has a pusher that is guided by the cover of the casing and by a fork in its lower part. The forces exerted on the push-button, when they are not precisely on the axis of the pusher, can bring about premature wear of the guiding means. Premature wear of the guiding means may lead to the introduction of foreign material inside the casing in the form of dust, which can lead to poor functioning of the switch.
A principal object of the present invention is to provide an electrical contact switch intended to be mounted on a printed circuit board, which overcomes disadvantages of the known switches.
SUMMARY OF THE INVENTION
According to the invention, there is provided an electrical switch comprising a base provided with electrical contacts, a cover which is movable with respect to the base and has means for illumination, electrical connections for the illumination means, and at least one arched resilient element arranged substantially transversely to the direction of movement of the cover and cooperating with the cover. A shoe which is joined to the cover cooperates with a means for guiding and for limiting the movement of the shoe relative to the base. The shoe is provided with electrical contacts arranged opposite the electrical contacts on the base along the direction of movement of the cover.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view of a switch according to the invention, with part of the switch cover removed;
FIG. 2 is a sectional view of the switch shown in FIG. 1 taken along a longitudinal vertical central plane; and
FIG. 3 shows, on the right-hand side, a sectional view along a transversal central plane and, on the left-hand side, an elevation with some parts removed.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows the three principal subassemblies of the switch 8 according to the invention, namely, a base 10, a cover 12, and a shoe 14, each of which is preferably formed of plastic.
The base 10, which is of substantially rectangular shape, has two springs 16 of the helical type which are arched upwards. The ends of the springs are received in seatings 18 inclined with respect to the horizontal plane of the base so as to orient the arching of the spring upwards. The base also has four electrical contacts or fixed blocks 20 situated on opposite sides of a longitudinal groove 22. The contacts 20 extend below the base 10 to form pins 24.
A complementary groove 26 is formed in the base which is perpendicular to the first groove 22. The longitudinal side walls 27 of the base each have a recess 28, substantially in the center of which there projects a retaining stop 30. The stop is molded in one piece with the base. The transverse side faces 31 of the base also have recesses 32 through which pass the helical springs 16. Hence the springs are accessible from above the base. The base 10 is provided with four vertical bores 34, through which pass electrical supply connection 36. The upper end of each connection 36 is in the form of a noncontiguous helical spiral 38, while the lower part 40 is bent into a J shape in order to form a pin. An annular groove 42 is formed in the upper cylindrical part 44 of the base.
The shoe 14 has a U shape. The lower or open side of the shoe is oriented opposite the base 10, and it has in its center, parallel to its arm 45, a rib 46 of a height greater than that of the arms, thus separating the lower side of the shoe into two seatings or recesses 48. Leaf springs 50 of a C-shaped profile are mounted in the seatings 48, although one spring is shown below the seating in FIG. 1. The central parts 52 of the springs are introduced with slight force into the seatings 48, in which they are frictionally held, while the curved ends 54 extend laterally beyond the seatings 48. Each spring comprises a leaf. Notches 56 are made in the curved ends 54 of these springs so as to form a double contact. The shoe also has two lateral lugs 58 on the outside of the arms 45 and a pivot pin 60 which projects upwardly from the shoe.
The cover 12 which serves as a push button is of rectangular shape, and its dimensions are such that its side walls are disposed outside the base 10 and are slidable with respect to the base.
As seen in FIG. 1, the cover has an opening 62 near the middle of one of its side walls. The cover 12 also has an interior support plate 64 which receives a printed circuit board 66 on which are arranged light-emitting diodes 68. The diodes are arranged in two parallel series along the longitudinal axis of the board 66. The board 66 is provided with holes 70 through which the upper ends of the supply connections 36 extend.
The cover has an interior ledge 72 above the plate 64. A transparent or at least translucent mask 74 is mounted on the ledge. The mask carries a pictogram 76 of the function which can be executed by means of the switch according to the invention.
In FIG. 1, there is also shown a sealing membrane 78 located between the shoe 14 and the support plate 64 which is connected to the cover 12. The diameter of the membrane is sufficient to cover the upperr cylindrical part of the base 10. The membrane has an inwardly extending annular flange 80 mounted in the groove 42. In its upper part, the membrane 78 has a bore 82 through which the pivot pin 60 extends.
With reference to FIG. 2, a hollow female part or socket 84 is formed on the bottom of support plate 64 which cooperates with the head 61 of the pivot pin 60. This results in the shoe 14 being loosely mounted on the push button or cover, in that the pin head 61 can pivot to allow the bottom of the shoe and the contacts 50 to shift position horizontally with respect to the push button. FIG. 2 also shows a printed circuit board 86 intended to receive the switch according to the invention. The switch is fastened to the board by soldering the pins 24 to the board. The lower ends 40 of the supply connections 36 are also soldered to the board 86 so as to enable electric current to pass into the diode support plate 66. The upper ends of the connections 36 are soldered at 88 to the same plate. FIG. 2 also shows the external covering 90 of the apparatus in which the modular switch according to the invention is arranged.
As seen in FIG. 2, lugs 92 are formed on the inside of the cover side walls. The lugs lie in the recesses 32 and bear against the middle of the arched springs 16.
The assembly of the switch according to the invention is effected in the following way. The printed circuit board 66 provided with the diodes 68 and connections or springs 36 are mounted on the support plate 64. The supply connections 36 are then fastened by soldering at their upper ends to the board 66. The contacts 50 are slid into the seatings 48 of the shoe 14 until they latch in. Similarly, the mask 74 is fastened to the upper part of the cover 12. The base 10 is provided with its helical springs 16 and receives in its grooves 22 and 26 the rib 46 and the lugs 58 of the shoe 14, respectively. The head 61 of the pin 60 is passed through the bore 82 in the sealing membrane 78, and the flange 80 of the membrane 78 is positioned in the groove 42 in the upper part 44 of the base 10. The base 10 is then introduced into the cover 12 until the head 61 of the pivot pin is pressed into the socket 84 by deflection of resilient material of the socket until the head latches in.
The lower ends or pins 40 of the connection devices 36 are passed through the bores 34 in the base 10 and project out of the lower part of the base.
The assembly of the switch according to the invention on the printed circuit board 86 is effected in a simple manner by inserting the pins 24 and 40 into the board 86 and by fastening the latter, for example, by welding spots or soldering.
The operation of this switch is reliable and simple, as will be described below.
The user exerts a pressure on the upper face of the switch 8 and, more particularly, on the mask 74, which moves down the cover 12 with respect to the base 10. The cover 12 drives down the shoe 14 which is joined to the cover 12. The lugs 92 on the cover 12 bear against the springs 16. The user must therefore overcome the resistant force of the springs 16 which, in the example shown, is of the order of 250 gM per spring. Each supply connection 36 has negligible resistance to compression, as compared to that of the helical springs 16 and thus the connections 36 do not appreciably affect depression of the cover. The rib 46 and the lugs 58 slide respectively in the grooves 22 and 26. As can be seen in FIG. 2, the distance "h" separating the lower part of the rib 46 from the bottom 94 of the groove 22 is slightly greater than the distance "d" which separates the lower part of the curved parts 54 of the spring leaves 52. When the spring leaves 52 press firmly on the contacts 20, the bottom of the rib 46 abuts the bottom 94 of groove 22, thus avoiding plastic deformation of the leaves 52.
When the rib 46 abuts the bottom of the groove 22, the helical springs 16 are resiliently deflected into a substantially M-shaped profile. As soon as the user releases the pressure exerted on the cover 12 via the mask 74, the springs tend to reassume their initial arch and thus repel the cover 12 upwards. This lifts the shoe 14 and the contacts 50 thereon to separate the contacts 50 and 20. The curved parts 54 of the spring leaves thus reassume their initial profile because of the inherent resilience of the material of which they are made.
The cover 12 pushed by the spring 16 moves away from the base 10 until the retaining stop 30 comes into contact with the lower edge of the opening 62 made in the cover 12, thus preventing the cover 12 and the base 10 from becoming separated.
In this position, the lower end of the rib 46 on the shoe is always in contact with the groove 22 and the rib remains guided, while the side walls of the cover 12 also surround the base 10 at one part of its height.
The switch according to the invention thus has numerous advantages, in particular close guiding of cover 12 in sliding with respect to the base 10. The shoe 14 which holds the contacts 50 is independently guided in sliding movement, so manufacturing tolerances do not add to cause misalignment of the contacts 50, 20. Because of the helical shape of the supply connections, they can undergo a great many cycles, bringing about a very long life for the switch.
The light-emitting diodes 68 enable illumination of one row or the other, or of both together, as desired. This illumination is effected with limited emission of heat.
Furthermore, the membrane 78 ensures complete sealing during the movement of the shoe 14 in the base 10, thus avoiding any penetration of water, dust, or any other element which might impair the good functioning of the electrical contacts. The electrical contacts must be kept clean and water must not accumulate in the upper part of the base 10 so that the circuit-breaking ability of the switch is maintained.
Such a sealing membrane has an important function in particular in the case where this switch is used in atmospheres or in applications such as aviation where the reliability requirements are high.
It is seen that the assembly of this switch is effected in a simple manner. The cover 12 is joined by means of the pivot pin 60 and latched onto the retaining stops 30 of the base 10.
The switch according to the invention consists of a single module which, once assembled, can be easily installed on printed circuit boards such as 86.
The switch according to the invention does not require further adjustment with respect to the covering 90, since movement of the switch parts is independent of the latter. This ease of assembly brings about a very low cost for the assembled switch.
The embodiment which has just been described has two contacts 50, four fixed block contacts 20, and two rows of light-emitting diodes 68. This double input/double output switch can be used to act in a single circuit or in two independent circuits, which correspondingly increases its versatility of use.
Although several embodiments of the invention have been disclosed herein for purposes of illustration, it will be understood that various changes can be made in the form, details, arrangement and proportions of the various parts in such embodiments without departing from the spirit and scope of the invention as defined by the appended claims. | An electrical contact switch for mounting on a printed circuit board, having a base provided with contacts, an illuminated cover movable with respect to the base and arched coil springs on the base arranged transversely to the direction of movement of the cover which resist downward movement of the cover. A shoe joined to the cover is guided for limited movement toward the base and is provided with contacts that engage the contacts on the base. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method and apparatus for quoting, administering, maintaining, claim processing, and renewing life, health and related coverages for clients, especially group clients. Significantly, the method may be employed so that information regarding any aspect of the insurance transaction need only be entered once, minimizing the risk of error and providing additional security for the information. The method also supports a Management Information System tool for providing timely and accurate information on quotes, sales, claim status, and client administration.
2. Description of the Prior Art
Insurance administration benefits from computerized processing by minimizing the risks of lost and mishandled information as well as reducing the cost of doing business. Because of the multiple combinations of insurance products available, it is very important to prepare accurate proposals and illustrations of insurance products for each prospective client. Computerized processing is of assistance in this area as well.
In most insurance companies, requests for insurance quotes are typically processed on paper through a sales office and then sent to a corporate office for additional processing. The processing of these papers results in time delays, multiple requests for information, and the increased risk of error in collecting or processing information.
Previous processes have been produced to provide proposals in a group insurance setting. These products were inefficient, restrictive and time consuming for the users. Among the problems with previous quoting programs were the lack of comprehensive coverage databases and the inability to transfer information amongst the several departments within the insurance company.
Group insurance products generally have a renewal cycle of one to three years. As a result of this cycle, the need to provide not only temporal information about a group insurance transaction, but also information that spans a time interval, is critical. The paper-based processing of this information is cumbersome and expensive.
SUMMARY OF THE INVENTION
This system uses thin client architecture to improve the speed and accuracy of the entire insurance operation. To overcome the complexity of the calculation in a requested quote and to speed up the operation of presenting a proposal, the processes are divided into server and client processes. Quote information is entered at the client level and complex calculations to generate the quote are performed at the server through a Wide Area Network (“WAN”). This configuration results in the ability to produce on-line quotes using rule based quoting logic and completing the process in seconds. This system also eliminates the need for human interaction beyond the collection of information by the sales representative.
The present invention is a method and apparatus for automatically quoting, processing, maintaining, claim processing, and renewing life, health and related coverages. It comprises an integrated computer system containing several processing modules. The processing module into which data concerning the group is initially entered is the quoting engine (“QE”) module. The QE module includes a process for maintaining and describing the coverages available to the group. The QE module also contains processes for rating the insurance and generating a proposal for the client.
Another processing module within the system is a Soldcase module. The soldcase module administers sales and commission data and provides information regarding the selected coverage to other modules within the system.
Another module within the system is an Advanced Relational Database Information System (“ARDIS”) module. The ARDIS module processes billing, premium processing, administering of payment of commissions and other general administrative functions.
A Document Generator module is another module within the system, which is employed to produce documents such as policies and certificates in compliance with state and federal laws. A Claims module adjudicates new claims, maintains claim histories, and issues funds to designated recipients.
The final module within the system is the Renewal module. The Renewal module monitors and updates information regarding the client and the insurance to determine if renewed coverage should be sold to the client and, if so, at what price. The introduction of a Renewal module within the general administrative computer system represents a significant improvement over prior art insurance methods. The Renewal module greatly reduces the amount of time necessary to generate a renewal quote and through automation, greatly decreases the number of manually generated renewals.
The described method is capable of providing not only temporal information regarding a transaction, but also information that spans the life of the insurance product through the employment of a relational database to handle large amounts of data over the contract term. This feature of the invention is especially useful in instances where the client is a group. Furthermore, each module within the method fully communicates with each other module. Accordingly, information entered into a module is utilized throughout the transaction within the insurance company. Since information must only be entered once, fewer insurance company representatives need come in contact with the information, providing greater security for the information.
It is, therefore, an object of this invention to provide a method and apparatus for quoting, issuing, claims processing, and administering insurance coverage that minimizes the amount of information that must be gathered by individuals to administer insurance.
It is a further object of this invention to provide a method and apparatus for quoting, issuing, claims processing, and administering insurance coverage that minimizes the duplication of manually entered information.
It is yet another object of this invention to provide a method and apparatus for quoting, issuing, claims processing, and administering insurance coverage that monitors client information over the life of the coverage and automatically produces information pertaining to the renewal of the policy.
It is a further object of the invention to provide a method and apparatus for quoting, issuing, claims processing, and administering insurance coverage that improves the speed and accuracy of the insurance operation and increases the overall quality of the products purchased by the insurance consumer.
It is another object of this invention to provide a method and apparatus for quoting, issuing, claims processing, and administering insurance coverage that minimizes the number of employees that have access to client information, increasing the level of security for that information.
These and other objects of the invention will be apparent to those skilled in the art.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram that shows the flow of information through the claimed method and the output generated thereby;
FIGS. 2A and 2B represent a flowchart of the Request for Quote process within the Quoting Engine (“QE”) module;
FIGS. 3A and 3B are a flowchart of the coverage process within the QE module;
FIG. 4 is a flowchart of the rating calculation process within the QE module;
FIG. 5 is a flowchart of the proposal process within the QE module;
FIGS. 6A and 6B are a flowchart of the Soldcase process within the Soldcase module;
FIG. 7 is a flowchart of the billing process within the ARDIS module;
FIG. 8 is a flowchart of the premium process within the ARDIS module;
FIGS. 9A and 9B are a flowchart of the commission process within the ARDIS module;
FIG. 10 is a flowchart of the document generation process within the Document Generator module;
FIG. 11 is a flowchart of the claims process within the Claims module;
FIG. 12 is a flowchart of the renewal download process within the Renewal module;
FIGS. 13A and 13B are a flowchart of the renewal process within the Renewal module; and
FIG. 14 is a schematic of the hardware constituting the apparatus of the invention and employed in the method of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The flow of information through the method of quoting, issuing, claims processing, and administering insurance coverage 10 of the present invention is shown in FIG. 1 . It indicates that between the collection of data and the creation of documents representing the transaction, data is processed in some combination of six different modules; a Quoting Engine (“QE”) module 100 , a Soldcase module 200 , an Advanced Relational Database Information System (“ARDIS”) module 300 , a Document Generator module 400 , a Claims module 500 , and a Renewal module 600 . The names given the modules and the accompanying steps performed by the modules are not intended to be rigidly applied, but are intended only to provide an example of the claimed method. Variations on the organization of the method 10 are anticipated and intended to be claimed herein.
The method 10 is to be employed by an insurance company 2 , also referred to as the user. As shown in FIG. 1 , the broker 12 contacts the prospective client 14 , usually a group, to obtain relevant information. Although the method 10 may be employed for individual insurance administration, it is described generally herein as a method for administering group insurance. Once the necessary information is entered into the QE module 100 , the QE module 100 then generates the premium rate and an appropriate proposal 18 is sent to the prospective client 14 .
Once the client 14 accepts the proposal 18 , the sales representative 16 , who may be any employee of the insurance company 2 , enters additional information about the transaction, such as commission, producer and binder amount information, into the Soldcase module 200 . The Soldcase module 200 retrieves all the relevant information from the QE module 100 along with additional information provided by the sales representative 16 to generate a sales entry and assigns a policy number to the transaction. This policy number is subsequently transferred to the ARDIS module 300 , which includes a database. The Soldcase module 200 also generates the approval letter 20 , if the client 14 has requested a letter. The Soldcase module 200 then transfers client information, coverage information, sold rate, sold premium and binder amount in addition to the policy information to the ARDIS module 300 .
Once the product has been sold to the client 14 , the ARDIS module 300 then retrieves the relevant information and creates necessary entries into the database to administer the client's account. The ARDIS module 300 is used to maintain the information throughout the life of the product and to provide certificate, commission, premium and member information to the Document Generator module 400 , lockbox, account department and various subsystems, respectively. The Document Generator module 400 retrieves all of the necessary information from the ARDIS module 300 databases, generates contracts and certificates 28 , and maintains an electronic copy of those documents.
The Claim module 500 receives information from the ARDIS module 300 once the case is issued. The information is passed from the ARDIS tables to the various claim tables through a middleware interface that synchronizes the data. The Claims module 500 adjudicates new claims, maintains claim histories, and issues funds to designated recipients
The Renewal module 600 retrieves the policy data from the ARDIS module 300 databases for a client 14 whose policy is scheduled to expire in the near future. This information is sent to the renewal underwriting department 30 for further renewal processing and, at the same time, may create a renewal letter (not shown) for the client 14 . Based on the information collected by the underwriting department 30 , the QE module 100 generates the renewal premium rate, which is then fed back to the Renewal module 600 and ARDIS module 300 databases. The Renewal module 600 retrieves the necessary information from the ARDIS module 300 and QE module 100 databases to provide the renewal proposal 32 . This information could include revised census details used to generate the revised renewal rate. Once the client 14 renews the product, the renewal module 600 updates the necessary information in the ARDIS module 300 database for continued administration, including updated premium billing rates and commission adjustments. The Renewal module 600 also generates the renewal letter (not shown) that is sent to the client 14 ; the Document Generator module 400 again will maintain the electronic copy of the renewed contract.
The flow of information through the method 10 is shown in more detail in FIGS. 2–12 . The initial steps in the method 10 include the processing of information in the QE module 100 . Among the steps taken in the QE module 100 are the Request For Quote (“RFQ”) process 102 , the coverage maintenance process 130 , the rating process 150 and the proposal process 179 . The initial information may be gathered in any form, such as paper, e-mail, facsimile or other medium as requested by the client 14 .
FIGS. 2A and 2B depict the steps required by the RFQ process 102 within the QE module 100 . This portion of the QE module 100 accepts employer information 106 , including employer identification and industry information, from the client 14 or sales representative 16 and validates the employer information 106 . If the employer identification in the employer information 106 duplicates employer identification in an employer database 304 , then the RFQ process 102 displays a message asking the user to assign a different employer identification. After validating the employer information 106 , the RFQ process 102 of the QE module 100 accepts the Standard Industrial Classification code (“SIC code”) 108 , which is then validated in step 109 against a SIC database 306 . If the SIC code 108 is not available in the SIC database 306 , then it asks the user to enter a valid SIC code 108 for the employer's industry.
Throughout this description of the method 10 , reference is made to several databases. In practice, each database may be a section of a larger database and information stored in a general database may be stored in an individual accessible database.
After validating the SIC code 108 , the RFQ process 102 accepts the quote information 110 and stores it in a general database 310 (not shown) of the ARDIS module 300 . The quote information 110 includes group information, group industry code, quote-effective date, estimated proposed lives, prior carrier, and other standard industry information. The RFQ process 102 then accepts distributor information 112 . In step 114 , the RFQ process 102 validates distributor information 112 with the distributor database 308 and retrieves information regarding the region information 116 , sales information 120 and marketing information 124 from the general database 310 or the sales representative 16 . The information is validated in steps 118 , 122 and 126 , and the information regarding the parties to whom the proposal is to be distributed is entered in step 128 . The QE module 100 stores the entered information (i.e. the entered information regarding the parties to whom the proposal is to be distributed) into the quote database 302 and the employer database 304 .
FIGS. 3A and 3B illustrate the detail data flow of an example of the coverage maintenance process 130 for the QE module 100 . The method 10 may be used for a variety of different coverages, and the examples given are not intended to show the scope of the utility of the method 10 , but are only exemplary. The coverage maintenance process 130 accepts coverage information 132 and plan information 134 from the sales representative 16 and prompts the user determines if the entered coverage is ‘LIFE’; if so, the program logic then allows the user to enter the dependents information 136 . The coverage maintenance process 130 determines if the entered coverage is ‘DENTAL’ or ‘Voluntary DENTAL’ in step 138 ; and, if so, in step 139 , it then checks whether the census has been entered. If the census has not been entered, the process 130 allows the user to enter the census summary 140 . Once the plan information 134 has been entered, then it allows the user to enter class information 142 . For ‘LIFE’ and ‘Voluntary LIFE’ coverages, as determined in step 143 , the coverage maintenance process 130 allows the user to alter coverage amounts 144 . Once the coverage information 132 , plan information 134 and class information 142 have been entered and validated, the coverage maintenance process 130 stores all the data in the coverage, rating and benefit tables of the general database 310 .
If the entered coverage is Long Term Disability (“LTD”) as determined in step 147 , the coverage maintenance process 130 checks whether there is an associated record needed for Long Term Disability Cost Containment (“LTDCC”) or not depending on the entered values in step 148 . If such a record is needed, the coverage maintenance process 130 automatically creates the record 150 . If the entered coverage is ‘DENTAL’ as determined in step 151 , the coverage maintenance process 130 then checks for the plan type in step 152 . If the plan type is PPO and is quoted for multi-area as determined in step 153 , then a second record for the indemnity option 154 is automatically created. This information is then validated.
After validation is complete, the coverage maintenance process 130 checks the underwriting guidelines and determines the quote type for the information that has been entered in step 156 . Typical types of quotes might be “Super Express” (SE), Custom (CU) or Decline (DE). The SE and DE quote types are completely automated within the system, automatically generating in seconds a proposal 18 or a letter declining coverage (not shown), respectively. If the quote type is determined to be CU, the information is further analyzed to determine whether a proposal 18 or letter declining coverage will be sent to the client 14 . Among the considerations employed in determining the quote type are custom business rules and other information supplied by the underwriting department 30 , actuarial department (not shown) and compliance department (not shown).
FIG. 4 is a flowchart of the rating process 160 within the QE module 100 . Once the user selects a quote sequence 162 , the rating process 160 displays all the non-rated options under that quote in step 163 . It allows the user to select multiple options 164 at the same time. It loops through all the selected options beginning with step 165 . If the rating is successful as determined in step 166 , then it determines the quote type for that option in step 168 . If the quote type changes to CU, as determined in step 169 , all the rules for that quote type are displayed in step 170 . The process 160 allows the underwriting department 30 to change some of the values and recalculates the quoted rates. After calculating and entering the premium rates in step 172 , the rating process 160 allows the user to print the rating worksheet 174 , ending the loop for that option in step 176 . If, for some reason, the calculation fails, then it displays a message in step 178 so the sales representative 16 or other insurance company representative can change the information accordingly and re-rate the option. Once the option has been rated, the process 10 does not allow any changes to the quoted information.
FIG. 5 is a flowchart of the proposal process 179 within the QE module 100 . Once a user selects a quote sequence 162 , the proposal process 179 displays all the rated options as well as the decline options under that quote in step 180 . It allows the user to select multiple options at the same time in step 181 and loops through each option starting in step 182 . If the proposal process 179 declines an option in step 187 , a letter 26 notifying the client 14 of the denial is generated. The proposal process 179 determines the type of coverage, eg. DENTAL, in steps 183 and 184 and asks for additional information for those coverages in steps 185 and 186 . If an appropriate proposal 18 is generated in step 188 and validated in step 189 , then the proposal 18 is transmitted to the broker 12 and the client 14 by mail, fax, e-mail, or other medium. As with all input information, all output of the method 10 may be in any form as requested by the client 14 . If, for some reason, the proposal process 179 does not generate a proposal 18 , then it displays a proper message in step 190 so the sales representative 16 can change the information accordingly and re-generate the proposal 18 . Following the generation of the proposal 18 or display of the message 190 , the loop ends in step 192 .
FIGS. 6A and 6B are a flowchart of the Soldcase module process 202 . Once a user selects employer information 106 , the soldcase process 202 displays all the proposed options for that client 14 in step 204 . The user then selects the appropriate option in step 207 and verifies the checklist in step 209 . Once the information is validated, the soldcase process 202 stores all the data in the appropriate database tables and updates the soldcase status to ‘work in progress’ at step 212 .
The process 202 then loops through all the coverages associated with the selected option beginning at step 214 . It may ask for additional information for each of the coverages in step 216 . It may also ask for the commission and producer details in step 218 , storing this information during step 219 into the appropriate database tables in the general database 310 . After validating the data, the soldcase process 202 checks whether the user wants to approve the coverage in step 221 allowing the user to approve the coverage in step 222 , ending the loop at step 223 . If the coverages are not approved as determined in step 225 , the system displays an appropriate message at step 224 . If all the coverages are approved for that group, the process 202 allows the user to submit or approve the checklist at step 226 and updates the status of the policy to ‘approved’ in step 228 . After approval, the user can enter the policy information 230 , store the policy data in step 232 , and transfer this information to the ARDIS module 300 in step 234 . The soldcase process 202 also determines whether an approval letter has been requested in step 235 and generates the approval letter 20 , if it has been requested. The policy data is then stored in the general database tables 310 in the ARDIS module 300 in step 236 .
FIG. 7 is a flowchart of the billing process 312 within the ARDIS module 300 . The billing process 312 supports manual as well as automatic billing. A user can request a specific bill at step 313 and provide a manual billing request 314 ; otherwise, automatic billing is designed to occur on all the bills that are due based on their billing periods such as on the 10 th or 20 th day of the month as determined in steps 315 and 316 . The automatic billing generates a bill request in step 318 that is similar to the manual billing request entered in step 314 .
The billing process 312 determines whether the request is to draw the bill 319 or to reprint the bill in step 320 . If the request is to draw a bill, the billing process 312 in step 321 seeks the bill in the billing table of the general database 310 . If it finds a bill, the past term bill is deleted from the billing table in step 322 and a new billing record is created in the billing table in step 324 to replace the existing past term bill. If no past term bill exists, the billing process 312 creates a new record in the billing table in step 324 . It uses employer information, coverage information, rate information, enrollment information and premium information from the general database 310 to generate a billing record. After creating the record in the table, it generates a bill in step 326 by accessing the billing data 327 . If the bill is a virtual bill as determined in step 328 , the billing process 312 rolls back all the database changes in step 330 and stores the billing information in the archived database in step 332 . If the request is made to reprint the bill in step 333 , then it generates a bill 336 based on current bill information. If the request is made for a specimen bill in step 334 , the process only displays the bill on the screen in step 335 .
FIG. 8 is a flowchart of the premium process 338 within the ARDIS module 300 . This process supports manual premium processing as well as automatic premium processing and determines which method is to be applied in steps 339 and 340 . In manual processing, a user can enter the payment manually in step 341 when the payment is received from the customer at 342 . In the automatic process, the ARDIS module 300 receives premium data 344 from the bank via an electronic media in step 345 . Once the payment has been received in step 346 , the process verifies and validates the data that was received in steps 348 and 349 . If the received data is not valid, the user contacts the bank and asks for the new data in step 350 .
After completing the initial steps of manual or automatic premium processing, the process 338 then applies all the premium data to the billing location in step 352 . If the payment received is within the tolerance limit as determined in step 353 —i.e. the difference of bill due amount and the payment received—the premium process 338 marks the corresponding bill as paid in step 354 . Otherwise, the payment is applied to the suspense account in step 355 . If the payment received is more than the bill amount, as determined in step 357 , the difference is added to the suspense account in step 355 . The process 338 also handles the reversal of premium. In the case where a reversal is required as determined in step 356 , the process 338 marks the bill as a reversal in step 358 and moves the premium amount to the suspense account or another billing location in step 360 depending on the situation. In each instance, data from the premium process 338 is transferred to the general database 310 in the ARDIS module 300 in step 362 .
FIGS. 9A and 9B are a flowchart of the commission process 363 within the ARDIS module 300 . The commission process 363 is preferably executed periodically in a batch process and keeps track of each batch cycle. It picks all the paid premiums for which the commissions have not been accounted during previous batch cycles in step 364 . In step 365 , the commission process 363 retrieves the payment data from the premium payment table in the general database 310 and determines whether the premiums on the policy are submitted gross or net of commissions in step 366 . If the policy is gross, then the commission process 363 retrieves scale, percentage of the scale and year-to-date premium information from the general database 310 in step 368 . The commission process 363 also calculates the commission based on the information retrieved in step 368 . It stores the calculated commission in the commission table and creates an entry into the general ledger in step 370 . For the net policy, the process 363 stores in the commission table in step 372 the commission amount withheld by the producer. In each case, the commission data is stored in step 374 . These steps are repeated for each unaccounted policy with the final step of the loop being step 376 .
The commission process 363 then calculates the gross commission for each producer in step 377 and prepares the commission statement 378 which is printed in step 379 . The process 363 also creates and prints the commission check for the producer in steps 382 and 383 if the commission amount is greater than a predefined amount as determined in step 381 . Once the statements and/or checks have been generated, the printed output is mailed to the appropriate recipients in step 384 .
FIG. 10 is a flowchart of the document generation process 402 . The caseworker 22 requests the policy and certificate generation in step 404 . Based on the caseworker's requests, the process 402 generates the appropriate document in step 405 and, optionally, prints the document in step 406 . In step 407 , the process 402 allows the user to compare the newly generated document with an old document, as in the case of renewal coverage, and allows the user to change the generated document as required. If the generated document is a policy, as determined in step 408 , step 410 of the process 402 generates a letter and the contract along with an image of the policy. If the generated document is determined to be a certificate in step 408 , the process 402 uploads the certificate to the imaging system and generates the appropriate booklets in step 412 . The generated document or documents are transmitted to the client 14 and/or sales representative 16 .
FIG. 11 is a flowchart of the claim module process 502 employed in the Claim module 500 . The claim module process may provide claim processing for various products through different claim sub-modules. Each claim sub-module would apply the claim module process 502 .
Once a claim is received it is electronically imaged in step 504 and the data is stored in step 506 to a claim database 508 . Upon receipt of the claim, verification is made that all required documentation is attached in step 510 . If any documentation is missing, a request is sent to the appropriate party in step 512 requesting the missing information. The claim is then reviewed in step 514 and verification is then made that all required information is included in the documentation in step 516 . If any information is missing, a request is sent to the appropriate party in step 518 requesting the missing information. Additional information that is relevant to the claim, but that is not submitted with the claim may be entered in step 520 and stored in the claim database 508 . The claim is then analyzed to determine whether the claim will be approved or denied in step 522 . If the claim is determined to be approved in step 524 , payment or a waiver is generated in step 526 and the appropriate documents, including checks 24 , are transmitted in step 528 . If the claim is determined to be denied in step 524 , a denial letter is generated in step 530 and transmitted in step 532 .
FIGS. 12 , 13 A and 13 B are flowcharts of the processes employed in the Renewal module 600 . The Renewal module utilizes two major processes: the renewal download process 604 shown in FIG. 12 and the actual renewal process 606 shown in FIGS. 13A and 13B .
The renewal download process 604 is shown in FIG. 12 . In step 608 , the renewal download process 604 downloads existing data either from the ARDIS module general database 310 or from the legacy mainframe system, depending on the age of the group. If the data is downloaded from the ARDIS database, as determined in step 610 , the process 604 retrieves groups whose anniversary date is 90 days before the renewal date, as determined in step 611 . If the data is downloaded from the mainframe system, as determined in step 612 , the process 604 retrieves groups whose anniversary date is 120 days before the renewal date, as determined in step 613 . Once the data has been downloaded and validated, the process 604 stores the updated data in the renewal database in step 614 . After storing the data in the database, the process checks whether the client 14 is a self billed group in step 615 , or a list bill group in step 617 . If it is a self billed group, the process 604 determines the contribution of the client 14 . If the contribution is 100% as determined in step 618 , then it checks whether the eligibility letter 622 has already been received in step 620 . If the eligibility letter 622 has not been received, then it generates the eligibility letter 622 in step 621 . If the eligibility letter 622 has already been received, then it checks for the participation. If the contribution is less than 75% as determined in step 624 , the process 604 then generates the participation letter 625 in step 626 . If the participation is not greater than 75%, the loop ends in step 628 . If the contribution is less than 100% as determined in step 618 , then the process 604 checks whether the census letter 630 has been received in step 629 . If not, then it generates the census letter 630 in step 632 and the loop ends in step 628 .
If the group is list billed as determined in step 617 , then the process 604 checks for the contribution. If the contribution is not 100% as determined in step 619 , then it checks whether an eligibility letter 622 has been received in step 620 . If not, then it generates an eligibility letter 622 in step 621 ; otherwise, it checks whether the participation is less than 75% in step 621 . If the participation is less than 75%, then the process 604 generates the participation letter 625 in step 626 and the loop ends at step 628 .
The renewal process 606 is shown in FIGS. 13A and 13B . During the renewal process 606 all the data is downloaded, verified and the renewal rates are calculated. After downloading the data in step 634 , the process 606 identifies the renewal status for each downloaded renewal. The renewal process 606 also allows the underwriting department 30 to change the renewal rate after the closure in step 669 . If the underwriting department 30 elects to revise the rates, the revised rates are entered in step 670 and the updated renewal status is stored in step 672 . The underwriting department 30 can then either close the transaction or revise the rates in step 674 , but in that case, the user must update the renewal rate into the corresponding ARDIS module general database 310 or in the mainframe system manually in step 676 and store the changes in the database 310 .
As can be seen from the foregoing, throughout the method 10 , no information must be entered into the method 10 more than once, and the information may be built upon throughout the method 10 . Furthermore, no entered information need be made available to insurance company personnel other than as needed, preserving the security of the information.
FIG. 14 shows a preferred configuration of apparatus 700 for quoting, issuing, and administering insurance coverage for a group. Other configurations are contemplated and the following described configuration is not intended to be limiting, but only exemplary.
Two servers 702 and 704 house the test and production databases, respectively, and are connected through a Fiber Distributed Data Interface (“FDDI”) ring 706 . The production database server 704 contains the group client information and is used for production processing. A program development staff primarily uses the test database server 702 to modify existing programs and develop new programs. A similar server configuration exists for the local area network based file servers 708 and 710 which support test and production functions, respectively. This configuration allows the development staff to perform functional testing and the quality assurance and customer acceptance personnel to test developed software to ensure new programs satisfy the standards, quality and functionality before being employed on the production servers.
The sales office 712 has at least one workstation 714 connected to the production database 704 through a series of metaframe servers 716 using a frame relay network 718 . Each sales office workstation 714 is connected to a local printer 720 for the production of proposals 18 and other necessary documents. A facsimile server 722 is used to send generated documents to the client 14 as well as to receive information from the client 14 .
As shown in FIG. 14 , the data center 724 has much of the hardware used in the method 10 , and other hardware is located at a home office location 726 . The home office 726 and data center 724 may be in a single or several locations. Hardware within the home office 726 includes a workstation 728 that is used to print commission checks; an imaging server 730 that is used to create images of generated legal documents; and a users workstation 732 that is used to enter client information, renewal information, and other data not gathered at the sales office 712 . The images of the generated legal documents produced by the imaging server 730 are uploaded to the image database, which is stored on the image database computer 734 , shown as an I.B.M. AS-400. As with the sales office 712 , the workstations within the home office 726 are connected to a local laser printer 736 .
In addition to the above hardware, additional servers are employed to facilitate the transfer and storage of information. An e-mail server 738 , shown as a NOTES/e-mail server, is used to exchange internal e-mail messages between workstations. A transfer server 740 is used to receive premium data from the lock box 742 via modem 743 , which is then uploaded to the database 704 . Optionally, the hardware may be connected to an existing mainframe 744 for the provision of historical information. Ideally, such a connection will be temporary and the mainframe 744 will be phased out of the apparatus 700 configuration.
Thus it can be seen that the invention accomplishes at least all of its stated objectives. | Described is a method and apparatus for automatically quoting, processing, maintaining, claim processing, billing, and renewing life, health and related coverages for clients, especially group clients—without duplicative data entry. An integrated computer system contains several processing modules. The Quoting Engine module produces quotes, maintains and describes coverages available, rates the insurance, and generates a proposal. The Soldcase module administers sales and commission data and provides information regarding the selected coverage to other modules. An Advanced Relational Database Information System module provides billing and premium processing, and administers the payment of commissions. A Document Generator module produces documents such as policies and certificates. A Claims module performs claim adjudication, claim history, and claim payment. The Renewal module automatically monitors and updates information regarding the client and the insurance to determine if renewed coverage should be sold to the client and, if so, at what price. | 6 |
BACKGROUND OF INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a method for managing a power system of a PDA, and more particularly, to a method for switching the PDA among SHUTDOWN mode, ON mode, SCREEN TOGGLE mode, and STANDBY mode to manage the power system of the PDA.
[0003] 2. Description of the Prior Art
[0004] Nowadays, low-polluting electric power applications are advocated and many electric appliances use electric power to operate. A reduction in the volume and the weight of electric appliances makes the appliances more convenient and portable. A PDA (Personal Digital Assistant) is a portable and popular device and can allow users to manage their schedules and to store data. Compared with a desktop or a notebook, it is more convenient for users who have to deal with computer data mobilely like sales and on-line production managers. Like other portable electric appliances, a battery is the main power supply source in the PDA, but the volume of the battery is limited in a PDA. A power control system can alert users to the exhaustion of the volume of the battery and allow users to control the consumption of the volume of the battery. For instance, users can store data, change another battery, or recharge the PDA using an external power supply before the exhaustion of the battery so that data is not lost or so that damage does not occur in the PDA due to over-discharging. In view of the above, an effective and perfect power control system is emphasized in modern industry.
[0005] To reduce the power consumption of a PDA in the present power control system, the power supply of the electric component can be cut or reduced when the system is in an idling state. The power control system in the PDA is capable of detecting whether input buttons, display devices, and other components are switched on. If the power control system does not detect any activity during a certain period, the power supply of the main system will be shut down temporarily. However, in the prior art, the power management of the PDA is usually mainly controlled by the CPU, and the feasibility of using the microprocessor to control the power management of the PDA is neglected. Therefore, besides consuming a lot of system resources, the prior art method is dangerous because the large power consumption of using the CPU to control the power management of the whole system could result in over-discharging. In addition, the most power-consuming part of the PDA is the display panel. The prior art usually neglects to consider the power consumption of the display panel when utilizing the power management of the PDA so that the danger of over-discharging still exists. To solve the above-mentioned problems, first, not only can the technology of the prior art pertaining to the power control system of the microprocessor be utilized, but also the microprocessor can be used to supervise the whole power control system in the PDA. Besides, the display panel and other related peripherals should be taken into consideration of the power management of the PDA.
SUMMARY OF INVENTION
[0006] It is therefore a primary objective of the claimed invention to provide a method for achieving power management for a PDA system to solve the above-mentioned problems of the prior art.
[0007] According to the claimed invention, a method for achieving power management of a PDA is provided. The PDA comprises a CPU for processing data; a microprocessor for supervising the power system of the PDA; and a display module for displaying the data. The method comprises (a)switching the PDA from OFF mode to SHUTDOWN mode, wherein when the PDA is in OFF mode, the CPU, the microprocessor, and the display are all off, and when the PDA is in SHUTDOWN mode, the CPU and the display module are off while the microprocessor is on; (b) after step (a), switching the PDA from SHUTDOWN mode to ON mode, wherein when the PDA is in ON mode, the CPU, the microprocessor, and the display module are all on; (c) after step (b), switching the PDA between ON mode and SCREEN TOGGLE mode, wherein when the PDA is in SCREEN TOGGLE mode, the CPU and the microprocessor are on while the display module is off; and (d) after step (b), switching the PDA between ON mode and STANDBY mode, wherein when the PDA is in STANDBY mode, the CPU is idle, the microprocessor sleeps, and the display module is off, and an operating current of the CPU when the CPU is idle is smaller than the operating current when the CPU is on, and an operating current of the microprocessor when the microprocessor sleeps is smaller than the operating current when the microprocessor is on.
[0008] According to the claimed invention, a PDA capable of managing power of the PDA comprises a power operating system comprising a slide switch for switching the PDA from OFF mode to SHUTDOWN mode; a power button for switching the PDA among SHUTDOWN mode, ON mode, SCREEN TOGGLE mode, and STANDBY mode; and a screen-toggle key for switching the PDA from ON mode to SCREEN TOGGLE mode; a CPU for processing data; a microprocessor for supervising the power operating system; and a display module for displaying the data; wherein when the slide switch is turned on, the PDA is switched from OFF mode to SHUTDOWN mode, wherein when the PDA is in OFF mode, the CPU, the microprocessor, and the display are all off, and when the PDA is in SHUTDOWN mode, the CPU and the display module are off while the microprocessor is on; when the power button is pressed, the PDA is switched from SHUTDOWN mode to ON mode, wherein when the PDA is in ON mode, the CPU, the microprocessor, and the display module are all on; when the screen-toggle key is pressed, the PDA is switched from ON mode to SCREEN TOGGLE mode, wherein when the PDA is in SCREEN TOGGLE mode, the CPU and the microprocessor are on while the display module is off; when the power button is pressed during the PDA being in SCREEN TOGGLE mode, the PDA is switched from SCREEN TOGGLE mode to ON mode; when the PDA is in ON mode with the power button pressed, the PDA is switched from ON mode to STANDBY mode, wherein when the PDA is in STANDBY mode, the CPU is idle, the microprocessor sleeps, and the display module is off; when the power button is pressed repeatedly, the PDA is switched between ON mode and STANDBY mode; an operating current of the CPU when the CPU is idle is smaller than the operating current when the CPU is on, and an operating current of the microprocessor when the microprocessor sleeps is smaller than the operating current when the microprocessor is on.
[0009] It is an advantage of the claimed invention that instead of the CPU, the microprocessor is used to supervise and manage a power managing system of the PDA for reducing the power consumption and avoiding over-discharging damage to the PDA.
[0010] It is an advantage of the claimed invention that a display panel and other related peripherals are all taken into consideration of the power management of the PDA.
[0011] It is an advantage of the claimed invention that when the remaining power volume of the PDA is less than a critical voltage, the microprocessor is capable of switching the CPU from being on to being idle, or preventing the CPU from switching from being idle to being on when the CPU is idle, for avoiding the over-discharging damage to a battery. In addition, when the remaining power volume of the PDA detected by the gas gauge is less than a cut-off voltage, the PDA is switched from SCREEN TOGGLE mode or STANDBY mode to SHUTDOWN mode.
[0012] These and other objectives and advantages of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0013] [0013]FIG. 1 is a functional block diagram of an embodiment of a PDA.
[0014] [0014]FIG. 2 is a state flowchart of the PDA as shown in FIG. 1 in different modes according to the present invention.
[0015] [0015]FIG. 3 is a flowchart of the different voltage values of the PDA as shown in FIG. 1 in different modes according to the present invention.
[0016] [0016]FIG. 4 is a functional block diagram of another embodiment of a PDA.
[0017] [0017]FIG. 5 is a state flowchart of the PDA as shown in FIG. 4 in different modes according to the present invention.
[0018] [0018]FIG. 6 is a flowchart of the different voltage values of the PDA as shown in FIG. 4 in different modes according to the present invention.
[0019] [0019]FIG. 7 is a list showing all the conditions in various modes in the embodiment as shown in FIG. 4.
DETAILED DESCRIPTION
[0020] Please refer to FIG. 1, which is a functional block diagram of an embodiment of a PDA 10 of the present invention. The PDA 10 comprises a CPU 14 , a microprocessor 12 , a display module 16 , and a power operating system 18 . The present embodiment does not include peripherals of the PDA 10 for emphasizing a basic structure of the PDA 10 regarding power management. The user can make use of the power operating system 18 to switch the PDA 10 among various modes. The power operating system 18 comprises a slide switch 20 , a power button 22 , and a screen-toggle key 24 . The display module 16 comprises a display panel 26 and a front light 28 . The display panel 26 can be an LCD panel or an LTPS LCD panel. In addition, inside the PDA 10 , the microprocessor 12 is electrically connected to the power operating system 18 and the CPU 14 of the PDA 10 for controlling the related power system of the PDA 10 . The CPU 14 is also electrically connected to the power operating system 18 , the microprocessor 12 , and the display module 16 of the PDA 10 mainly for controlling the power conditions of the display module 16 .
[0021] The user can switch the PDA 10 among various modes by pressing the slide switch 20 , the power button 22 , and the screen-toggle key 24 of the power operating system 18 . Please refer to FIG. 2, which a state flowchart of the PDA 10 in different modes according to the present invention. When the user turns on the slide switch 20 , the PDA 10 will be switched by the microprocessor 12 from OFF mode to SHUTDOWN mode. When the PDA 10 is in OFF mode, the CPU 14 , the microprocessor 12 , and the display module 16 are all off, and when the PDA 10 is in SHUTDOWN mode, the CPU 14 is off, the microprocessor 12 is on, and the display module 16 is off. After that, when the user presses the power button 22 or the screen-toggle key 24 , the PDA 10 will be switched among SHUTDOWN mode, ON mode, SCREEN TOGGLE mode, and STANDBY mode. As shown in FIG. 2, when the PDA 10 is in SHUTDOWN mode, once the user presses the power button 22 , the microprocessor 12 will switch the PDA 10 from SHUTDOWN mode to ON mode. In ON mode, the CPU 14 , the microprocessor 12 , and the display module 16 are on. Moreover, when the PDA 10 is in ON mode, the user can press the screen-toggle key 24 to utilize the CPU 14 to switch the PDA between ON mode and SCREEN TOGGLE mode; when the PDA 10 is in SCREEN TOGGLE mode, the user can press the screen-toggle key 24 and the power button 22 to switch the PDA 10 back to ON mode. When the PDA 10 is in SCREEN TOGGLE mode, the CPU 14 and the microprocessor 12 are on, and the display module 16 is off. When PDA 10 is in ON mode, the user can press the power button 22 to utilize the microprocessor 12 to switch the PDA 10 between ON mode and STANDBY mode. When PDA 10 is in STANDBY mode, the CPU 14 is idle, the microprocessor 12 sleeps, and the display module 16 is off. From the above-mentioned description, OFF mode, SHUTDOWN mode, ON mode, SCREEN TOGGLE mode, and STANDBY mode are those various modes for describing different power statuses of the PDA 10 . Please notice that most of the modes are mainly controlled and supervised by the microprocessor 12 , and only those modes related to the display module 16 are mainly controlled by the CPU 14 .
[0022] Please continue referring to FIG. 2. When the PDA 10 is in OFF mode, that is, the CPU 14 , the microprocessor 12 , and the display module 16 are off. The display panel 26 and the front light 28 of the display module 16 are off so that no operating current is consumed. When the user turns on the slide switch 20 , the PDA 10 is switched to SHUTDOWN mode, the CPU 14 and the display module 16 are still off while the microprocessor 12 is turned into being on. That is, the microprocessor 12 can operate based on a stable supplied voltage and consume a stable current. The microprocessor 12 consumes less power than the CPU 14 does. Generally, due to that the full operating current of the microprocessor 12 is around several mA, the PDA 10 only consumes little power in SHUTDOWN mode. If the user wants to perform the whole functions of the PDA 10 , the user can press the power button 22 to utilize the microprocessor 12 to switch the PDA 10 from SHUTDOWN mode to ON mode. Then the CPU 14 and the microprocessor 12 are on. Regarding the display module 16 , the display panel 26 is on while the front light 28 will be switched between being off and being on. In brief, the CPU 14 , the display panel 26 , and the microprocessor 12 can respectively fully operate based on a stable supplied voltage. Generally, the full operating current of the CPU 14 is around about one hundred mA to several hundreds mA during maximum operation, which is much higher than the full operating current of the microprocessor 12 . Actually, the full operating current of the display panel 26 is the main power-consuming source of the PDA 10 . When the PDA 10 is in ON mode, if the user does not input any signal into the PDA 10 during a predetermined period of time, the front light 28 will automatically turn off. When PDA 10 is in SCREEN TOGGLE mode, the display panel 26 and front light 28 are off without any power consumption. When PDA 10 is in STANDBY mode, the display panel 26 and front light 28 are also off. Please notice that when the CPU 14 is idle, the operating current of the CPU 14 is much less than the full operating current of the CPU 14 . When the microprocessor 12 sleeps, the microprocessor 12 operates at a clock with a period T and is on during half of the period T and is off during another half of the period T. Therefore, the appropriate period value, which is less than the period value the user spends turning on buttons, can allow the microprocessor 12 to detect any operation from the user during half of the period T in which the microprocessor 12 is on for awakening the microprocessor 12 and the PDA 10 again.
[0023] Please notice, all the designs, including SCREEN TOGGLE mode, automatic switch of the front light 28 from being on to being off, of the present embodiment significantly reduce the power consumption by effectively managing the display panel 26 and the front light 28 . In addition, when the microprocessor 12 sleeps, the operating current of the microprocessor 12 will decrease to several μA which is much less than the value of the full operating current of the microprocessor 12 . In preliminary summary, the PDA 10 can save a lot of power from the display panel 26 , the front light 28 , the microprocessor 12 , and CPU 14 to greatly increase the operating time of the PDA 10 .
[0024] Please refer to FIG. 3, which is a flowchart of the different voltage values of the PDA 10 in different modes according to the present invention. When the remaining power volume of the PDA 10 is less than a critical voltage, if the CPU 14 is on, the microprocessor 12 will switch the CPU 14 to being idle (the PDA 10 is switched to STANDBY mode), if the CPU 14 is idle, the microprocessor 12 will prevent the CPU 14 from being switched to being on for avoiding over-discharging effect to permanently damage the PDA 10 . When the remaining power volume of the PDA 10 is less than a cut-off voltage and the PDA 10 is in STANDBY mode, the PDA 10 will switched from STANDBY mode to SHUTDOWN mode and then the CPU 14 is off. At this moment, only the microprocessor 12 takes charges of supervising the power conditions of the PDA 10 . When the remaining power volume of the PDA 10 is less than a cut-off voltage and the PDA 10 is in SCREEN TOGGLE mode, the PDA 10 will be switched from SCREEN TOGGLE mode to SHUTDOWN mode for avoiding over-discharging damage to the PDA 10 .
[0025] Please refer to FIG. 4, which is a functional block diagram of another embodiment of a PDA 30 of the present invention. The PDA 30 comprises a CPU 34 , a microprocessor 32 , a display module 36 , a power operating system 38 , an LED panel 50 , and a plurality of peripherals 52 . The present embodiment includes the peripherals 52 of the PDA 30 for detailing the power managing system of the present invention. The power operating system 38 comprises a slide switch 40 , a power button 42 , and a screen-toggle key 44 . As with the previous embodiment, the PDA 30 can still be switched among various modes by the power operating system 38 .
[0026] Please continue referring to FIG. 4. The display module 36 comprises a display panel 46 and a front light 48 . The display panel 46 can be an LCD panel or an LTPS LCD panel. The power operating system 38 further comprises a gas gauge 54 for detecting a remaining power volume of the PDA 30 . The peripherals 52 include a memory 56 , a power supply port 58 , and a plurality of input keys 60 . The memory 56 is used for storing data, the power supply port 58 is used for providing external power supply, and the input keys 60 are used for the user to input signals into the PDA 30 . The input keys 60 include at least a hot key 62 . In addition, the microprocessor 32 is electrically connected to the power operating system 38 , the CPU 34 , the peripherals 52 , and the LED panel 50 of the PDA 30 , and the CPU 34 is electrically connected to the power operating system 38 , the microprocessor 32 , and the display module 36 of the PDA 30 mainly for controlling the display module 36 .
[0027] The user can press the slide switch 40 , the power button 42 , and the screen-toggle key 44 of the power operating system 38 to switch the PDA 30 among various modes. Please refer to FIG. 5, which is a state flowchart of the PDA 30 in different modes according to the present invention. When the user turns on the slide switch 40 , the PDA 30 will be switched from OFF mode to SHUTDOWN mode. When the PDA 30 is in OFF mode, the CPU 34 , the microprocessor 32 , the display panel 46 and the front light 48 of the display module 36 , and the memory 56 are off while the input keys 60 sleep and the power supply port 58 is on. When the PDA 30 is in SHUTDOWN mode, the CPU 34 , the memory 56 , the display module 36 , and the input keys 60 are off while the microprocessor 32 is on. As with the previous embodiment, the PDA 30 consumes little power in SHUTDOWN mode. After that, when the user presses the power button 42 or the screen-toggle key 44 , the PDA 30 will be switched among SHUTDOWN mode, ON mode, SCREEN TOGGLE mode, and STANDBY mode. The detailed operations are described in FIG. 5. When the PDA 30 is in SHUTDOWN mode, if the user presses the power button 42 , the microprocessor 32 will switch the PDA 30 from SHUTDOWN mode to ON mode so that the CPU 34 , the microprocessor 32 , the display panel 46 , the memory 56 , and the power supply port 58 are on. However, at this moment, the front light 48 will be switched between being off and being on, and the input keys 60 will be switched between sleeping and being on. That is, if the user does not make use of the PDA 30 for a predetermined period of time, the front light 48 will automatically turn off, and the input keys 60 will be automatically switched from being on to sleeping. All the above-mentioned designs are for saving power. When PDA 30 is in ON mode, the user can press the screen-toggle key 44 to utilize the CPU 34 to switch the PDA 30 between ON mode and SCREEN TOGGLE mode. When the PDA 30 is in SCREEN TOGGLE mode, the user can press the screen-toggle key 44 , the power button 42 , or the hot key 62 to return the PDA 30 to ON mode. When PDA 30 is in SCREEN TOGGLE mode, the CPU 34 , the microprocessor 32 , the memory 56 , and the power supply port 58 are on while the input keys 60 sleep and the display module 36 is off. In addition, when the PDA 30 is in ON mode, the user can press the power button 42 to utilize the microprocessor 32 to switch the PDA 30 between ON mode and STANDBY mode. When PDA 30 is in STANDBY mode, the CPU 34 is idle, the microprocessor 32 sleeps, the display module 36 is off, the memory 56 is in a low-power status, the input keys 60 sleeps, and the power supply port 58 is on. Please notice that, as with the previous embodiment, when the microprocessor 32 sleeps, the microprocessor 32 operates at a clock with a period T and is in ON mode during half of the period T and is in OFF mode during another half of the period T. Therefore, the appropriate period value, which is less than the period value users spend turning on buttons, can allow the microprocessor 32 to detect any operation of users during half of the period T (in which the microprocessor 32 is on) for awakening the microprocessor 32 and the PDA 30 again. Please notice that most of the modes are mainly controlled and supervised by the microprocessor 32 , and only those modes related to the display module 16 are mainly controlled by the CPU 34 .
[0028] Please notice, as with the previous embodiment, all the designs, including SCREEN TOGGLE mode, automatic switch of the front light 48 from being on to being off, of the present embodiment significantly reduce the power consumption by effectively managing the display panel 46 and the front light 48 . In preliminary summary, the PDA 30 can save the a lot of power from the display panel 46 , the front light 48 , peripherals 52 , the microprocessor 32 , and CPU 34 to greatly increase the operating time of the PDA 30 .
[0029] Please refer to FIG. 6, which is a flowchart of the different voltage values of the PDA 30 in different modes according to the present invention. When the remaining power volume of the PDA 30 detected by the gas gauge 54 is lower than a threshold voltage, the microprocessor 32 is capable of transmitting a message to the LED panel 40 so as to produce a flash of light on the LED panel 50 . When the remaining power volume of the PDA 30 is less than a critical voltage, if the CPU 34 is on, the microprocessor 32 will switch the CPU 34 to being idle (the PDA 30 is switched to STANDBY mode), if the CPU 34 is idle, the microprocessor 32 will prevent the CPU 34 from being switched to being on for avoiding over-discharging effect to permanently damage the PDA 30 . When the remaining power volume of the PDA 30 is less than a cut-off voltage and the PDA 30 is in STANDBY mode, the PDA 30 will be switched from STANDBY mode to SHUTDOWN mode and then the CPU 34 is off. At this moment, only the microprocessor 32 takes charges of supervising the power conditions of the PDA 30 . When the remaining power volume of the PDA 30 is less than a cut-off voltage and the PDA 30 is in SCREEN TOGGLE mode, the PDA 30 will be switched from SCREEN TOGGLE mode to SHUTDOWN mode for avoiding over-discharging damage to the PDA 30 .
[0030] Please refer to FIG. 7, which lists all the conditions in various modes in the embodiment as shown in FIG. 4. Please notice that the power supply port 58 as shown in FIG. 4 is divided into DC_VCC and 3.3/5.5V in FIG. 7 according different functions.
[0031] In contrast to the prior art, the present invention provides a method for achieving the whole power management of a PDA. A display panel and other related peripherals are all taken into consideration of the power management of the PDA. In addition, according to the present invention, the PDA can be switched among SHUTDOWN mode, ON mode, SCREEN TOGGLE mode, and STANDBY mode for effectively saving power.
[0032] Those skilled in the art will readily observe that numerous modifications and alterations of the method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims. | A method for achieving power management for a PDA. The PDA includes a CPU for processing data, a microprocessor for supervising power condition of the PDA, and a display module for displaying data and information. The method includes: (a) using the microprocessor and the CPU to switch the PDA from OFF mode to SHUTDOWN mode wherein when the PDA is in OFF mode, the CPU, the microprocessor, and the display are all off, and when the PDA is in SHUTDOWN mode, the CPU and the display module are off while the microprocessor is on; (b) after step (a), switching the PDA from SHUTDOWN mode to ON mode wherein when the PDA is in ON mode, the CPU, the microprocessor, and the display module are on; (c) after step (b), switching the PDA among SHUTDOWN mode, STANDBY mode, and SCREEN TOGGLE mode. | 8 |
TECHNICAL FIELD
The present document relates to optical transmission systems. In particular, the present document relates to high efficiency wavelength division multiplexing (WDM) optical communication systems.
BACKGROUND
Reducing the channel spacing of WDM systems is an efficient way to take full benefit of the optical amplifier bandwidth (which is around 4 THz in current amplifier systems). 100 G systems typically use a symbol rate of 28 Gbaud (PDM-QPSK, Polarization Division Multiplexing—Quadrature Phase Shift Keying) and a channel spacing of 50 GHz. Reducing the channel spacing close to the symbol rate (i.e. reducing the channel spacing close to 28 GHz) is effective in order to increase system capacity (by approximately 50%) with limited transmission reach reduction (by approximately only 10 to 20%). One key challenge in these tight channel spacing configurations is to recover the transmitter clock at the receiver. This is particularly relevant if the transmitted sequences of data symbols are relatively long (as is the case in commercial operation), because the mismatch between the clocks at the transmitter and the receiver increases with time.
WO02/31984A2 describes a method for performing multiple order amplitude modulation. US2004/101311A1 describes a method for the distribution of a synchronization signal in an optical communication system which is inherently asynchronous. U.S. Pat. No. 4,972,408 describes a method of combining and separating a low data rate digital channel with or from the high data rate digital channel of a transmission link.
WO2010/119576A1 describes a method for detecting a skew between parallel light signals generated from a serial data stream.
SUMMARY
The present document addresses the technical problem of clock recovery (also referred to as timing recovery) when using narrow WDM channels, e.g. WDM channels with a channel width or bandwidth D which is close to the symbol rate of the data transmitted over the WDM channels.
According to an aspect, an optical transmitter is described. The optical transmitter is adapted to transmit an optical signal on an optical wavelength division multiplexed (WDM) transmission channel to a corresponding optical receiver. The WDM transmission channel may have a pre-determined bandwidth. The bandwidth may be modified, e.g. on a pre-determined grid having a pre-determined granularity (e.g. 12.5 GHz). The optical transmitter comprises a symbol generation unit adapted to convert input data into a sequence of data symbols at a symbol rate B; with B being a real number greater than zero. The symbol rate B may be in the range of the bandwidth of the WDM transmission channel. In particular, the bandwidth of the WDM transmission channel may be smaller than or equal to the symbol rate B.
The data symbols may comprise respective phases and amplitudes. The phases of the data symbols may correspond to the phases of constellation points of an M ary —Phase Shift Keying (M-PSK) modulation scheme; with M being an integer, M>1. By way of example, the phases of the data symbols may correspond to the phases of the constellation points of a Quadrature Phase Shift Keying (QPSK) modulation scheme with M=4. The amplitudes of the data symbols may be constant at a first amplitude.
Furthermore, the optical transmitter may comprise a digital-to-optical converter adapted to convert a sequence derived from the sequence of data symbols into an optical signal to be transmitted to the optical receiver. The sequence derived from the sequence of data symbols may e.g. be substantially identical to the sequence of data symbols. Alternatively, the sequence derived from the sequence of data symbols may correspond to a filtered (e.g. pulse shape filtered) version of the sequence of data symbols.
The optical transmitter is adapted to provide a clock tone at a tone frequency within the optical signal, wherein the tone frequency is B/N, with N being a real number, N>2. The clock tone may be synchronous with the sequence of data symbols. In other words, the tone frequency may have a fixed relationship with the symbol rate. By way of example, N is constant. The clock tone may be inserted into the sequence of data symbols prior to modulating the sequence derived from the sequence of data symbols onto the optical signal. As indicated above, the WDM transmission channel may have a bandwidth D. The tone frequency (i.e. the integer N) may be selected such that it is smaller than half of the channel width D, i.e. B/N<D/2.
The insertion of the clock tone into the sequence of data symbols is achieved by providing a symbol generation unit which comprises an amplitude modulation unit and which is adapted to generate a sequence of data symbols, wherein the amplitudes of the data symbols are constant at the first amplitude, apart from every N th data symbol in the sequence of data symbols having a second amplitude other than the first amplitude, N may be an integer. Alternatively, the symbol generation unit may be adapted to generate a sequence of data symbols, wherein the amplitudes of the data symbols are constant at the first amplitude. Furthermore, the optical transmitter may comprise an amplitude modulation unit adapted to modulate (e.g. to modify) the amplitude of every N th data symbol in a sequence derived from the sequence of data symbols, thereby creating a modulated sequence of data symbols. In such a case, the digital-to-optical converter may be adapted to convert a sequence derived from the modulated sequence of data symbols into the optical signal.
The amplitude of every N th data symbol in the sequence of data symbols or in the sequence derived from the sequence of data symbols may be increased with respect to the first amplitude. A ratio between the first amplitude and the modulated (e.g. increased) amplitude may be adjustable, thereby adjusting a modulation depth and an amplitude of the clock tone, and thereby improving clock recovery at the optical receiver.
The digital-to-optical converter typically comprises a digital-to-analogue converter. The digital-to-analogue converter may be adapted to convert the sequence derived from the modulated sequence of data symbols into an analogue electrical signal. Furthermore, the digital-to-optical converter may comprise an optical modulator adapted to modulate an optical carrier signal with the analogue electrical signal; thereby yielding the optical signal.
The optical transmitter may be adapted to generate a polarization division multiplexed (PDM) optical signal comprising a first polarization component and a second polarization component. In such cases, a clock tone may be inserted in one or both of the polarization components of the PDM optical signal. By way of example, the first polarization components may be modulated with a sequence derived from a first modulated sequence of data symbols and/or the second polarization components may be modulated with a sequence derived from a second modulated sequence of data symbols.
The optical transmitter may comprise a pulse shaping filter. The pulse shaping filter may be positioned upstream of the amplitude modulation unit (i.e. pulse shaping may be performed prior to amplitude modulation). In such cases, the pulse shaping filter may be adapted to filter the sequence of data symbols. The filtered sequence of data symbols may be the sequence derived from the sequence of data symbols which is processed by the amplitude modulation unit. This configuration may be beneficial in order to provide a clock tone with a controlled clock tone amplitude. Alternatively, the pulse shaping filter may be positioned downstream of the amplitude modulation unit (i.e. pulse shaping may be performed subsequent to amplitude modulation). In such cases, the pulse shaping filter may be adapted to filter the modulated sequence of data symbols. This configuration may be beneficial in order to increase the signal-to-noise ratio at the corresponding optical receiver.
According to a further aspect an optical receiver is described. The optical receiver is adapted to receive an optical signal on an optical wavelength division multiplexed (WDM) transmission channel from a corresponding optical transmitter. The optical receiver comprises a reception unit adapted to convert the optical signal received from the optical transmitter into an analogue or digital signal. Typically, the reception unit comprises a coherent detection unit (if the optical receiver is a coherent detector), thereby yielding the analogue signal. Furthermore, the reception unit typically comprises one or more analogue-to-digital converters adapted to convert the analogue signal into a digital signal.
The analogue or digital signal is representative of (or comprises) a sequence of data symbols at a symbol rate B; with B being a real number greater than zero. Furthermore, the analogue or digital signal is representative of a clock tone at the tone frequency of B/N. In particular, the amplitude of every N th data symbol in the sequence of data symbols may be increased; N being a real number (e.g. an integer), N>2. The optical receiver comprises a clock recovery unit adapted to adjust a clock of the optical receiver to a clock of the transmitter, based on a spectrum of the analogue or digital signal at frequencies of substantially −B/N and/or +B/N. In particular, the clock recovery unit may be adapted to apply a filter and square method to spectral components of the analogue or digital signal at the frequencies of substantially −B/N and +B/N.
According to a further aspect, an optical transmission system adapted for WDM transmission is described. The optical transmission system comprises an optical transmitter according to any of the aspects outlined in the present document and an optical receiver according to any of the aspects outlined in the present document.
According to another aspect, an optical signal representative of a sequence of data symbols is described. The data symbols comprise respective phases and amplitudes. The phases of the data symbols correspond to the phases of constellation points of an M ary —Phase Shift Keying (M-PSK) modulation scheme; with M being an integer, M>1. The amplitudes of the data symbols are substantially constant at a first amplitude, apart from every N th data symbol in the sequence of data symbols having a second amplitude higher than the first amplitude. The second amplitude may be substantially constant.
According to a further aspect, a method for enabling clock recovery at an optical receiver of an optical WDM transmission system is described. The method comprises generating a sequence of data symbols at a symbol rate B; with B being a real number greater than zero. The sequence of data symbols may be representative of input data. Furthermore, the method comprises modulating (e.g. modifying) an amplitude of every N th data symbol in a sequence derived from the sequence of data symbols, thereby creating a modulated sequence of data symbols; wherein N is an integer; wherein N>2. In addition, the method comprises converting a sequence derived from the modulated sequence of data symbols into an optical signal to be transmitted to the optical receiver.
According to a further aspect, a software program is described. The software program may be adapted for execution on a processor and for performing the method steps outlined in the present document when carried out on a computing device.
According to another aspect, a storage medium is described. The storage medium may comprise a software program adapted for execution on a processor and for performing the method steps outlined in the present document when carried out on a computing device.
According to a further aspect, a computer program product is described. The computer program may comprise executable instructions for performing the method steps outlined in the present document when executed on a computer.
It should be noted that the methods and systems including its preferred embodiments as outlined in the present patent application may be used stand-alone or in combination with the other methods and systems disclosed in this document. Furthermore, all aspects of the methods and systems outlined in the present patent application may be arbitrarily combined. In particular, the features of the claims may be combined with one another in an arbitrary manner.
DESCRIPTION OF THE DRAWINGS
The invention is explained below in an exemplary manner with reference to the accompanying drawings, wherein
FIG. 1 a illustrates the principle of an example clock recovery method;
FIGS. 1 b to 1 e show spectra of example 112 Gb/s PDM-QPSK signals used for clock recovery;
FIG. 2 a shows the block diagram of an example optical transmission system;
FIG. 2 b illustrates an example modulation scheme for improved clock recovery;
FIG. 2 c illustrates another example modulation scheme for improved clock recovery; and
FIG. 3 shows optical spectra of example 112 Gb/s PDM-QPSK signals for improved clock recovery.
DETAILED DESCRIPTION
Optical communication systems typically comprise separate clocks (e.g. VCO, Voltage controlled oscillators) at their transmitters and receivers. The clocks at a transmitter and a receiver typically deviate from one another. This may have an impact on the performance of the communication link provided by the transmitter and the receiver. If the clock of the transmitter operates (and transmits data symbols) at a higher rate than the clock of the receiver, the receiver may miss out data symbols. On the other hand, if the clock of the transmitter operates at a lower rate than the clock of the receiver, the receiver may create copies of some of the data symbols. In any case, the mismatch of the clocks typically leads to an increased bit error rate and an increased outage probability of the communication link.
It is therefore desirable to adjust the clock at the receiver to the clock at the transmitter (or vice versa). In particular, it is desirable to recover clock (or timing) information from the received data symbols itself without the need for an explicit clock synchronization scheme.
In optical transmission systems data symbols are continuously transmitted from the transmitter to the receiver (in a so called circuit mode or a so called synchronous mode). As such, the receiver receives a continuous stream of data symbols at the symbol rate. The symbol rate corresponds to the clock at the transmitter. This means that the stream of data symbols comprises information regarding the clock at the transmitter and consequently, this clock information can be recovered at the receiver by determining the symbol rate from the continuous stream of data symbols.
The clock information may be extracted from the continuous stream of data symbols by analyzing the phase of spectral components which are located at half the symbol rate (i.e. by analyzing the phase of spectral components at −14 GHz and +14 GHz in case of a symbol rate of 28 Gbaud). This is illustrated in the frequency diagram 100 of FIG. 1 a , where the spectrum 101 of a stream of data symbols is illustrated. In the illustrated example, the stream of data symbols has a symbol rate of B. The spectral components 103 , 102 of the spectrum 101 at the frequencies −B/2 and +B/2, respectively, may be used to determine information regarding a difference of the clock frequency at the transmitter and the clock frequency at the receiver. In other words, the difference between the clock at the receiver and the clock at the transmitter can be determined by analyzing the spectrum of the received stream of data symbols at the frequency of −B/2 (reference numeral 103 ) and +B/2 (reference numeral 102 ). An example method for recovering the clock based on the spectrum of the received stream of symbols is described in M. Oerder and H. Meyr, “Digital Filter and Square Timing Recovery”, IEEE Transactions on Communications, Vol. 36, No. 5, May 1988, pp. 605-612. This method is typically referred to as the “filter and square” method for clock recovery. The description of this method (notably section II of the above mentioned document) is incorporated by reference.
As indicated above, clock recovery methods (as e.g. the above mentioned filter and square method) typically analyze the spectrum of the received stream of data symbols at the frequencies of +/−B/2, wherein B is the symbol rate of the stream of data symbols. It has been observed that the information at this part of the spectrum may be corrupted by an imperfect phase response of transmitter and/or receiver optical filters and also by the crosstalk incurred on a particular WDM channel from adjacent WDM channels. This is particularly the case when narrow channel spacing is used (e.g. channel spacing in the range of B). Consequently, when reducing the width of WDM channels in order to increase the spectral efficiency of the WDM channels (i.e. in order to increase the capacity of the overall communication path), the performance of clock recovery decreases, due to increased corruption at the edges (i.e. at the frequencies +/−B/2) of the spectrum of the received stream of data symbols.
This is illustrated in FIGS. 1 b to 1 e . FIG. 1 b shows the spectrum 105 of a 112 Gb/s PDM-QPSK signal subject to 50 GHz supergaussian optical filtering (i.e. subject to transmission over a WDM channel with a 50 GHz bandwidth) and subject to 16 GHz baseband electrical filtering of the ADC at the optical receiver. FIG. 1 c shows the spectrum 106 of a 112 Gb/s PDM-QPSK signal subject to 25 GHz supergaussian optical filtering (i.e. subject to transmission over a WDM channel with a 25 GHz bandwidth) and subject to 16 GHz baseband electrical filtering of the ADC at the optical receiver. It can be seen that due to the optical filtering, the frequencies of the spectrum 106 are limited to +/−12.5 GHz (i.e. to +/−half of the bandwidth D of the WDM channel). In FIGS. 1 b to 1 e the frequencies +/−B correspond to +/−the symbol rate B. FIGS. 1 d and 1 e show the spectra 110 , 120 of the squared 112 Gb/s PDM-QPSK signal subject to 50 GHz and 25 GHz optical filtering, respectively. The spectrum 110 comprises peaks 111 at the frequencies+/−B. These peaks 111 can be used to recover the clock. On the other hand, it can be seen that in case of 25 GHz supergaussian optical filtering due to a reduced channel spacing of 25 GHz (instead of 50 GHz) the resulting spectrum 120 of the squared 112 Gb/s PDM-QPSK signal is corrupted at +/−28 GHz (i.e. at +/−B in case of a symbol rate of B=28 Gbaud). In particular, it can be seen that the spectrum 120 does not comprise the peaks 111 at +/−B, such that clock recovery is not possible.
FIG. 2 a illustrates an example optical transmission system 200 comprising an optical transmitter 210 , an optical transmission path 250 and an optical receiver 230 . The transmitter 210 comprises a first digital signal processor 218 , which may e.g. be implemented as an ASIC (Application-specific integrated circuit). In the illustrated example a transmitter 210 for polarization multiplexed optical signals is depicted. The first digital signal processor 218 provides two sequences of data symbols (e.g. QPSK symbols) for the two polarizations of the optical signal, respectively (within two symbol generation units 211 ). The two sequences of data symbols are filtered by a bank of two transmitter filters 212 (also referred to as pulse shaping filters) for the two polarizations of the optical signal, respectively. In an embodiment, the two transmitter filters 212 are identical, however, in other embodiments, the two transmitter filters 212 are specific for the respective polarizations of the optical signal. In addition, the transmitter 210 may comprise a Look Up Table (LUT) unit 213 . The LUT unit 213 may be adapted to pre-emphasize the (modulated) sequence of data symbols in order to compensate for a nonlinear behaviour of the subsequent modulators 216 . A pair of Digital-to-Analogue-Converters (DAC) 214 is used to convert the filtered sequences of data symbols 211 into a pair of electrical signals. The pair of electrical signals is used to modulate the two polarizations of the optical signal which is transmitted over the transmission path 250 (using drivers 215 and modulators 216 , e.g. Mach-Zehnder-Modulators, MZM).
The optical receiver 230 illustrated in FIG. 2 a is a coherent optical receiver which is configured to convert the received optical signal into a pair of complex digital signals, wherein each digital signal comprises an in-phase component and a quadrature-phase component. For this purpose, the coherent receiver may comprise a coherent detector and a bank of Analogue-to-Digital Converters (ADC) 231 . Furthermore, the optical receiver 230 comprises a second digital signal processor 238 (e.g. an ASIC) which processes the pair of digital signals, in order to recover the two sequences of symbols in the decision units 236 . The processing of the pair of digital signals typically comprises CD compensation 232 , Digital Clock Recovery (DCR) 233 , polarization demultiplexing 234 and carrier frequency/carrier phase estimation 235 . The clock recovery unit 233 may perform a clock recovery method as outlined in the present document.
In the present document, a transmitter 210 is described which generates an optical signal (representative of or comprising a sequence of data symbols) for transmission to the optical receiver 230 , wherein the optical signal allows for an improved clock recovery/timing recovery at the optical receiver 230 . In particular, it is proposed to add a low speed tone to the sequence of data symbols at the transmitter side, wherein the low speed tone is preferably synchronous with the symbol rate. In an example case, a 7 GHz tone may be added to a 28 Gbaud signal when filtered in a 25 GHz grid respecting the condition 7 GHz<12.5 GHz.
In other words, it is proposed to add a repeating event into the stream of data symbols, wherein the repeating event has a frequency which is lower than the symbol rate. By way of example, the repeating event may have a frequency of B/N, wherein B is the symbol rate and wherein N is an integer, N>2, e.g. N=4. The frequency B/N of the repeating event may be smaller than half the bandwidth D of the transmission channel, i.e. B/N<D/2. By adding a repeating event at reduced frequency to the stream of data symbols, the clock recovery unit 233 at the optical receiver 230 is enabled to recover the clock by analyzing the spectrum of the received optical signal at frequencies lower than B/2, i.e. at frequencies which are less affected by distortions incurred on the optical transmission path 250 . In particular, the clock recovery unit 233 is enabled to recover the clock by analyzing the spectrum of the received optical signal at the frequencies −B/N and/or +B/N, i.e. at the frequencies of the repeating event (also referred to as the tone or the clock tone).
FIG. 2 b illustrates an example transmitter 210 which may be used to insert a repeating event at reduced frequency into the stream of data symbols. Furthermore, FIG. 2 b illustrates a stream 260 of data symbols comprising a repeating event at a reduced frequency. A tone (or a repeating event) at reduced frequency (e.g. at B/4) may be inserted into the stream 260 of data symbols by increasing the amplitude of some of the data symbols in a repetitive manner. In the illustrated example, the amplitude of every fourth data symbol 262 is increased compared to the amplitude of the other data symbols 261 . In other words, the amplitude of the data symbols 261 , 262 is modulated, such that every fourth data symbol 262 has an increased amplitude. The extent of the difference between the default amplitude (of the conventional symbols 261 ) and the increased amplitude (of the emphasized symbols 262 ) may be referred to as the modulation depth. The values R/4, 3R/4, 5R/4 and 7R/4 in the symbols 261 , 262 of FIG. 2 b refer to the possible values of example QPSK symbols 261 , 262 .
The transmitter 210 of FIG. 2 b comprises a tone insertion unit 220 . In the illustrated example, the tone insertion unit 220 is configured to increase the amplitude of every N th data symbol 262 . The tone insertion unit 220 may be positioned downstream of the pulse shaping filter unit 212 . The tone information comprised within the stream 260 of data symbols may be used at the receiver 230 to lock the receiver clock onto the transmitter clock using for example the filter and square technique indicated above. For this purpose, the clock recovery unit 233 of the receiver 230 may analyze the spectral component of the spectrum of the received optical signal at the frequencies −B/N and +B/N. In case of N>2, these frequencies are typically unaffected by distortions incurred by the narrow channel spacing of the WDM channels. In other words, the tone information at reduced frequency enables clock recovery, even in cases of highly dense WDM channels.
FIG. 2 c shows an example transmitter 210 , wherein the tone insertion unit 220 is positioned upstream of the pulse shaping filter unit 212 (i.e. where tone insertion/amplitude modulation is performed prior to pulse shaping). This may be beneficial in order to improve the signal-to-noise ratio at the corresponding optical receiver 230 , as the signal which is transmitted over the transmission path 250 is pulse shaped. On the other hand, the amplitude of the inserted clock tone may be reduced due to the filtering in the pulse shaping filter unit 212 .
In the example of a 112 Gb/s PDM-QPSK transmission system 200 and in the example of an increase of the amplitude of every fourth (N=4) QPSK symbol 262 , a tone at 7 GHz is generated by the transmitter 210 of FIG. 2 b . It can be seen from the diagrams 300 and 310 of FIG. 3 that the tone at 7 GHz (reference numerals 301 , 302 , 311 , 312 ) is detectable even in the presence of a strong filtering corresponding to the use of a (narrow) 25 GHz spacing grid, i.e. corresponding to the transmission via a WDM channel having a width of 25 GHz. In such cases, the ratio between the channel spacing (25 GHz) and the baud rate (28 GHz) is 0.89, i.e. smaller than 1. The diagrams 300 and 310 show the spectrum of the intensity of the received sequence of symbols of a 112 Gb/s PDM-QPSK optical signal in a 25 GHz WDM channel grid. In the illustrated example, the spectra of the squared signals are shown. In the case of diagram 300 the modulation depth for the 7 GHz clock tone was higher than in the case of diagram 310 . In other words, the modulation depth in diagram 300 is higher than the modulation depth in diagram 310 . It can be seen that the peaks 301 , 302 at the tone frequency of 7 GHz increase within increasing modulation depth. Consequently, the performance of clock recovery at the receiver 230 increases with increasing modulation depth. Furthermore, it can be seen that even when determining the spectrum of the squared signal, the peaks 301 , 302 are detectable at the tone frequency of B/N.
It should be noted that the performance of the clock recovery may be increased by averaging across succeeding blocks or frames of symbols. By way of example, the spectrum of a stream of symbols may be determined based on a block of succeeding symbols (e.g. a block of 1024 symbols). For this purpose, the block of symbols may be transformed into the frequency domain, e.g. using a Fast Fourier Transform (FFT). The spectra of a plurality of blocks of symbols (e.g. of 10 blocks of symbols) may be averaged, thereby increasing the performance for the extraction of the clock tone and for the clock recovery, even at relatively low modulation depths.
On the other hand, it should be noted that the insertion of a clock tone into the stream 260 of data symbols may impact the Optical Signal to Noise Ratio (OSNR) of the transmission system 200 . The performance of the optical transmission system 200 for 112 Gb/s PDM-QPSK data may be analyzed. It can be shown that the insertion of a clock tone results only in a relatively small penalty, especially when using a relatively small modulation depth. Furthermore, it can be shown that the penalty decreases with decreasing modulation depth.
As such, the penalty added by the overmodulation (i.e. by the modulation of the amplitude of the symbols 262 ) is relatively small. This penalty is low compared to the penalty coming from intersymbol interference or from WDM crosstalk. Furthermore, the penalty due to overmodulation is relatively low compared to the OSNR penalty induced when changing the modulation format from QPSK to e.g. QAM16 in order to reduce the symbol rate at constant bit rate. The penalty when changing the modulation format is typically in the range of 7 dB or more. This means that the transmission of a PDM-QPSK signal at a symbol rate which is in the range of the width of the WDM transmission channel provide a higher performance than the transmission of signals using a constellation having a higher number of constellation points (e.g. QAM16), even when inserting a clock tone into the PDM-QPSK signal.
As can be seen from the diagrams 300 , 310 of FIG. 3 , the intensity spectrum of the stream 160 of data symbols comprises peaks 301 , 302 , 311 , 312 at the frequencies −B/N and +B/N. Due to the presence of peaks 301 , 302 , 311 , 31 , the spectral component at the frequencies −B/N and +B/N may be extracted in a reliable manner. Furthermore the phase information of the spectral components at the frequencies −B/N and +B/N is less corrupted than the phase information of the spectral component at frequencies −B/2 and +B/2, if N>2. Hence, clock recovery methods (e.g. the filter and square method indicated above) can still be applied, even in the case of narrow filtering (e.g. when using a channel bandwidth which is smaller than the symbol rate). The objective of such clock recovery methods may be to measure the phase of the 7 GHz tone (i.e. the B/N tone) and to maintain the phase substantially constant by adjusting the clock frequency at the receiver 230 . This can be done in the analogue signal domain or in the digital signal domain (the latter case being illustrated by the clock recovery unit 233 of FIG. 2 a ). The phase of the clock tone can be obtained by calculating the angle value of the Discrete Fourier Transform (DFT) of the spectral component at 7 GHz (i.e. at the frequency B/N).
It should be noted that as a result of inserting a clock tone, the computational complexity of the clock recovery methods can be reduced. It has been found that the inserted B/N clock tone can be recovered from the spectrum of the received signal directly, without the need to determine the spectrum of the received squared signal. Hence, clock recovery can be performed without the need of oversampling and squaring of the received signal, thereby reducing the computational complexity for clock recovery.
The creation of a stream 260 of symbols having symbols 261 at a first amplitude and symbols 262 at a second, increased, amplitude may be viewed as the overlay of conventional QPSK modulation (i.e. phase modulation) and amplitude modulation. The use of amplitude modulation may impact the Digital-to-Analogue Converter (DAC) 214 which needs to generate an analogue signal at an increased amplitude for every N th symbol. In other words, the DAC 214 may need to provide sufficient dynamic range and resolution to handle the symbols 261 , 262 at different amplitudes.
In the present document, a scheme for enabling clock recovery in dense WDM transmission channels is described. The scheme allows a reliable clock recovery even in situations where the width of a WDM transmission channel lies in the range of the symbol rate of the data transmitted over the WDM transmission channel. The scheme makes use of the insertion of a clock tone into a stream of data symbols, wherein the clock tone has a frequency smaller than half the symbol rate of the stream of data symbols.
As a result of a reliable clock recovery, narrow WDM channel spacing may be used in order to increase the number of WDM channels which can pass within an optical amplifier. This means that the proposed clock recovery scheme enables the increase of the throughput of optical transmission systems. The proposed scheme is particularly interesting for undersea optical transmission systems, but also for terrestrial optical transmission systems, e.g. using gridless or variable bandwidth ROADM (Reconfigurable Optical Add Drop Multiplexers).
It should be noted that the description and drawings merely illustrate the principles of the proposed methods and systems. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody the principles of the invention and are included within its spirit and scope. Furthermore, all examples recited herein are principally intended expressly to be only for pedagogical purposes to aid the reader in understanding the principles of the proposed methods and systems and the concepts contributed by the inventors to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Moreover, all statements herein reciting principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to encompass equivalents thereof.
Furthermore, it should be noted that steps of various above-described methods and components of described systems can be performed by programmed computers. Herein, some embodiments are also intended to cover program storage devices, e.g., digital data storage media, which are machine or computer readable and encode machine-executable or computer-executable programs of instructions, wherein said instructions perform some or all of the steps of said above-described methods. The program storage devices may be, e.g., digital memories, magnetic storage media such as a magnetic disks and magnetic tapes, hard drives, or optically readable digital data storage media. The embodiments are also intended to cover computers programmed to perform said steps of the above-described methods.
In addition, it should be noted that the functions of the various elements described in the present patent document may be provided through the use of dedicated hardware as well as hardware capable of executing software in association with appropriate software. When provided by a processor, the functions may be provided by a single dedicated processor, by a single shared processor, or by a plurality of individual processors, some of which may be shared. Moreover, explicit use of the term “processor” or “controller” should not be construed to refer exclusively to hardware capable of executing software, and may implicitly include, without limitation, digital signal processor (DSP) hardware, network processor, application specific integrated circuit (ASIC), field programmable gate array (FPGA), read only memory (ROM) for storing software, random access memory (RAM), and non volatile storage. Other hardware, conventional and/or custom, may also be included.
Finally, it should be noted that any block diagrams herein represent conceptual views of illustrative circuitry embodying the principles of the invention. Similarly, it will be appreciated that any flow charts, flow diagrams, state transition diagrams, pseudo code, and the like represent various processes which may be substantially represented in computer readable medium and so executed by a computer or processor, whether or not such computer or processor is explicitly shown. | An exemplary method and apparatus are provided for high efficiency wavelength division multiplexing (WDM) optical communication systems. An optical transmitter adapted to transmit an optical signal on an optical WDM transmission channel to a corresponding optical receiver is described. The optical transmitter comprises a symbol generation unit adapted to convert input data into a sequence of data symbols at a symbol rate B; with B being a real number greater zero; an amplitude modulation unit adapted to modulate an amplitude of every N th data symbol in a sequence derived from the sequence of data symbols, thereby creating a modulated sequence of data symbols; wherein N is an integer; wherein N>2; and a digital-to-optical converter adapted to convert a sequence derived from the modulated sequence of data symbols into an optical signal to be transmitted to the optical receiver. | 7 |
BACKGROUND
One useful aspect of semiconductor-on-insulator (SOI) structures is that they permit the use of high-voltage SOI devices, such as diodes, field effect transistors (FETs), thyristors, and bipolar transistors. Still higher voltages may be achieved by connecting a plurality of such devices in series. However, doing so increases the difference in voltage potential between the device and an underlying substrate. This difference increases in each downstream device in the series. As such, the type and number of high-voltage SOI devices that may be connected in series is ultimately limited by the difference in voltage potential between the terminal device and its underlying substrate. Too great a difference in voltage potential will result in degradation of the breakdown voltage (V br ) of the series device, making the device “leaky.” This can adversely impact the efficiency of the series device, sometimes to a degree that the series device fails. For example, in the case of five high-voltage (i.e., 30 V) diodes connected in series, the voltage at the terminal diode would theoretically be 150 V. However, at or near the terminal diode, this may result in too great a difference in voltage potential with the substrate, resulting in the voltage at the terminal diode being less than 150 V.
FIG. 1 shows an integrated circuit 100 including a substrate 10 , a buried oxide (BOX) layer 20 , and a semiconductor layer 30 . Within semiconductor layer 30 are a plurality of HV SOI devices, here shown as diodes 40 A- 40 D, connected in series. Diode 40 A comprises a p-doped portion 42 A and n-doped portion 44 A. For the sake of clarity, the p-doped portions and n-doped portions of diodes 40 B-D are not labeled, but are similar to p-doped portion 42 A and n-doped portion 44 A of diode 40 A.
As can be seen in FIG. 1 , a difference in voltage potential 41 A between diode 40 A and substrate 10 is less than a difference in voltage potential 41 B between diode 40 B and substrate 10 . A difference in voltage potential 41 C between diode 40 C and substrate 10 is greater than difference in voltage potential 41 B, and a difference in voltage potential 41 D between diode 40 D (the terminal diode) and substrate 10 is greater still. As noted above, difference in voltage potential 41 D may be so great that the breakdown voltage degrades, resulting in voltage leakage.
SUMMARY
Integrated circuits having doped bands in a substrate and beneath high-voltage semiconductor-on-insulator (SOI) devices are provided.
A first aspect of the invention provides an integrated circuit comprising: a semiconductor-on-insulator (SOI) wafer including: a substrate; a buried oxide (BOX) layer atop the substrate; and a semiconductor layer atop the BOX layer; a plurality of high voltage (HV) devices connected in series within the semiconductor layer; a doped band within the substrate and below a first of the plurality of HV devices; and a contact extending from the semiconductor layer and through the BOX layer to the doped band.
A second aspect of the invention provides an integrated circuit comprising: a semiconductor-on-insulator (SOI) wafer including: a substrate; a buried oxide (BOX) layer atop the substrate; and a semiconductor layer atop the BOX layer; at least one high voltage (HV) device within the semiconductor layer; an n-doped band within the substrate and below the at least one HV device; and a contact extending from the semiconductor layer and through the BOX layer to the n-doped band.
A third aspect of the invention provides an integrated circuit comprising: a semiconductor-on-insulator (SOI) wafer including: a p-type substrate; a buried oxide (BOX) layer atop the substrate; and a semiconductor layer atop the BOX layer; a first high voltage (HV) device and a second HV device connected in series within the semiconductor layer; a first n-doped band within the substrate and below the first HV device; a second n-doped band within the substrate and below the second HV device; a first contact extending from the semiconductor layer and through the BOX layer to the first n-doped band; and a second contact extending from the semiconductor layer and through the BOX layer to the second n-doped band, wherein the first n-doped band and the second n-doped band are separated within the p-type substrate by a space, a portion of the first n-doped band extends laterally beyond an end of the first HV device, and a portion of the second n-doped band extends laterally beyond an end of the second HV device.
A fourth aspect of the invention provides a semiconductor-on-insulator (SOI) wafer including: a substrate; a buried oxide (BOX) layer atop the substrate; a semiconductor layer atop the BOX layer; a first doped band within the substrate; a second doped band within the substrate; a first contact extending from the semiconductor layer and through the BOX layer to the first doped band; and a second contact extending from the semiconductor layer and through the BOX layer to the second doped band.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
These and other features of this invention will be more readily understood from the following detailed description of the various aspects of the invention taken in conjunction with the accompanying drawings that depict various embodiments of the invention, in which:
FIG. 1 shows a schematic cross-sectional view of an integrated circuit having a plurality of semiconductor-on-insulator (SOI) devices connected in series.
FIG. 2 shows a schematic cross-sectional view of an integrated circuit according to an embodiment of the invention.
FIG. 3 shows a schematic cross-sectional view of an integrated circuit according to an other embodiment of the invention.
FIG. 4 shows a schematic cross-sectional view of an integrated circuit according to yet another embodiment of the invention.
FIG. 5 shows a partial schematic cross-sectional view of an integrated circuit according to still another embodiment of the invention.
FIG. 6 shows a schematic cross-sectional view of an integrated circuit according to yet another embodiment of the invention.
It is noted that the drawings of the invention are not to scale. The drawings are intended to depict only typical aspects of the invention, and therefore should not be considered as limiting the scope of the invention. In the drawings, like numbering represents like elements between the drawings.
DETAILED DESCRIPTION
FIG. 2 shows an integrated circuit 200 according to an embodiment of the invention. As in FIG. 1 , wafer 200 includes a substrate 110 , BOX layer 120 , semiconductor layer 130 , and a plurality of diodes 140 A- 140 D within semiconductor layer 130 . While shown herein as diodes, it should be understood that embodiments of the invention may employ one or more other devices, including but not limited to a field effect transistor (FET), a thyristor, and a bipolar transistor. Wafer 200 also includes a contact 150 A disposed adjacent diode 140 A and extending from semiconductor layer 130 , through BOX layer 120 , and contacting an n-doped band 152 A within substrate 110 . Again, for the sake of clarity, only the n-doped bands and contacts of diodes 140 B- 140 D necessary for illustration of the depicted embodiment of the invention are labeled in FIG. 2 .
Substrate 110 and/or semiconductor layer 130 may include silicon (p-doped, n-doped, and/or undoped), high-resistivity silicon, germanium, silicon germanium, silicon carbide, and those consisting essentially of one or more III-V compound semiconductors having a composition defined by the formula Al X1 Ga X2 In X3 As Y1 P Y2 N Y3 Sb Y4 , where X1, X2, X3, Y1, Y2, Y3, and Y4 represent relative proportions, each greater than or equal to zero and X1+X2+X3+Y1+Y2+Y3+Y4=1 (1 being the total relative mole quantity). Other suitable substrates include II-VI compound semiconductors having a composition Zn A1 Cd A2 Se B1 Te B2 , where A1, A2, B1, and B2 are relative proportions each greater than or equal to zero and A1+A2+B1+B2=1 (1 being a total mole quantity). In some embodiments, the substrate 10 may include amorphous or polycrystalline silicon.
BOX layer 120 may include, for example, oxide, silicon oxide, silicon dioxide, silicon oxynitride, silicon nitride (Si 3 N 4 ), tantalum oxides, alumina, hafnium oxide (HfO 2 ), hafnium silicate (HfSi), plasma-enhanced chemical vapor deposition oxide, tetraethylorthosilicate (TEOS), nitrogen oxides, nitrided oxides, aluminum oxides, zirconium oxide (ZrO 2 ), zirconium silicate (ZrSiO x ), high K (K>5) materials, and/or combinations thereof.
Contact 150 A may include any conductive material, including, but not limited to, polysilicon, tungsten, silicon, and/or combinations thereof. Other useful materials include, for example, aluminum, an aluminum-copper alloy, cobalt, cobalt silicide, copper, metal silicide, nickel, nickel silicide, a nitrided metal, palladium, platinum, a refractory metal, such as ruthenium, tantalum nitride, titanium, titanium aluminum nitride, titanium nitride, titanium silicide, a titanium-tungsten alloy, and/or combinations thereof.
Dopants useful in forming, for example, n-doped band 152 A include, but are not limited to, phosphorus, arsenic, antimony, sulphur, selenium, tin, silicon, and carbon. P-type dopants include, for example, but are not limited to: boron, indium, and gallium.
N-doped band 152 A shields diode 140 A, such that a difference in voltage potential 141 A between diode 140 A and substrate 110 is minimized. Thus, as can be seen in FIG. 2 , difference in voltage potential 141 A is substantially the same as the differences in voltage potentials 141 B, 141 C, and 141 D between substrate 110 and diodes 140 B, 140 C, and 140 D, respectively. That is, in wafer 200 , differences in voltage potential do not increase along series-connected diodes as one approaches the terminal diode as they do in wafer 100 of FIG. 1 . As such, embodiments of the invention permit the use of higher voltage devices and/or a larger number of devices connected in series, and therefore a higher total voltage, without degrading the breakdown voltage of the series-connected device or the loss of voltage through leakage.
The voltages of individual devices (e.g., diodes 140 A-D) as well as the total voltage of the series-connected devices will depend, for example, on their application and the number of devices so connected. In some embodiments, voltages of individual devices are between about 10 V and about 50 V and total voltages are between about 20 V and about 150 V. Such voltages are exemplary, however, and are not limiting of the scope of the various embodiments of the invention.
In some embodiments of the invention, an end 153 A of n-doped band 152 A extends laterally beyond an end 143 A of diode 140 A, providing an overlap portion 154 A. Such an arrangement helps control an electric field induced by diode 140 and ensures that substrate 110 does not act to gate diode 140 A.
Similarly, in some embodiments of the invention, a space 156 A remains between adjacent n-doped bands 152 A, 152 B. That is, a second end 155 A of n-doped band 152 A is separated within substrate 110 from a first end 153 B of n-doped band 152 B. Space 156 A is large enough to ensure that n-doped band 152 A and n-doped band 152 B do not act as a single shield, which would cause the depletion regions of each diode 140 A, 140 B to intersect, resulting in a single voltage potential for the two diodes 140 A, 140 B.
FIG. 3 shows an integrated circuit 300 according to another embodiment of the invention. Here, a plurality of deep diodes 240 A- 240 D are connected in series within a thick semiconductor layer 230 . Each deep diode (e.g., 240 A) includes stacked p-doped regions 242 A, 246 A and stacked n-doped regions 244 A, 248 A, such that a shallow trench isolation 260 A and deep trench isolation 262 A are formed in semiconductor layer 230 adjacent each deep diode. Thick semiconductor layer 230 permits the incorporation of an internal isolation 247 A within deep diode 240 A. That is, internal isolation 247 A isolates p-doped region 246 A from n-doped region 248 A but does not extend through to BOX layer 220 .
FIG. 4 shows an integrated circuit 400 according to another embodiment of the invention, in which a p-doped band 352 A is used in an n-type substrate. The shielding properties of wafer 400 are similar, therefore, to those of wafer 200 in FIG. 2 .
FIG. 5 shows an integrated circuit 500 according to yet another embodiment of the invention. In wafer 500 , a plurality of high-voltage n-type field effect transistors (n-FETs) are connected in series. (For the sake of clarity, FIG. 5 shows only two n-FETs 440 A, 440 B, although any number of such devices may be connected in series, and only the features of n-FET 440 A are labeled.) Each n-FET 440 A, 440 B includes a polysilicon gate 480 A, polysilicon conductors 446 A, 448 A, a p-well 470 A, n-wells 442 A, 444 A, and a gate oxide formed from shallow trench isolation (STI) 460 A. In wafer 500 , n-doped band 452 A shields n-FET 440 A similarly to the shielding of diode 140 A in FIG. 2 .
FIG. 6 shows an integrated circuit 600 according to still another embodiment of the invention. Wafer 600 is similar to wafer 200 of FIG. 2 , but each n-doped band 652 A, 652 B, 652 C, 652 D is biased to a voltage V 1 , V 2 , V 3 , V 4 , respectively. Each voltage V 1 , V 2 , V 3 , V 4 is optimized to reduce voltage leakage or increase breakdown voltage (V br ) of its respective diode 640 A, 640 B, 640 C, 640 D.
The foregoing description of various aspects of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously, many modifications and variations are possible. Such modifications and variations that may be apparent to a person skilled in the art are intended to be included within the scope of the invention as defined by the accompanying claims. | Integrated circuits having doped bands in a substrate and beneath high-voltage semiconductor-on-insulator (SOI) devices are provided. In one embodiment, the invention provides an integrated circuit comprising: a semiconductor-on-insulator (SOI) wafer including: a substrate; a buried oxide (BOX) layer atop the substrate; and a semiconductor layer atop the BOX layer; a plurality of high voltage (HV) devices connected in series within the semiconductor layer; a doped band within the substrate and below a first of the plurality of HV devices; and a contact extending from the semiconductor layer and through the BOX layer to the doped band. | 7 |
FIELD OF INVENTION
This invention relates to reclaiming processes and more particularly to the process of removing resin from waste spun fiberglass.
BACKGROUND OF INVENTION
Resin treated spun fiberglass has been used for many different processes including the manufacture of products such as air filters of the type used in heating and air conditioning systems. A certain amount of scrap results in the manufacturing process from faulty units, mill ends and the like. Since the spun fiberglass has been treated with resin with no way until now to remove the same, waste products have been disposed of generally in landfill type environments. Since untreated chopped fiberglass sells for around $0.91 a pound on today's market, the waste products that are being disposed of amount to a loss of thousands of dollars a day throughout the industry.
Another problem being encountered is that the resin, which is usually urea-formaldehyde type, breaks down and leaches out into the soil contaminating surrounding surface and underground water sources. Thus the loss is not simply the value of the waste product but also the cost involved in disposing of the same.
BRIEF DESCRIPTION OF INVENTION
After much research and study into the above-mentioned problems, the present invention has been developed to provide a method to remove the resin from resin treated spun fiberglass of either the continuous or chopped fiber type. This process not only returns virtually one hundred percent of the fiberglass treated to a useable condition, but it also eliminates the cost of disposal as well as the resultant pollution control problems associated therewith.
The above is accomplished by passing the product through a treatment tank and then rinsing any residue therefrom prior to drying, chopping, and recycling into the marketplace. This process is relatively inexpensive and yet is highly efficient in the use. It can be adapted to all types of ureaformaldehyde type resin coated fiberglass.
In view of the above, it is an object of the present invention to provide a means for removing resin from resin treated spun fiber-glass.
Another object of the present invention is to provide a simple, relatively inexpensive, and yet highly efficient means for removing resin from treated fiberglass.
Another object of the present invention is to provide means for removing urea-formaldehyde type resin from either continuous or chopped spun fiberglass.
Another object of the present invention is to provide a means for reclaiming waste resin treated fiberglass.
Other objects and advantages of the present invention will become apparent and obvious from a study of the following description and the accompanying drawing which are merely illustrative of such invention.
BRIEF DESCRIPTION OF DRAWING
The drawing is a schematic illustration of the reclaiming process of the present invention.
DETAILED DESCRIPTION OF INVENTION
With further reference to the drawing, the waste product 11 such as urea-formaldehyde resin coated continuous or chopped spun fiberglass is conveyed or otherwise moved into treatment tank 12 containing a mixture of between ten percent and fifty percent phosphoric acid (H 3 PO 4 ) to water (H 2 O) which has been heated to approximately 200 degrees Fahrenheit. The waste product is allowed to remain in the treatment tank between five and thirty seconds or until the resin has been removed from the fiberglass fibers. The product is then removed from the treatment tank and rinsed with water (H 2 O) at two distinct stages as indicated at 13 and 14. This rinsing can be either by spray, emersion or a combination of the two.
Next the product being reclaimed is dried as indicated at 15 through use of forced air heated to between 80 and 90 degrees Fahrenheit. Next the resin free fibers are chopped as indicated at 16 into commercially useable length of approximately one-quarter inch. The thus reclaimed product is removed from the system at 17.
Since the form of the waste product being put into the system of the present invention varies from loose fiber clumps to baled concentrations to other forms, the means of conveying such products from input to output also varies substantially mechanically. The steps of the process of treatment, however, would remain the same.
Likewise, the method of rinsing and the specific equipment for chopping the fibers can vary mechanically but such devices are well known to those skilled in the art and further detailed discussion of the same is not deemed necessary.
From the above, it can be seen that the process of the present invention takes a presently useless product which manufacturers not only lose but have to pay for disposal of and makes the same into a sellable, commercially useable product selling for as much as $1.00 per pound at 1980 wholesale prices. This process is relatively inexpensive and yet is highly efficient in accomplishing the results desired.
The present invention may, of course, be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive and all changes coming within the meaning and equivalency range of the appended Claims are intended to be embraced therein. | A coating of urea-formaldehyde resin is removed from spun fiberglass with an aqueous phosphoric acid solution. The fiberglass product is subsequently rinsed, dried and chopped for reuse. | 2 |
BACKGROUND OF THE INVENTION
Electrodes which are used to record biopotentials from the surface of the skin generally require the use of a conductive liquid or solid gel to provide a continuous conductive path between the recording surface (i.e., the skin) and the electrode sensing element. Conductive gels contain a salt (KCl or NaCl) in order to achieve electrical current flow. The preferred gel is one with a high salt content, since such a gel produces a better conductor than that obtained when using a gel with a low salt content. In addition, the use of a high salt content gel typically requires less skin abrasion at the time of application to reduce the impedance of the skin-electrode interface after subsequent electrode application.
For ease of use, it is desirable to apply the conductive liquid or solid gel at the point of manufacture, creating a “pre-gelled” electrode. U.S. Pat. No. 4,559,950 issued to Vaughn and U.S. Pat. No. 5,309,909 issued to Gadsby describe two such electrodes. Use of such electrodes saves the user the step of manually applying the gel to the electrode at the time of electrode application and speeds the application process considerably. Thus, the ideal electrode would be one pre-gelled with high salt content conductive gel. Such an electrode would minimize application time by reducing the amount of skin “prepping” (abrasion) required by low salt content gels and eliminating the step of dispensing the gel onto the electrode surface.
Numerous prior art references exist that show that one can make a pregelled electrode by chloriding the surface of a silver substrate to create a Ag/AgCl electrode element with a stable half cell potential. Often, a silver-plated plastic substrate is used instead of solid silver, for cost reasons. An electrolytic gel may then be applied at the time of manufacture to create a pre-gelled electrode.
It is common in the art to construct single-piece sensors which incorporate multiple electrode elements on a single substrate. Such sensors have the advantages of low cost, ease of use, and precise positioning of the electrode elements. A common method of construction, as described in U.S. Pat. No. 5,337,748 issued to McAdams, utilizes a flexible circuit, created by printing a circuit on a plastic substrate using conductive ink. The conductive ink makes up the electrode sensing element and provides an electrical connection between the individual electrode elements and a cable connector, which facilitates connection to a data acquisition system. The conductive ink generally consists of flakes of silver (Ag) in a liquid binder. U.S. Pat. No. 4,852,572 issued to Nakahashi describes a pregelled, multiple electrode sensor constructed by printing a single layer of conductive ink on a non-woven cloth substrate. It is not possible, however, to pre-gel sensors constructed using conductive inks with liquid conductive gels because the salt content of the liquid gel quickly reacts with the Ag flakes in the ink and renders the circuit non-conductive. Such a process would lead to early sensor failure and a reduced shelf life. For this reason, sensors constructed using conductive inks are pre-gelled using a cured solid hydrogel with a low salt concentration. The use of a low salt content gel slows the rate at which the salt content of the gel corrodes the Ag element and therefore extends product shelf life. The impedance of the skin-electrode interface is generally higher than that which could be achieved with a high salt content gel, and the resultant electrical signal is much noisier. In addition, vigorous skin prepping is required to lower the impedance to an acceptable level, due to the limited hydrating properties of a solid gel.
Various prior art constructions exist which use multiple layers of conductive inks for low fidelity applications, such as the acquisition of resting EKG signals. One such construction is the TCP-3208 conductive coated polyester manufactured by Tolas Healthcare Packaging which includes a layer of conductive carbon material underneath a layer of conductive Ag/AgCl. The main purpose of this construction is to minimize the amount of silver (Ag) on a circuit trace, thus reducing the manufacturing cost. Such a construction generally makes use of solid hydrogel as the ionic interfacing material.
Another prior art construction, which is described in U.S. Pat. No. 5,337,748 issued to McAdams includes a single layer of Ag or Ag/AgCl ink on a flexible substrate such as vinyl or Melinex to make an electrode. Again, a solid hydrogel or a low concentration of salt in the liquid gel must be used in order to obtain an acceptable shelf life. Carrier in U.S. Pat. No. 5,352,315, teaches the use of a single conductive ink layer of either Ag/AgCl or a homogenous mixture of Ag/AgCl and carbon inks printed on a nonconductive backing layer.
U.S. Pat. No. 4,787,390 issued to Takata teaches the use of snap and eyelet type construction, though in this case the snap and eyelet is simply used to make mechanical contact between different components of the electrode and not to provide a pressure-sealed gel isolation function. U.S. Pat. No. 4,444,194 issued to Burcham and U.S. Pat. No. 4,617,935 issued to Cartmell also teach the use of a snap and eyelet construction, but only for the purpose of physically connecting electrode components.
It is therefore a principal object of the present invention to provide an electrophysiological electrode that utilizes a flexible circuit construction while allowing for the use of high salt content liquid electrolytic gels.
Another object of the present invention is to provide an electrophysiological electrode that contains a single interfacing contact to an electrophysiological monitor or other data acquisition system.
It is a further object of the present invention to provide an electrophysiological electrode with pre-gelled electrodes which provide low impedance while reducing the need for skin preparation.
SUMMARY OF THE INVENTION
This invention is an electrophysiological electrode that includes multiple layers of materials to isolate liquid electrolytic gels from the conductive inks on the flexible circuit of the electrode substrate. Such an electrode has a much longer shelf life under normal storage conditions than other electrodes of such construction with high salt content liquid electrolytic gel, and is able to maintain acceptable impedance upon its eventual use.
These and other objects and features of the present invention will be more fully understood from the following detailed description which should be read in light of the accompanying drawings in which corresponding reference numerals refer to corresponding parts throughout the several views.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a preferred embodiment of an electrode of the present invention which uses a snap and eyelet assembly press fit onto a flexible circuit for electrical contact and a foam material for liquid seal.
FIG. 2 ( a ) is a top plan view of a sensor incorporating the electrodes shown in FIG. 1 .
FIG. 2 ( b ) is a side elevational view of the sensor shown in FIG. 2 ( a ) which shows the snap and eyelet function of making electrical contact and liquid sealing.
FIG. 3 is an exploded perspective view of the embodiment of a sensor of the present invention shown in FIGS. 1, 2 ( a ) and 2 ( b ) in which the foam materials are partially cut away.
FIG. 4 is an exploded perspective view of another preferred embodiment of the present invention which uses two passes of ink and an electrolytic gel over the ink.
FIG. 5 ( a ) is a top plan view of an alternate embodiment of a sensor of the present invention in which a Ag/AgCl screen is printed over Ag ink on a flexible substrate.
FIG. 5 ( b ) is a side elevational view of the sensor shown in FIG. 4 .
FIG. 6 is an exploded perspective view of another preferred embodiment of the electrode of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1-3, a preferred embodiment of an electrode 10 of the present invention is shown which makes use of a conductive Ag/AgCl-plated ABS (acrylo-nitrile butadiene styrene) plastic eyelet 12 attached to a flexible polyester substrate 14 by means of a pressure-fitted non-conductive plastic snap 16 . A conductive trace 13 is printed on the underside of the flexible substrate 14 with Ag conductive ink such as Dupont 5000 screen printable ink, producing a flexible circuit 15 . This flexible circuit makes electrical contact with the eyelet 12 at the eyelet shoulder 18 . The bottom 20 of the eyelet 12 is in contact with the liquid gel 39 (see FIG. 2 ( b )). The eyelet bottom 20 is physically isolated from its shoulder 18 by a layer of foam 22 with a punched hole for the eyelet shoulder 18 and top 24 to pass through. The foam 22 prevents the liquid gel from coming into contact with the conductive Ag ink of the flexible circuit. In the preferred embodiment, the foam is {fraction (1/32)}″ thick double-sided adhesive-backed polyethylene foam, an example of which is sold by MACTAC. The preferred diameter of the punched foam hole is 0.050″ larger than the shoulder diameter. The preferred eyelet shoulder diameter is 0.22″ and the preferred foam hole diameter is 0.27 inches.
In a preferred embodiment shown in FIG. 2, the snap and eyelet assembly is integrated into a multiple electrode element sensor 30 . FIG. 2 also more clearly shows the additional components of a multiple element sensor constructed using multiple snap and eyelet electrode assemblies 10 .
In the preferred embodiment shown in FIG. 2 ( b ), the plastic snap 16 is pressed down over the top of the eyelet 12 , sandwiching the flexible circuit 15 and the foam seal layer 22 between the eyelet 12 and the snap 16 . A basepad layer 32 of {fraction (1/16)}″ double-sided adhesive foam is placed below the foam seal layer 22 . As shown most clearly in FIG. 3, the top side of the basepad layer 32 (shown with a portion cut away) adheres firmly to the from of the seal layer 22 and it contains a circular hole of 0.6″ diameter concentric to the eyelet creating a cylindrical housing to contain the liquid gel. The foam of the basepad layer 32 is made of the same foam as that of the seal layer 22 .
The preferred embodiment utilizes a studded, porous spacer made of a disc 34 , 0.6 inches in diameter, stamped out of Velcro hook material. The hook material has been sheared to make tines that will serve as a skin prepping mechanism when the user presses against them during use, in the same manner as described in U.S. Pat. No. 5,305,746 issued to Fendrock and assigned to the assignee of the present application. The backing 36 of the Velcro material is porous. The preferred Velcro thickness (including backing and tine profile) is approximately 0.08 inches. The liquid gel 39 is held in the gel pocket by a porous sponge 38 , which is a urethane open pore sponge in the preferred embodiment.
The pressure exerted by the snap fit between the snap 16 and the eyelet 12 provides constant electrical contact between the eyelet 12 and the conductive trace 13 of the flexible printed circuit 15 at the shoulder 18 of the eyelet 12 .
The pressure fit assembly also sandwiches the foam seal layer 22 between the snap 16 and the eyelet 12 . This gaskets the top area of the eyelet and produces a tight seal which keeps the liquid gel 39 from contacting the flexible circuit 15 . As a result, the gel is confined to the gel pocket below the bottom surface of the eyelet 12 and is not allowed to come in contact with the conductive Ag ink on the flexible circuit. The preferred conductive liquid gel is 10% salt content liquid hydrogel.
The flexible circuit 15 is connected to a cable connector 40 , which allows connection of the electrode to a data acquisition system (not shown).
Another embodiment which accomplishes the goal of isolating the conductive Ag ink from the high salt content conductive gel is shown in FIGS. 4, 5 ( a ) and 5 ( b ). In this alternate embodiment, a flexible circuit 50 is created by printing a layer of conductive Ag ink 52 on a flexible plastic substrate (Mylar) 54 . Isolation of the Ag conductor from the gel is accomplished by printing an eyelet layer 56 of Ag/AgCl ink (Acheson 7019™ in the preferred embodiment) over the conductive Ag ink 52 . The eyelet layer 56 serves the same function as the eyelet 12 in the snap and eyelet embodiment shown in FIG. 1 .
A basepad 58 (shown with a portion cut away) of {fraction (1/16)}″ double-sided adhesive foam with a circular hole of 0.6″ diameter, is placed onto the plastic substrate 54 so that the hole is centered concentric to the eyelet. This hole in the basepad 58 creates a cylindrical housing which is used to contain the liquid gel. Additionally, there is a studded, porous spacer disc 60 , 0.6 inches in diameter, stamped out of Velcro hook material. The hooks 62 on the disc 60 have been sheared to make tines that will serve as a skin prepping mechanism when the user presses against them during use. The backing of the disc 60 is porous to allow the gel to go through it and provides full conductivity in the direction perpendicular to the electrode substrate. The preferred Velcro thickness including the tine profile is approximately 0.08 inches. The liquid gel is held in the cylindrical housing by a porous spacer sponge 66 made out of urethane porous material which is impregnated with the liquid gel.
The flexible printed conductive circuit 50 electrically connects the electrode element to a cable connector 40 (FIG. 5 ( a )). The cable connector allows connection of the sensor to a data acquisition system.
Placing a layer of chlorided material over the non-chlorided conductive material as described above provides the following benefits over prior art:
The Ag/AgCl surface serves the same purpose of the eyelet in the embodiment shown in FIG. 1, electrically interfacing to the conductive gel. It also provides a limited isolation of the conductive Ag layer from the corrosive effects of the conductive gel. The isolation is limited because the screen printing process creates a porous Ag/AgCl surface that is not completely impermeable.
Because AgCl is not initially present in the bottom layer, any increase in AgCl in the Ag layer resulting from chloriding reactions which occur between the conductive gel and the metal (Ag) flakes in the conductive ink will cause the concentration of AgCl in the Ag layer to increase from zero rather than from an initial concentration greater than zero. This extends the life of the product by providing more Ag flakes at the start which translates to more conductive paths.
In addition, because there are no large molecules of AgCl in the underlying conductive layer, the Ag flakes are closely bound together and prevent the electrolyte from penetrating any large gaps left unfilled by the binding substrate of the ink. This slows down the chloriding process. In addition, the Ag flakes are closely bound together and thus maintain a higher conductivity than a Ag/AgCl ink. This translates to less noise overall during data collection.
Other alternate embodiments utilize carbon, nickel, copper or other metal inks on the bottom layer instead of silver for electrodes that do not require high noise sensitivity.
Another alternate embodiment utilizes solid instead of liquid hydrogels. While solid hydrogels have lower conductivities than liquid gels, their use can be advantageous for sensors which incorporate closely-spaced multiple electrode sensors. In such an application, the higher material crosslinking of the solid hydrogel prevents shorting of the electrode elements due to gel migration, which would occur if liquid gels were used. This embodiment allows the use of solid hydrogels with higher salt content than is commonly used while still achieving the same intent to maximize shelf life.
The embodiment of the electrode of the present invention shown in FIG. 6 utilizes a layer of solid hydrogel 70 as a barrier layer between the conductive ink 52 and the liquid gel impregnated in the sponge 66 . This construction uses an Ag/AgCl conductive ink and the layer of solid hydrogel 70 acts as an exchange barrier between the conductive ink 52 and the liquid gel.
While the foregoing invention has been described with reference to its preferred embodiments, various alterations and modifications will occur to those skilled in the art. For example, while various dimensions are recited above for components of the present invention, it should be understood that these are simply the preferred dimensions and that differently sized components could be used and different number of electrodes could be incorporated on a sensor and still achieve the intended results. These and all other such alterations and modifications are intended to fall within the scope of the appended claims. | An electrophysiological electrode includes multiple layers of materials to isolate liquid electrolytic gels from the conductive inks on the flexible circuit of the electrode substrate. Such an electrode has a much longer shelf life under normal storage conditions than other electrodes of such construction with high salt content liquid electrolytic gel, and is able to maintain acceptable impedance upon its eventual use. | 0 |
BACKGROUND OF THE INVENTION
Unsaturated ester compounds, such as unsaturated alkyd resins, particularly the esters of acrylic or methacrylic acid, respectively, and especially the acrylates or methacrylates of poly-functional alcohols, are polymerized by means of substances supplying free radicals, particularly by means of organic peroxides.
The radicals introducing this polymerization of the olefinically unsaturated compounds can also develop by means of ultraviolet radiation in combination with so-called ultraviolet initiators or sensitizers when the unsaturated substances to be polymerized contain such initiators and are then subjected to an intensive radiation by means of ultraviolet light. Benzoin or its ether derivatives, respectively, have been used for a long time as particularly suitable ultraviolet initiators for the unsaturated polyester substances. Photopolymerizable dental substances for tooth fillings consisting of a mixture of polyacrylates and acrylic ester monomers and containing benzoin as photoinitiator are described in the British Pat. No. 569,974 (1945). These substances are hardened by means of ultraviolet radiation in the mouth. However, in practice it has been found that the required periods of time for the radiation necessary to achieve polymerization were too long and, therefore, this procedure was not considered of great importance at that time.
The photo-hardening of substances containing poly-functional acrylic esters is also utilized in other fields. Thus, printing ink or finishing varnish are described in the British Pat. No. 1,198,259 which contain benzoin ethyl ether as ultraviolet initiator and are hardened by means of ultraviolet radiation. Polymer compositions are described in German Offenlegungschrift No. 23, 15, 645 which consist of reaction products of organic isocyanates and hydroxyalkylacrylate and contain unsaturated monomers, such as alkylacrylate or alkylmethacrylate. These substances contain also benzoinalkylether and can be hardened by radiation. In the same way, similar substances are described in the German Offenlegungschrift No. 23, 20, 038 which are utilized in dentistry.
Since unsaturated polyesters often become unstable and tend towards a premature polymerization when the very sensitive polymerization initiators are added so that these substances have then only a short storage time, stabilizers are added to them, e.g. phenolic compounds such as hydroquinone or methoxyphenol. Also organic phosphites, e.g. trimethylphosphite or triphenylphosphite, are disclosed in German Offenlegungschrift No. 19, 34, 637, together with a cuprous salt of an organic acid, for the stabilization of unsaturated polyester substances containing benzoin or its derivatives whereby the phosphite stabilizer should be present in an amount of 200-800 ppm. Ultraviolet-hardenable coloring, impregnating, coating or priming substances based on unsaturated polyesters are described in German Offenlegungschrift No. 21, 04, 958 which contain, besides benzoin ether, also organic esters of the phosphorous acid and organic derivatives of phosphine. In this way, a good storage stability is achieved with a short polymerization speed at the hardening by means of ultraviolet radiation. The utilization of esters of phosphorous acid, e.g., triphenylphosphite, is also described in the German Auslengungschrift No. 10, 98, 712 as an additive to increase the storage and color stability of unsaturated polyester resin substances.
The ultraviolet-initiated hardening of tooth filling substances as well as the sealing of teeth by means of such coating substances has met with great interest in the field of dentistry in the past years. However, so far, either very intensive radiation units must be utilized or long periods of radiation are required in order to obtain a complete hardening. Furthermore, these preparations cannot contain any additives which could effect a discoloring of the polymerized substance after some time under the influence of the environment in the mouth, particularly of the different types of food and liquids. Consequently, the organic phosphine compounds made known, for example, as catalysts of the benzoin-initiated ultraviolet polymerization in the case of the unsaturated polyester substances of German Offenlegungschrift No. 21, 04, 958 cannot be used with dental substances based on acrylic or methacrylic esters because these phosphine compounds lead to a discoloring of the tooth fillings or sealings after a period of time.
SUMMARY OF THE INVENTION
It has now surprisingly been determined that the polymerization of acrylic ester substances, particularly of acrylic or methacrylic esters of poly-functional alcohol compounds, effected by means of benzoin ether and similar ultraviolet initiators can be accelerated by two to ten times by the presence of organic phosphite compounds alone if these organic phosphite compounds are present in a concentration of 0.1 to 20% based on the amount of the ester component. This increase in the sensitivity of the polymerizable acrylic or methacrylic ester substances vis-a-vis ultraviolet radiation is particularly surprising because, according to the status of the art, i.e., in the already mentioned German Offenlegungschrift 19, 34, 637 or in the German Auslegeschrift No. 10, 98, 712, these organic phosphite compounds are added there as stabilizers to prevent premature polymerization of the unsaturated ester substances used therein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The aliphatic or aromatic phosphites used as activator for the benzoin-ether-initiated ultraviolet polymerization are preferably utilized in a concentration of 0.1 to 20, preferably 0.1 to 2, most preferably 0.2 to 1, percent by weight based on the amount of the acrylic or methacrylic ester compounds to be polymerized. The benzoin derivatives present as initiators for the ultraviolet polymerization may be present in the customary concentrations, i.e., in an amount of 0.1 to 5%, preferably 0.2 to 2%. Generally, the optimum concentration of the benzoin derivative is 0.2 to 1% (by weight) benzoin derivative, based on the amount of the ester compounds to be polymerized.
The activating organic phosphites can have solely aliphatic or solely aromatic substituents and may also contain both aliphatic and aromatic substituents in the same phosphite compound. In contrast to the system claimed in the German Offenlegungschrift No. 21, 04, 958 in which one of the substituents of the phosphite compound, which is linked to the phosphorus through oxygen, must be aromatic, the phosphites utilized in the present invention may consist of purely aliphatic phosphites. Also, secondary phosphites are very useful, independently of whether the substituents linked to phosphorus through oxygen are aliphatic or aromatic. Examples for the phosphites to be used as activators according to the invention are listed as follows: Dimethyl-phosphite, dioctyl-phosphite, diphenyl-phosphite, tri-i-octyl-phosphite, tri-stearyl-phosphite, trimethyl-phosphite, tri-ethyl-phosphite, tri-i-propyl-phosphite, tris-allyl-phosphite, didecyl-phenyl-phosphite, tri-phenyl-phosphite, tris-4-nonylphenyl-phosphite and tris-4-chlorophenyl-phosphite.
As ultraviolet initiators, benzoin or its derivatives can be used with the substances activated according to the invention, for example, benzoin-methylether, benzoin-ethylether, benzoin-i-propylether, benzoin-butylether, benzoin-trimethylsilylether, α-methylbenzoin, α-methyl-benzoin-methylether, α-methyl-benzoin-trimethylsilylether, α-(2-methoxy-carbonyl-ethyl)-benzoinmethylether, α-(2-cyanethyl)-benzoinmethylether or α-(2-carboxyethyl)-benzoinmethylether.
In this present invention, monomeric acrylates or methacrylates, are utilized as ultraviolet-polymerizable compounds, and in particular the di- or tri-functional acrylic acid or methacrylic acid derivatives which harden to form cross-linked polymers as disclosed, for example, in U.S. Pat. No. 3,066,112 or German Pat. No. 1,921,869. Also, mixtures of these ester compounds can now be easily and rapidly copolymerized and hardened by means of radiation. Examples of methacrylic ester compounds preferably used in the field of dentistry are: 2,2-bis-[p-(α-hydroxy-propoxy-)phenyl]-propane-dimethacrylate (Dimethacrylate I), 2,2,-bis-[p-(β-hydroxy-propoxy-)phenyl]-propane-dimethacrylate (Dimethacrylate II), the reaction product of bisphenol with glycidylmethacrylate (Dimethacrylate III), butandiol-1.4-dimethacrylate, and trimethylolpropanetrimethacrylate.
The essential acceleration of the polymerization and thus of the hardening of the acrylate compounds, particularly of the poly-functional methacrylates mostly used in these compositions, is achieved by means of the new combination of organic phosphites and benzoin derivatives as initiators of the polymerization by radiation with ultraviolet light. With the use of particularly suitable combinations of phosphite and benzoin derivatives, the duration of the polymerization can be shortened by a power of ten with the same radiation intensity and other reaction conditions in comparison with a corresponding substance which, besides the usual additives such as fillers, etc., contains only the respective benzoin derivatives. In this manner, the necessary duration of the radiation can be very much shortened or the desred hardening can be achieved with ultraviolet radiating systems which are simpler and can be built more easily and also require less energy.
The polymerizable substances activated according to the invention can contain the usual fillers although the fillers which can be used should, if possible, be those fillers which practically do not adsorb or adsorb comparatively little ultraviolet light. Pulverized quartz and particularly also barium silicate glasses as well as pulverized polyacrylate are especially suitable. Also quartz or glass fibers can be suitably used as fillers.
Also, the compositions should contain customarily utilized inhibitors to prevent premature, unwanted polymerization of the hardenable substances in order to obtain ready preparations which are stable for storage purposes. Hydroquinone, ionol, methoxyphenol and other conventional inhibitors are suitable in this instance.
The present invention is particularly useful in the field of dentistry because quick hardening is especially desirable. The polymerizable acrylate and methacrylate-based compounds are suitable as tooth fillers as well as coatings for the sealing of teeth or as fixing preparations, particularly for orthodontics. However, it is quite obvious to one skilled in the art that the advantages of the rapid acceleration of polymerization is also of great economic importance in other technical fields where these acrylic or methacrylic ester substances are hardened by ultraviolet radiation, for example, when used as binding agent for printing ink, film coatings on all kinds of objects, etc.
In order to initiate the polymerization, it is sufficient to use the natural sun light as radiation source in view of the increased radiation sensitivity of the combination according to the present invention. However, depending on the field of application, special ultraviolet lamps will preferably be utilized, the emission of which should be within the range from 200 to 400 nm, particularly within the range from 320 to 400 nm, as this is also the case of the known ultraviolet polymerizations which are benzoin-activated.
The invention is additionally illustrated in connection with the following Examples which are to be considered as illustrative of the present invention. It should be understood, however, that the invention is not limited to the specific details of the Examples.
EXAMPLES
Photopolymerization was effected, in each of the Examples, in the following manner:
A white plastic ring with an inner diameter of 7 mm and a height of 2 mm, which is placed on a cover glass of an object support, is filled to its edge without forming bubbles with an ultraviolet-polymerizable compound containing benzoin and/or an α-C and/or O-substituted benzoin derivative as ultraviolet sensitizer or a mixture of one of the mentioned benzoins and one of the listed phosphorous acid esters or with a mixture of a filler (for example, quartz, Li-Al-silicates, Ba-silicates) and an ultraviolet-polymerizable compound which contains one of the mentioned benzoin derivatives or a mixture of one of the mentioned benzoin derivatives and one of the listed phosphorous acid esters and is then covered up with a cover glass of an object support. The specific compositions tested are described below in the Examples. In each instance, the percents by weight of the phosphite compound and the benzoin compound are based on the weight of the ultraviolet polymerizable acrylic or methacrylic ester utilized. A Nuva-Lite (Hg high-pressure lamp made by Caulk) served in each case as the source of light for the photo-polymerization which lamp emits light of the wave length λ > 350 nm, preferably λ = 366 nm.
The flat end of the quartz rod of the Nuva-Lite serving as light conductor is placed centrally and planely on the upper glass on the object support for the polymerization and the closed-in ultraviolet-polymerizable substance is polymerized from one side through the cover glass. Polymerization time, t 2 (sec.), as used herein is that time after which, when the cover glasses were removed, the rear of the 2 mm thick layer did not permit penetration with a probe at a bearing pressure of 100 g.
EXAMPLE 1
In accordance with the above-described method, the polymerization time t 2 (sec.) of Dimethacrylate I (2,2-bis-[p-(γ-hydroxy-propoxy-)phenyl]-propane-dimethacrylate), which was stabilized by means of 200 ppm p-methoxy-phenol and 200 ppm ionol and contained 2.0 percent by weight to 4 percent by weight benzoinmethylether as sensitizer, was determined in the absence of an organic phosphite as well as in the presence of 5 percent by weight tris-4-nonyl-phenyl-phosphite.
______________________________________ t.sub.2 (sec.)Percent by weight without 5 percent by weight tris-Benzoin-methylether phosphite 4-nonyl-phenyl-phosphite______________________________________2.0 22 114.0 54 26______________________________________
It may be seen that the addition of the phosphite compound substantially reduced the polymerization time of the composition.
EXAMPLES 2 to 7
Similar to Example 1, the polymerization times t 2 (sec.) of the ultraviolet polymerization, sensitized by amounts of 0.5 percent by weight benzoin-methylether, of Dimethacrylate I were measured in the presence of different organic phosphites in amounts of 5 percent by weight.
______________________________________Ex. Phosphite t.sub.2 (sec.)______________________________________without phosphite 92 tri-phenyl-phosphite 5 percent by weight 33 di-decyl-phenyl-phosphite " 44 tris-allyl-phosphite " 35 tris-i-propyl-phosphite " 56 tri-ethyl-phosphite " 37 tri-methyl-phosphite " 3______________________________________
Again, the addition of each of the phosphite compounds substantially reduced the polymerization time of the composition.
EXAMPLES 8 to 15
In accordance with the general procedure as explained above, the polymerization times t 2 (sec.) of ultraviolet polymerization of Dimethacrylate I, sensitized by amounts of 0.5 percent by weight of different benzoin derivatives, were determined in the presence of 5 percent by weight di-decyl-phenyl-phosphite.
______________________________________ t.sub.2 (sec.) with 5 percent by weight di- Benzoin derivative without decyl-phenyl-Example 0.5 percent by weight phosphite phosphite______________________________________ 8 Benzoin 20 3 9 Benzoin-ethylether 10 410 Benzoin-i-propylether 10 411 Benzoin-butylether 18 412 Benzoin-trimethyl- 11 3 silylether13 α-methyl-benzoin 18 414 α-methyl-benzoin-tri- 17 5 methylether15 α-methyl-benzoin- 15 3 methylether______________________________________
It will again be noted that the addition of the phosphite compound substantially reduced the polymerization time of the compositions including the varying benzoin compounds.
EXAMPLE 16 to 23
The Examples 16 to 23 describe ultraviolet polymerization of Dimethacrylate I in the presence of 5% triethyl-phosphite in each case which compositions were sensitized in each case by 0.5 percent by weight of one of the mentioned benzoin derivatives. The percent by weight refers to the ultraviolet-polymerizable compound. The polymerization time t 2 (sec.) was determined as a comparison figure.
______________________________________ t.sub.2 (sec.) with 5 percent Benzoin derivative without by weight tri-Example 0.5 percent by weight phosphite ethyl-phosphite______________________________________16 Benzoin 20 417 Benzoin-ethylether 10 218 Benzoin-i-propylether 10 319 Benzoin-butylether 18 420 Benzoin-trimethyl- 11 3 silylether21 α-methyl-benzoin 18 322 α-methyl-benzoin-tri- 17 4 methylsilylether23 α-methyl-benzoin- 15 3 methylether______________________________________
The improvement in polymerization times utilizing the present invention is again apparent.
EXAMPLE 24
The influence of the utilized amount of phosphite on the polymerization time t 2 of the photo-polymerization of Dimethacrylate I sensitized by 4 percent by weight of benzoin-methylether and either 1 or 5 weight percent di-decyl-phenyl-phosphite can be seen from the following Table. The determination of the polymerization times t 2 was effected in accordance with the above-described procedure.
______________________________________t.sub.2 (sec.)without 1 percent by weight of 5 percent by weight ofphosphite di-decyl-phenyl-phosphite di-decyl-phenyl-phosphite______________________________________54 25 20______________________________________
EXAMPLES 25 to 28
In accordance with the previously described general procedure, the polymerization times t 2 of the ultraviolet polymerization of dimethacrylate II (2,2-bis-[p-(β-hydroxy-propoxy-)phenyl]-propane-Dimethacrylate) sensitized by 0.5 percent by weight of benzoin-methylether were determined in the absence of an organic phosphite as well as with the use of 5 percent by weight of triethyl-phosphite. The polymerization times t 2 for the photo-polymerization of butandiol-1.4-dimethacrylate and trimethylolpropanetrimethacrylate were measured in a similar manner with the sensitizing by means of 0.5 percent by weight of different benzoin derivatives in the absence and presence of 1 percent by weight of different organo-phosphites.
__________________________________________________________________________Ultraviolet-poly- Benzoin derivativeExamplemerizable compound 0.5 percent by weight Phosphite t.sub.2 (sec.)__________________________________________________________________________Dimethylacrylate II Benzoin-methylether -- 1025 " " Tri-ethyl-phosphite 4 5 percent by weightButandiol-1.4-di- Benzoin -- 75methacrylate26 " " Tri-ethyl-phosphite 1 percent by weight 40Trimethylolpropane- Benzoin-methylether -- 18trimethacrylate27 " " Di-decyl-phenyl-phos- phite 1 percent by weight 5Trimethylolpropane- Benzoin-methylether -- 18trimethacrylate28 " " Tri-ethyl-phosphite 1 percent by weight 3__________________________________________________________________________
Again, the improvement in polymerization times using the present invention is quite apparent.
EXAMPLES 29 to 40
The accleration, according to the invention, of the polymerization of Dimethacrylate I effected by ultraviolet light can be taken from the table below with variations of benzoin derivatives and types of phosphites. The determination of the polymerization time t 2 was effected according to the procedure described in the introduction.
__________________________________________________________________________Benzoin derivativesExample(percent by weight) Phosphite(percent by weight) t.sub.2 (sec.)__________________________________________________________________________Benzoin (0.5) -- 2029 " Dioctyl-phosphite (0.5) 10α-methyl-benzoin (0.5) -- 1830 " Dioctyl-phosphite (0.5) 6Benzoin-methylether (0.5) -- 931 " Dimethyl-phosphite (0.5) 3" Diphenyl-phosphite (0.5) 5Benzoin-trimethylsilyl- -- 1132 ether (0.5)" Dimethyl-phosphite (0.5) 533 α-(2-methoxycarbonylethyl)- -- 13benzoinmethylether (3)" Dimethyl-phosphite (0.5) 5α-(2-cyanethyl)-benzoin- -- 1434 methylether (3)" Dioctyl-phosphite (0.5) 5α-(2-carboxyethyl)-benzoin- -- 1335 methylether (3)" Diphenyl-phosphite (0.5) 4Benzoin-methylether (0.5) -- 9" Tris-β-chloroethyl-phosphite (0.5) 236 " Tris-i-octyl-phosphite (0.5) 4" Tristearyl-phosphite (0.5) 4Trigonal 14* (3) -- 2537 " Di-decyl-phenyl-phosphite (0.5) 15α-(2-methoxycarbonylethyl)- -- 1338 benzoinmethylether (3)" Di-decyl-phenyl-phosphite (0.5) 5α-(2-cyanethyl)-benzoin- -- 1439 methylether (3)" Di-decyl-phenyl-phosphite (0.5) 7α-(2-carboxyethyl)-benzoin- -- 1340 methylether (3)" Di-decyl-phenyl-phosphite (0.5) 6__________________________________________________________________________ *Trigonal 14 is a 1:1 mixture of benzoin-isopropylether and benzoin-n-butylether
EXAMPLE 41
The accleration of the ultraviolet polymerization of dimethacrylate I by means of a primary phosphite can be noticed from this Example; for reasons of stability, this primary phosphite was used in the form of tetrabutyl-ammonium(TBA-)-salt.
______________________________________Benzoin derivative PhosphiteEx. (percent by weight) (percent by weight) t.sub.2 (sec.)______________________________________41 Benzoin (0.5) -- 20" Monooctylphosphite (TBA-salt) (0.5) 8______________________________________
EXAMPLES 42 to 45
Similar to the Examples 1 to 25, the polymerization time t 2 of the ultraviolet polymerization of a mixture consisting of a bi-functional methacrylic ester and an inactive inorganic filler (or filler mixture), such as quartz and/or Li-Al-silicates and/or Ba-silicates, sensitized by benzoin and/or an α-C and/or O-substituted benzoin, is also considerably shortened by adding organophosphites. In this instance, the weight of the filler can amount to many times the weight of the ultraviolet-polymerizable compound.
The polymerization times t 2 of the ultraviolet polymerization, sensitized by 1 part by weight of benzoin-methylether, of pastes consisting of 100 parts by weight of Dimethacrylate I and 400 parts by weight of quartz, in the absence and presence of different organic phosphorous acid esters in amounts of 0.4 part by weight, are given below. The indications in weight refer to the photo-polymerizable compound.
______________________________________Example Phosphite (percent by weight) t.sub.2 (sec.)______________________________________ without phosphite 2042 Tri-phenyl-phosphite (0.4) 1043 Di-decyl-phenyl-phosphite (0.4) 544 Tris-4-nonylphenyl-phosphite (0.4) 1045 Tris-4-chlorphenyl-phosphite (0.4) 4______________________________________
This Example shows that the suprising reduction in polymerization time is achieved when the composition contains substantial amounts of inert filler.
EXAMPLES 46 to 48
In these Examples, the polymerization times t 2 of the photopolymerization, sensitized by means of 0.5 percent by weight of different substituted benzoins, of mixtures of silanized and toothlike colored quartz and Dimethacrylate I, which was stabilized by means of 200 ppm p-methoxyphenol and 200 ppm ionol, were determined in accordance with the above described, general method in the absence and in the presence of 5 percent by weight of different organophosphites. The indications in weight refer to the photo-polymerizable compound.
__________________________________________________________________________Benzoin derivative QuartzExample(0.5% by weight) Phosphite 5% by weight % by weight t.sub.2 (sec.)__________________________________________________________________________ Benzoin -- 400 8046 " Tris-4-nonylphenyl- 400 9 phosphite α-methyl-benzoin -- 400 4547 " Triphenyl-phosphite 400 12 α-methyl-benzoin-tri -- 370 4648 methylsilylether " Di-decyl-phenyl-phosphite 370 7__________________________________________________________________________
EXAMPLE 49
The reduction of the polymerization time t 2 , which is observed with the photo-polymerization, sensitized by means of 0.25 part by weight of benzoin-methylether, of a mixture of 370 parts by weight of silanized and colored quartz and 100 parts by weight of Dimethacrylate I in dependence of the amount of the used di-decylphenyl-phosphite, is much more pronounced than in the case of the sensitized ultraviolet polymerization of dimethacrylate I in the absence of a filler (see Example 24). The determination of the polymerization time t 2 was effected according to the general method described above.
______________________________________ t.sub.2 (sec.) di-decyl-phenyl-phosphiteBenzoin-methyl without 1 part by 5 parts byether phosphite weight weight______________________________________0.25 part by weight 30 9 5______________________________________
EXAMPLES 50 and 51
These Examples describe the reduction of the polymerization time t 2 of two commercially available dental preparations A and B which have been sensitized with 0.5 percent by weight of benzoinmethylether by adding 5 percent by weight of didecylphenyl-phosphite according to the invention. The preparation A is available on the market under the commercial name of "Nuva Fil" and is made in accordance with German Offenslegungsschrift No. 21, 26, 419 and contains Dimethacrylate III (the reaction product of bisphenol with glycidylmethacrylate). The preparation B, which is on the market under the commercial name of "Alpha Fil", contains a methacrylic ester obtained by reaction with an aliphatic di-isocyanate according to German Offenlegungsschrift No. 23, 15, 645. The indications in weight refer to the portion of the preparation not containing a filler. The measuring of the polymerization times was effected according to the described general method.
__________________________________________________________________________ Benzoin deriv- Phosphite ative (0.5% (5% byExamplePreparation Filler by weight weight) t.sub.2 (sec.)__________________________________________________________________________A Li-Al-silicate Benzoin-methyl-(Nuva-Fil) glass ether -- 6550 " " " Di-decyl- phenyl-phos- phite 30B Ba-silicate- Benzoin-methyl-51 (Alpha-Fil) glass ether -- 65" " " Di-decyl- phenyl-phos- phite 35__________________________________________________________________________
EXAMPLES 52 and 53
In the case of those two Examples, the polymerization times t 2 (sec.) and the dark storage stabilities (days) of two mixtures consisting of 100 parts by weight each of Dimethylacrylate I (stabilized by means of 200 ppm p-methoxyphenol, 200 ppm ionol), 390 parts by weight of quartz (silanized and colored) and 1 part by weight of benzoinmethylether are compared to which the following substances had been added:
Mixture C: 0.4 part by weight of triphenyl-phosphite
Mixture D: 0.4 part by weight of triphenyl-phosphite + 0.4 part by weight of triphenyl-phosphine.
The amounts of the weights refer to ultraviolet-polymerizable compound. The determination of the polymerization time was effected in accordance with the indicated general method. In order to determine the dark storage stability, the mixtures were stored under the exclusion of light at different temperatures exposed to the air in a layer thickness of 6 mm and the penetration depth of a probe with a bearing pressure of 100 g was continuously tested. The point of time when the penetration depth amounted for the first time to 5 mm or less was considered as the commencement of the polymerization.
______________________________________ Stability in the dark (days)Ex. Mixture t.sub.2 (sec.) Room temperature 36° C 50° C______________________________________52 C 10 >60 25 1953 D 10 20 13 13______________________________________
Besides the clearly reduced dark storage stability of mixture D in comparison with mixture C, a pronounced yellow coloring was observed in the case of mixture D after a 14-day storage in water at 36° C. in the polymerized condition (effected in accordance with the indicated general method). This did not occur in the case of mixture C.
EXAMPLE 54
In this Example, the photochemical copolymerization of a mixture consisting of a bi-functional and mono-functional methacrylic ester is effected. The Dimethacrylate I (stabilized by means of 200 ppm p-methoxy-phenol and 200 ppm ionol) and methacrylic acid - methylester are mixed in a ratio by weight of 7:3 and sensitized with 0.5% benzoin in the absence as well as in the presence of 5 percent by weight of tri-ethyl-phosphite and then polymerized by means of ultraviolet light. The measuring dimension was the polymerization time t 2 which was determined in accordance with the general, described method.
With sensitizing exclusively by means of 0.5 percent by weight of benzoin, a polymerization time t 2 = 75 seconds was measured, in the case of a sensitization by means of 0.5 percent by weight of benzoin and 5 percent by weight of tri-ethyl-phosphite, a polymerization time t 2 = 35 seconds was measured.
COMPARATIVE EXAMPLE
In order to prove that the polymerization time of the ultraviolet polymerization, sensitized by means of benzoin or a benzoin derivative, of the customary unsaturated polyester resins, which do not represent acrylic esters, cannot be shortened by adding an organic phosphorous acid ester, the polymerization time t 2 of a highly reactive unsaturated polyester resin (alkyd based), containing 34 percent by weight of styrol and being commercially available under the name of "Alpolit UP 303" (Manufacturer- Hoechst AG), was determined in accordance with the described general method. The sensitization was effected by means of 0.5 percent by weight of benzoin-methylether in the absence and in the presence of 1 percent by weight of didecylphenyl-phosphite.
______________________________________ t.sub.2 (sec.) 1% by weight of dide-Benzoin-methylether without phosphite cylphenyl-phosphite______________________________________0.5% by weight 20 20______________________________________
In contrast to the Examples according to the invention, the ultraviolet polymerization cannot be influenced in the case of these polyester substances by means of the combination with phosphite.
Whether an inhibiting effect and thus an improvement of the storage stability, as it is made known in the already mentioned German Offenlegungsschrift No. 19, 34, 637 as well as German Auslegungschrift No. 1, 098, 712, is effected in the case of this substance when adding phosphite, has not been tested since the present invention concerns the opposite effect, i.e., the acceleration of the polymerization by adding phosphite.
The principles, preferred embodiments and modes of operation of the present invention have been described in the foregoing specification. The invention which is intended to be protected herein, however, is not to be construed as limited to the particular forms disclosed, since these are to be regarded as illustrative rather than restrictive. Variations and changes may be made by those skilled in the art without departing from the spirit of the invention. | An improved process for the photopolymerization of compositions including photopolymerizable acrylic or methacrylic acid esters and an initiator (e.g., a benzoin compound) is disclosed. The addition of 0.1 to 20 weight percent (based on the amount of polymerizable material) of an organic phosphite substantially reduces the polymerization time of the resulting composition. | 2 |
PRIORITY STATEMENT UNDER 35 U.S.C. §119 (E) & 37 C.F.R. §1.78
This nonprovisional application claims priority based upon the prior U.S. provisional patent application entitled, “Enhanced Sanitizer Release Polymer Composition,” application No. 60/323,573, filed Sep. 19, 2001 in the name of Jeffrey Scott Svendsen.
BACKGROUND OF THE INVENTION
1. Technical Field of the Invention
This invention relates to treated substrates containing sanitizer release polymer compositions and, more particularly, to a sanitizing towel treated with an enhanced sanitizer release polymer composition for releasing cationic sanitizers.
2. Description of Related Art
In order to control microbial growth on a surface, a sanitizing solution containing antimicrobials such as sanitizers is applied to the surface with a substrate such as a woven or nonwoven fabric. A sanitizer is a compound that reduces microbial contaminants to safe levels as determined by government Public Health requirements. Currently, the safe level is a 99.999% reduction in the bacterial count.
For the process to be effective, the sanitizing solution must maintain a certain concentration of sanitizer. A serious problem occurs when the woven or nonwoven fabric reduces the concentration of sanitizer in the sanitizing solution. For example, a nonwoven fabric is repeatedly rinsed in a sanitizing solution contained in a bucket, while sanitizing the tabletop surfaces of a restaurant. If the nonwoven fabric is diluting or reducing the effectiveness of the sanitizer in the sanitizing solution, then the tabletop surfaces are not being disinfected. This can lead to an outbreak of pathogenic enteric bacteria, such as nearly all members of the genus Salmonella or E. coli. Pathogenic enteric bacteria can cause illness, or worse death.
In the field of sanitizers, guidelines exist for the minimum concentration of sanitizer in a sanitizing solution to avoid outbreaks of pathogenic enteric bacteria. The two most common sanitizers in sanitizing solutions are quaternary ammonium compound (QAC)-based or chlorine-based sanitizers. For example, by law, QAC-based sanitizer sanitizing solutions must maintain a concentration level of 200-400 parts per million to achieve the 99.999% reduction in the bacterial count.
Structurally, QACs contain four carbon atoms linked directly to one nitrogen atom through covalent bonds and four alkyl groups. The portion attached to the nitrogen atom by an electrovalent bond may be any anion, but it is usually chloride or bromide to form the salt. The nitrogen atom with the attached alkyl groups forms the positively charged cation portion. Depending on the nature of the R groups, the anion and the number of quaternary nitrogen atoms present, the antimicrobial quaternary ammonium compounds may be classified as monoalkyltrimethyl, monoalkyldimethylbenzyl, heteroaromatic, polysubstituted quaternary, bis-quaternary, or polymeric quaternary ammonium compounds.
A QAC is an ion, that is, a molecule that carries an electric charge. More specifically, a QAC is a cation, that is, an ion that possesses a positive charge. A nonionic molecule is an ion that possesses a neutral charge. An anion is an ion that possesses a negative charge. The charge of a molecule affects that molecule's intermolecular interactions. For example, a cation is attracted to an anion, and a cation repels another cation.
When QACs are applied directly to surfaces, their effect is not long-lasting due to leaching of the compound from the surface. Therefore, frequent applications may be needed to achieve prolonged antimicrobial effects.
The existing woven and nonwoven fabrics used in conjunction with sanitizing solutions to sanitize and disinfect surfaces reduce the concentration of sanitizer in the sanitizing solution rendering the sanitizing solution ineffective. Over a short period of time and under normal use, the existing fabrics reduce the concentration of sanitizer in the sanitizing solution to less than 200 parts per million. The surfaces of woven fabrics are treated with a surfactant to achieve the surface quality desired. A surfactant is a chemical additive that changes the surface attraction between two liquids, or between a liquid and a solid, by changing the surface energy of one or both components. Woven fabrics in common use today with sanitizing solutions are made with anionic surfactants. Nonwoven fabrics are constructed of loose strands of material that are bound together with binders. A binder is an adhesive, applied with a solvent or by melting a softenable plastic, to bond fibers together in a web or one web to another. Nonwoven fabrics in common use today with sanitizing solutions are made with anionic binders and surfactants.
The negative charge of the anionic binders and surfactants utilized in substrates today attracts and bonds the cationic QAC-based sanitizer to the fabric thereby reducing and neutralizing the concentration of sanitizer in the sanitizing solution. Moreover, woven fabrics comprise many interwoven strands of material, thereby creating a large irregular surface area that captures a large number of cationic QACs during use, thereby reducing the concentration of sanitizer in the sanitizing solution. Existing methods to solve this problem are to regularly replace the sanitizing solution or regularly replenish the concentration of sanitizer. However, these existing methods are not without limitations and disadvantages.
These existing methods are time consuming and expensive. Regularly monitoring and replacing or replenishing the sanitizing solution involves considerable employee time and the expense associated with replacing or replenishing the sanitizing solution. Additionally, during busy times in many restaurants, replacement or replenishment of the sanitizing solution is often forgotten, resulting in insufficient levels of microbial reduction.
Therefore, a need has arisen for a sanitizer release polymer composition that is capable of preventing today's fabrics from bonding to the sanitizer. Further, a need has arisen for a substrate that does not bond to or neutralize the sanitizer. The present invention provides such a composition and substrate.
SUMMARY OF THE INVENTION
In one aspect, the present invention is directed to an article for sanitizing a surface utilizing a sanitizing solution that includes a sanitizer at an effective concentration level. The article includes a substrate that absorbs and holds the sanitizing solution, and a composition covering at least a portion of the substrate. The substrate may be, for example, a woven, nonwoven, or knit fabric, a foam or sponge, or other structure suitable for absorbing and holding a sanitizing solution while wiping off a surface. The substrate has a structure that enables a user to wipe the surface with the substrate, thereby applying the sanitizing solution to the surface. The composition is operable to maintain the concentration level of the sanitizer at the effective level.
In another aspect, the present invention is directed to a sanitizing towel utilized to sanitize one of a plurality of areas in a restaurant utilizing a sanitizing solution that includes a sanitizer at an effective concentration level. The sanitizing towel includes a substrate that absorbs and holds the sanitizing solution, and enables a user to apply the sanitizing solution to the surface. The substrate may be selected from the group consisting of woven fabrics, nonwoven fabrics, knit fabrics, and foams. A sanitizer release polymer composition covers at least a portion of the substrate, and is operable to maintain the concentration level of the sanitizer at the effective level. Preferably, the sanitizer release polymer composition comprises at least one cationic surfactant which, in the preferred embodiment, is present in the sanitizer release polymer composition in an amount of about 1 to about 10 weight percent, based on a total weight of the sanitizer release polymer composition. In an alternative embodiment, the sanitizer release polymer composition comprises at least one nonionic surfactant.
In yet another aspect, the present invention is directed to a method of treating a substrate utilized with a sanitizing solution to maintain a sanitizer in the sanitizing solution at an effective concentration level. The method includes the steps of selecting a substrate, selecting a cationic (or nonionic) surfactant for applying to the substrate, and applying the surfactant to the substrate. The surfactant may be a component in a sanitizer release polymer composition in which the surfactant is present in an amount of about 0.1 to about 99 weight percent, based on a total weight of the sanitizer release polymer composition. The composition may be applied to the substrate by diluting the composition with water or an organic solvent, and applying the diluted composition by dip coating, spray coating, or foam coating.
BRIEF DESCRIPTION OF THE DRAWING
The invention will be better understood and its numerous objects and advantages will become more apparent to those skilled in the art by reference to the following drawing, in conjunction with the accompanying specification, in which:
FIG. 1 is a flow chart outlining the steps of a process for manufacturing a treated substrate in accordance with the teachings of the present invention.
DETAILED DESCRIPTION OF EMBODIMENTS
Preferred embodiments of the invention will now be described with reference to various examples of how the invention can best be made and used.
The present invention provides substrate treated with an enhanced sanitizer release polymer composition. The substrate may be any suitable material that can be treated with the enhanced sanitizer release polymer composition, and that will absorb sanitizing solution for wiping and sanitizing surfaces. For example, the substrate may be a woven, nonwoven, or knit fabric, a foam or sponge-like material, or the like. The enhanced sanitizer release polymer composition contains at least one cationic or nonionic surfactant. Optionally, the enhanced sanitizer release polymer composition may contain a co-surfactant. Optionally, the enhanced sanitizer release polymer composition may contain one or more additive agents that functionally and chemically improve the bonding of the cationic surfactant and optional co-surfactant(s) to a particular substrate. Optionally, the enhanced sanitizer release polymer composition may contain one or more fillers. In an alternative embodiment, the enhanced sanitizer release polymer composition contains only nonionic surfactants.
The purpose of any finish, such as a surfactant, is to improve the aesthetic, functional or processing properties of substrates. Surfactants are a class of materials broadly characterized as being made of molecules containing hydrophilic groups adequately separated from hydrophobic groups. The hydrophobic groups have an affinity for the fiber surface. The hydrophilic groups are attached predominantly to the aqueous medium. Existing substrates used in the field of sanitizers use anionic surfactants which have the negative effect of attracting the cationic QAC-based and cationic chlorine-based sanitizers thereby reducing the concentration of sanitizer in the sanitizing solution. The enhanced sanitizer release polymer composition of the present invention achieves its unexpectedly superior sanitizer release properties by preferably using a cationic surfactant that repels the cationic QAC-based and cationic chlorine-based sanitizers and prevents the sanitizer from bonding to the substrate. This enables the substrate to be used repeatedly with the sanitizing solution without significantly reducing the concentration of sanitizer in the sanitizing solution.
As noted, the enhanced sanitizer release polymer composition preferably contains at least one cationic surfactant, and may contain a co-surfactant. Suitable co-surfactants are selected from nonionic, anionic, amphoteric, zwitterionic, and semi-polar surfactants. A combination of cationic surfactants and co-surfactants may also be used. Preferably, the enhanced sanitizer release polymer composition are prepared with either cationic surfactants or a combination of cationic and nonionic surfactants. For nonwoven fabrics, the composition may include cationic binders or a combination of cationic and nonionic binders.
Suitable cationic surfactants include, for example:
dieicosyldimethyl ammonium chloride; didocosyldimethyl ammonium chloride; dioctadecyldimethyl ammonium chloride; dioctadecyldimethyl ammonium methosulphate; ditetradecyldimethyl ammonium chloride and naturally occurring mixtures of above fatty groups, e.g. di(hydrogenated tallow)dimethyl ammonium chloride; di(hydrogenated tallow)dimethyl ammonium metho-sulphate; ditallow dimethyl ammonium chloride; and dioleyldimethyl ammonium chloride.
Cationic surfactants also include imidazolinium compounds, for example, 1-methyl-1-(tallowylamido-) ethyl-2-tallowyl4,5-dihydroimidazolinium methosulphate and 1-methyl-1-(palmitoylamido)ethyl-2-octadecyl 4,5-dihydro-imidazolinium methosulphate. Other useful imidazolinium materials are 2-heptadecyl-1-methyl-1(2-stearoylamido)-ethyl-imidazolinium methosulphate and 2-lauryl-lhydroxyethyl-1-oleyl-imidazolinium chloride.
Further examples of the cationic surfactant include:
dialkyl (C 12 -C 22 )dimethylammonium chloride; alkyl(coconut)dimethylbenzylammonium chloride; octadecylamine acetate salt; tetradecylamine acetate salt; tallow alkylpropylenediamine acetate salt; octadecyltrimethylammonium chloride; alkyl(tallow)trimethylammonium chloride; dodecyltrimethylammonium chlorid; alkyl(coconut)trimethylammonium chloride; hexadecyltrimethylammonium chloride; biphenyltrimethylammonium chloride, alkyl(tallow)-imidazoline quaternary salt; tetradecylmethylbenzylammonium chloride; octadecyidimethylbenzylammonium chloride; dioleyidimethylammonium chloride; polyoxyethylene dodecylmonomethylammonium chloride; polyoxyethylene alkyl(C 12 -C 22 )benzylammonium chloride; polyoxyethylene laurylmonomethyl ammonium chloride; 1-hydroxyethyl-2-alkyl(tallow)-imidazoline quaternary salt; and a silicone cationic surfactant having a siloxane group as a hydrophobic group, a fluorine-containing cationic surfactant having a fluoroalkyl group as a hydrophobic group.
Anionic surfactants include, for example
from C 8 to C 20 alkylbenzenesulfonates; from C 8 to C 20 alkanesulfonates; from C 8 to C 20 alkylsulfates; from C 8 to C 20 alkylsulfosuccinates; and from C 8 to C 20 sulfated ethoxylated alkanols.
Nonionic surfactants include, for example, from C 6 to C 12 alkylphenol ethoxylates, from C 8 to C 20 alkanol alkoxylates, and block copolymers of ethylene oxide and propylene oxide. Optionally, the end groups of polyalkylene oxides can be blocked, whereby the free OH groups of the polyalkylene oxides can be etherified, esterified, acetalized and/or aminated. Another modification consists of reacting the free OH groups of the polyalkylene oxides with isocyanates. The nonionic surfactants also include C 4 to C 18 alkyl glucosides as well as the alkoxylated products obtainable therefrom by alkoxylation, particularly those obtainable by reaction of alkyl glucosides with ethylene oxide.
Amphoteric surfactants contain both acidic and basic hydrophilic groups. Amphoteric surfactants are preferably derivatives of secondary and tertiary amines, derivatives of quaternary ammonium, quaternary phosphonium or tertiary sulfonium compounds. The cationic atom in the quaternary compound can be part of a heterocyclic ring. The amphoteric surfactant preferably contains at least one aliphatic group, containing about 3 to about 18 carbon atoms.
At least one cationic surfactant is present in the enhanced sanitizer release polymer composition in an amount of from about 0.1 to about 99 weight percent, preferably from 0.5 to 50 weight percent, and more preferably from 1 to 10 weight percent, based on the total weight of the enhanced sanitizer release polymer composition. Preferable surfactants, such as the surfactants discussed above, can be obtained from Chicopee, Inc. of Dayton, New Jersey, a part of Polymer Group Inc. (PGI).
The composition of the additive agents, such as, for example, crosslinking or curing agents, that functionally and chemically improve the bonding of the cationic surfactant and optional co-surfactant to a particular substrate will depend on the composition and rheology of the substrate.
FIG. 1 is a flow chart outlining the steps of a process for manufacturing a treated substrate which may be utilized as, for example, a restaurant sanitizing towel. At step 10 , a suitable cationic (or alternatively, a nonionic) surfactant is selected for use in the sanitizer release polymer composition. At step 11 , it is determined whether or not a co-surfactant is also to be utilized in the composition. If not, the process moves to step 13 . However, if a co-surfactant is to be utilized, the process moves to step 12 where a suitable co-surfactant is selected from nonionic, anionic, amphoteric, zwitterionic, or semi-polar surfactants. At step 13 , it is then determined whether or not an additive agent is also to be utilized in the composition. If not, the process moves to step 15 . However, if an additive agent is to be utilized, the process moves to step 14 where an additive agent such as, for example, a cross-linking or curing agent is selected.
At step 15 , the concentration of the cationic surfactant is preferably adjusted in the composition to a range of 1 to 10 weight percent, based on the total weight of the enhanced sanitizer release polymer composition. The process then moves to step 16 where the enhanced sanitizer release polymer composition is applied to the surface of the substrate. It should be understood by one skilled in the art that the bonding of the enhanced sanitizer release polymer composition to a substrate will depend on the composition and rheology of the substrate. The enhanced sanitizer release polymer composition of the present invention may be applied to the surface of the substrate by any suitable method. For example, the enhanced sanitizer release polymer composition may be diluted with an organic solvent or water, and the resulting solution applied to the surface of the substrate by dip coating, spray coating or foam coating.
It should be understood by one skilled in the art that the bonding of the enhanced sanitizer release polymer composition to a substrate will depend on the composition and rheology of the substrate. The enhanced sanitizer release polymer of the present invention can be applied to the surface of the substrate by any suitable method. For example, the enhanced sanitizer release polymer composition may be diluted with an organic solvent or water, and the resulting solution may be applied to the surface of the substrate to be treated by dip coating, spray coating, or foam coating.
Table 1 below summarizes test results obtained with a substrate treated with the enhanced sanitizer release polymer composition in accordance with the teachings of the present invention. The test results show the QAT concentration (ppm) of a sanitizing solution that was utilized with different substrates over a four-hour period. The results for each substrate are compared with the QAT concentration of a control solution that was not used during the test period.
TABLE 1
Generic
Terry
Control
Invention
2 oz FST
Cloth
Linen
After
203
203
177
180
174
first Use
After 1
202
197
159
147
130
hour
After 2
202
203
133
119
88
hours
After 4
203
203
124
91
62
hours
It can be readily seen that the inventive substrate and composition maintained the QAT concentration at the original level throughout the four-hour test period, matching the control solution which was not used. Traditional substrates such as the generic 2-oz Food Service Towel (FST), the Terry cloth, and the linen all substantially reduced the QAT concentration of the sanitizing solution during the test period.
It is thus believed that the composition of the present invention will be apparent from the foregoing description. Although the invention has been described with reference to certain exemplary arrangements, it is to be understood that the forms of the invention shown and described are to be treated as preferred embodiments. Various changes, substitutions and modifications can be realized without departing from the scope of the invention as defined in the following claims. | An article for sanitizing a surface with a sanitizing solution while maintaining the concentration level of a sanitizer in the sanitizing solution at an effective concentration level. A substrate that absorbs and holds the sanitizing solution is treated with a sanitizer release polymer composition. The substrate may be a woven, nonwoven, or knit fabric, a foam or sponge, or the like. The sanitizer release polymer composition may include a cationic or nonionic surfactant or binder that is operable to maintain the concentration level of the sanitizer at the effective level during prolonged periods of use. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to lamps and more particularly to a modularized lamp mounted in a reflector device having advantages of being ease of mass production and being waterproof and airtight, and method of manufacturing same.
[0003] 2. Description of Related Art
[0004] A prior reflector belt (or reflector device) comprises a plurality of illuminators electrically coupled together by electric wires, a switch, a power supply (or batteries), a flash controller all coupled to the illuminators, and a reflective strip (or waterproof belt) for enclosing the above components. The reflector belt is typically stitched to a clothes or the like. Such design has been disclosed in Taiwanese Patent Published Nos. 355,642 and 383,121. However, it is impossible of manufacturing the prior art in a modularized, mass production since the coupling of illuminators, wires, and other electrical components and the stitching process are tedious and time consuming. Hence, the prior art finds it hard of putting into practice in industry. Moreover, in fact spacing between any two illuminators has to be adjusted in order to adapt to the article (e.g., shoulder belt or waist belt of a clothes) that the prior art is attached to. Thus, the manufacturer has to prepare many sets of illuminators having different spacings and belts of different lengths for fulfilling different needs of customers. This inevitably will increase the manufacturing cost and lower the production. Also, an additional waterproof treatment has to be done on the prior reflector belt. This further complicates the manufacturing process. To the worse one such reflector belt having a poor waterproof or airtight capability may cause danger (e.g., spark or explosion caused by exposing wires, flash controller, and illuminators to air having gas or other inflammable articles) when it is used in an environment requiring a highly safe operating standard. Hence, a need for improvement exists.
SUMMARY OF THE INVENTION
[0005] It is an object of the present invention to provide a lamp of reflector device and method of manufacturing same. By utilizing the present invention, advantages of being ease of mass production due to the provision of modular components, high quality, no additional equipment being required in the manufacturing process and thus saving cost, and being waterproof and airtight for enabling the reflector device to employ in an environment requiring a highly safe operating standard.
[0006] To achieve the above and other objects, the present invention provides a lamp of a reflector device, comprising a base including at least one aperture; a LED lamp mounted on the base; a support including side walls for forming a space and at least one aperture; a rivet assembly including at least one rivet inserted through the aperture of the base and the aperture of the support to fasten at the aperture of the base by soldering and electrically connect to the LED lamp; and bond filled in the space prior to solidification.
[0007] The present invention also provides a lamp of a reflector device, comprising a support including side walls for forming a space which is filled with bond; a base adhered on the space, the base including a plurality of apertures; a LED lamp mounted on an inner surface of the base facing the space; and a rivet assembly including a plurality of rivets inserted through the apertures of the base and fastened thereat by soldering, the rivets being projected from the support and being electrically connected to the LED lamp.
[0008] The present invention further provides a lamp of a reflector device, comprising a base including a plurality of apertures; a LED lamp mounted on the base; a support including a plurality of apertures; a rivet assembly including a plurality of rivets inserted through the apertures of the base and the apertures of the support to fasten at the apertures of the base by soldering and electrically connect to the LED lamp; and a cover plate secured onto the base, the cover plate including a plurality of upright pieces urged against a bottom of the support.
[0009] The present invention further provides a lamp of a reflector device, comprising a support including side walls for forming a space and a plurality of ribs in the space; a base in the space, the base including a plurality of apertures; a LED lamp secured to a bottom surface of the base facing the ribs; a rivet assembly including a plurality of rivets inserted through the apertures of the base and fastened thereat by soldering, the rivets being electrically connected to the LED lamp, and a cover plate secured onto a top surface of the base, the cover plate including a plurality of apertures for permitting the rivets to pass through.
[0010] The present invention further provides a lamp of a reflector device, comprising a support including side walls for forming a space and two upright, hollow cylinders; a LED lamp including two leads coupled to the cylinders, and a LED lamp element at a connecting point of the leads; a cover plate secured to a top surface of the support, the cover plate including a plurality of apertures; a rivet assembly including a plurality of rivets having a longitudinal channel, the rivets being inserted through the apertures of the cover plate to project from the support, and a plurality of conductive bars inserted in the channels of the rivets to electrically connect to the LED lamp.
[0011] The present invention further provides a lamp of a reflector device, comprising a base including a plurality of apertures; a LED lamp secured to the base; a rivet assembly including a plurality of rivets inserted through the apertures of the base to be electrically connected to the LED lamp, and an encapsulation formed of bond for enclosing the base, the LED lamp, and the rivet assembly wherein the rivet assembly is projected from the encapsulation.
[0012] The present invention further provides a method of manufacturing a lamp of a reflector device, comprising securing a LED lamp to a base; inserting a plurality of rivets through the base to electrically couple to the LED lamp; fastening the base together with the secured LED lamp and the rivets in a support by inserting the rivets through a plurality of apertures of the support; adhering a film on the support; filling bond in the support to enclose the base and the LED lamp for forming an encapsulation; baking the encapsulation; and removing the film.
[0013] The present invention further provides a method of manufacturing a lamp of a reflector device, comprising securing a LED lamp to a base; inserting a plurality of rivets through the base to electrically couple to the LED lamp; filling bond in a support; fastening the base together with the secured LED lamp and the rivets on the bond in the support for forming an encapsulation with the LED lamp facing the bond; and baking the encapsulation.
[0014] The present invention further provides a method of manufacturing a lamp of a reflector device, comprising securing a LED lamp to a base; inserting a plurality of rivets through the base to electrically couple to the LED lamp; fastening the base together with the secured LED lamp and the rivets in a support by inserting the rivets through a plurality of apertures of the support; filling bond in the support to enclose the base and the LED lamp; placing a cover plate on the support; and fastening the cover plate and the support together by means of a welder.
[0015] The present invention further provides a method of manufacturing a lamp of a reflector device, comprising securing a LED lamp to a base; inserting a plurality of rivets through the base to electrically couple to the LED lamp; fastening the base together with the secured LED lamp and the rivets in a support by inserting the rivets through a plurality of apertures of the support; placing a cover plate on the support; and fastening the cover plate and the support together by means of a welder.
[0016] The present invention further provides a method of manufacturing a lamp of a reflector device, comprising securing a LED lamp to a base; inserting a plurality of rivets through the base to electrically couple to the LED lamp; placing a cover plate on the support; and fastening the cover plate and the support together by means of a welder.
[0017] The present invention further provides a method of manufacturing a lamp of a reflector device, comprising securing a LED lamp to a base; inserting a plurality of rivets through the base to electrically couple to the LED lamp; placing the base together with the secured LED lamp and the rivets in a support; placing a cover plate on the support; inserting the rivets through a plurality of apertures of the cover plate; and fastening the cover plate and the support together by means of a welder.
[0018] The present invention further provides a method of manufacturing a lamp of a reflector device, comprising securing a LED lamp to a plurality of upright, hollow cylinders in a base; inserting a plurality of rivets through a cover plate to electrically couple to the LED lamp; placing a cover plate on the support; inserting the rivets through the support to project therefrom; and fastening the cover plate and the support together by means of a welder.
[0019] The present invention further provides a method of manufacturing a lamp of a reflector device, comprising securing a LED lamp to a base; inserting a plurality of rivets through the base to electrically couple to the LED lamp; placing the base together with the secured LED lamp and the rivets on a die of an injection molding machine; and activating a punch to press the base for forming a lamp unit.
[0020] The above and other objects, features and advantages of the present invention will become apparent from the following detailed description taken with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a perspective view of a portion of a reflector device according to the invention;
[0022] FIG. 2 is an exploded perspective view of a lamp unit of the reflector device;
[0023] FIG. 3 is a perspective view of FIG. 2 ;
[0024] FIG. 4 is a perspective view of a LED lamp of the lamp unit according to a first preferred embodiment of the invention;
[0025] FIG. 5 is an exploded perspective view of a LED lamp according to a second preferred embodiment of the invention;
[0026] FIG. 6 is a perspective view of the assembled LED lamp shown in FIG. 5 ;
[0027] FIG. 7 is an exploded perspective view of a LED lamp according to a third preferred embodiment of the invention;
[0028] FIG. 8 is a perspective view of the assembled LED lamp shown in FIG. 7 ;
[0029] FIG. 9 is a perspective view illustrating a process of injecting bond into the lamp unit;
[0030] FIG. 10 is a perspective view of the lamp unit after finishing the bond injection in FIG. 9 ;
[0031] FIG. 11 is an exploded perspective view illustrating a first step of injecting bond into the lamp unit according to the second preferred embodiment of the invention;
[0032] FIG. 12 is an exploded view illustrating a second step of flattening bond on the lamp unit shown in FIG. 11 ;
[0033] FIG. 13 is a perspective view illustrating a third step of adhering base onto the lamp unit shown in FIG. 12 ;
[0034] FIG. 14 is another perspective view of the lamp unit opposite to that shown in FIG. 13 ;
[0035] FIG. 15 is an exploded perspective view illustrating a first step of injecting bond into the lamp unit according to the third preferred embodiment of the invention;
[0036] FIG. 16 is an exploded perspective view illustrating a second step of flattening bond on the lamp unit shown in FIG. 15 ;
[0037] FIG. 17 is a perspective view illustrating a third step of adhering cover plate onto the lamp unit shown in FIG. 16 ;
[0038] FIG. 18 is an exploded view showing another cover plate to be mounted on the support assembly according to the third preferred embodiment of the invention;
[0039] FIG. 19 is a cross-sectional view of FIG. 18 ;
[0040] FIG. 20 is a perspective view of another cover plate mounted on the support assembly shown in FIG. 18 to form a lamp unit;
[0041] FIG. 21 is an exploded perspective view showing a lamp unit to be formed by welding according to a fourth preferred embodiment of the invention;
[0042] FIG. 22 is a perspective view of the formed lamp unit shown in FIG. 21 ;
[0043] FIG. 23 is an exploded perspective view showing a portion of lamp unit to be formed according to a fifth preferred embodiment of the invention;
[0044] FIG. 24 is a perspective view of the formed portion of lamp unit shown in FIG. 23 , where the portion of lamp unit is to be secured to still another cover plate by welding;
[0045] FIG. 25 is a perspective view of the formed lamp unit shown in FIG. 24 ;
[0046] FIG. 26 is an exploded perspective view showing a portion of lamp unit to be formed according to a sixth preferred embodiment of the invention;
[0047] FIG. 27 is a perspective view of the formed portion of lamp unit shown in FIG. 26 , where the portion of lamp unit is to be secured to yet another cover plate by welding;
[0048] FIG. 28 is a perspective view of the formed lamp unit shown in FIG. 27 ;
[0049] FIG. 29 is an exploded perspective view showing a lamp unit to be formed according to a seventh preferred embodiment of the invention;
[0050] FIG. 30 is an exploded perspective view of the partially formed lamp unit shown in FIG. 29 , where the support is to be secured to a further cover plate by welding;
[0051] FIG. 30A is a cross-sectional view of a portion of the formed lamp unit shown in FIG. 30 ;
[0052] FIG. 31 is a perspective view of the formed lamp unit shown in FIG. 30 ;
[0053] FIG. 32 is an exploded, perspective view showing portions of four lamp units placed on a die for forming four lamp units according to an eighth preferred embodiment of the invention;
[0054] FIG. 33 is an exploded view showing a punch to be pressed on the die shown in FIG. 32 ;
[0055] FIG. 34 is a view similar to FIG. 33 , where four lamp units are formed on the die after lifting the punch;
[0056] FIGS. 35 to 37 are perspective views showing three different shapes of lamp units formed in a manufacturing process the same as that shown in FIGS. 32 to 34 ;
[0057] FIG. 38 is an exploded perspective view showing a waterproof treatment being performed on a lamp unit to be formed;
[0058] FIG. 39 is a side view in part section of the formed lamp unit shown in FIG. 38 ;
[0059] FIG. 40 is an exploded perspective view showing another waterproof treatment being performed on a lamp unit to be formed;
[0060] FIG. 41 is a side view in part section of the formed lamp unit shown in FIG. 40 ;
[0061] FIG. 42 is an exploded perspective view showing a further waterproof treatment being performed on a lamp unit to be formed; and
[0062] FIG. 43 is a side view in part section of the formed lamp unit shown in FIG. 42 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0063] Referring to FIG. 1 , there is shown two lamp units 1 mounted on a reflective belt unit 2 to form a reflector device 100 in accordance with the invention. The reflector device 100 is used as warning means due to the flashing feature of the lamp units 1 . Also, the reflector device 100 finds an application of warning by stitching to clothes or the like. The components of the lamp unit 1 will be described in detail below.
[0064] Referring to FIGS. 2 to 4 , the lamp unit 1 comprises a base 11 , a LED (light-emitting diode) lamp 12 , a seat assembly 13 , and a rivet assembly 14 including a plurality of rivets 141 and 142 . The base 11 comprises two electric wires 111 , 112 and two apertures 113 , 114 . A contact 115 is provided at the aperture 113 and another contact 116 is provided at the aperture 114 so as to electrically couple to the wires 111 and 112 respectively as a portion of the electrical connection of the lamp unit 1 . A plurality of holes 117 are provided at corners of the base 11 as means of bond injection or ventilation. The LED lamp 12 is provided at a connecting point of the wires 111 and 112 and comprises a LED die 121 on the wire 111 and a lead 122 coupled between the LED die 121 and the wire 112 . The LED lamp 12 is enclosed by an encapsulation 123 (e.g., epoxy) to form a COB (chip on board) based LED.
[0065] The seat assembly 13 is adapted to receive the LED lamp 12 and the rivet assembly 14 and comprises a rectangular support 13 A having four side walls for forming a space 130 to receive the base 11 . The seat assembly 13 further comprises two spaced apertures 131 and 132 and a plurality of holes 133 adjacent the corners. The holes 133 are aligned with the holes 117 as means of bond injection or ventilation. The rivets 141 and 142 are inserted through the apertures 113 , 114 of the base 11 and the apertures 131 and 132 of the support 13 A to fasten on the contacts 115 and 116 by soldering. As such, the base 11 is fastened within the support 13 A to form a support assembly 15 for the facilitation of a subsequent encapsulation (as detailed later). In addition, a plurality of waterproof rings 134 are provided at the underside of the support 13 A and each waterproof ring 134 is tightly put on the passed shank of either rivet 141 or 142 . As such, waterproof capability of the reflector device can be obtained by mounting the lamp unit 1 on the belt unit 2 and then flattening the shanks of the rivets 141 and 142 to compress the waterproof rings 134 (see FIG. 9 ).
[0066] A number of other preferred embodiments of the support assembly 15 will be described in detailed below.
[0067] Referring to FIGS. 5 and 6 , in the preferred embodiment of support assembly 15 the LED lamp 12 comprises a LED die 121 A which is formed at a connecting point of the wires 111 and 112 by SMD (surface mounting) (i.e., SMD based LED). Next, insert the rivets 141 and 142 through the apertures 113 , 114 on the base 11 and the apertures 131 and 132 on the support 13 A to fasten on the contacts 115 and 116 by soldering. As an end, a support assembly 15 A is formed.
[0068] Referring to FIGS. 7 and 8 , in the preferred embodiment of support assembly 15 B different from above the support assembly 15 B comprises a support 13 A, a rivet assembly 14 , and a LED lamp 12 B in which the LED lamp 12 B comprises two leads 124 and 125 and a LED lamp element 121 B at a connecting point of the leads 124 and 125 (i.e., lead frame based LED is formed). In assembly, first insert the rivets 141 and 142 through the apertures 131 and 132 of the support 13 A. Next, insert bent portions of the leads 124 and 125 into apertures 143 and 144 of the rivets 141 and 142 respectively. Finally, the LED lamp 12 B is secured to the rivets 141 and 142 by soldering. As an end, a support assembly 15 B is formed.
[0069] Referring to FIGS. 9 and 10 , a process of injecting bond into the lamp unit 1 according to a first preferred embodiment of the invention is shown. As shown in FIG. 9 , a film 16 is adhered on the surface of the space 130 in the support assembly 15 (or support assembly 15 A or 15 B). Next, a process of bond (e.g., epoxy) injection is performed at the holes 133 to fill bond in the space 130 to enclose the base 11 and the LED lamp 12 in the support 13 A and form an encapsulation 13 B of the seat assembly 13 . The support assembly 15 is then sent to an oven to bake. After baking, the film 16 can be removed to form a lamp unit 1 having exposed rivets 141 and 142 ( FIG. 10 ).
[0070] Referring to FIGS. 11 and 12 , a process of injecting bond into the lamp unit 1 according to a second preferred embodiment of the invention is shown. The LED lamp 12 is a COB based LED (as shown), SMD based LED, or lead frame based LED. The LED lamp 12 and the rivet assembly 14 are mounted in the base 11 . Next, a process of bond (e.g., epoxy) injection is performed to fill bond in the space 130 to form an encapsulation 13 B. The base 11 is then placed on the support 13 A for covering prior to sending to an oven to bake. After baking, a lamp unit 1 having exposed rivets 141 and 142 is formed. Referring to FIGS. 13 and 14 , a peripheral groove 135 (see FIG. 11 ) is formed around inner surfaces of the walls of the support 13 A for facilitating a fitting of the base 11 onto the support 13 A (i.e., onto the groove 135 ) and adhesion thereafter.
[0071] Referring to FIGS. 15 and 16 , a process of injecting bond into the lamp unit 1 according to a third preferred embodiment of the invention is shown. The base 11 , the LED lamp 12 , and the rivet assembly 14 are mounted in the support 13 A to form a support assembly 15 (or support assembly 15 A or 15 B). Next, fill bond in the space 130 to form an encapsulation 13 B. A cover plate 17 is then placed on the support 13 A for covering prior to being fastened together by means of an ultrasonic welder. As an end, a lamp unit 1 having exposed rivets 141 and 142 is formed (see FIG. 17 ). Also, a peripheral groove 136 is formed around inner surfaces of the walls of the support 13 A for facilitating a fitting of the cover plate 17 onto the support 13 A (i.e., onto the groove 136 ) and adhesion thereafter.
[0072] Referring to FIGS. 18 and 19 , a peripheral ridge 137 is formed around projecting edges of the support 13 A for facilitating a fitting of a peripheral trough 181 of a cap-like cover plate 18 onto the support 13 A (i.e., fastened at the ridge 137 ) to form a lamp unit 1 (see FIG. 20 ).
[0073] Referring to FIG. 21 , a lamp unit to be formed by welding according to a preferred embodiment of the invention is shown. The base 11 , the LED lamp 12 , and the rivet assembly 14 are mounted in the support 13 A to form a support assembly 15 (or support assembly 15 A or 15 B). Next, a cover plate 19 is placed on the support 13 A for covering. The cover plate 19 comprises a plurality of equally spaced apart upright pieces 191 urged against the inner surfaces of the walls of the support 13 A as support. Next, the cover plate 19 and the support 13 A are fastened together by means of a high-frequency or ultrasonic welder. As an end, a lamp unit 1 having exposed rivets 141 and 142 is formed (see FIG. 22 ).
[0074] Referring to FIGS. 23 and 24 , two opposite posts 138 having a top cavity are formed in the space 130 for fastening the leads 124 and 125 of the LED lamp 12 B (i.e., lead frame based LED). Next, insert the rivets 141 and 142 through the apertures 131 and 132 on the support 13 A. Next, fasten the leads 124 and 125 of the LED lamp 12 B on the rivets 141 and 142 by soldering. As an end, a support assembly 15 B′ is formed. A cover plate 21 is then placed on the support 13 A for covering. The cover plate 21 comprises two spaced upright cylinders 212 urged against the rivets 141 and 142 . Next, the cover plate 21 and the support 13 A are fastened together by means of a high-frequency or ultrasonic welder. As an end, a lamp unit 1 having exposed rivets 141 and 142 is formed (see FIG. 25 ).
[0075] Referring to FIGS. 26 and 27 , a rib 139 is provided at an inner surface of each wall of the support 13 A (i.e., in the space 130 ). The LED lamp 12 B is a COB based LED (as shown), SMD based LED, or lead frame based LED. The LED lamp 12 B and the rivet assembly 14 are mounted in the base 11 . Next, turn the base 11 upside down prior to placing the base 11 on the support 13 A to urge against the ribs 139 . Next, a cover plate 21 is placed on the support 13 A for covering with the shanks of the rivets 141 and 142 being projected from apertures 211 , 212 of the cover plate 21 . Next, the cover plate 21 and the support 13 A are fastened together by means of a high-frequency or ultrasonic welder. As an end, a lamp unit 1 having exposed rivets 141 and 142 is formed (see FIG. 28 ).
[0076] Referring to FIGS. 29, 30 , and 30 A, a lamp unit 1 to be formed by welding according to a preferred embodiment of the invention is shown. On the space 130 there are provided two spaced, upright, hollow cylinders 161 and 162 each having a longitudinal slit 163 or 164 . The leads 124 and 125 of the LED lamp 12 B (i.e., lead frame based LED) are inserted in the slits 163 and 164 for fastening. Next, insert the rivets 141 and 142 through the apertures 221 and 222 of a cover plate 22 to project from the cover plate 22 which is in turn placed on the support 13 A for covering. Next, conductive bars 165 and 166 are inserted in the slits 163 and 164 and the hollow shanks of the rivets 141 and 142 respectively. Next, fasten the cover plate 22 and the support 13 A together by means of a high-frequency or ultrasonic welder. As an end, a lamp unit 1 having exposed rivets 141 and 142 is formed (see FIG. 31 ).
[0077] Referring to FIGS. 32 to 34 , forming process of the lamp unit is illustrated. The LED lamp 12 is a COB based LED (as shown), SMD based LED, or lead frame based LED. The LED lamp 12 and the rivets 141 and 142 are mounted in the base 11 . Next, the base 11 is placed on a die A of an injection molding machine. An encapsulation 13 B is then formed after performing the manufacturing steps shown in FIGS. 33 and 34 . FIGS. 35 to 37 show three different shapes of lamp units 1 A formed in a manufacturing process the same as that shown in FIGS. 32 to 34 in which each lamp unit 1 A has exposed rivets 141 and 142 .
[0078] Referring to FIGS. 38 and 39 , two waterproof rings 134 are integrally formed with a seat assembly 13 . The rivets 141 and 142 are then inserted through the lamp unit 1 , the waterproof rings 134 , and the belt unit 2 prior to being flattened to compress the waterproof rings 134 . As such, a portion of waterproof treatment is achieved in the joining portion of the rivets 141 and 142 , the belt unit 2 , and the lamp unit 1 . Finally, a waterproof pad 31 is adhered on the belt unit 2 to cover the flattened portions of the rivets 141 and 142 thereon. As an end, a complete waterproof treatment is achieved.
[0079] Referring to FIGS. 40 and 41 , two waterproof rings 134 A are placed on apertures of the seat assembly 13 . The rivets 141 and 142 are then inserted through the lamp unit 1 (i.e., the apertures of the seat assembly 13 ), the waterproof rings 134 A, and the belt unit 2 prior to being flattened to compress the waterproof rings 134 A. As such, a portion of waterproof treatment is achieved in the joining portion of the rivets 141 and 142 , the belt unit 2 , and the lamp unit 1 together. Finally, a waterproof pad 31 is adhered on the belt unit 2 to cover the flattened portions of the rivets 141 and 142 thereon. As an end, a complete waterproof treatment is achieved.
[0080] Referring to FIGS. 42 and 43 , two waterproof rings 134 are integrally formed with a seat assembly 13 . Also, two second waterproof rings 134 B are in the waterproof rings 134 . The rivets 141 and 142 are then inserted through the lamp unit 1 , the waterproof rings 134 , the second waterproof rings 134 B, and the belt unit 2 prior to being flattened to compress the waterproof rings 134 and second waterproof rings 134 B. As such, a portion of waterproof treatment is achieved in the joining portion of the rivets 141 and 142 , the belt unit 2 , and the lamp unit 1 . Finally, a waterproof pad 31 is adhered on the belt unit 2 to cover the flattened portions of the rivets 141 and 142 thereon. As an end, a complete waterproof treatment is achieved.
[0081] In brief, a number of configurations of the invention are made possible. For example, after mounting the LED lamp 12 and the rivets 141 and 142 in the base 11 , place one or more bases 11 on a die of injection molding machine. Finally, one or more encapsulations 13 B (i.e., lamp units 1 ) are formed by punching. Alternatively, after mounting the LED lamp 12 and the rivets 141 and 142 in the support 13 A, form an encapsulation 13 B on the support 13 A or place a cover plate 17 , 18 , or 19 on the support 13 A prior to encapsulation. As to the rivets 141 and 142 , they can be projected from the support 13 A, the base 11 , the encapsulation 13 B, or the cover plate 17 , 18 , or 19 . As to the encapsulation, it can be one of bond injection, bond injection to adhere to the cover plate 17 , 18 , or 19 , plate based heating for encapsulation by means of a high-frequency or ultrasonic welder, and injection molding.
[0082] While the invention herein disclosed has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims. | Provided is a lamp of reflector device and method of manufacturing same. The lamp comprises a base including a plurality of apertures, a LED lamp mounted on the base, a support including side walls for forming a space and a plurality of apertures, a rivet assembly including a plurality of rivets inserted through the apertures of the base and the apertures of the support to fasten at the apertures of the base by soldering and electrically connect to the LED lamp, and bond filled in the space prior to solidification. The invention has advantages of being ease of mass production due to modularized design. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is the National Stage of International Application No. PCT/NL2015/050882 filed Dec. 18, 2015, which claims the benefit of Netherlands Application No. NL 2014023, filed Dec. 19, 2014, the contents of which is incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The present invention relates to an improved process for the preparation of a benzene compound, more in particular to a process for the preparation of a benzene compound which comprises a process step wherein a furan compound is reacted with an olefin. The reaction of the furan compound with the olefin may be a Diels-Alder reaction.
BACKGROUND OF THE INVENTION
[0003] Such a process is known from e.g. WO 2013/048248. In this application it is described that there is an increasing tendency to create chemicals from renewable sources. Research has been undertaken to prepare chemicals from biomass materials, such as carbohydrates, e.g. cellulose, starch, hemicelluloses, sugars, glucose and fructose. Dehydration of such carbohydrates may yield valuable chemicals, including levulinic acid, furfural, hydroxymethyl furfural and derivatives thereof. In WO 2013/048248 the reaction is disclosed wherein a 2-alkoxymethyl furan is reacted with a substituted olefin to yield an unsaturated bicyclic ether. The bicyclic ether is subsequently dehydrated and aromatized to yield a substituted benzene compound. Via this process substituents on the 1,2-, 1,3- or 1,2,3-positions of the benzene ring are obtained. The thus obtained products may elegantly be converted by oxidation into phthalic acid, isophthalic acid and hemimellitic acid.
[0004] In US 2010/0127220 a process for the manufacture of substituted pentacenes is described. The process includes a step wherein dimethylfuran is reacted with maleic anhydride via a Diels Alder reaction to yield a bicyclic unsaturated ether. The bicyclic unsaturated ether is then dehydrated and aromatized under aromatization conditions to yield 4,7-dimethyl-isobenzofuran-1,3-dione (see reaction scheme A, wherein step (i) is a Diels-Alder reaction and step (ii) is the aromatization).
[0000]
[0005] It appears that the yield of the bicyclic unsaturated ether can be relatively high. An example in WO 2013/048248 shows that the yield of the bicyclic unsaturated ether can be about 96%. According to an example in US 2010/0127220 a yield of about 72% could be obtained in the preparation of the bicyclic unsaturated ether (cf. US 2010/0127220, Example 1). However, both documents also show that the yield of the subsequent dehydration is significantly lower. According to Example 2 in WO 2013/048248 the desired benzene compound could be obtained in a yield of 37%, whereas the yield on the desired benzene compound in US 2010/0127220 amounted to about 41%. When the yields are calculated on the basis of the starting furan compound the overall yield is about 30 to 35% according to the examples in these documents.
[0006] It has now been found that the overall yield of the preparation process can be increased when the dehydration step of the bicyclic unsaturated ether is preceded by a hydrogenation step, wherein the unsaturated bond of the bicyclic unsaturated ether that is obtained in the reaction of the furan compound with the olefin is hydrogenated. Surprisingly, the saturated bicyclic ether thus obtained can still be dehydrated and aromatized, yielding the desired benzene compound.
SUMMARY OF THE INVENTION
[0007] Accordingly, the present invention provides a process for the preparation of a benzene compound which comprises
[0000] (i) reacting a furan compound of formula (I):
[0000]
[0000] wherein R 1 and R 2 are the same or different and independently selected from the group consisting of hydrogen, alkyl, aralkyl, —CHO, —CH 2 OR 3 , —CH(OR 4 )(OR 5 ), —COOR 6 , wherein R 3 , R 4 and R 5 are the same or different and are independently selected from the group consisting of hydrogen, alkyl, aryl, alkaryl, aralkyl, alkylcarbonyl and arylcarbonyl, or wherein R 4 and R 5 together form an alkylene group, and wherein R 6 is selected from the group consisting of hydrogen, alkyl and aryl,
with an olefin of the formula (II)
[0000] R 7 —CH═CH—R 8 (II),
[0000] wherein R 7 and R 8 are the same or different and are independently selected from the group consisting of hydrogen, sulfonate, —CN, —CHO, and —COOR 9 , wherein R 9 is selected from the group consisting of hydrogen, and an alkyl group, or R 7 and R 8 together form a —C(O)—O—(O)C— group or a —C(O)—NR 10 —C(O)— group, wherein R 10 represents hydrogen, an aliphatic or an aromatic group,
to produce an unsaturated bicyclic ether having an unsaturated carbon-carbon bond;
(ii) hydrogenating the unsaturated carbon-carbon bond in the unsaturated bicyclic ether to produce a saturated bicyclic ether; and
(iii) dehydrating and aromatizing the saturated bicyclic ether to produce the benzene compound.
DETAILED DESCRIPTION OF THE INVENTION
[0008] The first step of forming the unsaturated bicyclic ether from the furan compound of formula (I) and the olefin of formula (II) seems to occur via a Diels-Alder-type reaction. It is known that Diels-Alder reactions may be reversible. Then the so-called retro-Diels-Alder reaction takes place. Without wishing to be bound by any theory, it is believed that by the hydrogenation of the double bond in the Diels-Alder adduct, i.e. the unsaturated bicyclic ether, the occurrence of the retro-Diels-Alder reaction is prevented. It is further surprising that in spite of the saturation that is introduced into the bicyclic ether, the dehydration and aromatization of the saturated ether does occur in satisfactory yields.
[0009] It is known that in Diels-Alder reactions the reaction rate is expedited by providing electron withdrawing groups on the olefin, i.e. the dienophile, and electron donating groups on the furan compound, i.e. the diene. Electron withdrawing groups include cyano, sulfonate, carboxylic acid, carboxylic anhydride, carboxylic ester, ketone and aldehyde groups. Electron donating groups include hydroxy, ether, aliphatic and aromatic hydrocarbon groups. Accordingly, the present invention preferably employs a furan compound of formula (I), wherein R 1 and R 2 are the same or different and independently selected from the group consisting of hydrogen, alkyl, aralkyl, —CHO, —CH 2 OR 3 , wherein R 3 is selected from the group consisting of hydrogen and alkyl. More preferably, R 1 , R 2 and R 3 are independently selected from the group consisting of hydrogen and an alkyl group having 1 to 4 carbon atoms.
[0010] The olefin of formula (II) suitably comprises compounds, wherein R 7 and R 8 are the same or different and are independently selected from the group consisting of hydrogen, —CHO and —COOR 9 , wherein R 9 is selected from the group consisting of hydrogen, and an alkyl group having 1 to 4 carbon atoms, or R 7 and R 8 together form a —C(O)—O—(O)C— group. More preferably, R 7 and R 8 together form a —C(O)—O—(O)C— group. R 7 and R 8 together may also form a —C(O)—NR 10 —C(O)— group, wherein R 10 represents hydrogen, an aliphatic or an aromatic group. When R 10 is an aromatic or aliphatic group it may be optionally substituted. Suitable substituents include hydroxyl, alkoxy, carbonyl, amino and hydrocarbonaceous groups. R 10 may suitably be selected from alkyl and aromatic groups. The alkyl group has typically from 1 to 15 carbon atoms, preferably from 1 to 6 carbon atoms. R 10 is suitably an aromatic group, which may be a heterocyclic aromatic moiety or a hydrocarbonaceous aromatic moiety. R 10 is preferably a hydrocarbonaceous aromatic moiety with 6 to 10 carbon atoms, more preferably a phenyl group.
[0011] The Diels-Alder reaction of the furan derivative of formula (I) with the olefin of formula (II) can be carried out at a broad variety of reaction conditions. Although elevated pressures may be applied, e.g., from 1 to 100 bar, more preferably, from 1 to 10 bar, it is most feasible to conduct the reaction at autogenous pressure. The reaction temperature may also vary from far below 0° C. to elevated temperatures. Suitably, the reaction temperature varies from 0° C. to 150° C., preferably from 20° C. to 100° C.
[0012] Known Diels-Alder catalysts may be used in the reaction. Suitable catalysts include Lewis acids, e.g., aluminium, boron, zinc, hafnium, lithium or iron compounds, such as AlCl 3 , Al(Et)Cl 2 , Al(Et) 2 Cl, BF 3 , B(Ac) 3 , ZnCl 2 , ZnBr 2 , Zn(Ac) 2 , HfCl 4 , FeCl 3 , Fe(Ac) 3 , FeCl 2 and Fe(Ac) 2 , Zn(OTf) 2 (zinc triflate), LiOTf, Li (bisoxalato)borate, but also halides of tin or titanium, such as SnCl 4 and TiCl 4 . When a catalyst is used, the amount thereof may vary within wide ranges, such as from 0.01 to 50% mol, based on the furan compound of formula (I) or the olefin of formula (II), whichever is present in the lowest molar amount. Preferably, the amount of Diels-Alder catalyst is in the range of 0.1 to 20% mol, more preferably from 0.2 to 15% mol, based on the amount of the furan compound of formula (I) or the olefin of formula (II), whichever is present in the lowest molar amount. However, dependent on the electron donating behavior of the substituents on the furan compound and the electron withdrawing nature of the substituents on the olefin, the reactants may be so reactive that a catalyst is not needed to make the reaction occur. Evidently, in such a case the skilled person may decide not to use a catalyst in view of economic considerations.
[0013] Although it is possible to conduct the present reaction between the furan derivative and the olefin in the presence of a solvent, it is preferred to refrain from employing a solvent. Nevertheless, in certain cases the use thereof may be convenient. The use of a solvent is convenient if the furan derivative and/or the unsaturated bicylic ether that is being produced is solid under the reaction conditions. The liquid phase thus obtained makes it easier to handle the reactant and/or the reaction products. Thereto, the solvent may be selected from a wide range of potential liquids. Suitably, the solvent is selected from the group consisting of water, alcohols, esters, ketones, amides, aldehydes, ethers, ionic liquids and sulphoxides.
[0014] Advantageously, the solvents contain from 1 to 20 carbon atoms. Examples of suitable alcohols include C 1 -C 4 alcohols, in particular methanol, ethanol, n-propanol, isopropanol, butanol-1, butanol-2, 2-methylpropanol and tert-butanol. Suitable esters include the C 1 -C 10 alkyl esters of C 1 -C 8 carboxylic acids, such as methyl formate, methyl acetate, ethyl formate, ethyl acetate, methyl propionate, ethyl propionate, methyl butyrate, ethyl butyrate and ethylhexyl acetate. Suitable ketones contain 2 to 8 carbon atoms, such as acetone, butanone and methyl iso-butyl ketone. Suitable amides include acetamide and formamide, optionally substituted by one or two alkyl groups with 1 to 6 carbon atoms, such as N,N-dimethyl acetamide. Examples of suitable ethers include dialkyl ethers wherein each alkyl moiety is selected from a C 1 -C 6 alkyl group, such as dimethyl ether, diethyl ether and methyl tert-butyl ether, and also cyclic ethers such as tetrahydrofuran or dioxane. Suitable aldehydes include C 1 -C 6 aldehydes, such as formaldehyde, acetaldehyde, propanal and hexanal. Suitable ionic liquids comprise a pyridinium or imidazolinium moiety. Examples include pyridinium chloride, 1-ethyl-3-methylimidazolium dicyanamide and 1-butyl-3,5-dimethylpyridinium bromide. A suitable sulphoxide is dimethylsulphoxide.
[0015] The relative amounts of the furan derivative of formula (I) and the olefin of formula (II) may vary. Since stoichiometry shows that one mole of furan may react with one mole of olefin, the molar ratio of the amount furan derivative to the amount of olefin generally will be about 1:1, although the person skilled in the art may decide to provide one of the reactants in excess to promote the reaction and/or to facilitate the complete conversion of the other reactant. Therefore, the molar ratio between the amount of furan derivative to the amount of olefin suitably ranges from 0.1:1 to 10:1, preferably from 0.5:1 to 2:1, most preferably about 1:1.
[0016] For the Diels-Alder reaction, the reactants may be added in a batch-wise or a continuous fashion. In a batch-wise fashion both the furan derivative and olefin are charged to a vessel, e.g. an autoclave, and made to react with each other. Typically one of the reactants may be added in portions, over a period of time, to the other reactant, e.g. by using a syringe as described in US 2010/0127220. If desired, the reaction mixture is maintained at a desired temperature for a period of time, e.g. whilst stirring to increase the yield of product. In a continuous fashion both a stream of furan derivative and a stream of olefin are fed to a reactor where they are contacted and from which reactor continuously a stream of product is withdrawn. The flow rate in a continuous reactor should be adapted such that the residence time is sufficient to allow a satisfactory conversion of the furan derivative and olefin. The Diels-Alder reaction is suitably carried out in a batch or continuous reactor wherein the residence time is from 0.1 to 72 hours, preferably from 0.5 to 48 hours.
[0017] When the process is conducted in a continuous mode, the reactor may be selected from various types of reactors, e.g. a continuous stirred tank reactor, a plug flow reactor or a trickle bed reactor when a solid catalyst is used.
[0018] The unsaturated bicyclic ether thus obtained is subsequently hydrogenated. Thereto the unsaturated bicyclic ether is suitably contacted with a reducing agent. Possible reducing agents include hydrides, such as LiH, NaH, NaAlH 4 , LiAlH 4 , NaBH 4 and CaH 2 . However, the use of gaseous hydrogen is preferred. When hydrogen gas is used as hydrogenation agent the use of a hydrogenation catalyst is desired. Accordingly, the present invention preferably is conducted in a process wherein the unsaturated carbon-carbon bond in the unsaturated bicyclic ether is hydrogenated using gaseous hydrogen in the presence of a hydrogenation catalyst. Suitable hydrogenation catalysts comprise one or more metals or metal compounds selected from the metals in the Groups 8 to 10 of the Periodic Table of Elements, preferably on a carrier. Such suitable metals include Pt, Pd, Ru, Rh, Ir, Os, Ni, Co and mixtures thereof.
[0019] The carriers for these metals may be selected from a variety of conventional carriers. Preferably, the carrier has been selected from alumina, silica, titania, zirconia, silica-alumina, carbon, more preferably activated carbon, and mixtures thereof. The loading of the metal or metals on the carrier may also be varied within wide ranges. The content of metal on the hydrogenation catalyst may be in the range of 0.5 to 25% wt, more suitably from 1 to 10% wt, based on the weight of the hydrogenation catalyst.
[0020] Although the hydrogenation catalyst may be selected from any combination of the metals and carriers that are described herein, the most preferred hydrogenation catalyst is selected from palladium, platinum or ruthenium on activated carbon, in particular palladium on activated carbon.
[0021] It may be convenient to hydrogenate the unsaturated carbon-carbon bond in the unsaturated bicyclic ether in the presence of a solvent. The use of a solvent may render it easier to handle and to disperse the hydrogenation catalyst uniformly in the mixture of unsaturated bicyclic ether, gaseous hydrogen and solvent. The solvent may also facilitate the uptake of hydrogen, which promotes the hydrogenation reaction. When a solvent is used the solvent can suitably be selected from the group consisting of hydrocarbons, alcohols, esters, ketones, amides, aldehydes, ethers, ionic liquids and sulphoxides. It is advantageous to use a solvent that is not subjected to possible hydrogenation itself. Therefore, the use of saturated hydrocarbons or ethers is more suitable. Such suitable solvents, therefore, include C 4 -C 10 aliphatic hydrocarbons or mixtures thereof and saturated ethers such as dialkyl ethers, wherein each alkyl moiety is selected from a C 1 -C 6 alkyl group, or mixtures thereof, or cyclic ethers such as dioxane and tetrahydrofuran. Good results have been obtained by using a solvent that has been selected from the group consisting of saturated hydrocarbons and ethers, in particular cyclic ethers.
[0022] The hydrogenation conditions may vary within wide ranges. The skilled person will realize that the conditions may also be varied in accordance with the nature of the substituents. In order to selectively hydrogenate the unsaturated carbon-carbon bond in the unsaturated bicyclic ether, the hydrogenation temperature is kept at a moderate level. Low temperatures were found to reduce the retro Diels-Alder reactions. Suitably, the unsaturated bicyclic ether is hydrogenated at a temperature of 0 to 150° C., preferably from 10 to 100° C., more preferably from 20 to 80° C.
[0023] The hydrogen pressure may also be selected within a broad range. The unsaturated bicyclic ether is suitably hydrogenated at a hydrogen pressure of 1 to 125 bar, preferably at a hydrogen pressure of 10 to 100 bar. The reaction is completed when no hydrogen is taken up anymore. The duration of the hydrogenation reaction may typically be in the range of 0.5 to 24 hrs, suitably from 2 to 16 hrs.
[0024] Surprisingly the hydrogenation reaction can be substantially quantitative. Thus the saturated bicyclic ether is obtained in excellent yield and purity. If desired, the hydrogenated saturated bicyclic ether may be purified. This may be accomplished by washing the saturated bicyclic ether and/or by recrystallization from a suitable solvent. Such solvents can be selected from alcohols, hydrocarbons, esters, ethers and mixtures thereof.
[0025] The saturated bicyclic ether is then subjected to dehydration and aromatization. Since in the dehydration also hydrogen is liberated, the process according to the present invention does not require net hydrogen addition.
[0026] According to WO 2013/048248 the dehydration of the unsaturated bicyclic ether can be accomplished in the presence of a catalyst. The catalyst may be acidic or alkaline. A preference is expressed for an alkaline catalyst, such as an alcoholate, hydroxide, carboxylate or carbonate. Also in the process according to the present invention the saturated bicyclic ether is suitably dehydrated and aromatized in the presence of a catalyst. Different from the preference in WO 2013/048248, it has now surprisingly been found that the dehydration and aromatization of the saturated bicyclic ether is suitably performed in the presence of an acid catalyst. The acid catalyst can be a homogeneous or a heterogeneous catalyst. The use of a homogeneous catalyst boils down to a process wherein the reaction is carried out in a homogeneous liquid phase and the catalyst is comprised in that liquid phase. Suitable homogeneous catalysts that may be dissolved in the appropriate solvent to yield a homogeneous catalytic environment include organic and inorganic acids, such as alkane carboxylic acid, arene carboxylic acid, alkane sulphonic acid, such as methane sulphonic acid, arene sulphonic acid, such as p-toluene sulphonic acid, sulphuric acid, phosphoric acid, hydrochloric acid, hydrobromic acid and nitric acid. When an arene carboxylic acid is the eventually desired product, such as phthalic acid, methylphthalic acid, isophthalic acid or hemimellitic acid, a preferred arene carboxylic acid is selected from phthalic acid, methylphthalic acid, isophthalic acid and hemimellitic acid, since these acids provides catalytic activity and do not add an extraneous chemical to the reaction mixture.
[0027] Preferably, the dehydration and aromatization is carried out in the presence of a heterogeneous catalyst. When a heterogeneous catalyst is used, the reaction is conducted in a liquid reactant phase and a solid catalyst phase. Hence, the catalyst is preferably a solid catalyst. Examples of solid acidic catalysts include amorphous silica-alumina, zeolites, preferably zeolites in their H-form, phosphoric acid on a carrier, sulfonated activated carbon and acidic ion exchange resins, wherein zeolites, ion exchangers, sulfonated activated carbon and combinations thereof are preferred. Zeolites are particularly preferred. Zeolites are the preferred catalysts since they can withstand relatively high reaction temperatures and their acidity can be adjusted by selecting the desired level of ion exchange of metal ions by protons and/or by varying the silica-alumina ratio in the zeolite. The zeolite can be selected from a variety of zeolitic structures. In principle all zeolitic structures as defined in the Database of Zeolite Structures and approved by the Structure Committee of the International Zeolite Association can be used. Good results have been obtained with the zeolites selected from the group consisting of zeolite Y, zeolite X, zeolite beta, mordenite and mixtures thereof. Zeolites are crystalline aluminosilicates that contain certain alkali and alkaline earth cations, such as sodium or magnesium ions. By varying the silica/alumina ratio and by varying the removal of the alkali and alkaline earth metal cations and replacing them by protons, the acidity of the zeolite can be adjusted. Typically, the zeolite has a silica/alumina molar ratio in the range of 1 to 200. Suitably the zeolite has been subjected to ion exchange to remove alkaline and alkaline earth cations and have these cations replaced by protons. An alternative preferred solid acidic catalyst is sulfonated activated carbon. This catalyst comprises sulfonic acid groups attached to activated carbon. The preparation thereof has e.g. been described in Liu et al, Molecules, 2010, 15, 7188-7196.
[0028] The skilled person will realize that the amount of acidic catalyst can be varied within broad ranges. It has been found that it is advantageous to use the acidic catalyst in an amount in the range of 10% wt to 50% wt, based on the amount of substrate, i.e. the saturated bicyclic ether. When smaller amounts of catalyst are used the reaction may take longer.
[0029] It is advantageous to dehydrate and aromatize the saturated bicyclic ether neat. This promotes the contact of the saturated bicyclic ether with the catalyst. In other embodiments it is desirable to conduct the dehydration and aromatization in the presence of a solvent. The dispersion of the solid catalyst is then facilitated. If a solvent is used, the nature of the solvent is not critical, and the solvent can suitably be selected from the group consisting of aliphatic and aromatic hydrocarbons, alcohols, esters, ketones, amides, aldehydes, ethers, ionic liquids and sulphoxides, preferably hydrocarbons, more preferably, aromatic hydrocarbons. The use of aromatic hydrocarbon solvents is preferred since the solubility of the eventual benzene compound tends to be high in the aromatic hydrocarbon solvent. Preferably, the aromatic hydrocarbon solvent is toluene, xylene or a mixture thereof.
[0030] In the dehydration and aromatization reaction not only water is split off from the saturated bicyclic ether, but also one molecule of hydrogen per molecule of saturated bicyclic ether is removed during the dehydration and aromatization. It has therefore been considered to employ a dehydrogenation catalyst, in addition to an acidic catalyst that promotes the dehydration. Dehydrogenation catalysts include metal oxides as well as metals, usually on a carrier. Suitable catalysts include chromia and iron oxide as examples of a metal oxide catalyst, and noble metals, such as Pt, Pd, Ru and Rh, on activated carbon as supported metal catalyst.
[0031] Although the use of such catalysts allow for more modest reaction conditions, such as a relatively low temperature, it has been found that the catalyst also promotes the formation of saturated by-products. Without wishing to be bound by any theory, it is believed that hydrogen that is split off from the saturated bicyclic ether to form a benzene compound, is subsequently used to hydrogenate another molecule to form a cyclohexene compound. This reaction is believed to be promoted by a dehydrogenation catalyst.
[0032] When the dehydration and aromatization is carried out in the absence of a solvent, the dehydration and aromatization step is preferably conducted in the presence of a solid acidic catalyst and in the absence of a dehydrogenation catalyst. When a solvent is present in the dehydration and aromatization step, it is suitable to include also a dehydrogenation catalyst.
[0033] The dehydration and aromatization occurs at a reaction temperature that is preferably in the range of 100 to 350° C., preferably from 125 to 275° C. When also a dehydrogenation catalyst and a solvent are present in the reaction mixture, the temperature is suitably somewhat lower, such as from 75 to 250° C., preferably from 100 to 200° C. The atmosphere is typically inert; the reaction is suitably carried out under nitrogen, helium, neon or argon. The pressure in the dehydration and aromatization step is preferably ranging from 0.5 to 50 bar. The saturated bicyclic ether is suitably dehydrated and aromatized in a batch or continuous reactor wherein the residence time is from 0.1 to 48 hours.
[0034] The present process is excellently suited for the preparation of aromatic acids, such as methylphthalic acid or anhydride and hemimellitic acid. It is also possible to prepare other benzene compounds, such as benzene, toluene, xylene, benzoic acid, toluic acid, and similar compounds, in this way. Via this route the provision of these acids or these other benzene compounds from a sustainable source has become available. The furan compound of formula (I) can be prepared from the conversion of carbohydrates, as explained in WO 2013/048248 and WO 2007/104514. Therefore, the present invention also provides the preparation of a substituted benzene compound wherein the benzene compound produced by the dehydration and aromatization of the saturated bicyclic ether is oxidized. In this way the substituents on the benzene compound that contain a carbon atom are converted into carboxylic acid groups.
[0035] The oxidation may be conducted in a known manner. Thereto, the oxidation is suitably accomplished by an oxygen-containing gas in the presence of a catalyst comprising cobalt and manganese or by alkali metal permanganate, such as potassium permanganate, or nitric acid. Aromatic carboxylic acids may suitably be prepared over a catalyst that contains bromine in addition to cobalt and manganese. Preparation of such a catalyst has, for instance, been described U.S. Pat. No. 4,138,354. The oxygen-containing gas may be air, oxygen-enriched air or substantially pure oxygen. When the benzene compound contains an oxygen atom in its substituents, other, more conventional and/or less expensive catalysts are also possible since such benzene compounds are more reactive and easier to oxidize than benzene compounds that do not have an oxygen atom in their substituents. Therefore, oxidation using potassium permanganate, nitric acid, or using oxygen over noble metal-containing catalyst (e.g., Rh, Pd) is also possible.
[0036] The temperature and pressure of the oxidation can be selected within wide ranges. The pressure of the reaction mixture is preferably between 1 and 100 bar, with a preference for pressures between 10 and 80 bar. In case the oxidant is an oxygen-containing gas, such as air, the gas can be continuously fed to and removed from the reactor, or all of the gas can be supplied at the start of the reaction. In the latter case, the pressure of the system will depend on the headspace volume and the amount of gas required for converting the starting material. It is clear that in the latter case, the pressure of the system may be significantly higher than when an oxygen-containing gas is continuously fed and removed.
[0037] The temperature of the reaction mixture at the oxidation is suitably between 60 and 300° C., preferably between 100 and 260° C., more preferably between 150 and 250° C., most preferably between 160 and 220° C.
[0038] In the preferred oxidation catalysts that comprise Co and Mn, molar ratios of cobalt to manganese (Co/Mn) are typically 1/1000-100/1, preferably 1/100-10/1 and more preferably 1/10-4/1.
[0039] Likewise, in these preferred oxidation catalysts, comprising also bromine, molar ratios of bromine to metals (i.e. Br/(Co+Mn)) are typically from 0.001 to 5.00, preferably 0.01 to 2.00 and more preferably 0.1 to 0.9.
[0040] Catalyst concentration (calculated on the metal, e.g., Co+Mn) is preferably between 0.1 and 10 mol % relative to the starting material, with a preference for loads between 2 and 6 mol %. Good results will be obtained in general with catalyst loads of around 4 mol % relative to the starting benzene compound.
[0041] Reaction times suitably range from 0.1 to 48 hours, preferably from 0.5 to 24 hrs. The skilled person will realize that the number of carboxylic groups on the benzene ring may be varied. He may vary this number by selecting the appropriate starting materials. Alternatively, he may want to decarboxylate the products, using a method similar to the one described in U.S. Pat. No. 2,729,674 for the mono-decarboxylation of trimellitic acid. Such decarboxylation involves the application of a relatively high temperature, such as from 200 to 400° C. Since decarboxylation may occur at temperatures of about 200° C., some decarboxylation may already occur when the aromatization of the saturated bicyclic ether is carried out at temperatures of at least 200° C. and when the saturated bicyclic ether contains carboxylic groups as substituents. In the process of the present invention decarboxylation may be used to arrive at the desired benzene compound. By applying longer reaction times and/or higher reaction temperatures, the rate of decarboxylation can be influenced. It was also found that the decarboxylation readily occurs at temperatures from 200° C. when the aromatization is carried out in the absence of a solvent. When a solvent is present in the aromatization step, significantly higher temperatures are required to accomplish significant decarboxylation. Another known decarboxylation process uses a diazabicyclo alkene at elevated temperatures as shown in U.S. Pat. No. 4,262,157.
[0042] The invention enables the provision of certain novel intermediate compounds. Accordingly the present invention provides the hydrogenated Diels-Alder adduct of the formula (III)
[0000]
[0000] wherein X and Y are different and independently selected from the group consisting of hydrogen, alkyl, aralkyl, —CHO, —CH 2 OR 3 , —CH(OR 4 )(OR 5 ), —COOR 6 , wherein R 3 , R 4 and R 5 are the same or different and are independently selected from the group consisting of hydrogen, alkyl, aryl, alkaryl, aralkyl, alkylcarbonyl and arylcarbonyl, or wherein R 4 and R 5 together form an alkylene group, and wherein R 6 is selected from the group consisting of hydrogen, alkyl and aryl; and
wherein R 7 and R 8 are the same or different and are independently selected from the group consisting of sulfonate, —CN, —CHO, and —COOR 9 , wherein R 9 is selected from the group consisting of hydrogen, and an alkyl group, or R 7 and R 8 together form a —C(O)—O—(O)C— group or a —C(O)—NR 10 —C(O)— group, wherein R 10 represents hydrogen, an aliphatic or an aromatic group. The hydrogenated Diels-Alder adduct is an oxa-[2,2,1]-bicyclo-heptane compound.
[0043] More in particular the invention provides a hydrogenated Diels-Alder adduct of formula (IV)
[0000]
[0000] wherein X and Y are different and independently selected from the group consisting of hydrogen, —CHO, —CH 2 OR 3 , —COOR 4 , wherein R 3 is selected from the group consisting of hydrogen, alkyl, aryl, alkaryl, aralkyl, alkylcarbonyl and arylcarbonyl, and wherein R 4 is selected from the group consisting of hydrogen, alkyl and aryl
[0044] It has further been found that the dehydration and aromatization reaction of the saturated bicyclic ether yields a lactone. It is believed that this lactone is an intermediate product in the formation of the eventual benzene compound. This benzene compound can therefore be prepared by subjecting such a lactone to the same reaction conditions as the desired for the formation of the benzene compound from the saturated bicyclic ether. The present invention therefore also provides a lactone compound of formula (V)
[0000]
[0000] wherein Y is hydrogen and X is selected from the group consisting of alkyl, aralkyl, —CHO, —CH 2 OR 3 , —CH(OR 4 )(OR 5 ), —COOR 6 , wherein R 3 , R 4 and R 5 are the same or different and are independently selected from the group consisting of hydrogen, alkyl, aryl, alkaryl, aralkyl, alkylcarbonyl and arylcarbonyl, or wherein R 4 and R 5 together form an alkylene group, and wherein R 6 is selected from the group consisting of hydrogen, alkyl and aryl.
[0045] More preferably, Y is hydrogen and X is selected from the group consisting of alkyl, aryl, alkaryl, aralkyl, —CHO, or —CH 2 OR 3 , wherein R 3 is selected from the group consisting of hydrogen, alkyl and aryl. The alkyl, aryl, aralkyl or alkaryl groups suitably have at most 10 carbon atoms. The alkyl groups may preferably have from 1 to 4 carbon atoms.
[0046] The invention will be illustrated by means of the following examples.
Example 1
Diels-Alder Reaction of (Substituted) Furan and Maleic Anhydride
[0047]
[0048] A round-bottom flask equipped with water-cooled condenser and mechanical over-head stirrer was charged with a furan compound as indicated in Table 1 (1.2 mmol) and maleic anhydride (1.0 mmol). The suspension was stirred at 15-20° C. using a water bath. During the course of the reaction, the mixture turned to a clear homogeneous liquid after a reaction time as indicated in Table 1. Pale-yellow colored crystalline material crystallized from the liquid. The yield was as indicated in Table 1, relative to the molar amount of maleic anhydride. 1 H NMR spectroscopy further revealed the purities of the adducts, as shown in Table 1. Percentages are molar percentages, based on the number of moles of maleic anhydride.
[0049] The results and conditions are shown in Table 1.
[0000]
TABLE 1
Reaction
Yield,
Purity,
Exp. No.
X
Y
time, hr
%
%
1
—H
—H
3
98
94
2
—CH 3
—H
4
>95
93
3
—CH 3
—CH 3
3
96
94
4
—CH 2 —O—CH 3
—H
18
>85
80
5
—CH 2 —O—C 2 H 5
—H
26
>85
80
Example 2
[0050] Hydrogenation of Diels-Alder Adduct from Furan Compounds and Maleic Anhydride
[0000]
[0051] A pressure reactor was charged with 100 parts by weight (pbw) of crude adduct obtained in Example 1 (see Table 2), 2 pbw of catalyst Pd/C (containing 10% wt Pd, based on the catalyst), and THF in a quantity of 5 mL per gram adduct. The reactor was purged 3 times with nitrogen of 4-5 bar, and then pressurized with hydrogen to 80 bar. The reaction mixture was stirred at room temperature at 300 rpm. During the progress of the reaction the hydrogen pressure dropped, but the reactor was subsequently re-pressurized to 80 bar. When the consumption of hydrogen gas stopped, the reaction was completed. The reaction time is indicated in Table 2. Excess hydrogen pressure was cautiously vented off and the reactor was flushed 3 times with nitrogen of 4-5 bar. The mixture was filtered yielding a pale yellow clear solution, which was evaporated to dryness under reduced pressure using a rotary evaporator. The crude product was further purified by recrystallization from methanol or ethyl acetate which resulted in hydrogenated Diels-Alder adduct as colorless solid in a yield and with a purity, as determined by NMR and GC analysis and indicated in Table 2. Percentages are molar percentages, based on starting material (yield) or on product.
[0000]
TABLE 2
Reaction
Yield,
Purity,
Exp. No.
X
Y
time t, hrs
%
%
6
—H
—H
3-5
~100
96
7
—CH 3
—H
3-5
~100
95
8
—CH 3
—CH 3
3-5
~100
98
9
—CH 2 —O—CH 3
—H
5
89
90
10
—CH 2 —O—C 2 H 5
—H
5
85
89
Example 3
Diels-Alder Reaction of Substituted Furan and Methyl Acrylate
[0052]
[0053] A round-bottom flask equipped with water-cooled condenser and mechanical over-head stirrer was charged with a furan compound as indicated in Table 3 (1.2 mmol), methyl acrylate (1.0 mmol) and zinc iodide (0.3 mmol). The suspension was stirred at 40° C. for 48 h. After the completion of reaction, the mixture was diluted with ethyl acetate and washed with 0.1M aqueous solution of Na 2 S 2 O 3 , dried and concentrated to afford pale-yellow colored liquid. The yield was as indicated in Table 3.
[0000]
TABLE 3
Reaction Time
Exp. No.
X
Y
(h)
Yield (%)
11
CH 3
H
48
43
12
CH 3
CH 3
48
45
Example 4
[0054] Hydrogenation of Diels-Alder Adduct from Furan Compounds and Methyl Acrylate
[0000]
[0055] A pressure reactor was charged with 100 parts by weight (pbw) of crude adduct obtained in Example 3 (see Table 4), 2 pbw of catalyst Pd/C (containing 10% wt Pd, based on the catalyst), and THF in a quantity of 5 mL per gram adduct. The reactor was purged 3 times with nitrogen of 4-5 bar, and then pressurized with hydrogen to 80 bar. The reaction mixture was stirred at room temperature at 300 rpm. During the progress of the reaction the hydrogen pressure dropped, but the reactor was subsequently re-pressurized to 80 bar. When the consumption of hydrogen gas stopped, the reaction was completed. The reaction time is indicated in Table 4. Excess hydrogen pressure was cautiously vented off and the reactor was flushed 3 times with nitrogen of 4-5 bar. The mixture was filtered yielding a pale yellow clear solution, which was evaporated to dryness under reduced pressure using a rotary evaporator. The crude product was further purified by a short filtration through silica gel affording hydrogenated Diels-Alder adduct, an oxa-bicyloheptane compound with a methylcarboxylate substituent on the 2- or 3-position, as pale-yellow coloured liquid.
[0000]
TABLE 4
Reaction Time
Exp. No.
X
Y
(h)
Yield (%)
13
CH 3
H
12
90
14
CH 3
CH 3
12
92
Example 5
Aromatization of Hydrogenated Diels-Alder Adduct Over Acid and Dehydrogenation Catalysts
[0056]
[0057] A stainless steel pressure reactor was charged with the products obtained in experiments 7 and 8 of Example 2 (see Table 2) (1.0 mmol), an acid zeolite Y catalyst in an amount of 50 pbw per 100 pbw of the product of experiments 7 and 8 of Example 2, respectively, 3 pbw of Pd/C (10 wt % of Pd based on the weight of the catalyst) and toluene (20 mL/g product). Next, the reactor was purged 3 times with nitrogen of 10 bar, and the reaction mixture was stirred (750 rpm) at 150-200° C. for 24 h. During the course of reaction, the pressure rose to a maximum of 6-8 bar. After completion of the reaction, the reactor was cooled down to room temperature and the excess pressure was carefully vented off. The crude reaction mixture was filtered using a filter aid and washed 5 times with 10 mL toluene, giving a pale yellow clear solution, which was then evaporated to dryness under reduced pressure using a rotary evaporator to give yellow colored crystalline material. The analysis of crude product using 1 H NMR spectroscopy confirmed the formation of desired aromatic compound, viz. optionally substituted phthalic anhydride together with up to four different by-products (based on the catalyst used). The products distribution was calculated by NMR analyses, using 1,4-dinitrobenzene as internal standard.
[0058] The yields of the respective products are shown in Table 5. Percentages are molar percentages, based on starting material.
[0000]
TABLE 5
Exp.
Acid
Dehydrog.
Yield of Product, %
No.
X
Y
catalyst
Catalyst
1
2
3
4&5
6
15
—CH 3
—CH 3
H—Y
Pd/C
67
—
—
12*
—
16
CH 3
—H
H—Y
Pd/C
59
0
0
21
—+
*in this case, it is para-xylene.
+any toluene formed was not detectable as the reaction was performed in toluene as solvent
Example 6
Aromatization of Hydrogenated Diels-Alder Adduct Over Acid Catalyst
[0059] In experiment Nos. 17 and 18 a round-bottom flask was charged with each of the products obtained in Example 4 (1.0 mmol) and solid acid catalyst (100 pbw per 100 pbw of product). The acid catalyst was selected from an acid zeolite Y with a silica-alumina ratio of 5.2 (“H—Y”). Next, the flask was purged 3 times with nitrogen and inserted into a glass oven at 200° C. The reaction flask was rotated at 25 rpm for about 2.0 hr under nitrogen atmosphere. After completion of the reaction, the glass oven was cooled down to room temperature. The crude reaction mixture was dissolved in chloroform (CDCl 3 ) and filtered and washed 3 times with 10 mL CDCl 3 , giving a pale yellow clear solution, which was then evaporated to dryness under reduced pressure using a rotary evaporator. A yellow colored crystalline material was thus obtained. The analysis of crude product using 1 H NMR spectroscopy confirmed the formation of desired benzene compound, i.e. the benzene compound with a carboxylate moiety on the 2- or 3-positon, and the calculated product yield about was 20-30% molar.
Example 7
Solvent-Free Aromatization of Hydrogenated Diels Alder Adduct Over Acid Catalyst
[0060]
[0061] A round-bottom flask was charged with a product obtained in Example 2 (1.0 mmol) and solid acid catalyst (100 pbw per 100 pbw of product). The acid catalyst was selected from an acid zeolite Y with a silica-alumina ratio of 5.2 (“H—Y”), such zeolite Y catalyst that contained 1% wt Pd (“Pd/H—Y”), such zeolite Y catalyst that contained 0.25% wt Pt and 0.25% wt Pd (“Pt/Pd/H—Y”). Next, the flask was purged 3 times with nitrogen and inserted into a glass oven at 200° C. The reaction flask was rotated at 25 rpm for about 2 to 3 hr under nitrogen atmosphere. After completion of the reaction, the glass oven was cooled down to room temperature. The crude reaction mixture was dissolved in chloroform (CDCl 3 ) and filtered and washed 3 times with 10 mL CDCl 3 , giving a pale yellow clear solution, which was then evaporated to dryness under reduced pressure using a rotary evaporator. A yellow colored crystalline material was thus obtained. The analysis of crude product using 1 H NMR spectroscopy confirmed the formation of desired aromatic compound, viz. optionally substituted phthalic anhydride together with up to three different by-products (dependent on the catalyst used). The product distribution in the crude mixture was calculated by NMR analyses using 1,4-dinitrobenzene as internal standard.
[0062] The compounds, the catalyst used, and the yields of the respective products are shown in Table 7. Percentages are molar percentages, based on starting material.
[0000]
TABLE 7
Exp.
Acid
Yield of Product, %
No.
X
Y
catalyst
1
2
3&4
5
19
—H
—H
H—Y
41
—
26
23
20
—CH 3
—H
H—Y
76
—
13
—
21
—CH 3
—CH 3
H—Y
72
—
11
17
22
—CH 3
—H
Pd/H—Y
80
—
7
—*
23
—CH 3
—H
Pt/Pd/H—Y
62
—
17
—**
*Experiment 22 also yielded 5% of 3-methyl-1,2-dicarboxylic anhydride-cyclohexene-1.
**Experiment 23 also yielded 10% of 3-methyl-1,2-dicarboxylic anhydride-cyclohexene-1.
Example 8
Effect of Time and Temperature on the Aromatization of Saturated Bicyclic Ether Over Acid Catalyst
[0063]
[0064] A round-bottom flask was charged with a product obtained in Example 2 (1.0 mmol) and solid acid catalyst (50 pbw or 100 pbw per 100 pbw of product). The acid catalysts used were the same as those used in Example 7. Next, the flask was purged 3 times with nitrogen and inserted into a glass oven at a fixed temperature. The reaction flask was rotated at 25 rpm for a fixed amount of time under nitrogen atmosphere. Subsequently, the glass oven was cooled down to room temperature. The crude reaction mixture was dissolved in chloroform (CDCl 3 ) and filtered and washed 3 times with 10 mL CDCl 3 , giving a pale yellow clear solution, which was then evaporated to dryness under reduced pressure using a rotary evaporator. A yellow colored crystalline material was thus obtained. The analysis of crude product using 1 H NMR spectroscopy confirmed the formation of desired aromatic compound, viz. optionally substituted phthalic anhydride together with up to three different by-products (dependent on the catalyst used). The product distribution in the crude mixture was calculated by NMR analyses using 1,4-dinitrobenzene as internal standard.
[0065] The compounds, the catalyst used, and the yields of the respective products are shown in Table 8. Percentages are molar percentages, based on starting material.
[0000]
TABLE 8
Exp.
Temp.
Time
Acid
Conv.
Yield of Product, %
No.
X
Y
(° C.)
(hrs)
catalyst
(%)
1
2
3&4
5
24
—CH 3
—H
150
2
H—Y (50%)
89
12
77
0
0
25
—CH 3
—H
150
15
H—Y (50%)
100
34
66
0
0
26
—CH 3
—H
160
2
H—Y (50%)
100
24
76
0
0
27
—CH 3
—H
175
2
H—Y (50%)
100
37
63
0
0
28
—CH 3
—H
160
2
H—Y (100%)
100
43
54
0
0
29
—CH 3
—H
175
2
H—Y (100%)
100
81
9
6
0
30
—CH 3
—H
200
2
H—Y (100%)
100
76
0
6
13
31
—CH 3
—H
225
2
H—Y (100%)
100
45
0
0
55
32
—CH 3
—H
250
5
H—Y (100%)
100
0
0
0
100
33
—H
—H
160
15
H—Y (100%)
43
15
28
0
0
34
—H
—H
200
2
H—Y (100%)
100
41
0
26
23
35
—CH 3
—CH 3
200
2
H—Y (100%)
100
72
0
11
17 | A benzene compound is prepared by reacting a furan compound to produce an unsaturated bicyclic ether having an unsaturated carbon-carbon bond; hydrogenating the unsaturated carbon-carbon bond in the unsaturated bicyclic ether to produce a saturated bicyclic ether; and dehydrating and aromatizing the saturated bicyclic ether to produce the benzene compound. | 2 |
BACKGROUND OF THE INVENTION
As a result of the increased usage of built-in appliances, such as dishwashers, compactors, surface mounting cooking units, and other appliances built into cabinet counters, the area of the counter has been gradually reduced over the years. To further complicate the situation, the cabinet counter into which the sink was installed, prior to the occurence of plywood and particleboard, was from 26 to 27 inches in depth. However, as plywood and particleboard have now become the common cabinet materials in use today, and are manufactured in 48 inch widths, it is common practice of cabinet makers to rip each 48 inch sheet into two strips 24 inches in width to serve as cabinet counters. From this cabinet counter of 24 inches width must be deducted 3/4 of an inch for the cabinet front thickness, 3/4 of an inch for the cabinet overhang, and at times 3/4 of an inch for the cabinet counter back splash. The remaining surface depth of the cabinet counter available for installation of a sink, commonly 21 inches in width, is 213/4 inches.
As a result of the diminshed counter top area, it has become increasingly difficult to install and tighten known clamps which require a counter underside to bear against. Furthermore, the prior art sink rim clamps are designed only to accommodate a cabinet counter thickness of 3/4 of an inch. It is, however, not uncommon to encounter a cabinet counter 11/2 inches in thickness at the points where the rim clamps are to be installed. As a result of the above stated inconveniences the installer must oftimes chisel notches into the cabinet front and sides, as well as into the underside of the cabinet counter to facilitate the installation of rim securing clamps utilized in prior art installation procedures thus increasing the cost of sink installation. Also proximity of cabinet partitions and front to the counter openings is often such that the installer is unable to attach and secure the clamps to the counter underside.
SUMMARY OF THE PRESENT INVENTION
The present invention is embodied within sink mounting means for securement to a cabinet counter for retention of a subsequently installed sink.
The present mounting means includes members of angular section for securement in either a continuous or non-continuous manner to a counter edge defining an opening for sink reception. In distinction to the prior art type of clamps wherein the sink is supported by a surface trim ring or frame, the present sink mounting means includes straight and/or curved elongate members of angular section for securement to the counter prior to sink installation. The prior art clamps in common use are installed while supporting sink weight making the installation extremely awkward and even risky as sinks may fall on the installer during installation efforts. In distinction to prior art trim rings, the surface trim ring assembly of the present invention is not a load bearing member thus permitting convenient installation of same.
In one form of the present invention, the mounting means is preliminarily formed into a closed or frame type configuration. Other versions of the invention include straight or curved members or a combination of both with or without adjustable bars therebetween. Accordingly the invention in a non-adjustable form may be of a size to accommodate a common sink size, for example, 21 inches by 32 inches. Interchangeable lockable adjustment bars usable with other forms of the invention permit the present mounting components to be formed into a closed frame to accommodate a very wide range of sink sizes. Locking means are provided to enable complete assembly and locking of the mounting means to a sink accommodating size prior to attachment to the inner periphery of the counter sink opening. The mounting means, during such installation, is highly accessible to the installer and bears no sink load during installation to greatly facilitate installation.
Important objects of the present invention include sink mounting means closely confined adjacent the inner marginal area of the counter opening so as to not conflict with below counter encumbrances such as adjacent, partitions walls and appliances; mounting means permitting sink removal simply by lifting of same away from sink support members to accordingly facilitate sink removal and replacement or reinstallation after the application of new counter top material; mounting means permitting the sink to be operational without a surface trim ring in order that same may be applied lastly in a new home to avoid damage by construction workers; mounting means accommodating a wide range of sink sizes and any counter top thickness while requiring a relatively low inventory of components; mounting means which avoids chipping or crazing of sink surfaces; mounting means enabling the use of other than steel surface trim rings which may be of lightweight colored plastic as they are not load bearing; mounting means greatly reducing sink installation time and risk of injury.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIG. 1 is a plan view of a sink or lavatory installed using the present mounting means;
FIG. 2 is a vertical sectional view of the mounting means taken along the line 2--2 of FIG. 1;
FIG. 3 is a plan view of FIG. 2;
FIG. 4 is a view similar to FIG. 2 showing a modified form of the mounting means;
FIG. 5 is an enlarged plan view of that area circled at 5 in FIG. 1 with fragments broken away for purposes of illustration;
FIG. 6 is a plan view of a segment of sink mounting means relieved to permit forming of a corner segment;
FIG. 7 is a vertical sectional view of the present sink mounting means including an adapter clip enabling use of the mounting means with a tile covered counter;
FIG. 8 is a fragmentary plan view of a counter top with an adjustable form of the present mounting means in place thereon about a sink receiving counter opening;
FIG. 9 is a vertical sectional view taken along line 9--9 of FIG. 8;
FIG. 10 is a vertical sectional view taken along line 10--10 of FIG. 8;
FIG. 11 is a composite plan view of different sized adjustment bars terminating along their respective center lines;
FIG. 12 is a plan view of elongate sink mounting means intended for use without an associated curved member;
FIG. 13 is a plan view of elongate curved mounting means for use in the installation of a curved or oval sink;
FIG. 14 is a vertical sectional view of the present mounting means modified for installation of a stainless steel sink.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With continuing attention to the accompanying drawings, the reference numeral 1 indicates the top surface of a cabinet counter of the type found in kitchens and bathrooms. Characteristically such counter tops receive an overlying protective layer of material as at 2, such commonly being of a durable synthetic plastic or ceramic material. A counter sink opening is defined by a continuous counter edge 1A which is offset from the perimetrical edge of a sink flange 3A of a sink or lavatory 3.
The present sink mounting means includes, in one form, a continuous frame member 10 of angular section secured in abutment against cabinet edge 1A such securement being as by threaded fasteners as at F in FIG. 2. A suitable adhesive may be utilized if so desired. Said angular member comprises an upright web 12 and an inwardly directed flange at 13. An upper flange at 11 restingly engages the counter top to facilitate attachment of the present mounting means to the counter edge. As the present mounting means does not engage the underside of counter 1, the thickness of said counter is importantly of no concern. Accordingly the installer is not confronted with unexpected counter thicknesses resulting in various installation problems, as earlier mentioned, experienced with other sink mounting arrangements.
Inwardly directed flange 13 is adapted to receive a sink support member at 14 the upper surface 14A of which receives the sink flange 3A in a rested manner. Sink support member 14 is preferably of an elastomeric nature preferably a neoprene rubber block but which may otherwise be embodied of a rigid material. Said sink support member is frictionally confined between oppositely disposed walls 15 and 16 integral with flange 13. The vertical dimension of support member 14 will obviously vary in accordance with the thickness of sink flange 3A with the objective being the upper surface of the sink flange being positioned substantially coplanar with the upper surface of counter 1.
A surface trim ring assembly is indicated generally at 17 which includes a continuous ring member 18 which conventionally overlies a marginal area of sink flange 3A and a marginal area of counter 1 to conceal the gap between the sink flange and counter edge. Said ring is provided on its underside with spaced apart anchor bolts 20, each held by a plate 19 slidably and pivotally receiving a horizontally turned upper end 20A of the bolt. The surface trim ring 18 is biased downwardly by means of a nut element 21. To assure a watertight seal between the trim ring and sink flange 3A and the counter top surface, peripheral beads 22 and 23 of a sealant such as neoprene are applied to the ring. The trim ring assembly 17 is the last component installed of the present mounting means and entails the downward insertion of the lower ends of bolts 20 through bolt receiving openings 13A in flange 13. Said openings may be somewhat elongated to facilitate insertion.
In FIG. 5 a curved or corner segment of member 10 is shown wherein flange portions of said member 10 are shown cut away enabling the bending of said member into curved configuration. With attention to FIG. 6, a cut or punched out segment of inwardly directed flange 13 is shown in phantom lines at 25 to indicate that portion removed while, similarly, a portion of upper flange 11 is indicated in phantom lines at 26. Web 12 may then be shaped on a radius corresponding to that of the counter corner normally 13/4 inches. Obviously the configurations of cutout portions 25 and 26 will vary in accordance to suit the radius of the counter corner.
As shown in FIG. 7, an angular clip C may be utilized to receive a web attaching fastener F.
With attention to FIG. 4, an alternative sink support member is disclosed in the form of a leveling bolt 27 in threaded engagement with an opening 28 in a modified inwardly directed flange 13'. Other components of the surface trim ring assembly and the sink of FIG. 4 are identified by prime reference numerals which correspond to reference numerals identifying similar parts in the first form of the invention. In the present modification, the sink rim 3A' is at all times only in rested engagement with the upper end of leveling bolts 27 and accordingly the sink is not susceptible to severe fastener loads as encountered by other sink mounting arrangements which can crack or craze sink surfaces.
With attention now to FIGS. 8, 9, 10 and 11, the mounting means shown therein is adjustable for various sink sizes and comprises spaced apart straight and curved or corner members of angular section interconnected by adjustment bars. A cabinet counter upper surface is again indicated at 1 with a sink receiving opening defined therein by a counter peripheral edge 1A. Elongate members of angular section are indicated at 30 with adjustment bars 30A both members 30 typically shown in section in FIG. 9. Other angular members at 31 and 32 (FIG. 11) are of other lengths as are the adjustment bars 31A, 32A associated therewith the use of a specific combination of said members being determined by the sink size being installed. In FIG. 8, angular members 30 and their adjustment bars 30A are utilized to vary both length and width of the present mounting means, however, it will be understood that various combinations of members will be used to accommodate the length and width of the sink being installed. For example, angular members at 31 and 32 are of different lengths and are fully interchangeable with angular members 30 in FIG. 8 to comprise a mounting for a different sink size. The adjustment bars shown associated with each of said angular members may be secured to their respective member by spot welding or the like within a channel as at 33 (FIG. 9) defined by inwardly directed flanges 34 and 35 of the member. Flange 34, in similarity to the first form of the invention has a pair of upstanding walls 36, 37 between which is securely confined an inserted sink support member 38 of the type earlier mentioned. Inwardly directed flanges 34, 35 have aligned apertures 39 and 40 formed therein at intervals to receive a bolt 20 of a surface trim ring assembly of the type earlier described but, of course, of a different size and with different bolt spacing. As the spacing of surface trim ring bolts 20 varies with the size of the surface trim ring it is necessary to provide the elongate angular members 30-32 with apertures 31B and 32B at different intervals as shown. The adjustment bars 30A-32A associated with each angular member 30-32 are correspondingly apertured for bolt reception. Each elongate angular member 30-32 additionally includes a web 42 and an upper flange 43 the latter for counter top engagement with the web being secured in the aforementioned manner.
The FIG. 8 version of the present invention includes a plurality of curved members of angular section a pair of which are indicated generally at 45 and 46 which are similar to that curved segment of the first form of the invention shown in FIG. 5. Each curved section includes a pair of straight portions typically shown in cross section in FIG. 10. For economy of manufacture members 30-32 and 45, 46 may be formed from the same stock preferably extruded aluminum.
With attention to FIG. 10, the curved members 45, 46 include inwardly directed flanges 47 and 48 spaced to provide a channel 50 for reception of an adjustment bar 30A-32A. For locking of the adjustment bars to a curved member, locking pins at 51 are provided each having a head and shank for flush insertion into flange apertures 47A and 48A and through an aperture 52 in the adjustment bar provided at one inch intervals. Accordingly the completely formed, rigid sink mounting means may be assembled into a unitary structure prior to setting of same into place and securement within the counter opening. The curved members of angular section 45,46 include a web as at 53 and an upper flange 54 for counter top engagement with the web being attached to the counter edge 1A as earlier described in the first form of the invention.
Sink support members 38 are received within walls 55, 56 on inwardly directed flange 47. Said flange is apertured at 57 (FIG. 8) for the reception of a trim ring assembly bolt 20.
In FIGS. 12 and 13, I show sink members of angular section of both straight and arcuate configuration respectively both similar in section to the first described form of the invention as shown in FIG. 2 and intended for use without corner members as such. For example, the straight member indicated generally at 60 is secured in place as earlier mentioned to a straight edge 1A of counter 1 while in FIG. 13 a curved member indicated generally at 61 is intended for use in mounting a sink of round or elliptical configuration.
In FIG. 14, a further modification is shown wherein the sink support member of angular section 63 is adapted to receive a bolt 65 the head 65A of which is carried within an inverted sink channel 62 integral with the steel sink flange 66A of a sink 66. Such sinks normally engage the counter top and do not require a separate surface trim ring. The member of angular section may be the same as the section shown in FIG. 9, or it may be similar to the section shown in FIG. 2 with the inserted member dispensed with. Bolt 65 is provided with a first nut 67 engaging the underside of channel 62 and a second nut 68 to draw the sink flange 63 into secure engagement.
In use, the sink opening is cut into the counter top 1 in the normal manner. If the sink is of a common size, the first described form of sink mounting means may be pre-formed and thence set into the opening and fastened to the counter edge. Sink support members are of a selected height to position the sink flange 3A to the desired level and the sink thereafter set into place whereafter the outlet is connected to provide an operable sink or lavatory. The trim ring assembly is installed lastly to avoid damage to same as can occur in a new home from other construction efforts.
In the adjustable form of the invention, viewed in FIGS. 8 through 11, additional steps are required, that of selecting the proper angular member 30-32 to suit the length and width of a sink such being other than a common size. The sink mounting means will be assembled and locked in the desired configuration by locking pins 51 insertable through adjustment bar openings 52 and aligned openings 47A-48A in curved members 45,46 whereafter the sink mounting means is installed.
The trim ring assembly 17 is installed lastly by insertion of assembly bolts 20 being downwardly inserted through somewhat enlarged opeings in the inwardly directed flanges of the members of angular section for subsequent securement by the application of nut elements 21.
While I have shown but a few embodiments of the invention it will be apparent to those skilled in the art that the invention may be embodied still otherwise without departing from the spirit and scope of the invention. | Sink mounting means utilizing a member of angular cross section having a web for securement to a cabinet counter edge. A sink support member is carried by an inwardly directed flange of the member of angular section which member may be of a closed frame type configuration, straight or of curved configuration with or without adjustment bars extending therebetween to lock the members in a unitary, fixed relationship to facilitate attachment of the mounting means to the counter edge which is done independently from the later inserted sink or lavatory. | 4 |
FIELD OF THE INVENTION
[0001] This invention relates to the field of personal computers, usually referred to as laptops, and, more particularly, to the carrying case used for manual transport.
BACKGROUND OF THE INVENTION
[0002] Since 9/11, the world of public transportation has changed significantly. In fact, there is now a government agency, the Transportation Security Agency (TSA), that is responsible for the heightened security at airports and other facilities. The security measures taken by TSA personnel to check each passenger and all packages carried on board airplanes has resulted in long lines and increased pre-flight boarding times.
[0003] While the TSA personnel use sophisticated instruments to determine the absence of illegal compounds and objects, there remains a requirement for visual inspection of certain devices. Packages, boxes, carry-on bags must be opened for such visual inspections. Because the airlines have been permitting the passengers to carry on just about anything, opening and closing of these articles adds to the delays of clearing security points.
[0004] The laptop computer has become a normal accessory for many travelers, both for work and entertainment, during the trip. The conventional laptop has no integrated carrying devices and, therefore, usually is placed in a carry case. Most cases have various pockets and compartments to carry peripheral equipment and other things the owner may include with the computer. The carrying cases may be made of soft or hard materials which may be padded and completely enclose the computer for protection.
[0005] Akins, U.S. Pat. No. 6,149,001, discloses a carry case made of thin flexible material with pockets that fits about a laptop like a glove. The case has openings for attaching power cords and other peripherals but completely encloses the computer.
[0006] U.S. Pat. No. 5,775,497 to Krulik discloses a cradle for a laptop that has two major planar pads connected by Velcro tabs. The pads are placed on each side of the computer for protewction during movement.
[0007] Holter et al, U.S. Pat. No. 6,164,505, discloses a harness with shoulder straps and waist belt that can be attached to a rigid case for carrying the case. Certain modifications of the case are required to provide attachment points for the harness.
[0008] Therefore, what is needed is a device for carrying a laptop computer that permits visual identification and is easily mounted and dismounted from the computer.
SUMMARY OF THE INVENTION
[0009] The instant invention is a carrying case for use in combination with a laptop computer. The carrying case permits visual inspection of the computer by use of a case formed from webbing having a plurality of longitudinal elements extending along the edges of the computer and a plurality of horizontal tapes extending across the width of the computer. Each of the longitudinal elements and horizontal tapes have opposite ends, the longitudinal elements are perpendicular to the horizontal tapes and are connected together at the opposite ends. A carrying handle is connected to each of the horizontal tapes whereby the longitudinal elements may be folded approximately in half about the computer to place said the horizontal tapes adjacent to each other and presenting said carrying handles to be gripped by one hand.
[0010] Thus, an objective of this invention is to provide a lightweight webbing for carrying a laptop that would allow travelers to simply place the laptop on the moving belts of the security machines in airports and retrieve them without having to open any bags, pockets or other containers.
[0011] Another objective of this invention is to provide a one piece harness which includes carrying handles that can be attached to a laptop without any modifications of the computer case or use of any tools.
[0012] Still another objective of this invention is to provide a carrying case that allows opening of the computer without removal from the webbing.
[0013] A further objective of this invention is to provide a harness that allows the use of the computer without removal.
[0014] Other objectives and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] [0015]FIG. 1 is a perspective of a laptop contained within the webbing of this invention;
[0016] [0016]FIG. 2 is a top plan view of this invention; and
[0017] [0017]FIG. 3 is a detail view of elastic fasteners for attaching the webbing to a laptop.
DETAILED DESCRIPTION
[0018] Although the invention will be described in terms of a specific embodiment, it will be readily apparent to those skilled in this art that various modifications, rearrangements and substitutions can be made without departing from the spirit of the invention.
[0019] In FIG. 1, the webbing 10 is shown attached to a laptop 11 with the carrying handles 12 and 13 positioned to be gripped by the user. The webbing 10 may be of any suitable material having the requisite strength and non-toxic properties to electronic parts and human contact. For example, leather, polyethylene, cellulose acetate, rayon or nylon webbing may be used though any other polymer may be suitable. The webbing may be woven, knitted or film with or without apertures in the film. The webbing 10 fits about the laptop 11 in a manner that leaves the normal portals free from obstruction to permit use of the computer.
[0020] As seen in FIG. 2, the harness or webbing 10 is formed in a rectangular grid. The longitudinal elements 14 are connected to horizontal tapes 15 at each cross over point 16 . The connections 16 may be mechanical fasteners, such as brads, grommets, or stitches, or chemical, such as adhesives, autologous bonding by heat and pressure or solvents, or combinations thereof. The longitudinal elements and the horizontal tapes may be integrally molded or otherwise formed. The left marginal longitudinal element 17 is connected at one end to an end of a horizontal tape 18 which extends perpendicular to the element 17 . The other end of the marginal longitudinal element 17 is connected to an end of another horizontal tape 19 . The right marginal longitudinal tape 20 is connected at one end to the other end of horizontal tape 18 and at the other end to horizontal tape 19 . The horizontal tapes are shorter than the longitudinal elements resulting in a rectilinear form.
[0021] Carrying handles 12 and 13 are formed by a loop of webbing with left longitudinal portion 21 and right longitudinal portion 22 parallel with left and right marginal longitudinal elements 17 and 20 . The left portion 21 and the right portion 22 are connected to the horizontal tapes 18 and 19 at the cross over points.
[0022] Near the center of the left and right marginal longitudinal elements 17 and 20 , a pair of bottom tapes 23 and 24 extend perpendicularly to the longitudinal elements and the left and right longitudinal portions of the carrying handles. The bottom tapes are connected to the marginal elements and the carrying handles at the cross over points. The bottom tapes 23 and 24 are located on opposite sides of an imaginary center line bisecting the marginal longitudinal elements. The spacing between the tape 23 and the tape 24 is approximate to the thickness of a laptop folded for carrying. The bottom tape 31 is disposed inside the closed computer during transport.
[0023] While the marginal longitudinal elements and the left and right longitudinal portions of the carrying handles have been described as continuous, it is possible that the area between the bottom tapes 23 and 24 could be reinforced or made of a different material.
[0024] The harness 10 is mounted on the laptop by elastic loops 25 , 26 , 27 and 28 located at the four corners of the rectilinear form. The elastic loops are oriented at approximate 45 degrees angle to the four corners. The opposite ends 29 and 30 of the elastic loops are each connected to a marginal longitudinal element and a horizontal tape. The materials of the elastic loops may be the same as the webbing and the connection to the webbing may be the same as used in the webbing.
[0025] It is to be understood that while I have illustrated and described certain forms of my invention, it is not to be limited to the specific forms or arrangement herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown in the drawings and described in the specification. | A carrying case for a computer is made of webbing to permit security personnel to view the computer without removing it from the case. The laptop can be opened and used without removing the case. | 0 |
RELATED APPLICATIONS
[0001] This application is a continuation application of U.S. patent application Ser. No. 13/008146, filed Jan. 18, 2011, entitled, “BIOSENSOR, BIOSENSOR PACKAGE STRUCTURE HAVING SAME, AND METHOD FOR FABRICATING SAME,” which claims all benefits accruing under 35 U.S.C. §119 from China Patent Application No. 201010521439.0, filed on Oct. 27, 2010 in the China Intellectual Property Office.
BACKGROUND
[0002] 1. Technical Field
[0003] The present disclosure relates to a biosensor with electrodes comprising a plurality of carbon nanotubes, a biosensor package structure having the same, and a method for fabricating the same.
[0004] 2. Description of Related Art
[0005] In general, a biosensor is a device that uses a specific biological element or a physical element similar to the biological element to get information from a measured object. The detected information is usually transduced by the biosensor into recognizable signals such as colors, fluorescence, or electrical signals. With technical advances in modem science, a biosensor is one of the devices that have developed rapidly.
[0006] A biosensor is composed of a receptor which reacts with a measured object to be detected, and electrodes which transmit current variation generated by the reaction between the receptor and the measured object. Examples of the receptor include an enzyme, antibody, antigen, membrane, receptor, cell, tissue, and deoxyribonucleic acid (DNA), which selectively reacts with the measured object. The electrodes are usually metal electrodes.
[0007] However, a width of each of the metal electrodes in the above-described biosensor is in a range from several micrometers (um) to dozens of micrometers. Thus, an amount of electrodes in a unit area of the biosensor is too few to influence accuracy and sensitivity of the same. Furthermore, the metal electrodes with poor inoxidability will shorten a lifetime of the biosensor.
[0008] Thus, there remains a need for providing a new biosensor which has greater accuracy, sensitivity, and a longer lifetime.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Many aspects of the disclosure can be better understood with reference to the drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the views.
[0010] FIGS. 1 , 2 , and 3 are schematic views of embodiments of a biosensor.
[0011] FIG. 4 is a schematic view of an embodiment of a biosensor package structure.
[0012] FIGS. 5 , 6 , 7 , 8 , and 9 show different schematic views of processes to manufacture a plurality of biosensors.
DETAILED DESCRIPTION
[0013] The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one.
[0014] According to one embodiment, a biosensor 120 as illustrated in FIG. 1 comprises a base 180 with a surface, two electrodes 1210 and 1220 , and a receptor 1230 . The two electrodes 1210 and 1220 are illustrated as a first electrode 1210 and a second electrode 1220 for exemplification and should not be treated as a limitation. The first electrode 1210 , the second electrode 1220 , and the receptor 1230 are located on the surface of the base 180 with an interval.
[0015] The first electrode 1210 comprises a first lead 1212 and a plurality of first carbon nanotubes 1214 . The first carbon nanotubes 1214 are substantially parallel to each other, and comprise a first probe 1216 . The first lead 1212 is electrically connected to one side of each of the first carbon nanotubes 1214 and an external circuit (not shown).
[0016] Similarly, the second electrode 1220 comprises a second lead 1222 and a plurality of second carbon nanotubes 1224 . The second carbon nanotubes 1224 are substantially parallel to each other, and comprise a second probe 1226 . The second lead 1222 is electrically connected to one side of each of the second carbon nanotubes 1224 and an external circuit (not shown).
[0017] The first carbon nanotubes 1214 and the second carbon nanotubes 1224 can be single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes, or combinations thereof. The diameter of the single-walled carbon nanotubes can be in the range from about 0.5 nanometers (nm) to about 50 nm. The diameter of the double-walled carbon nanotubes can be in the range from about 1 nm to about 50 nm. The diameter of the multi-walled carbon nanotubes can be in the range from about 1.5 nm to about 50 nm. In one embodiment, the length of the first carbon nanotubes 1214 and the second carbon nanotubes 1224 can be in a range from about 10 micrometers (um) to about 50 um.
[0018] More specifically, the first carbon nanotubes 1214 respectively correspond to the second carbon nanotubes 1224 . Thus, the first probe 1216 of each of the first carbon nanotubes 1214 corresponds to the second probe 1226 of each of the second carbon nanotubes 1224 . A distance between each two first carbon nanotubes 1214 is in a range from about 5 um to about 10 um. Similarly, a distance between each two second carbon nanotubes 1224 is in a range from about 5 um to about 10 um. A distance between the first probe 1216 of each of the first carbon nanotubes 1214 and the second probe 1226 of each of the second carbon nanotubes 1224 is equal to or less than 10 um. Furthermore, as shown in FIG. 1 , an extended direction of each of the first carbon nanotubes 1214 is substantially parallel to an extended direction of each of the second carbon nanotubes 1224 .
[0019] The first lead 1212 and the second lead 1222 can be conductive thick liquid, metal, carbon nanotubes, indium tin oxide (ITO), or any combination thereof. In one embodiment, the first lead 1212 and the second lead 1222 are made by printing or plating the conductive thick liquid. The conductive thick liquid comprises powdered metal, powdered glass with a low fusion point, and binder. The powdered metal is powdered silver. The binder is terpineol or ethyl cellulose. A weight percentage of the powdered metal is in a range from about 50% to about 90%. A weight percentage of the powdered glass with a low fusion point is in a range from about 2% to about 10%. A weight percentage of the binder is in a range from about 8% to about 40%.
[0020] The receptor 1230 comprises a plurality of carriers 1232 and a plurality of sensing materials 1234 . The sensing materials 1234 are embedded in each of the carriers 1232 . The first probe 1216 of each of the first carbon nanotubes 1214 and the second probe 1226 of each of the second carbon nanotubes 1224 are covered by the receptor 1230 , such that the first electrode 1210 and the second electrode 1220 are electrically connected to each other. More specifically, the carriers 1232 define a plurality of conductive circuits, between the first carbon nanotubes 1214 of the first electrode 1210 and the second carbon nanotubes 1224 of the second electrode 1220 , to electrically connect the sensing materials 1234 .
[0021] The carriers 1232 can be carbon nanotubes, carbon fibers, amorphous carbon, graphite, or any combination thereof. In one embodiment, the carriers 1232 are carbon nanotubes with a plurality of functional groups. The functional groups can be carboxyl (—COOH) groups, hydroxyl (—OH) groups, aldehyde (—CHO) groups, amino (—NH2) groups, or any combination thereof.
[0022] In testing, the sensing materials 1234 embedded in the carriers 1232 react to a measured object such that current of the biosensor 120 is varied. The current variation of the biosensor 120 is transmitted by the first carbon nanotubes 1214 and the first lead 1212 . Alternatively, the current variation of the biosensor 120 is transmitted by the second carbon nanotubes 1224 and the second lead 1222 . The sensing materials 1234 can be antibodies, antigens, DNA, or any combination thereof. In one embodiment, the sensing materials 1234 are antibodies.
[0023] According to another embodiment, a biosensor 120 as illustrated in FIG. 2 comprises a base 180 with a surface, a first lead 1212 , a plurality of first carbon nanotubes 1214 , a second lead 1222 , and a plurality of second carbon nanotubes 1224 . Each of the first carbon nanotubes 1214 comprises a first probe 1216 , and each of the second carbon nanotubes 1224 comprises a second probe 1226 . Furthermore, as shown in FIG. 2 , the first carbon nanotubes 1214 substantially parallel to each other and the second carbon nanotubes 1224 substantially parallel to each other form a specific angle.
[0024] According to still another embodiment, a biosensor 120 as illustrated in FIG. 3 comprises a base 180 with a surface, a first lead 1212 , a plurality of first carbon nanotubes 1214 , a second lead 1222 , and a plurality of second carbon nanotubes 1224 .
[0025] Each of the first carbon nanotubes 1214 comprises a first probe 1216 , and each of the second carbon nanotubes 1224 comprises a second probe 1226 . Furthermore, as shown in FIG. 3 , an extended direction of each of the first carbon nanotubes 1214 is substantially perpendicular to an extended direction of each of the second carbon nanotubes 1224 .
[0026] According to an embodiment, a biosensor package structure 100 as illustrated in FIG. 4 comprises a base 180 with a surface, a cover box 110 , and a plurality of biosensors 120 . The base 180 and the cover box 110 are plastered to each other to define a cavity 1102 .
[0027] The base 180 which comprises conductive wires 150 can be a hard base or a flexible base. The hard base can be a ceramic base, a glass base, a quartziferous base, a siliceous base, an oxidative siliceous base, a diamond base, an alumina base, or any combination thereof. The flexible base can be a macromolecule base made by polydimethylsiloxane (PDMS), polycarbonate (PC), polymethyl methacrylate (PMMA), polyethylene (PE), polyimide (PI), polyethylene terephthalate (PET), polyether sulphone (PES), cellulose resin, polyvinylchloride (PVC), benzocyclobutene (BCB), acrylic resin, or any combination thereof. The base 180 comprises a siliceous slice 1802 with a surface and a silica layer 1804 formed on the surface of the siliceous slice 1802 . In one embodiment, a thickness of the siliceous slice 1802 is in a range from about 0.5 millimeter (mm) to about 2 mm, and a thickness of the silica layer 1804 is in a range from about 100 um to about 500 um.
[0028] The cover box 110 comprises an input passage 1104 and an output passage 1106 . The input passage 1104 is disposed in one side of the cover box 110 , and the output passage 1106 is disposed in an opposite side of the same. In the embodiment, the cover box 110 is a poly dimethyl siloxane (PDMS) box. Diameters of the input passage 1104 and the output passage 1106 is in a range from about 200 um to about 400 um. The cavity 1102 is defined as a cuboid, a length of the cavity 1102 is in a range from about 5 mm to about 10 mm, a width of the same is in a range from about 0.2 mm to about 1 mm, and a height of the same is in a range from about 50 um to about 100 um.
[0029] The biosensors 120 are located on the surface of the base 180 side by side. The first electrode 1210 and the second electrode 1220 of each of the biosensors 120 are connected to pins 160 by the conductive wires 150 . Thus, the biosensors 120 are electrically connected to the external circuit via the pins 160 .
[0030] Accordingly, when the measured object is delivered to the cavity 1102 by the input passage 1104 , and withdrawn from the cavity 1102 by the output passage 1106 , the measured object will pass through the biosensors 120 . Thus, the biosensors 120 react to the measured object such that current of each of the biosensors 120 is varied. Afterward, the current variation of each of the biosensors 120 is transmitted to the external circuit by the conductive wires 150 and the pins 160 . Finally, the external circuit can get information from the measured object.
[0031] According to an embodiment, a method for fabricating a plurality of biosensors is illustrated in following steps. For exemplary purpose, the embodiment is adapted for fabricating the biosensors 120 of FIG. 1 .
[0032] Referring to FIG. 5 , in step one, a base 180 with a surface is provided, and a carbon nanotube array 190 is formed on the surface of the base 180 . The carbon nanotube array 190 comprises a plurality of carbon nanotubes substantially parallel to each other.
[0033] Referring to FIG. 6 , in step two, a plurality of first leads 1212 and a plurality of second leads 1222 are formed by printing or plating conductive thick liquid on the surface of the base 180 . Each of the first leads 1212 corresponds to each of the second leads 1222 , and are electrically connected to each other by at least one of the carbon nanotubes of the carbon nanotube array 190 .
[0034] Referring to FIG. 7 , in step three, a part of the carbon nanotubes of the carbon nanotube array 190 is eliminated. Thus, the carbon nanotubes between each of the first leads 1212 and each of the second leads 1222 remain on the surface of the base 180 .
[0035] Referring to FIG. 8 , in step four, the carbon nanotubes between each of the first leads 1212 and each of the second leads 1222 are cut to form a plurality of first carbon nanotubes 1214 and a plurality of second carbon nanotubes 1224 . Each of the first carbon nanotubes 1214 corresponds to each of the second carbon nanotubes 1224 .
[0036] Referring to FIG. 9 , in step five, receptors 1230 are fabricated between each of the first leads 1212 and each of the second leads 1222 . Thus, the first carbon nanotubes 1214 and the second carbon nanotubes 1224 between each of the first leads 1212 and each of the second leads 1222 are electrically connected to each other by one of the receptors 1230 .
[0037] Accordingly, the present disclosure is capable of transmitting current variation of a biosensor via electrodes with carbon nanotubes. In addition, a width each of the electrodes can be decreased without influencing the accuracy and sensitivity of the biosensor. Thus, the biosensor can be easily manufactured with greater accuracy, sensitivity, and a longer lifetime.
[0038] It is to be understood that the above-described embodiments are intended to illustrate rather than limit the disclosure. Any elements described in accordance with any embodiments is understood that they can be used in addition or substituted in other embodiments. Embodiments can also be used together. Variations may be made to the embodiments without departing from the spirit of the disclosure. The above-described embodiments illustrate the scope of the disclosure but do not restrict the scope of the disclosure. | A method for fabricating a plurality of biosensors includes the steps of: providing a base with a surface; forming a carbon nanotube array including a plurality of carbon nanotubes substantially parallels to each other on the surface; forming a plurality of lead pairs on the surface, the plurality of lead pairs divides the plurality of carbon nanotubes into a plurality of first carbon nanotubes and a plurality of second carbon nanotubes; eliminating the plurality of second carbon nanotubes; cutting the plurality of first carbon nanotubes to form a plurality of third carbon nanotubes and a plurality of fourth carbon nanotubes; and fabricating a plurality of receptors to electrically connect the plurality of third carbon nanotubes to the plurality of fourth carbon nanotubes. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 13/635,125, filed on Sep. 14, 2012, which is National Stage application of International Application No. PCT/JP2011/001495, filed on Mar. 15, 2011, the disclosure of which is incorporated herein by reference in its entirety. International Application No. PCT/JP2011/001495 is entitled to and claims the benefit of Japanese Patent Application No. 2010-064676, filed on Mar. 19, 2010, the disclosures of which are incorporated herein by reference in their entirety.
TECHNICAL FIELD
[0002] The present invention relates to a biosensor kit which has a biosensor chip.
BACKGROUND ART
[0003] Biosensors which use a field-effect transistor (FET) have been proposed (see Patent Literatures 1 to 3). Generally, field-effect transistor-based biosensors include a field-effect transistor and a reaction field for a detection target, which is formed over a channel. The reaction field is provided with a reaction film with which the detection target is bound. The biosensor applies a gate voltage to the field-effect transistor by a gate electrode from above the reaction film, and measures a source-drain current at this time to determine the presence or absence, concentration etc. of the detection target, which has been provided on the reaction field. The FET-based biosensors exhibit very high sensitivity, and therefore there has been growing expectations for practical use.
CITATION LIST
Patent Literature
[0000]
PTL 1 Japanese Patent Application Laid-Open No. 2004-85392
PTL 2 Japanese Patent Application Laid-Open No. 2006-201178
PTL 3 Japanese Patent Application Laid-Open No. 2007-139762
SUMMARY OF INVENTION
Technical Problem
[0007] Despite such growing expectations for use as high-sensitivity sensors, the FET-based biosensors suffer from the drawback of a large variation in sensitivity depending on the service condition. Sensitivity variation occurs depending not only on the environment in which measurement is done by the biosensor, but also on the storage condition for the biosensor.
[0008] For instance, when the biosensor in storage is exposed to humidity, a channel (especially carbon nanotube channel) of the field-effect transistor may degrade, and hysteresis or the like may occur. When the biosensor in storage is exposed to light, the light infiltrates into the semiconductor substrate of the FET and the characteristics may be changed. Alternatively, when target recognition molecules are immobilized on a reaction field, the molecules may degrade during storage of the biosensor to cause sensitivity reduction.
[0009] An object of the present invention is therefore to provide means of preventing deterioration of a FET-based biosensor during storage or transportation. Thereby, commercialization of FET-based biosensors is achieved.
Solution to Problem
[0010] A first aspect of the present invention relates to a biosensor kit given below.
[0011] [1] A biosensor kit including:
[0012] a biosensor chip for measuring a value of an electric current in a field-effect transistor, the electric current generated when a detection target is allowed to react with a target recognition molecule immobilized onto a reaction field connected to the field-effect transistor; and
[0013] a packing body which seals therein the biosensor chip, the packaging body being formed from a packing material having a metal film, wherein
[0014] the biosensor chip has the field-effect transistor and a mounting board having thereon the field-effect transistor,
[0015] the field-effect transistor comprises: a semiconductor substrate having an insulating film on a surface thereof; a source electrode and a drain electrode, the source electrode and the drain electrode being arranged on the insulating film; a channel formed of a semiconductor, the channel being arranged on the insulating film and being electrically connected to the source electrode and the drain electrode; and the reaction field formed on the semiconductor substrate, the reaction field for supplying a gate potential to the field-effect transistor, and
[0016] the mounting board includes thereon external connection terminals electrically connected to the source electrode, the drain electrode and the reaction field, respectively.
[0017] [2] The biosensor kit according to [1], wherein the biosensor kit further comprises the target recognition molecule enclosed in the packing body, wherein the target recognition molecule is packed separately from the biosensor chip.
[0018] [3] The biosensor kit according to [2], wherein the reaction field has been subjected to surface treatment for immobilizing the target recognition molecule onto the reaction field.
[0019] [4] The biosensor kit according to [3], wherein the surface treatment for the reaction field is silanizing treatment.
[0020] [5] The biosensor kit according to [3], wherein the surface treatment for the reaction field is a treatment in which a thin film of gold or platinum is formed on the reaction field and an SAM film is formed on the thin film.
[0021] [6] The biosensor kit according to [1], wherein the target recognition molecule is immobilized on the reaction field.
[0022] [7] The biosensor kit according to [6], wherein the reaction field is moisturized by a moisturizing member.
[0023] [8] The biosensor kit according to any one of [1] to [7], further including a desiccating agent or a moisture absorbent enclosed in the packing body.
[0024] [9] The biosensor kit according to any one of [1] to [8], wherein the channel is formed from a carbon nanotube, polysilicon or amorphous silicon.
[0025] [10] The biosensor kit according to any one of [1] to [9], wherein the insulating film is a silicon nitride film, a silicon oxide film or a hafnium oxide film.
[0026] A second aspect of the present invention relates to a biosensor kit given below.
[0027] [11] A biosensor kit including:
[0028] a biosensor chip for measuring a value of an electric current in a field-effect transistor, the electric current generated when a detection target is allowed to react with a target recognition molecule immobilized onto a reaction field and the reaction field is connected to the field-effect transistor; and
[0029] a packing body which seals therein the biosensor chip, the packaging body being formed from a packing material having a metal film, wherein
[0030] the biosensor chip has a mounting board and the reaction field formed on the mounting board,
[0031] the mounting board includes an external connection terminal for applying a predetermined potential to the reaction field, and an external connection terminal for supplying a potential generated in the reaction field as a gate potential of the field-effect transistor.
[0032] [12] The biosensor kit according to [11], further including the target recognition molecule enclosed in the packing body, wherein the target recognition molecule is packed separately from the biosensor chip.
[0033] [13] The biosensor kit according to [11] or [12], wherein the reaction field has been subjected to surface treatment for immobilizing the target recognition molecule onto the reaction field.
[0034] [14] The biosensor kit according to [13], wherein the surface treatment for the reaction field is silanizing treatment.
[0035] [15] The biosensor kit according to [13], wherein the surface treatment for the reaction field is a treatment in which a thin film of gold or platinum is formed on the reaction field and an SAM film is formed on the thin film.
[0036] [16] The biosensor kit according to [11], wherein the target recognition molecule is immobilized on the reaction field.
[0037] [17] The biosensor kit according to [16], wherein the reaction field is moisturized by a moisturizing member.
[0038] [18] The biosensor kit according to any one of [11] to [17], wherein the reaction field is formed on a semiconductor substrate arranged on the mounting board.
[0039] [19] The biosensor kit according to any one of [11] to [17], wherein the mounting board is made from an inorganic material, an organic material or a mixed material thereof.
Advantageous Effects of Invention
[0040] According to the biosensor kit of the present invention, the characteristics of the field-effect transistor provided in the biosensor chip are hard to change during storage or transportation of the biosensor kit, and accordingly stable biosensing can be achieved.
BRIEF DESCRIPTION OF DRAWINGS
[0041] FIG. 1A is a plan view of a first example of a biosensor chip of a first form;
[0042] FIG. 1B is a sectional view of the biosensor chip taken along line A-A′ illustrated in FIG. 1A ;
[0043] FIG. 2A is a plan view of a second example of the biosensor chip of the first form;
[0044] FIG. 2B is a sectional view of the biosensor chip taken along line A-A′ illustrated in FIG. 2A ;
[0045] FIG. 3A is a plan view of a third example of the biosensor chip of the first form;
[0046] FIG. 3B is a sectional view of the biosensor chip taken along line A-A′ illustrated in FIG. 3A ;
[0047] FIG. 4A is a plan view of a biosensor kit including the biosensor chip illustrated in FIG. 1 ;
[0048] FIG. 4B is a plan view of a biosensor kit including the biosensor chip illustrated in FIG. 1 ;
[0049] FIG. 5 is a plan view of a biosensor kit including the biosensor chip illustrated in FIG. 2 ;
[0050] FIG. 6 is a sectional view of a biosensor kit including the biosensor chip illustrated in FIG. 3 ;
[0051] FIG. 7 is a plan view of a detection system having the biosensor chip illustrated in FIG. 2 ;
[0052] FIG. 8A is a plan view of an example of a biosensor chip of a second form;
[0053] FIG. 8B is a plan view of another example of the biosensor chip of the second form;
[0054] FIG. 9A is a plan view of a biosensor kit including a biosensor chip illustrated in FIG. 8A ;
[0055] FIG. 9B is a plan view of a biosensor kit including the biosensor chip illustrated in FIG. 8A ; and
[0056] FIG. 10 is a plan view of a detection system having the biosensor chip illustrated in FIG. 9B .
DESCRIPTION OF EMBODIMENTS
[0057] Biosensor Kit
[0058] A biosensor kit of the present invention has a biosensor chip and a packing body which seals therein the biosensor chip. The packing body for sealing therein the biosensor chip is preferably a laminated film having a metal film. This is to effectively prevent the possible permeation of moisture and penetration of light from the outside to the inside. The packing body has, for instance, a heat-fusible resin layer as the inner layer of a film constituting the packing body, and the opening of the packing body is closed by fusion.
[0059] In the packing body, a desiccating agent or a moisture absorbent may be sealed together with the biosensor chip. This is because if the biosensor chip has been exposed to moisture, the chip tends to easily deteriorate. In addition, elements to be used in the sensing step may also be enclosed in the packing body, e.g, a washer for washing a reaction field, and a remover for removing a washing liquid from the reaction field after washing.
[0060] The biosensor chip included in the biosensor kit of the present invention is classified into two forms depending on whether the biosensor chip includes a field-effect transistor element. The biosensor chip of the first form has a field-effect transistor and a mounting board on which the field-effect transistor is mounted. On the other hand, the biosensor chip of the second form has the mounting board and the reaction field formed on the mounting board, but does not have a field-effect transistor structure.
[0061] Detection System for Detection Target
[0062] A detection system for the detection target of the present invention includes a biosensor chip and a detection device. The biosensor chip may be biosensor chip of either of the first and second forms. The detection system for the detection target, which is provided with the biosensor chip of the second form, free from a field-effect transistor, employs a detection device including the field-effect transistor. The detection device may also include elements to be used in the sensing step, e.g., a washer for washing a reaction field, and a remover for removing a washing liquid from the reaction field after washing.
[0063] The biosensor chip of the first form and the biosensor chip of the second form will be each described below.
[0064] Biosensor Chip of First Form
[0065] The biosensor chip of the first form has a field-effect transistor and a mounting board. The field-effect transistor has a semiconductor substrate having an insulating film thereon, a source electrode and a drain electrode which are arranged on the insulating film, and a channel formed of a semiconductor which is arranged on the a insulating film and is electrically connected to the source electrode and the drain electrode.
[0066] The semiconductor substrate of the field-effect transistor is usually a silicon substrate, but is not necessarily limited thereto, and may be an SOI substrate, a compound semiconductor substrate or a glass substrate. The source/drain electrodes and the channel are arranged on the surface of the semiconductor substrate, with the insulating film being formed on the surface on which the components are arranged. The insulating film is not limited in particular, and is appropriately selected according, for example, to the type of the channel; it can be a silicon oxide film, a silicon nitride film or a hafnium oxide film.
[0067] The material of the source electrode and the drain electrode may be a conductive material such as a metal or semiconductor material, and is not limited in particular. The channel which connects the source electrode and the drain electrode may be made of semiconductor, and can be a carbon nanotube, a polysilicon film or an amorphous silicon film. When the channel is formed from a carbon nanotube, the insulating film on the surface of the semiconductor substrate may be preferably a silicon nitride film or a hafnium oxide film. On the other hand, when the channel is formed from polysilicon or amorphous silicon, the insulating film on the surface of the semiconductor substrate may be preferably a silicon oxide film or a hafnium oxide film.
[0068] It is preferable that the source electrode, the drain electrode and the channel are sealed so as not to come in contact with moisture or not to be exposed with light. When moisture comes in contact with the channel or the channel is exposed with light, the characteristics of the field-effect transistor may remarkably change, which may result in failure to conduct proper detection. In particular, when the channel is formed from polysilicon or amorphous silicon, the channel tends to be easily affected by light. The sealing may be accomplished by covering the source electrode, the drain electrode and the channel with an inorganic material or organic material having low permeability for moisture and light. In addition, when the channel is formed from a carbon nanotube, the characteristics of the channel are greatly affected particularly by moisture. For this reason, a passivation film such as a silicon nitride film or hafnium oxide film may be formed at least on the channel, and the film may be covered with inorganic or organic material.
[0069] Furthermore, the field-effect transistor has a reaction field that functions as a gate electrode, on the semiconductor substrate. The reaction field may be positioned on the surface where the source electrode, the drain electrode and the channel are arranged, or may also be positioned on the surface of the semiconductor substrate remote from the source electrode, the drain electrode and the channel. It is preferable that the insulating film is provided also on the surface of the reaction field.
[0070] It is necessary to apply a desired potential (scanning potential or reference potential) to the reaction field which has been formed on the semiconductor substrate. For this reason, a gate electrode is preferably arranged around a part or all of the perimeter of the reaction field. The material of the gate electrode is not limited in particular, and may be a metal such as gold, platinum, titanium or aluminum, conductive plastic or the like.
[0071] The reaction field has target recognition molecules immobilized on its surface or is configured to be capable of immobilizing the recognition molecules on its surface. Examples of the target recognition molecules include proteins such as antibodies, enzymes and lectin; nucleic acids; and oligosaccharides or polysaccharides; or substances having any of the structures thereof. A molecule which specifically reacts with a detection target is appropriately selected. The detection target is, for example, a protein or chemical substance of particular type.
[0072] When the target recognition molecules are immobilized on the surface of the reaction field, the reaction field may be preferably moisturized so as to avoid degradation of the immobilized molecules. This is because the target recognition molecules generally tend to degrade due to dryness. In order to moisturize the reaction field, a moisturizing seal may be arranged so as to cover the reaction field. The moisturizing seal refers to a film member which is hard to allow moisture to pass through it and which is applied so as to cover the reaction field with a peelable adhesive. The film which is hard to allow moisture to pass through it is, for instance, a multilayer film having a metal layer.
[0073] On the other hand, when the reaction field is so configured as to be capable of immobilizing target recognition molecules on its surface as needed rather than having them immobilized on its surface, it is preferable that the target recognition molecules are sealed together with the biosensor chip in the packing body. The target recognition molecules which are sealed in the packing body are sealed preferably by a separate packing material. This is because, as described above, it is preferable that the field-effect transistor does not come in contact with moisture, but on the other hand, it is often the case that the target recognition molecules are preferably kept in a moisturized environment.
[0074] In order for the target recognition molecules to be capable of being immobilized on the surface of the reaction field as needed, the surface of the reaction field may be subjected, for instance, to a silanizing treatment. The silanizing treatment includes surface treatment by a silane coupling agent or other agent. The reaction field may have a self-assembly monolayer (SAM) film formed on its surface. In order to form the SAM film, firstly, a metal thin film (e.g., gold or platinum thin film) may be formed on the surface of the reaction field, followed by arrangement of the SAM film on the metal thin film.
[0075] The biosensor chip of the first form has a mounting board on which a field-effect transistor is mounted. It is preferable that the mounting board is made of an insulating material and does not have optical transparency. This is because when light which has passed through the mounting board strikes the channel or semiconductor substrate of the field-effect transistor, their characteristics change. The mounting board may be, for instance, a molded article of an organic resin containing a pigment.
[0076] The mounting board has terminals which are electrically connected to the source electrode, the drain electrode and the gate electrode of the field-effect transistor, respectively. The biosensor chip of the first form is attached to a detection device (later described) through these terminals.
[0077] The biosensor chip of the first form can be manufactured according, for instance, to the following process.
[0078] 1) An insulating film such as a silicon oxide film, a silicon nitride film or a hafnium oxide film is formed on the surface of a semiconductor substrate. The insulating film may be formed by, for example, thermal oxidation method or CVD.
[0079] 2) A source electrode, a drain electrode and a channel which connects the electrodes are formed on the insulating film. In the case of a carbon nanotube channel, the channel is formed by CVD using an organic material such as ethyl alcohol, or using a ready-made carbon nanotube. In the case of polysilicon channel or amorphous silicon channel, the channel can be formed by CVD, epitaxial growth or other method. After channel formation, a passivation film formed of an insulating film such as a silicon oxide film, a silicon nitride film and or hafnium oxide film is formed at least on the channel, and both ends of the channel are opened. After that, a conductive material is deposited by sputtering or other method on the insulating film so as to be connected with the ends of the channel, and unnecessary portions are removed by etching to form the source electrode and the drain electrode.
[0080] 3) A reaction field is formed on the semiconductor substrate. In the case of the first form, the reaction field is formed on the surface where the source electrode, the drain electrode and the channel are formed, in a desired region on the insulating film which has been formed in the above step (1). The reaction field is subjected to surface treatment such that target recognition molecules can be immobilized on the reaction field. The surface treatment differs between in-liquid measurement and in-air measurement. When the biosensor is used for in-liquid measurement, a metal film such as a gold or platinum film, which is chemically stable, is formed b vacuum deposition, sputtering or other method in order to limit the generation of ions from the liquid sample. After that, an SAM film is formed so as to facilitate the immobilization of target recognition molecules. When the biosensor is used for in-air measurement, the surface is treated with a silane coupling agent or other agent. Furthermore, a scanning electrode or a reference electrode is arranged around the perimeter or in the vicinity of the reaction field so that a desired potential can be applied to the reaction field. This scanning electrode or reference electrode is formed, for example, simultaneously with the source electrode and the drain electrode in the step 2).
[0081] 4) The semiconductor substrate including the field-effect transistor is mounted on the mounting board to form the biosensor chip. The mounting board has three external connection terminals formed thereon. The respective terminals of the mounting board are connected to the source electrode, the drain electrode and the gate electrode of the field-effect transistor by, for example, wire bonding or bump connection method.
[0082] 5) The source electrode, the drain electrode, the channel and the connections of the terminals are sealed by an inorganic material or an organic material having low permeability for moisture and light by, for example, potting method or transfer molding. In order to prevent the peeling of the sealing material, the biosensor chip may be subjected to plasma cleaning treatment before the sealing treatment. However, when the carbon nanotube is used in the field-effect transistor, there is a high possibility that the carbon nanotube is destroyed by plasma, and accordingly a shield layer formed of a metal is provided on the carbon nanotube, for instance. Thereby, the destruction due to the plasma can be prevented.
[0083] The biosensor kit is obtained by sealing the biosensor chip thus obtained in the above described step 5), in a packing body provided with a desiccating agent or a moisture absorbent. When the target recognition molecules are immobilized on the biosensor chip beforehand, the reaction field is covered with a moisturizing seal. In addition, when the target recognition molecules are not immobilized on the biosensor chip beforehand, the target recognition molecules, which have been separately packed, are enclosed in the packing body. It should be noted that the packing body may be filled with an inert gas.
[0084] FIG. 1 illustrates a first example of a biosensor chip of a first form. FIG. 1A is a plan view of biosensor chip 10 , and FIG. 1B is a sectional view of biosensor chip 10 taken along line A-A′ of FIG. 1A . Biosensor chip 10 illustrated in FIG. 1 has mounting board 11 ; and components constituting a field-effect transistor: semiconductor substrate 20 , source electrode 21 , drain electrode 22 , channel 23 , reaction field 24 , and scanning electrode or reference electrode 25 . Furthermore, three external connection terminals 30 ( 30 A, 30 B, 30 C) are arranged at one end of the mounting board 11 , and are electrically connected to source electrode 21 , drain electrode 22 , and scanning electrode or reference electrode 25 , respectively.
[0085] It is preferable to seal source electrode 21 , drain electrode 22 and channel 23 of the biosensor chip 10 with sealing member 40 , to shield light. Sealing member 40 may be a member which does not allow light to pass through it, and may be made of organic resin or inorganic material. It should be noted that at least channel 23 of biosensor chip 10 is covered with a passivation film (not shown).
[0086] FIG. 2 illustrates a second example of the biosensor chip of the first form. FIG. 2A is a plan view of biosensor chip 10 ′, and FIG. 1B is a sectional view of biosensor chip 10 ′ taken along line A-A′ of FIG. 2A . Biosensor chip 10 ′ illustrated in FIG. 2 includes components similar to those of biosensor chip 10 illustrated in FIG. 1 , and furthermore, target recognition molecules 26 are immobilized on reaction field 24 . Moreover, reaction field 24 of biosensor chip 10 ′ is covered and moisturized with moisturizing seal 50 .
[0087] FIG. 3 illustrates a third example of the biosensor chip of the first form. FIG. 3A is a plan view of biosensor chip 10 ″, and FIG. 3B is a sectional view of biosensor chip 10 ″ taken along line A-A′ of FIG. 3A . Biosensor chip 10 ″ includes components similar to those of biosensor chip 10 ′ illustrated in FIG. 2 , but reaction field 24 is provided on the back surface of the semiconductor substrate 20 (i.e., surface remote from the surface on which source electrode 21 , drain electrode 22 and channel 23 are arranged). Reaction field 24 of biosensor chip 10 ″ has target recognition molecules 26 immobilized thereon, and has moisturizing seal 50 arranged thereon. It should be noted that as with biosensor chip 10 , reaction field 24 may not have target recognition molecules 26 immobilized thereon, and may not have moisturizing seal 50 arranged thereon.
[0088] FIG. 4A illustrates a biosensor kit which has biosensor chip 10 (see FIG. 1 ) sealed in chip packing body 100 . The moisture absorbent or desiccating agent 110 is also sealed in chip packing body 100 together with biosensor chip 10 . FIG. 4B illustrates a biosensor kit which has biosensor chip 10 and target recognition molecules 26 sealed in kit packing body 200 . The biosensor chip is sealed in packing body 100 , as illustrated in FIG. 4A . Target recognition molecules 26 are sealed also in separate packing body 300 .
[0089] FIG. 5 illustrates a biosensor kit which has biosensor chip 10 ′ ( FIG. 2 ) sealed in chip packing body 100 . The moisture absorbent or desiccating agent 110 is sealed in chip packing body 100 together with biosensor chip 10 ′.
[0090] FIG. 6 illustrates a biosensor kit which has biosensor chip 10 ″ ( FIG. 3 ) sealed in chip packing body 100 . The moisture absorbent or desiccating agent 110 is sealed in chip packing body 100 together with biosensor chip 10 ″.
[0091] FIG. 7 illustrates a detection system which includes the biosensor chip of the first form (biosensor chip 10 ′ (see FIG. 2 ) as an example), and detection device 400 . Detection device 400 includes detection circuit 440 which includes: three input terminals 410 ( 410 A to 410 C); electric current detection unit 420 connected to input terminal 410 A; power source 470 connected to electric current detection unit 420 ; a ground connected to input terminal 410 B; and power source 430 connected to input terminal 410 C. Detection device 400 further includes: determination unit 450 for determining a detection result on the basis of the detected electric current; display unit 460 for displaying the result; and storage unit for recording the result (not shown). Determination unit 450 includes a processor, a ROM, a RAM and the like which are necessary for performing calculation on the basis of the detected electric current value, and determining the presence or absence of and the concentration of the detection target. A liquid crystal display, an organic EL display, a plasma display or the like is used as display unit 460 . A lamp indicator with an LED may be used as a simple display unit. The storage unit includes a rewritable nonvolatile memory, for instance, a flash memory.
[0092] Biosensor chip 10 ′ is attached to detection device 400 , whereby input terminals 410 A to 410 C of the detection device are connected to external connection terminals 30 A to 30 C of biosensor chip 10 ′, respectively. With this configuration, power source 430 can apply a desired potential to scanning electrode or reference electrode 25 , and electric current detection unit 420 can detect the electric current flowing through channel 23 .
[0093] Determination unit 450 stores therein, for instance, a relationship between the electric current to be detected and the amount of the detection target (e.g., working curve).
[0094] Biosensor Chip of Second Form
[0095] The biosensor chip of the second form has a mounting board, and a reaction field formed on the mounting board. A semiconductor substrate may be arranged on the mounting board, and the reaction field is preferably formed on the semiconductor substrate. A desired potential needs to be applied to the reaction field of the biosensor chip of the second form. For this reason, a reference electrode is arranged around a part or all of the perimeter of the reaction field.
[0096] As in the case of the biosensor chip of the first form, the reaction field has target recognition molecules immobilized on its surface, or is configured to be capable of immobilizing the recognition molecules on the surface. The reaction field may also be moisturized by a moisturizing seal or the like.
[0097] The mounting board is similar to the mounting board of the first form. An external connection terminal for applying a potential to the reference electrode of the reaction field, and an external connection terminal for taking out the potential generated in the reaction field are arranged on the mounting board. The biosensor chip of the second form is attached to a detection device (later described) through these terminals.
[0098] The biosensor chip of the second form can be manufactured, for instance, according to the following process. 1) An insulating film such as a silicon oxide film, a silicon nitride film or a hafnium oxide film is formed on the surface of a semiconductor substrate. The insulating film may be formed by thermal oxidation, CVD method or other method. 2) A reaction field is formed in a desired region of the semiconductor substrate having the insulating film formed thereon in the above step 1). Next, a part of the insulating film is opened in which an electrode for drawing the potential of the reaction field is to be formed. Next, a conductive film made of aluminum or other metal is formed on the insulating film around the perimeter or in the vicinity of this reaction field. Then, a gate electrode or a reference electrode; an interconnection drawn from the electrode; a connection terminal for being connected to an interconnection on the mounting board (later described); and an electrode for drawing the potential of the reaction field are formed by etching. The reaction field formed in this way is subjected to surface treatment such that target recognition molecules can be immobilized thereon, similarly to that of the first form. Furthermore, the target recognition molecules may be immobilized on the reaction field.
[0099] 3) The semiconductor substrate having the reaction field thereon is mounted on the mounting board to form the biosensor chip. The mounting board has two external connection terminals formed thereon. One of the external connection terminals is connected to a terminal to be connected to the gate electrode of an external field-effect transistor, and the other is connected to a terminal of the scanning electrode or reference electrode, by wire bonding or bump connection method, for instance. The connecting portions of the external connection terminals are sealed by an inorganic material or an organic material having low permeability for moisture, by potting method or transfer molding, for instance.
[0100] The biosensor kit is obtained by sealing the obtained biosensor chip in the packing body.
[0101] It should be noted that a substrate to be used in the biosensor chip of the present form is not limited to the semiconductor substrate, but can be an insulating substrate. When a glass substrate is used, for instance, the biosensor chip can be prepared without separately preparing the mounting board. Firstly, a conductive film made of aluminum or other metal is formed on the glass substrate, and a reaction field, an interconnection drawn from the reaction field, and an external connection terminal are formed by etching. Next, an insulating film such as a silicon oxide film, a silicon nitride film or a hafnium oxide film is formed by CVD so as to cover the reaction field. Next, the conductive film made of aluminum or other metal is formed on the insulating film around the perimeter or in vicinity of the reaction field, and a scanning electrode or reference electrode, an interconnection drawn from the electrode and an external connection terminal are formed by etching. The biosensor kit is obtained by subjecting the reaction field obtained in this way to a surface treatment similar to that described above, and sealing the reaction field in the packing body.
[0102] FIG. 8A illustrates an example of a biosensor chip of a second form. Biosensor chip 60 has mounting board 61 , and semiconductor substrate 70 arranged on mounting board 61 . Semiconductor substrate 70 has reference electrode 71 and reaction field 72 arranged thereon. Mounting board 61 has two external connection terminals 80 (external connection terminal 80 A for applying gate potential, and external connection terminal 80 B for applying reference potential) arranged thereon. A connector portion may be sealed by arranging sealing member 90 thereon.
[0103] FIG. 8B illustrates another example of the biosensor chip of the second form which includes a glass substrate. Biosensor chip 60 - 1 has glass substrate 65 ; reaction field 72 and interconnection 75 for drawing a potential in the reaction field, which are formed on the glass substrate; insulating film 66 formed thereon; and reference electrode 71 and an interconnection for applying a reference potential, which are formed on the insulating film. Glass substrate 65 further has two external connection terminals (external connection terminal 80 A for drawing gate potential, and external connection terminal 80 B for applying reference potential) arranged thereon.
[0104] FIG. 9A illustrates a biosensor kit including kit packing body 200 that encloses therein biosensor chip 60 sealed in chip packing body 100 , and target recognition molecules 73 which are sealed in packing body 300 . Moisture absorbent 110 is also sealed together with biosensor chip 60 in chip packing body 100 .
[0105] FIG. 9B illustrates a biosensor kit that has biosensor chip 60 ′ in which target recognition molecules 73 are immobilized on the reaction field 72 of biosensor chip 60 illustrated in FIG. 8 and the reaction field is covered with moisturizing seal (not shown), sealed in chip packing body 100 . Moisture absorbent 110 is also sealed in chip packing body 100 together with biosensor chip 60 ′.
[0106] FIG. 10 illustrates a detection system for a detection target, which has biosensor chip 60 ′ (see FIG. 9B ) of the second form attached to detection device 500 . Detection device 500 has detection circuit 550 which includes: two input terminals 510 ( 510 A, 510 B); field-effect transistor 540 ; electric current detection unit 520 ; power source 580 ; and power source 530 . Input terminal 510 A is connected to the gate of field-effect transistor 540 . Input terminal 510 B is connected to power source 530 . Detection device 500 further includes: determination unit 560 for determining a detection result on the basis of the detected electric current; display unit 570 for displaying the result; and a storage unit for recording the result (not shown). Determination unit 560 includes a processor, a ROM, a RAM and the like which are necessary for performing calculation on the basis of the detected electric current value, and determining the presence or absence of and the concentration of the substance to be detected. A liquid crystal display, an organic EL display, a plasma display or the like is used as display unit 570 . A lamp indicator with an LED may be used as a simple display unit. The storage unit includes a rewritable nonvolatile memory, for instance, a flash memory. Field-effect transistor 540 includes: a channel which is formed, for instance, from a carbon nanotube, polysilicon and amorphous silicon; a source electrode; and a drain electrode. These components are sealed by an inorganic material or an organic material having low permeability for moisture and light. With this configuration in which field-effect transistor 540 is provided in detection device 500 , it is only necessary to prepare high-sensitivity field-effect transistors in a number equal to that of detection devices. Thereby, the influence of yield can be mitigated. In addition, the biosensor chip itself can be inexpensively manufactured.
[0107] Biosensor chip 60 ′ is attached to detection device 500 , and input terminals 510 A and 510 B of the detection device are connected to external connection terminals 80 A and 80 B of biosensor chip 60 ′, respectively. Thereby, the potential generated in reaction field 72 can be used as a gate potential of field-effect transistor 540 , and power source 530 can apply a desired reference potential to reference electrode 71 .
[0108] Determination unit 570 stores therein, for instance, a relationship between the electric current to be detected and the amount of the detection target (e.g., working curve).
[0109] Method for Detecting Detection Target
[0110] A detection target can be detected using the biosensor kit of the present invention according to the following procedure, for example.
[0111] Firstly, the biosensor chip is taken out from the packing body of the biosensor kit of the present invention. When the taken out reaction field of the biosensor chip does not have any target recognition molecules immobilized thereon, the target recognition molecules are immobilized.
[0112] Next, a sample containing the detection target is added to the reaction field. The sample is usually an aqueous solution. After the sample has been added to the reaction field, the sample is incubated. Then, the reaction field is washed. The reaction field may be washed, for instance, with water. After the reaction field has been washed, the washing liquid (water) in the reaction field is preferably removed as much as possible. The washing liquid can be removed, for instance, by drying the reaction field under reduced pressure, or drying the reaction field by blowing a gas to the reaction field.
[0113] After that, the biosensor chip is attached to the above detection device. After attachment, an electric current flowing through the channel of the field-effect transistor (which may be provided in biosensor chip or detection device) is measured. The presence or absence of and the concentration of the detection target in the sample are detected on the basis of the measurement result.
[0114] The present application claims the priority of Japanese Patent Application No. 2010-064676 filed on Mar. 19 in 2010, the contents of which including the specification and drawings are incorporated herein by reference in its entirety.
INDUSTRIAL APPLICABILITY
[0115] The present invention can achieve practical high-sensitivity biosensing by avoiding the degradation of a FET-based biosensor during the storage of transportation of the bio sensor.
REFERENCE SIGNS LIST
[0000]
10 , 10 ′ and 10 ″ Biosensor chip
11 Mounting board
20 Semiconductor substrate
21 Source electrode
22 Drain electrode
23 Channel
24 Reaction field
25 Scanning electrode or reference electrode
26 Target recognition molecules
30 A, 30 B and 30 C External connection terminal
40 Sealing member
50 Moisturizing seal
60 , 60 ′ and 60 - 1 Biosensor chip
61 Mounting board
65 Glass substrate
66 Insulating film
70 Semiconductor substrate
71 Reference electrode
72 Reaction field
73 Target recognition molecules
75 Interconnection for drawing potential of reaction field
80 A and 80 B External connection terminal
90 Sealing member
91 Moisturizing seal
100 Chip packing body
110 Moisture absorbent or desiccating agent
200 Kit packing body
300 Packing body
400 Detection device
410 A, 410 B and 410 C Input terminal
420 Electric current detection unit
430 Power source
440 Detection circuit
450 Determination unit
460 Display unit
470 Power source
500 Detection device
510 A and 510 B Input terminal
520 Electric current detection unit
530 Power source
540 Field-effect transistor
550 Detection circuit
560 Determination unit
570 Display unit
580 Power source | Disclosed are: a biosensor kit in which a biosensor utilizing a field effect transistor is not deteriorated during storage or transport; and a system for detecting a substance of interest, which is equipped with the biosensor chip. The biosensor kit comprises a biosensor chip which can measure a substance of interest quantitatively and a package which can hermetically seal the biosensor chip and is composed of a packaging material comprising a metal film. The biosensor chip can measure the substance quantitatively based on the value of a current generated in a field effect transistor when the substance is reacted with a molecule that can recognize the substance and is immobilized on a reaction field connected to the field effect transistor. The biosensor chip comprises the field effect transistor and a mounting substrate on which the field effect transistor is mounted. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is related to automative repair equipment and techniques and, more particularly, is directed towards a novel method and apparatus for correcting front end alignment which results from bent front axle assemblies.
2. Description of the Prior Art
The importance of maintaining proper front end alignment in motor vehicles is well recognized. The multitude of parts which make up the wheel support sections of a motor vehicle each provide a potential source of misalignment. While conventional alignment equipment available to most mechanics is able to correct many such sources of misalignment, many situations nevertheless arise for which conventional equipment simply will not do the job.
Misalignment caused by deformed or bent struts is an example of a condition for which conventional alignment equipment is unsatisfactory. Described in my prior U.S. Patent Application Ser. No. 715,375, filed Aug. 18, 1976, and now U.S. Pat. No. 4,103,531 is a method and apparatus for correcting bent strut misalignment which provides an economic and effective solution to the problem of conveniently and accurately correcting misalignment resulting from bent or otherwise deformed struts.
I have recognized that a similar problem exists with respect to misalignment caused by bent front axle assemblies, such as those found in Volkswagen automobiles. These front axle assemblies are characterized by a twin I beam horizontally disposed front axle which has a pair of upper and lower torsion arms extending rearwardly from both ends thereof. The spindle, hub and drum of the vehicle are connected via the upper and lower ball joints to the upper and lower torsion arms, respectively.
In earlier model Volkswagens, for example, which include model years 1948 through 1969, the twin axle beam is connected at its approximate mid-section to the head of the frame of the automobile, commonly referred to as the header. I have found that the twin beams tend to be deformed between the connection point to the header and the torsion arms if the vehicle is in an accident, runs over a curb, or the like. For later model Volkswagens (beginning with model year 1970), the twin I beam is mounted to the frame by twin, spaced headers which are arranged in a Y-configuration with respect to the front axle, rather than being centrally located as is the case with the earlier models. I have found, with the later models, that the torsion arms themselves, which extend laterally and rearwardly from both ends of the twin front axle, are apt to be bent if the automobile jumps a curb, is involved in an accident, runs over a pothole, or the like.
Prior art techniques of correcting misalignment resulting from either bent front axle beams or bent torsion bars required the front end of the automobile to be totally dismantled in order to remove the damaged part, and either bent it back into shape, or replace it.
It therefore may be appreciated that a technique which would enable the bent or deformed axle and/or torsion arms to be straightened while remaining installed on the automobile would provide a great advance over presently available techniques in terms of both labor and part economy. It is towards this end that the present invention is advanced.
OBJECTS AND SUMMARY OF THE INVENTION
it is therefore a primary object of the present invention to provide a method and apparatus for correcting misalignment of the front end of an automobile resulting from a bent axle assembly which overcomes all of the deficiencies noted above with respect to prior art techniques and devices.
Another object of the present invention is to provide a new and improved technique for correcting misalignment resulting from deformed front and axles which does not require the front end of the automobile to be dismantled, thereby permitting correct alignment to be achieved in far less time than previously possible.
An additional object of the present invention is to provide apparatus for permitting the front ends of Volkswagen automobiles to be easily, simply, cheaply and quickly aligned.
A still further object of the present invention is to provide a technique and device for permitting easy, accurate and rapid camber adjustment of the front end of certain automobiles when the misalignment is caused by a bent, deformed, or otherwise misaligned front axle assembly.
A more specific object of the present invention is to provide apparatus for correcting bent axle misalignment which is universally applicable to Volkswagen automobiles, and which effectuates straightening of their front twin I beam and/or upper and lower torsion arms without requiring the front end to be dismantled, and in a minimum amount of time.
The foregoing and other objects are attained in accordance with one aspect of the present invention through the provision of apparatus which comprises means for clamping an axle assembly of a vehicle, and means operatively coupled to the clamping means for bending the axle assembly while installed in the vehicle. The bending means more particularly comprises hydraulic jack means, and means for supporting the hydraulic jack means. The hydraulic jack supporting means preferably comprises a base member which is adapted to be positioned underneath the axle assembly, and a breast plate which is pivotally coupled to the base member. Means are further pivotally coupled to the base member which is adapted to support the lower end of the shock absorber of the vehicle.
In accordance with more specific aspects of the present invention, the base member comprises a substantially planar support plate that is positioned rearwardly of the axle assembly and which includes aperture means formed therein for pivotally receiving the breast plate. The breast plate provides a means for supporting the base of the hydraulic jack such that the latter is disposed substantially horizontally during use. The jack support means comprise a plurality of substantially vertically disposed plates which are arranged to support the base of the jack in a plurality of different bending positions. The outer, vertically oriented wall of the breast plate is curved in such a fashion so as to be congruent with the inner wheel housing against which the breast plate is positioned during use.
In accordance with yet more specific aspects of the present invention, for early model Volkswagens (1948-1969), the breast plate is provided in the form of left and right breast plate assemblies, which are substantial mirror images of one another, and which are adapted to be utilized respectively on the left and right front ends of Volkswagen automobiles (1948-1969). The rear end of each breast plate in use in pivotally attached to the rear of the support plate, while the front end of the breast plate is laterally movable.
In accordance with yet other more specific aspects of the present invention, the breast plate, for Volkswagens manufactured after 1970, may be comprised of a single, reversible breast plate assembly which may be adapted for use on both the left and right front ends of such Volkswagen automobiles. For the alternate breast plate assembly, the front end thereof is pivotally mounted to the forward end of the planar support plate, the rear end of the breast plate assembly being laterally movable along the rear portion of the support plate.
In accordance with other aspects of the present invention, the clamping means is adjustably connected between the axle assembly and the breast plate. More specifically, the clamping means comprises a turn buckle assembly having a rearwardly extending threaded member that is pivotally connected to the forward end of the breast plate, and a forwardly projecting threaded member having a clamp at its distal end which is secured to the axle assembly at a fulcrum position.
The base member further comprises an elogated rail assembly that is positioned transversely with respect to the axle assembly for supporting same at substantially the same height as would be the axle assembly if the wheel of the vehicle were in place. A further clamping means may be slidably positioned on the rail assembly forwardly of the axle assembly to prevent forward movement thereof. The bending means in the form of the hydraulic jack may be selectively placed on the breast plate for bending either the front axle beam, the upper torsion arm, or the lower torsion arm.
In accordance with still other aspects of the present invention, there is provided a technique for correcting misalignment of the front end of a vehicle which results from a bent front axle assembly. The technique, which may be performed without dismantling the front end of the vehicle, comprises the steps of clamping the axle assembly at a first position (which defines a fulcrum), and applying a bending force to the axle assembly at a second position that is laterally displaced from the first position. The clamping step more particularly includes the step of preventing forward and rearward movement of the axle assembly, while the force applying step includes the steps of positioning a supporting base underneath the front axle assembly, mounting a jack support member on the base rearwardly of the axle assembly, and operating jack means between the jack support member and the second position at which the bending force is applied. More specifically, the axle assembly comprises a horizontally disposed twin axle beam and a pair of upper and lower torsion arms which extend from each end of the twin axle beam. To prevent twisting, the lower end of the shock absorber of the vehicle is preferably supported on the base member. The jack means may be positioned, alternatively, so as to exert either substantially lateral, upward, or downward pressure on the axle assembly, as the particular correction may require.
BRIEF DESCRIPTION OF THE DRAWINGS
Various objects, features and attendant advantages of the present invention will be more fully appreciated as the same become better understood from the following detailed description thereof when considered in connection with the accompanying drawings, in which:
FIG. 1 is a top, plan view, partly in section, which illustrates a preferred embodiment of the present invention installed on the front end of a motor vehicle during use;
FIG. 2 is a side view of the apparatus illustrated in FIG. 1;
FIG. 3 is an exploded, perspective view which illustrates the basic components of a first preferred embodiment of the present invention utilized in FIGS. 1 and 2;
FIG. 4 is a perspective view illustrating an alternative component which may be utilized in connection with the preferred embodiment illustrated in FIG. 3;
FIG. 5 is another perspective view of the same component illustrated in FIG. 4;
FIG. 6 is a perspective view of yet another and alternative embodiment of a component which may be utilized with the present invention; and
FIG. 7 is another and alternative perspective view which illustrates one of the alternate preferred embodiment components shown in FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views, and more particularly to FIG. 3 thereof, there is illustrated in an exploded, perspective view the main components of a preferred embodiment of the apparatus of the present invention, which may also be utilized in effectuating the technique of correcting misalignment resulting from a bent or otherwise deformed front axle assembly, as will be described in more detail hereinafter in connection with the specific examples illustrated in FIGS. 1 and 2.
The preferred embodiment of the present invention illustrated in FIG. 3 includes a rear support stand 10 and a front support stand 12, which may be substantially identical with one another. Each of the support stands 10 and 12 include a trapezoidal base support portion 14 having an upper horizontal support member 15. Extending upwardly from horizontal support member 15 are a pair of parallel flanges 16 and 18. Positioned in flanges 16 and 18 of each support stand 10 and 12 are a pair of apertures 20 which are aligned and sized so as to receive a pair of positioning and locking bolts 22.
Stands 10 and 12 are adapted to serve as support means for an elongated base rail, indicated generally by reference numeral 24, which is preferably in the form of a U-shaped channel member consisting of a vertical side plate 28, and parallel top and bottom flanges 30 and 32. Positioned longitudinally along the vertical side plate 28 are a plurality of spaced apertures 26 which are designed to receive locking bolts 22 so as to position stands 10 and 12 as desired.
Connected to the rear end of elongated base rail 24 is a base plate 34 which is securely mounted, as by welding, to the top flange 30 of rail 24. Base plate 34 is provided at its rear corners with a pair of mounting slots 36 and 38, and at its front corners with a pair of mounting apertures 40 and 42, for purposes which will become more clear hereinafter.
The preferred embodiment of the present invention also includes a breast plate which is indicated generally by reference numeral 44. Breast plate 44 as illustrated in FIG. 3 is particularly designed to be utilized in connection with correcting bent axle misalignment in connection with the right front end of early model (1948-1969) Volkswagen automobiles. Although the ensuing discussion will be presented in connection with such automobiles as a preferred example and best mode, it should be understood that the principles of the present invention may be easily extended to other makes, models and designs of motor vehicles.
The right front breast plate 44 illustrated in FIG. 3 has a counterpart which is utilized in connection with the correction of bent axle misalignment in the left front ends of early model (1948-1969) Volkswagens, the left front breast plate being illustrated in more detail in FIGS. 4 and 5. The elements of the left front breast plate illustrated in FIGS. 4 and 5 which correspond to those of the right front breast plate 44 illustrated in FIG. 3 are indicated by like primed numerals. Since the left and right front breast plates may be substantially identical mirror images of one another, description of the construction of the right front plate 44 will serve as an adequate description of the left front plate illustrated in FIGS. 4 and 5.
Referring back to FIG. 3, the right front breast plate 44 includes a curved and substantially vertical side plate 46 which is designed in particular to mate with the inner wheel housing or frame assembly of the right front end of 1948 through 1969 Volkswagen automobiles. As mentioned hereinabove, such Volkswagens are characterized by a twin, front axle beam which connects at its approximate mid-point to the header of the frame assembly, a construction which dictated the particular shape of side plate 46.
Breast plate 44 further includes a substantially planar base 48 which extends from the lower edge of curved side plate 46 and which, in use, is supported directly on the base plate 34. Note that the top edge 50 of the curved side plate 46 is also tapered downwardly from front to rear to provide the desired fit with the inner frame of the automobile.
Breast plate 44 further comprises a supplementary support plate 52 which extends from the curved wall 46 and is positioned above and substantially parallel to the base 48. Connected in a substantially perpendicular fashion between plates 48 and 52 are a pair of jack support plates 54 and 56 which are laterally spaced from one another as indicated in the drawing. Extending upwardly from the support plate 52 is a third jack support plate 58 which is angled somewhat with respect to the orientation of jack support plates 54 and 56, for a purpose which will become more clear hereinafter.
From the underside of the rear portion of base 48 extends a mounting ear 60 which is designed to be fitted within aperture 36 in base plate 34. The lower portion of ear 60 includes a pin-receiving aperture 62 for journaling the breast plate 44 against upward movement. Extending also from the underside of base 48 but at the frontal portion thereof is an L-shaped retaining bracket 64 which is adapted to fit over the front edge 41 of base plate 34. Bracket 64 extends rearwardly a sufficient distance so as to permit substantial lateral movement of the front portion of breast plate 44 during use (see FIG. 1).
Positioned in the front-most corners of plates 48 and 52 are a pair of apertures 66 and 68 for receiving a pivot bolt 70.
The left front breast plate illustrated in FIGS. 4 and 5 likewise includes a downwardly depending mounting ear 60' which, during use, may be fitted within slot 38 of base plate 34, while L-shaped retaining bracket 64' fits over the front edge 41 of base plate 34, in a manner analagous to the installation of right front breast plate 44 described above.
The preferred embodiment of the present invention illustrated in FIG. 3 further includes a substantially planar pivot plate 72, of a tear drop shape, which is designed as a bottom support for the shock absorber of the front end of the vehicle during use. The pivot plate 72 includes a shock absorber support cup 74 formed on the free end thereof and a mounting pin 76 extending downwardly and adapted to be fitted within a central aperture 78 formed in the upper flange 30 of rail 24. The pivotable design of pivot plate 72 permits same to be utilized for both left and right front end operations to support the lower end of the shock absorber.
A clamping member is also provided and may preferably take the form of a turnbuckle 80 having one threaded arm 82 which terminates in a ring 84. Ring 84 is adapted to be mounted between plates 48 and 52 in such a fashion so as to receive bolt 70 when inserted through apertures 68 and 66. The other threaded arm 86 of turnbuckle 80 terminates in a clamp member 88 which is designed to grasp a portion of the front axle beam, as will be described in more detail below.
The preferred embodiment of the present invention also may include a front brace member 90 which is adapted to be slidingly received on the front portion of elongated rail 24 by means of upper and lower positioning flanges 92 and 94. The side wall of brace 90 preferably includes an aperture 96 which is adapted to receive a mounting bolt 98 in order to secure the position of brace 90 along rail 24. Brace 90 includes a face plate 100 which is adapted to clampingly secure the front axle assembly, as will be described below.
Referring now to FIGS. 1 and 2, the front axle assembly of an early model (1948-1969) Volkswagen automobile is indicated generally by reference numeral 101. The front axle assembly 101 includes a horizontally extending, front axle, twin beam 110 which has a vertical connecting post 112 positioned substantially as indicated. The front axle assembly 101 also may be said to include an upper torsion arm 102 and a lower torsion arm 104 which extend laterally and rearwardly of both ends of the front axle beam 110 (only the right end is illustrated in the drawing figures). Between the upper and lower torsion arms 102 and 104 is mounted a spindle assembly (not shown) to which is conventionally mounted the hub and drum 106 of the vehicle. Also conventionally provided is a shock absorber 108 which extends between the upper portion of vertical connecting post 112 and a horizontal shock support arm 128 (FIG. 1). Reference numeral 114 indicates the distal end of upper torsion arm 102 which serves as a holder for the upper ball joint 118, while reference numeral 116 indicates the holder for the lower ball joint 120, all of which is conventional.
Reference numeral 122 indicates a bending means preferably in the form of a conventional hydraulic jack having a piston 124 which extends from one end thereof. The feed line for hydraulic jack 122 is indicated by reference numeral 126, while reference numeral 130 in FIG. 1 designates the inner wheel housing of the automobile against which the breast plate 44 rests during use.
In describing the operational technique of the present invention in connection with FIGS. 1 and 2, let it be assumed that misalignment to the front end of the vehicle is being caused by a bent upper torsion arm 102. This may become apparent upon a visual inspection of the front end, in combination with an overly negative camber reading from conventional gauges. When this is determined, the automobile is jacked up and the wheel is removed. Stands 10 and 12 with rail 24 connected are then slid under the automobile to the desired position. The right front breast plate 44 is then installed in base plate 34 by inserting the mounting ear 60 through aperture 36 in plate 34. A pin may be inserted through hole 62 in aperture 60 to secure the breast plate 44 against upward movement. It is noted that the front L-shaped bracket 64 is positioned about and underneath the front edge 41 of base plate 34 so as to permit breast plate 44 some degree of lateral movement.
After the breast plate 44 has been installed, the front end of the automobile is lowered until the axle beam 110 rests upon the upper flangle 30 of rail 24. The height of flange 30 is designed such that, in the position indicated in FIG. 2, the front axle beam 110 is in substantially the same position as it would be if the wheel W were mounted.
Brace 90 may then be secured in place as by bolt 98 such that its face plate 100 bears against front axle beam 110 to prevent forward movement thereof.
Prior to lowering the automobile, the pivot plate 72 is positioned such that cup 74 receives the lower end of shock absorber 108, as indicated most clearly in FIG. 1. Plate 72 is instrumental in preventing undesired downward movement when the bending force is later applied.
After brace 90 is positioned as described above, turnbuckle 80 is installed by positioning bolt 70 through aperture 68, ring 84, and aperture 66, successively, and by positioning clamp 88 about the vertical connecting member 112 of front axle beam 110. The turnbuckle may then be tightened to take up any slack.
Having determined that the upper torsion arm 102 requires straightening, the hydraulic jack 122 is positioned adjacent jack support plate 58 such that the end of piston 124 bears against the socket portion 114 of upper torsion arm 102. When the jack 122 is actuated in the position illustrated, the effect will be to bend torsion arm 102 in such a fashion so as to restore positive camber to the wheel W.
If, on the other hand, it were desired to impart a more negative camber to the wheel W, the base of the hydraulic jack 122 may be placed against either jack support plate 54 or jack support plate 56, while the piston 124 may be positioned against the socket end 116 of the lower torsion arm 104. Still alternatively, the base of jack 122 could be positioned in plate 56 and piston 124 may be positioned to bear against socket 114 so as to impart an even greater bending force to the upper torsion arm 102, which would result in a more positive camber being imparted to the wheel W. Clearly, many variations in the placement of jack 122 are possible, the particular configuration of FIGS. 1 and 2 being shown and described only for the purposes of illustration.
Referring now to FIGS. 6 and 7, there is indicated by reference numeral 150 an alternative breast plate which is designed in particular for use for correcting bent axle misalignment in the front ends of Volkswagen automobiles manufactured since the model year 1970. The breast plate 150 is reversible in that it may be utilized either for the left or right front end of such automobiles. The redesign of breast plate 150 from the pair of breast plates required for the earlier model automobiles resulted from the change in design, as discussed above, of the mounting of the front axle beam to the header assembly of the frame. Since the outer vertical wall 152 of the breast plate 150 must bear against the inner wheel housing or frame of the automobile, the vertical plate 152 is curved, in a somewhat S-shaped configuration, so as to provide the necessary tight fit during use.
Breast plate 150 includes three substantially identical, parallel, and planar horizontal support plates 154, 156 and 158, between which are positioned a plurality of jack support plates 160, 162, 164 and 166. The horizontal support plates 154, 156 and 158 each include a mounting aperture in a front-most corner for receiving a pivot pin 170. Note that the reversible breast plate 150 for the later model Volkswagens is designed to be pivotable at a front portion and laterally movable at its rear, in contrast to the breast plates for the earlier models. The pivot pin 170 may be mounted either in front aperture 40 for the right front end, or the front aperture 42 for the left front end, of the late model automobiles.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | A technique and device for correcting front end misalignment resulting from bent or twisted front axle assemblies which may be performed without dismantling the front end of the vehicle. The apparatus includes means for laterally clamping the axle assembly and means for applying a bending force to the axle at a position laterally displaced from that of the clamping means. A base assembly is utilized to support the axle at its normal height after the wheel has been removed. A novel breast plate is utilized to support the base of a horizontally disposed hydraulic jack which provides the desired camber correction. Preferred embodiments are particularly designed to be utilized with Volkswagen automobiles. | 1 |
BACKGROUND
Related Art
[0001] The present invention relates to secure network communications.
[0002] The ubiquity of Internet connectivity and Web browsers has made Web pages the most common user interface for Internet-enabled applications. Web-based applications now allow users to instantaneously complete transactions that used to take days or weeks to complete. For example, through Web-based applications, one can purchase merchandise, track shipments, check bank accounts, or pay credit card bills with just several mouse clicks.
[0003] However, the wide deployment of Web-based applications also creates new security concerns. In the past few years, HyperText Markup Language (HTML) Scraping has become a common practice. During HTML Scraping, a computer system (HTTP client) impersonates a human user utilizing a web browser to make HTTP requests to an HTTP server. This computer then interprets the data contained in Web pages sent from by the HTTP server and extracts valuable information from the “snapshots” of these Web pages. Furthermore, scraping is not limited only to HTML files, but has also been extended to any files used to create Web pages.
[0004] Although scraping is often used for non-malicious purposes, such as for analyzing a user's Internet behavior, unauthorized eavesdropping is nevertheless intrusive to the user's privacy. Such eavesdropping be a problem when a transaction involves critical financial data, and wherein both the financial institution and the user desire complete privacy and security. Conventional security measures which require a mere username and password are inadequate to solve this problem, because the Web pages displayed on the user's monitor are still based on the code which transports the critical data in plain text. These interactions are typically secured by Secure Socket Layer (SSL) encryption, which can make unauthorized eavesdropping more difficult, but does not solve the problem of an unauthorized agent or system utilizing the user's login credentials, whether acquired legitimately or not, and impersonating the user to initiate an online banking session for the purpose of scraping data for unauthorized purposes.
SUMMARY
[0005] One embodiment of the present invention provides a system that obscures critical information communicated over a network. During operation, the system receives a set of data and produces a file which represents a character in the data with at least one image, thereby avoiding representing the data in plain text and reducing the risk of scraping. The system then communicates the file to a client, thereby allowing the client to present the data using the embedded images.
[0006] In a variation of this embodiment, producing the file involves replacing the character with an image. A character can be an alphabetic character, a numeric character, or a symbol.
[0007] In a variation of this embodiment, producing the file involves dividing the character into a number of portions and replacing each portion with an image. A character can be an alphabetic character, a numeric character, or a symbol.
[0008] In a variation of this embodiment, the system dynamically generates the images used for each session, thereby preventing an unauthorized scraper from acquiring a mapping between one or more images and a character through Optical Character Recognition (OCR).
[0009] In a variation of this embodiment, the system dynamically, that is, non-deterministically, generates the universal resource identifiers (URI's) used to reference the images, thereby preventing an unauthorized scraper from acquiring a mapping between an image and the URI used to reference the image.
[0010] In a variation of this embodiment, the system dynamically generates the images for each character represented by image, thereby preventing an unauthorized scraper from acquiring a mapping between one or more images and a character through OCR.
[0011] In a variation of this embodiment, the system steganographically conceals the file within one or more cover images, thereby further reducing the risk of scraping. Additionally, communicating the file to the client involves communicating the cover images to the client, thereby allowing the client to extract the concealed file.
[0012] In a further variation, the system encrypts the file prior to steganographically concealing the file.
[0013] One embodiment of the present invention provides a system for securing critical information communicated over a network. During operation, the system receives one or more steganographically encoded cover images. The system then extracts the concealed data from the cover images based on a set of pre-determined rules and presents the data to a user.
[0014] In a variation of this embodiment, extracting the concealed data from the cover images involves extracting a file which represents a character in the concealed data with at least one image. Furthermore, presenting the data to the user involves displaying the images which represent the characters in an arrangement that accurately presents the data.
[0015] In a variation of this embodiment, the system decrypts the extracted file prior to presenting the data.
BRIEF DESCRIPTION OF THE FIGURES
[0016] FIG. 1 presents a block diagram of a computer system that obscures critical data contained in a Web page in accordance with an embodiment of the present invention.
[0017] FIG. 2 illustrates a Web page that replaces characters with images in accordance with an embodiment of the present invention.
[0018] FIG. 3 illustrates a Web page that replaces one character with multiple images in accordance with an embodiment of the present invention.
[0019] FIG. 4 illustrates a Web page that uses a cover image to steganographically encrypt critical data in accordance with an embodiment of the present invention.
[0020] FIG. 5 presents a flow chart illustrating the process of obscuring critical Web-page data with images in accordance with an embodiment of the present invention.
[0021] FIG. 6 presents a flow chart illustrating the process of dynamically generating images for obscuring critical Web-page data in accordance with an embodiment of the present invention.
[0022] FIG. 7 presents a flow chart illustrating the process of steganographically encrypting critical data in accordance with one embodiment of the present invention.
[0023] FIG. 8 presents a flow chart illustrating the process of decrypting steganographically-encrypted data in accordance with one embodiment of the present invention.
DETAILED DESCRIPTION
[0024] The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.
[0025] The data structures and code described in this detailed description are typically stored on a computer-readable storage medium, which may be any device or medium that can store code and/or data for use by a computer system. This includes, but is not limited to, volatile memory, non-volatile memory, magnetic and optical storage devices such as disk drives, magnetic tape, CDs (compact discs), DVDs (digital versatile discs or digital video discs), or other media capable of storing computer readable media now known or later developed.
Overview
[0026] Embodiments of the present invention provide a mechanism for displaying critical data to a user without directly displaying the data in plain text within a file that contains a Web page. Such a file can be based on any language which is suitable for creating Web pages. In this description, the terminology “browser-interpretable file” refers to any file based on one or more languages which can be interpreted by a Web browser. Such languages include, but are not limited to: markup languages such as HTML, Extensible Markup Language (XML), and Extensible HyperText Markup Language (XHTML), and scripting languages such as Java Script and VB Script. In one embodiment, the server replaces the critical numeric or alphabetic characters with images. Since most scraping programs can only parse text information, these images can obscure the information carried therein. In a further embodiment, the server can also “slice up” a character into pieces and represent each piece with a separate image. As will be described below, the server can further dynamically generate these images to protect the information against any scraping programs with learning or optical character recognition (OCR) capabilities.
[0027] FIG. 1 presents a block diagram of a computer system that obscures critical data contained in a Web page in accordance with an embodiment of the present invention. A computer system 102 includes a processor 104 , a memory 106 , a storage 108 , and may have coupled to it a display 114 , a keyboard 110 , and a pointing device 112 , as well as other devices. Processor 104 can generally include any type of processor, including, but not limited to, a microprocessor, a mainframe computer, a digital signal processor, a personal organizer, a device controller, and a computational engine within an appliance, or have access to any of the foregoing via a network. Memory 106 can include any type of memory, including, but not limited to, dynamic random access memory (DRAM), static random access memory (SRAM), flash memory, read-only memory (ROM), and memory residing remotely and accessible via a network, volatile, non-volatile, or other memory capable of storing computer readable data.
[0028] Storage device 108 can include any type of non-volatile storage device that can be coupled to a computer system. This includes, but is not limited to, magnetic, optical, and magneto-optical storage devices, as well as storage devices based on flash memory and/or battery-backed up memory, network based storage or other storage media capable of storing computer readable data.
[0029] In one embodiment of the present invention, storage device 108 contains applications 120 and 122 , and a data obscuring program 116 . In other embodiments, the memory may store all or part of applications 120 , 122 , and a data-obscuring program 116 . Data obscuring program 116 further includes a dynamic image generation module 118 , which can dynamically generate images to replace a character in a set of critical data.
Obscuring Critical Data with Images
[0030] One embodiment of the present invention avoids communicating critical data in plain text in browser-interpretable files by embedding and displaying the data as images. For example, a server providing a Web-based financial service can first collect the financial data requested by a user, such as transaction amounts, dates, and account balances, and replace the key characters with individual images. Note that a character can be an alphabetic character, a numeric character, or a symbol.
[0031] The server then assembles a browser-interpretable file which can be, for example, an HTML file and which includes the images with the proper positioning and alignment, so that these images when displayed jointly can accurately present the critical data to the user. Note that the user's machine can parse the browser-interpretable file using a conventional Web browser, and the file can contain links to the image files stores on the server. In one embodiment, a character is represented by a static image file. In this way, the client can avoid multiple downloads by caching the image files.
[0032] FIG. 2 illustrates a Web page that replaces characters with images in accordance with an embodiment of the present invention. In this example, a user's Web browser 200 displays the Web page based on the browser-interpretable file sent by the server. The displayed Web page shows a fictional bank account balance. The critical financial data in this page, such as the balance amounts and account numbers, are displayed as images. FIG. 2 also illustrates a magnified view of the balance amount “1234.79.” Whereas the browser-interpretable file is an HTML file, the HTML code generally displays this amount in plain text:
[0033] <td>$1234.79</td>
[0000] In contrast, in embodiments of the present invention, each digit is displayed with a separate image. For example, the number “3” is displayed with an image 202 , and the decimal point is displayed with an image 204 . The corresponding HTML code can be:
[0000]
<td>$<img src=“1.png”><img src=“2.png”>
<img src=“3.png”><img src=“4.png”>
<img src=”dot.png”><img src=“7.png”>
<img src=“9.png”></td>
[0034] When the server replaces the character with static images, a scraping program can still derive an image-to-character mapping by applying OCR to each individual image. One way of preventing OCR-based scraping is to divide a character into multiple pieces, and to represent each piece with an image.
[0035] FIG. 3 illustrates a Web page that replaces one character with multiple images in accordance with an embodiment of the present invention. A user browser 300 displays a Web page based on the browser-interpretable file received by the user's machine. The Web page displays critical financial information as images. However, a character, such as the number “7” as is shown in the magnified view, is divided into six portions and presented by six corresponding images 312 - 322 . Since an image does not represent an entire character, a scraping program cannot establish an image-to-character mapping by performing OCR. Whereas the browser-interpretable file is an HTML file, a corresponding HTML code to display the number “7” can be:
[0000]
<td><img src=“7_upperleft.png”>
<img src=“7_upperright.png”><br>
<img src=“7_middleleft.png”>
<img src=“7_middleright.png”><br>
<img src=“7_lowerleft.png”>
<img src=“7_upperright.png”></td>
[0036] In one embodiment, the server can further obscure the browser-interpretable file by dynamically generating the images and by assigning each image a different file name. For example, the server can generate one set of images to represent the characters in one session, and can expire these images when the user closes the session. In a further embodiment, the server can dynamically generate the images for each character which is replaced by images. That is, the same character can have different sets of representation images if the character is displayed at different locations. In this way, the server can minimize the risk of a scraper acquiring the image-to-character mapping. In addition, instead of generating actual image files, the server can dynamically, that is, non-deterministically, generate the universal resource identifiers (URI's) which are used to reference the images in the browser-interpretable file. In this way, the server can prevent an unauthorized scarper from acquiring a URI-to-image mapping. For example, an HTML code that displays the number “7” by using six dynamically referenced images can be:
[0000]
<td><img src=“2da09dj3.png”>
<img src=“14fzs0dk.png”><br>
<img src=“cv24iaf3.png”>
<img src=“235bhgc0.png”><br>
<img src=“2tfb054a.png”>
<img src=“xcv30ik2.png”></td>
Secure Data Communication by Steganographical Encryption
[0037] Sometimes, a user may desire not only obscurity but also security of the critical data communicated over the network. In one embodiment of the present invention, the server employs steganographical encryption to conceal the critical data in another set of “cover-up” data. For example, the server can include an irrelevant image in the browser-interpretable file. The user's machine can extract concealed data from the image based on a secret key shared with the server. On the other hand, an unauthorized scraper only receives the cover image but has no way of knowing how to extract the concealed information.
[0038] FIG. 4 illustrates a Web page that uses a cover image to steganographically encrypt critical data in accordance with an embodiment of the present invention. In this example, an unauthorized scraper intercepts an browser-interpretable file sent from a server to a user. However, the image displayed by browser 402 does not reveal any critical data, because the scraper does not have the key to decrypt the image. The critical data can be concealed in the cover image in numerous ways. For instance, the critical data can be stored in the unused color bits for each pixel of the image.
[0039] On the other hand, when the intended user's Web browser 404 receives the browser-interpretable file, browser 404 first uses the decryption key to decrypt the information encoded in the cover image. Then, browser 404 displays the critical data to the user.
[0040] In further embodiments, the server can increase the security level by obscuring or encrypting the data concealed in the cover image. For example, the server can conceal an HTML file in the cover image. In this HTML file, the critical data are represented by images, as is described above in conjunction with FIGS. 2 and 3 . Furthermore, before concealing the data in the cover image, the server can also encrypt the data using, for example, a public key of the user. In this way, only the user can extract and then decrypt the data using its private key. Other methods of obscuring or encrypting the data can also be used in conjunction with the steganographical encryption.
Exemplary Implementation
[0041] FIG. 5 presents a flow chart illustrating the process of obscuring critical Web-page data with images in accordance with an embodiment of the present invention. During operation, the system at a server starts by receiving the critical data (step 502 ). The system then formulates a tentative Web page which presents the received critical data (step 504 ). Subsequently, the system replaces the characters in the tentative Web page with images (step 506 ).
[0042] Next, the system generates a final Web page with embedded links to the images and the proper arrangement of the images to ensure that the images can be displayed properly on a user's monitor (step 508 ). The server system then sends the final Web page to the client (step 510 ).
[0043] FIG. 6 presents a flow chart illustrating the process of dynamically generating images for obscuring critical Web-page data in accordance with an embodiment of the present invention. During operation, the server system starts by receiving critical data (step 602 ) and formulating a tentative Web page which presents the received data (step 604 ). The system then dynamically generates the image files to replace characters on the tentative Web page (step 606 ).
[0044] Subsequently, the system generates a final Web page with embedded links to the dynamically generated images to obscure the critical data (step 608 ). The system then sends the final Web page to the client (step 610 ).
[0045] FIG. 7 presents a flow chart illustrating the process of steganographically encrypting critical data in accordance with one embodiment of the present invention. During operation, the server system first receives the critical data (step 702 ). The system then steganographically encrypts the critical data in one or more cover images (step 704 ). Next, the system generates a Web page which contains the cover image (step 706 ). The system subsequently sends the Web page to the client (step 708 ).
[0046] FIG. 8 presents a flow chart illustrating the process of decrypting steganographically-encrypted data in accordance with one embodiment of the present invention. During operation, the client system receives a Web page containing a cover image from the server (step 802 ). The system then decrypts the cover image to retrieve the critical data (step 804 ). Next, the system presents the critical data in a final Web page to a user (step 806 ).
[0047] The foregoing descriptions of embodiments of the present invention have been presented only for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the forms disclosed. Accordingly, many modifications and variations will be apparent to practitioners skilled in the art. Additionally, the above disclosure is not intended to limit the present invention. The scope of the present invention is defined by the appended claims. | One embodiment of the present invention provides a system that obscures critical information communicated over a network. During operation, the system receives a set of data and produces a file which represents a character in the data with at least one image, thereby avoiding representing the data in plain text and reducing the risk of scraping. The system then communicates the file to a client, thereby allowing the client to present the data using the embedded images. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. provisional application Ser. No. 60/882,636, filed Dec. 29, 2006, and 60/890,107, filed Feb. 15, 2007, which is incorporated herein in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to refrigeration mechanisms and, in particular, to such mechanisms that include electrically powered actuators.
2. Description of the Related Art
Modern refrigeration mechanisms, such as refrigerator/freezer units, have electrically powered actuators that perform a variety of functions. An example is an ice maker/dispenser. Normally, electrical motors perform functions such as operating valves to supply water to the ice maker, moving a rod or rack to eject ice that has been frozen from supplied water, and moving other structure to move, alter, or direct ice pieces to an ice delivery or dispensing chute.
In the case of an ice maker/dispenser, the user normally must manually push a button with a finger or move a glass or container against a lever to actuate the motors to dispense ice down the chute. In some models, the user can also manually push a button to select between ice cubes or crushed ice, and in some instances shaved ice. Normally, once actuated, the dispenser operates until the user releases the button or lever. In some cases, the dispenser motor continues until automatically stopped by a timer.
In either of these cases, there are situations where it may be desirable to automatically stop the dispensing motor even if the user has instructed it to continue. For example, if ice jams or clogs the ice dispensing chute, the user may continue to try to operate the dispensing motor. Ice would back up and potentially damage the system. Additionally, if a foreign object (a non-ice object) enters the chute, it would be advantageous to automatically detect the same and stop operation of the dispensing motor until the situation can be resolved.
Furthermore, maintenance is some times performed on the ice chute, or at or near the ice chute. It could be advantageous to disable the dispensing motor automatically. There are other reasons to stop moving parts, such as are obvious to those skilled in the art.
There can be other actuators in the form of motors, valves, fans, etc. that are electrically powered and may have moving parts or cause certain functions where it would be advantageous to have some sort of backup or failsafe automatic protection to disable or shut off the actuator for unwanted conditions.
SUMMARY OF THE INVENTION
It is therefore a principle object, aspect, feature and/or advantage of the present invention to provide an apparatus, method, and system which improves over or solves the problems and deficiencies in the art.
Further objects, aspects, features, and/or advantages of the present invention include, but are not limited to, an apparatus, method, or system for automatically detecting and disabling or turning off an electrically powered actuator in a refrigeration mechanism which:
a. prevents tampering, damage, or breakage of components of the refrigeration mechanism;
b. detects the difference between conditions indicative of an unwanted condition from a wanted condition for the refrigeration mechanism;
c. is robust, and durable, particularly in the environment of a refrigeration unit, where there can be a range of temperatures and moisture content;
d. detects ice and non-ice objects;
e. does not require contact with an object to sense an unwanted condition; and
f. is efficient and relatively economical.
A method according to one aspect of the invention comprises providing an electrically-powered actuator in a refrigeration mechanism, sensing the presence of an object along or a near sensing location, and turning off or disabling the actuator if the sensed presence of an object is indicative of an unwanted condition.
An apparatus according to an aspect of the present invention comprises a refrigeration mechanism with an electrical powered actuator, a sensor producing an electrical output signal in response to sensitivity to a measured property, the measured property comprising presence of an object at or near a sensing location; a control operatively connected to the sensor and the actuator, the controller issuing an instruction to stop or disable operation of the actuator based upon a parameter of the measured property of the sensor.
Another aspect of the present invention comprises a method or apparatus where the measured property comprises presence of an object at or near the sensing location and a parameter of the measured property is length of time of presence of the object at the sensing location.
A further aspect of the present invention is an apparatus or method as above described wherein the measured property of the sensor is transduced by measuring attenuation of the energy or agent capacitance of an electromagnetic field.
Another aspect of the present invention is a refrigeration mechanism comprising an ice maker including an electrically powered actuator, a dispensing chute, a sensor producing an electrical output signal in response to a measured property comprising presence of an object along or near an ice dispensing pathway defined by the ice dispensing chute, a controller connected to the sensor and actuator and adapted to issue an instruction to stop or disable operation of the actuator based on cumulative time of presence of an object at or near the ice dispensing pathway.
These and other objects, aspects, features, or advantages of the present invention will become more apparent with reference to the accompanying specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevation view of a refrigeration mechanism comprising a side-by-side refrigerator/freezer with an ice and water dispenser.
FIG. 2 is an enlarged isolated perspective view of an ice dispensing chute for delivering ice to the dispensing station of the refrigerator of FIG. 1 , further showing diagrammatically an optical sensing system in operative communication with a controller and actuator (an ice maker/dispenser) of the refrigeration mechanism of FIG. 1 .
FIG. 3 is an enlarged side sectional view of the ice and water dispensing station of the refrigeration mechanism of FIG. 1 showing schematically an ice maker above the ice dispensing chute.
FIG. 4 is a perspective view of the exit opening of an alternative embodiment of an ice dispensing chute at a dispensing station.
FIG. 5 is a block diagram of electrical and electronic components for the optical sensing system of the simplified diagram of FIG. 2 .
FIG. 6 is a flow chart of software programming for operation of the system of FIG. 5 .
FIG. 7 is a diagrammatic illustration of one mode of operation of the optical sensing system of FIG. 2 .
FIG. 8 is a diagrammatic illustration of another operating mode of the optical sensing system of FIG. 2 .
FIG. 9 is a still further mode of operation for the optical sensing system of FIG. 2 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
For a better understanding of the invention, one form the invention can take will now be described in detail. Frequent reference will be taken to the appended drawings. Reference numerals or letters will be used to indicate certain parts or locations in the drawings. The same reference numerals or letters will be used to indicate the same parts and locations throughout the drawings unless otherwise indicated.
This exemplary embodiment of the invention will be described in the context of implementation with an ice maker/dispenser (indicated generally at reference numeral 30 in FIG. 1 ) of a side-by-side refrigerator/freezer (indicated generally by reference numeral 10 in FIG. 1 ). Refrigerator/freezer 10 has a housing 12 that defines, on its left side, a freezer compartment 14 that is accessible by door 18 and, on its right side, a refrigeration compartment 16 accessible by door 20 .
Door 18 includes ice/water dispensing station 22 , allowing a user to obtain ice or water through door 18 without opening either door to refrigerator/freezer 10 . Such ice/water dispensers are commonly available in a variety of commercial, residential refrigerator/freezer appliances. One example is Whirlpool® Gold® Models, Whirlpool Corp., Benton Harbor, Mich., USA.
In this exemplary embodiment, dispensing station 22 includes a recessed chamber 23 and a floor on which a container such as a glass or cup can be supported. User control panel 24 allows manual selection between modes of operation. In this example, control panel 24 could communicate with a controller 25 (in this example controller 25 could be housed behind user control panel 24 ) which is, in turn, adapted to control a variety of operations of refrigerator/freezer 10 . For example, dispensing levers 26 (for ice) and 28 (for water) could be operatively connected to electrical switches such that when a glass is pushed against either lever, controller 24 would recognize and actuate the appropriate component to provide the selected product (ice or water).
FIG. 1 shows in ghost lines the position of an ice maker/dispenser 30 (at least partially built into the back of door 18 ). An ice bucket or container 32 is positioned above ice dispenser/crusher/shaver 34 , which can be actuated by motor 36 that is controlled by controller 24 . Indicated diagrammatically at reference numeral 38 , an ice dispensing chute 38 has an inlet or feed end 40 beneath the ice dispenser 34 and funnels to an exit or dispensing end 42 right above ice dispensing lever 26 at dispensing station 22 . In this manner, ice from ice maker 30 can be accumulated and stored in ice bucket 32 . Upon actuation of motor 36 by controller 24 , ice, in the form selected by the user at control panel 24 , is delivered into the top or inlet end 40 of ice dispensing chute 38 and then falls and is focused by gravity and chute 38 to exit dispensing end 42 of chute 38 , usually into a glass or container pressed against ice dispensing lever 26 .
Motor 34 would continue operation and continue to feed ice through chute 38 so long as ice dispensing lever 26 is depressed. The dispensing would cease and operation of motor 34 would cease when the user releases pressure against ice dispensing lever 26 .
In this example, the user can select from control panel 24 whether the ice is delivered in cube form as it exists in ice bucket 32 , or whether it is crushed or perhaps shaved by means well known in the art caused by operation of motor 34 .
The foregoing is conventional in the art.
FIGS. 2 and 3 illustrate an apparatus according to one aspect or exemplary embodiment of the present invention. An optical sensing system (referred to generally as reference numeral 50 in FIG. 2 ) includes light energy emitter 52 and a complementary light energy detector 54 aligned on opposite sides of ice dispensing chute 38 . Emitter 52 directs a light energy beam across the interior of chute 38 . System 50 is in a normal configuration so long as nothing blocks or attenuates beam 56 below a threshold. However, if an object blocks or sufficiently attenuates beam 56 , optical sensing system 50 issues an output signal to controller 25 . Controller 25 therefore is provided with the information that attenuation of beam 56 exceeds a predetermined calibrated threshold and assumes the presence of an object at that location of chute 38 . According to a programmed algorithm, controller 25 then monitors optical sensing system 50 . If a parameter of the algorithm occurs, controller 25 can automatically disable or discontinue operation of motor 36 . The algorithm will be described in more detail later.
It can therefore be seen that the inclusion of optical sensing system 50 provides an automated method of detecting the presence of an object in ice dispensing chute 38 and providing controller 25 with information it can use to determine if an unwanted condition in chute 38 exists, such that automatic shutoff of dispensing motor 36 is indicated.
FIGS. 2 and 3 illustrate emitter and detector pair 52 / 54 positioned intermediate between entry opening 40 and exit opening 42 of chute 38 . More particularly, it is indicated as being closer to exit end 42 than entry end 40 . It is to be appreciated, however, that the emitter/detector pair 52 / 54 could be placed anywhere along entry 40 , which defines an ice dispensing pathway.
FIGS. 2 and 3 illustrate an alternative placement for the emitter/detector pair. An emitter/detector pair 52 ′/ 54 ′ could be placed outside of chute 38 . In FIG. 2 , structure (fins 44 and 436 ) extend away from exit opening 42 . Alternative emitter/detector pair 52 ′/ 54 ′ could be placed slightly spaced apart from exit end 42 of chute 38 . It can be appreciated the emitter/detector pair could be placed almost anywhere along the dispensing path, and, as indicated, inside or outside of chute 38 .
FIG. 4 shows an alternative embodiment of an ice dispensing chute (see reference numeral 38 ′). Its dispensing or exit end 42 ′ is square-shaped. Emitter 52 /detector 54 can be inside chute 38 . Housing fins 44 and 46 extend from exit end 42 ′. Alternative emitter/detector pair 52 ′/ 54 ′ could be placed so that its beam 56 ′ is actually spaced away from but in front of the exit end 42 ′. The sensor normally will be placed somewhere along or near the dispensing chute or dispensing pathway. A purpose for placing it in the position shown for emitter 52 ′/detector 54 ′ is illustrated at reference numbers L 1 and L 2 in FIG. 3 . Placement of sensor pair 52 ′/ 54 ′ outside dispensing end 42 of chute 38 would shut motor 36 off sooner upon detection of an unwanted object from the direction of dispensing chamber 23 because it would “see” or sense the object sooner than if sensor pair 52 / 54 (inside chute 38 ) were used. It would start the timing period sooner, because it would trigger when the object is sensed at the lower end of the length L 2 . If pair 52 / 54 were used, it would not trigger until the lower end of distance L 1 . The triggering of the timing of presence of the object would be delayed the time it takes for the object to move the distance L 2 minus L 1 . On the other hand, if sensor pair 52 / 54 inside chute 38 is used, it might be advantageous to place sensor pair 52 / 54 near the exit 42 of chute 38 for detecting ice jams, because it would minimize of amount of ice stuck in the chute and, therefore, minimize the amount of time to clean the jam. The jam would likely start at the narrowest part of the chute (near exit end 42 ) and, thus, placement of sensor 52 / 54 nearer that end 42 would trigger the timing algorithm sooner and likely result in a smaller ice jam before motor 36 is turned off.
FIG. 5 shows a block diagram form of an electrical circuit according to this exemplary embodiment. Controller 25 can be any of a variety of commercially available microprocessors or programmable logic controllers (PLCs). Controller 25 can be the programmable device that controls other functions of the refrigerator/freezer 10 or a dedicated controller.
For example, not only could emitter and receiver 52 and 54 be operatively connected to controller 25 , ice dispenser lever or switch 26 (as well as user-selectable “cubes”, “crushed” or “shaved” buttons on control panel 24 ) can be inputs to controller 25 . An additional input could be a door open switch 27 which could let controller 25 know if door 18 is open. If so, controller 25 could, in one embodiment, disable or turn off motor 36 regardless of optical sensing system 50 .
Transmitter 52 and receiver 54 (or 52 ′ and 54 ′) can be any of a number of commercially available photo emitter/detector pairs. Examples of photo sensors and photo emitter/detector pairs can be found at U.S. Pat. No. 6,314,745. In this embodiment, the pair 52 / 54 would be sealingly positioned along chute 38 . They would not materially obstruct flow of ice in any form along chute 38 but would have clearance to project and receive beam 56 across chute 38 (or beam 56 ′ between items 52 ′ and 54 ′). Electrical connections and wiring from the emitter and receiver to system 50 can be insulated and sealed from moisture. System 50 can include components or circuitry that is compatible and correlated with emitter and receiver 52 and 54 to provide sufficient operating power to emitter 52 . System 50 can be calibrated to trigger when light energy detected at detector 54 is attenuated below a certain threshold level. System 50 , on that trigger, would issue an output signal readable by controller 25 as indicating a sensing of presence of an object between emitter/receiver pair 52 / 54 .
FIGS. 6-9 illustrate a method of operation of the apparatus described above.
As indicated at FIG. 6 , when power is provided to refrigerator freezer 10 , controller 25 would check if freezer door 18 is closed (e.g., is switch 27 closed?) (see step 102 ). If not, dispenser motor 36 would be disabled (step 105 ) even if a user pressed ice dispenser switch 26 .
However, if switch 27 is closed, indicating door 18 is closed, the program waits until ice dispenser switch 26 is pushed on (step 104 ). If so, dispenser motor 36 is switched on (step 108 ). However, the algorithm 100 monitors light sensor receiver 54 . If a signal from sensor 54 is received corresponding to sensing of the presence of an object (step 110 ), a timer in incremented (step 112 ). If sensor 54 indicates presence of an object for greater than X seconds (step 114 ), dispenser motor 36 is made inoperable or turned off (step 106 ). In this embodiment, X is a value between approximately 1 and 2 seconds.
The algorithm will continue to check sensor 54 after an initial indication of the presence of an object, but also continue to operate dispenser motor 36 (steps 108 , 110 , 112 , and 114 ) until the X seconds limit is reached. Controller 25 would issue an instruction to deactivate or turn off motor 36 (step 106 ) if T>X is reached. The system assumes an object is in chute 38 and has remained there for over the X seconds. The system assumes this is an unwanted condition and turns motor 36 off so no moving parts in ice dispenser 30 are moving and ice does not continue to be dispensed.
On the other hand, note that if there is an initial sensing of presence of an object by sensor 54 (step 110 ), the algorithm increments timer (step 112 ), but if the object discontinues to be sensed before expiration of X seconds, dispenser motor 36 (step 108 ) would continue to operate. There would be no interruption in dispenser motor 36 . The system assumes there is no unwanted condition if the object is not present for greater than X seconds (e.g., 1 to 2 seconds). An example would be falling ice cubes, which might block beam 56 , but not for more than a fraction of a second.
Once the sensor beam is indicated as unblocked, the timer would be reset to 0 (step 116 ). The algorithm would continue to operate dispenser motor 36 (step 108 ) until either the ice dispenser switch 26 is released (step 104 ) or the refrigerator door is open (step 102 ).
As can be appreciated, algorithm 100 of FIG. 6 can provide the following function. If the user begins operation of the ice dispenser motor 36 by depression of lever 26 , as illustrated diagrammatically in FIG. 7 , in normal operation the ice (here ice cubes) would pass through beam 56 . The value of time X would be selected or calibrated so that it is large enough that ice cubes, shaved ice, or crushed ice can pass in pieces in a relatively continuous fashion through beam 56 without creating a false stop. On the other hand, as illustrated in FIGS. 8 and 9 , a solid, larger individual object (e.g. a knife, fork, spoon— FIG. 8 ) or a collection of non-moving objects (e.g. ice cubes, shaved ice, or crushed ice that is plugged in the ice chute— FIG. 9 ) would trigger a dispenser motor stoppage if its presence is sensed for >X seconds.
In the preferred embodiment, time X can be between approximately 1 and 2. This is believed to be adequate to meet the rule. A somewhat continuous flow of ice cubes or even crushed or shaved ice would not be deemed by the system as having a continuous beam blockage for greater than that number of seconds as there would generally be spaces where the light detector 54 would see beam 56 between those pieces. On the other hand, insertion of silverware or a blockage of cubes, crushed ice, or shaved ice, would create normally a continuous block for greater than that number of seconds and cause automatic stoppage of the dispenser motor and continued dispensing of ice.
As can be appreciated, the algorithm is intended to differentiate between non-wanted events and wanted events. A wanted event is normal dispension of ice cubes, crushed ice, or shaved ice. An unwanted event can be, for example, the presence of objects such as shown in FIGS. 8 and 9 .
As can be appreciated by those skilled in the art, the foregoing exemplary embodiment is by way of example only and not by way of limitation.
For example, a variety of sensors could be used. One example is a capacitive sensor. It could be calibrated to sense the presence of an object, e.g., whether silverware, or clogged ice. Capacitive sensors are well known and commercially available. An example of such technology can be found at U.S. Pat. No. 7,084,643. Other types of sensors could include but are not limited to thermal, electromagnetic, optical, non-ionizing, acoustic, or motion sensors.
Variations obvious, after the benefit of this disclosure, to those skilled in the art will be included within the invention. | An apparatus, method, and system for automatically turning off an electrically powered actuator in a refrigeration mechanism upon detection of an unwanted condition. In one aspect of the invention, the electrically powered actuator can be the motor of an ice maker/dispenser. The detection can be accomplished by sensing the presence of an object along or near an ice dispensing pathway from the ice maker/dispenser. The unwanted condition could be the presence of the object for more than a preset time period. This would allow to distinguish between an unwanted object such as silverware or clogged ice versus a wanted object such as flowing ice cubes, crushed ice, or shaved ice. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates generally to marking systems, and more particularly relates to a versatile tool which is adapted to be used in conjunction with a measuring tape to enable a worker to make accurate alignment marks while engaging in the arts of carpentry, drywall installation, etc.
[0003] 2. Background Art
[0004] Carpenters, drywall installers, sheet metal technicians, steel fabricators and the like often rely on aides to assist them in drawing lines and circles. A common technique used by carpenters or others for marking a line on a work piece is to clamp a measuring tape between two fingers at the desired length relative to an edge of the work piece and then slide their fingers along the edge of the workpiece while holding a pencil with the other hand at the end of the tape, drawing a line along the top of the work piece as the tape is moved. This, however, is dangerous because of splinters and/or burns that occur while sliding one's fingers along a edge in direct contact with the workpiece . Also, the tape measure may not always be at right angles to the edge of the workpiece with the result of there being an error as to the correct location for the line end or variation in the straightness of the line.
[0005] The typical tape measure device includes a thin, flexible, narrow steel tape which has a slight upward transverse curvature and typically retractably unrolls from a slot in a compact housing. the tape is provided with a short metal end flange which serves the dual function of preventing the free end of the steel tape from entering the housing of the tape measure through the slot in the housing when retracted and providing the user of the tape measure with a means of conveniently grasping the free end of the tape when manipulating the tape.
[0006] Various complex structures have been disclosed for marking and even cutting work pieces. a number of built in or retrofit constructions have been developed for association with tape measuring devices to carry out the simultaneous measuring and marking of a workpiece. These devices are used to make a mark on a workpiece at a given length by attaching the marking device to the case of the tape measure and creating the mark by moving the case back and forth.
[0007] A number of prior art patents reveal attempts to provide devices which can assist the workman in marking and cutting along a workpiece. Examples of such attempts are disclosed in:
Patent No Issue Date Inventor USA RE. 36,887 Oct. 3, 2000 Jay Goldman 3,192,630 Jul. 6, 1965 L. H. Dineson 4,890,393 Jan. 2, 1990 Joseph D. P. St. Jean 5,172,486 Dec. 22, 1992 Arthur Waldherr 5,295,308 Mar. 22, 1994 Mark D. Stevens 6,070,338 Jun. 6, 2000 Michael Garity 6,108,926 Aug. 29, 2000 Robert A. Fraser 6,115,931 Sep. 12, 2000 Stephane Arcand 6,212,787 B1 Apr. 10, 2001 Thomas J. Dixon 6,223,443 B1 May 1, 2001 Danny L. Jacobs FOREIGN JP401267100A Oct. 24, 1989 Takayoshi Oitate
[0008] None of the teachings in any of these patents, however, provide a simple, easy-to-use, add on to existing retractable measuring tapes which provides a multiple of features in a single system. Further, it is believed that prior inventions intended to address the shortcomings present in the relevant industries are not widely available because of manufacturing difficulties and the matter in which the device is operated.
[0009] U.S. Pat. No. 6,212,787, to Dixon discloses a tape measure having a writing instrument mounting structure at the free end of the tape. Dixon does not, however, provide any means whatsoever for assisting the operator in sliding the tape measure housing along the edge of a workpiece during a measurement, marking or cutting operation.
[0010] U.S. Pat. No. 6,223,443, to Jacobs discloses a pattern developing tool having a belt clip to which can be mounted a writing instrument adjacent the tape housing and a pivotal bracket and marker holder adapted to be attached to the free end of the tape. Jacobs also does not disclose any means for assisting the operator in sliding the tape measure housing along the edge of a workpiece.
[0011] Furthermore, the belt clip of Jacobs does not appear to be universally adaptable to the wide variety of makes of retractable tape measure devices on the market today.
[0012] U.S. Pat. No. RE36000,887 to Goldman discloses a custom-made tape measure and marking device in which a secondary tape free and is mounted to the primary free end of the tape by inserting a slot on the secondary free end into a corresponding loop fixedly mounted to the primary free end of the tape, and a pivotally disposed element connected to the housing for protecting the index finger of the hand of a person holding the casing and moving it along an edge of the workpiece. The Goldman device must be manufactured with the custom features disclosed, and therefore cannot be retrofit on any of the existing wide variety of devices on the market. Moreover, the Goldman device lacks most of the features of the instant invention.
[0013] U.S. Pat. No. 6,115,931 to Arcand discloses a tape measure device with a measuring tape blade having a swivelling end assembly adapted to hold an attachment rotatably with respect to the free end of the tape. The Arcand device, like that of the two previous devices, must be custom made as it lacks the downwardly depending flange found on virtually all tape measure on the market today.
[0014] U.S. Pat. No.6,108,926 to Fraser discloses a retractable tape measure having a custom tape end assembly adapted to be fixedly connected via a mechanical screw-type fastener to the free end of the tape having a sharp pointed hook shiftably supported thereto. In addition, the Fraser device does not include any means for assisting the user in sliding the housing along the edge of a workpiece.
[0015] U.S. Pat. No. 6,070,338 to Garity discloses a device for measuring and cutting sheet rock which includes a tape free end-mounted edge guide which has a smooth surface for sliding the edge along the edge of a workpiece and a tape which is of substantially larger width than normal readable in both directions. The edge guide is adapted to allow a knife blade to be held by hand by the operator there against so as to allow the sheet rock to be cut along a line parallel to its edge. Garity does not disclose any means for assisting the user in sliding the housing along the edge of the workpiece, and requires the use of another type of custom made tape free end.
[0016] U.S. Pat. No. 5,295,308 to Stevens discloses a measuring, cutting and marking tool incorporating a tape measure having a case with a holder for a marking or cutting device integrally formed thereon. The Stevens device discloses a sliding member which is a custom made arrangement permanently mounted to the free end of the tape and which is used to slide the free end of the tape along the edge of the workpiece which the writing instrument attached to the tape measure housing is used to mark a line parallel to the edge of the workpiece. The Stevens device is cumbersome in that it is easier to slide the housing along the edge of the workpiece than the end of the tape due to the inertia created by the moving tape housing during marking operations.
[0017] U.S. Pat. No. 5,172,486 to Waldherr discloses a fixture for use with a retractable tape measure having a tab at the free end of the tape perpendicular to the tape. The fixture has a base with opposed sidewalls at least one of which defines a recess for receiving the tape end tab therein. Like the device of Stevens, the Waldherr device requires the writing instrument to be attached to the housing while the free end of the tape is slid along the edge of the work piece.
[0018] U.S. Pat. No. 4,890,393 to Saint Jean discloses a measuring tape guide attachment having a guide for marking which attaches to the opening or slot in the housing through which the measuring tape is extended and retracted. The attachment, however, is overly long and barely extends into the tape measure housing, rendering it susceptible to the torsional forces exerted upon the writing instrument which is hand-held against the free end of the tape during the marking operation.
[0019] U.S. Pat. No. 3,192,630 to Dineson, discloses a tape measure device which employs a guard member having an arm that is fixedly attached to the exterior of the tape measure housing and a downwardly depending, narrow, flat portion adapted to slide along an edge of a workpiece. The Dineson device also includes a writing or cutting tip adapted to be removably attached to the free end of the tape. The Dineson device does not, however, provide a stabilizing element on the housing-mounted guide, and the guide can be easily dislodged from connection to the housing due to its attachment by only a small spring element. Furthermore, the Dineson device does not provide the additional inventive features disclosed in the invention herein.
[0020] Japanese Patent No. 4,0126,7100A discloses, as best can be discerned, a tape measure device having a tape which assumes an inflexible shape when drawn out from the housing, and a support for attaching a writing instrument to the free end of the tape. The device disclosed in the Japanese patent is only directed toward drawing an arc on a workpiece and requires a custom tape element of which the inventors of the instant invention are unaware.
[0021] Accordingly, it is an object of this invention to provide a marking or cutting system which is simple and inexpensive to manufacture and easy to use.
[0022] It is also an object of this invention to provide a marking system having a variety of features but which, in combination, will satisfy the needs of the average construction worker needing to mark lines and arcs accurately, quickly and with a minimum of manual labor.
[0023] It is a further object of this invention to provide a clip which connects through a slot in a tape measure housing parallel to an extended measuring tape, which has alignment extensions for greatly facilitating the visual identification of the markings on the tape, a sliding facilitator, and a variety of marking or cutting tips adapted to be mounted to either the clip or a standard depending flange at the free end of the tape.
[0024] Further objects of this invention will become apparent as the description proceeds.
SUMMARY OF THE INVENTION
[0025] The invention is directed to a system for permitting highly accurate marking to be made upon a workpiece such as drywall, plywood, etc including a clip comprised of a body member, a tongue member attached at right angles thereto, and a spring member, the tongue member and spring member cooperating to retain the tongue member within a slot of a tape measure housing. The tongue member may be contoured to conform to the arcuate shape of a measuring tape. A pointed attachment will also be provided which is adapted to be attached to the distal end of the measuring tape to act as a measuring tape distal end anchor or writing implement. The pointed attachment and clip are adapted to cooperate to permit a user of the measuring tape and housing to draw arcs on the workpiece or straight lines on a workpiece parallel to an edge of the workpiece.
[0026] This description, together with the objects of the invention and the various features of novelty which characterize the invention are pointed out with particularity in the claims annexed hereto and forming a part of this disclosure. For a better understanding of the invention, its operating advantage is in the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated at least one preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] [0027]FIG. 1 is a perspective view of the system of the preferred embodiment of this invention.
[0028] [0028]FIG. 2 is a side elevational view of a component of the system.
[0029] [0029]FIG. 3 is a front cross-sectional view of the component shown in FIG. 2.
[0030] [0030]FIG. 4 is a perspective view of an additional feature of the invention.
[0031] [0031]FIG. 5 is a top plan view of the clip of the instant invention connected to a tape measure housing.
[0032] [0032]FIG. 6 is a cross-sectional side elevational view of the instant invention attached to a tape measure housing.
[0033] [0033]FIG. 7 is a perspective view of a modified component of the invention.
[0034] [0034]FIG. 8 is a side elevational view of the component shown in FIG. 5.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0035] [0035]FIGS. 1 through 3 disclose the preferred embodiment of the invention which includes a clip 20 adapted to be releasably attached to a tape measure housing 24 . The tape measure housing 24 can be of any of the multitude of designs available today having an interior cavity adapted to house a semi-flexible measuring tape 25 in spooled orientation which is deployed and retracted though an opening slot 26 . Such tape measures typically have a braking or locking device actuated by a button 29 or the like, and may have such accessories as a belt clip 31 . the position, location and operation or features of the tape measure may vary without affecting the scope of the invention. Tape 25 is provided with spaced demarcations for purposes of measuring distances, and has a distal end 40 bearing a hook-shaped member 42 which can be grasped to withdraw the tape 25 from housing 24 , and can be placed against a surface or edge to allow one-handed retraction of the tape from the housing, as is well known with devices of this type.
[0036] Hook member 42 typically defines an elongated through-slot 44 .
[0037] Clip 20 has a generally horizontally disposed tongue or finger 50 , which may (or may not depending upon the shape of the tape) have an arcuate shape when viewed elevationally to conform to the shape of a standard measuring tape 25 . Finger 50 is connected to the remainder of clip 20 at a point where a pair of left and right alignment tabs 52 , 54 are provided. Alignment extensions or tabs 52 , 54 extend generally beyond the outer edges 27 , 28 of tape 25 to act as alignment guides, making it easier to ascertain the point at which demarcations on the tape align with clip 20 for purposes which will be apparent herein below.
[0038] Clip 20 also includes guide plates 56 , 58 which end in a slight flare. Clip 20 also includes a depending, pointed, tang 60 defining a slot 64 similar in shape and size to slot 44 of hook member 42 . A biasing element 66 extends rearwardly of tang 64 on clip 20 , and is spaced by a distance from the underside of finger 50 which corresponds to, or is slightly less than the thickness of housing 24 below access slot 26 thereof. In this way, clip 20 may be held in place against housing 24 by sliding finger 50 into slot 26 below tape 25 , whereupon spring member 66 will bear upon the underside of housing 24 , retaining clip 20 in place with respect to housing 24 . A useful feature of the invention is found in marking implement 70 , which includes a body portion which defines a hook-tab receiving slot 74 for receiving hook member 42 , and a writing or other marking or pivot element 72 . As best seen in FIGS. 2 and 3, a series of ridges or serrations 78 are integrally connected to member 70 within slot 74 , and have a width generally corresponding to the width of slot 44 in hook member 42 . In this way, member 70 can be remissably connected to hook member 42 of measuring tape 25 . The provision of a parality of ridges 78 is intended to facilitate connection of member 70 to tapes having variously sized hook members.
[0039] Referring now to FIG. 4, there is shown a radial alignment tool 90 which, in its preferred form, is comprised of a circular suction cup having a raised central portion 93 having a tang receiving depression 95 therein adapted to receive the pointed end 60 of clip 20 . Tool 90 permits a user to place clip 20 into depression 95 and rotatably pivot clip 20 , and tape measure housing 24 , thereabout and to deploy measuring tape 25 a distance equal to the radius of an arc or circle for purposes of inscribing an arc or circle on a work piece or surface. Measuring tape 25 is deployed a distance corresponding to the arc or circle radius, and inscribing tool 70 is attached to hook end 42 of the tape 25 . Tape 25 is locked in the deployed position by depressing locking mechanism 29 such that the demarcation on tape 25 corresponding to the desired radial distance aligns with measurement indicating extensions 52 , 54 of clip 20 . Tool 90 may employ angular position demarcations which tape 25 can be placed in alignment with to precisely measure angles to be marked on a workpiece.
[0040] [0040]FIGS. 5 and 6 illustrate a modified scribing instrument comprising a body member 70 adapted to be connected to hook end 42 of measuring tape 25 in a manner similar to that described for member 70 . Ridges or serrations 178 are provided within a slot 174 defined by body member 170 . A writing or scribing element 172 is provided, which may be a pencil point or sharp metal point about which hook end 42 may be rotated.
[0041] Another improvement is found in the form of a structure for facilitating sliding movement of scribing element 172 along a work piece or surface and includes a body extension portion 171 which defines a pair of parallel apertures there through 175 through which are disposed a pair of guide pins 173 , each preferably having a rounded or other surface having a low co-efficient of friction. A pair of corresponding compression springs 179 are disposed about guide pins 173 between body extension member 171 and a depression tab 177 . In this way, when scribe element 172 is to be dragged or otherwise translated along a work piece or surface, tab 177 is depressed which will cause the bottom ends of pins 173 to come into contact with said work piece or surface, and consequently be aligned with the bottom most edge of element 172 , to facilitate the translation of element 172 along a work surface. For example, where element 172 is a writing tip, such as a lead pencil, such point might tend to snag or get caught on irregularities in the work piece or surface and low-friction bottom sections of pins 173 will assist in avoiding such tendencies. Releasing tab 177 will cause springs 179 to force tab 177 and pins 173 to raise up to the position shown in FIGS. 5 and 6.
[0042] It is to be understood that the inventions disclosed herein are not limited to the precise constructions shown and described but that changes are contemplated which will readily fall within the spirit of the invention as shall be determined by the scope of the following claims: | This description, together with the objects of the invention and the various features of novelty which characterize the invention are pointed out with particularity in the claims annexed hereto and forming a part of this disclosure. For a better understanding of the invention, its operating advantage is in the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated at least one preferred embodiment of the invention. | 6 |
Research leading to the completion and reduction to practice of the invention was supported in part by Grant No. EEC-9402989 awarded by the National Science Foundation (NSF). The United States Government has certain rights in and to the invention claimed herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a process for the treatment of wastepaper. More particularly, the present invention relates to a process for de-inking wastepaper. Most particularly, the present invention relates to a process for enhanced removal of ink particles and non-ink contaminants from wastepaper.
2. Description of the Prior Art
In modern times, with the ecological concerns about conservation of raw materials and the rapid decline of available landfill space, it has become increasingly desirable to recover and recycle used raw materials. Thus, recovered wastepaper represents a valuable source of raw material for the paper industry. In order for the wastepaper to be regenerated into a viable starting material and to produce a commercially acceptable paper, the wastepaper must be treated to remove any ink particles and non-ink contaminants.
Wastepaper has long served as a source of the raw fiber materials used in paper-making. Traditionally, fiber from wastepaper was utilized only in the production of low grade paper and paperboard products. Today, however, greater utilization of reclaimed fiber has provided incentive for taking steps to upgrade the reclaimed product These steps include treatment to effectively remove ink from waste fibers in order to permit their use in the manufacture of newsprint and high quality papers. Because of its quantity, waste newsprint is a particularly important feedstock to such reclamation processes.
In the course of the conventional paper reclamation process of interest, de-inking procedures include steps for converting the wastepaper to pulp and contacting the pulp with an alkaline aqueous de-inking medium containing a chemical de-inking agent The physical pulping and the alkalinity of the aqueous medium cause the partial removal of ink from the pulp fiber and the de-inking agent completes this removal and produces a suspension and/or dispersion of the ink particles thus removed from the pulp.
The resulting mixture is subsequently treated by flotation or washing to separate the suspended ink from the pulp.
In most conventional de-inking processes, the wash and/or flotation steps are carried out at an alkaline pH, usually 8.5 to 10.5. Conducting the washing or flotation steps at an alkaline pH is convenient because the fluid carried over from the pulping step is alkaline. In addition, many wash de-inking and flotation de-inking processes use fatty acids as surfactants and these fatty acids are capable of functioning as surfactants only when the aqueous medium is sufficiently alkaline to ionize them.
Typically, reclamation is accomplished in two steps:
1. refining the wastepaper, i.e., fiberizing in water in the presence of the chemicals required for detachment of the printing ink particles, and
2. removal of the detached printing ink particles form the fiber suspension.
The second step can be carried out by washing or flotation [ Ullmanns Encyclopaedie der technischen Chemie, 4th Edition, Vol.17, pages 570-571(1979)]. In flotation, which utilizes the difference in wettability between printing inks and paper fibers, air is forced or drawn through the fiber suspension. Small air bubbles attach themselves to the printing ink particles and form a froth at the surface of the water which is removed.
The de-inking of wastepaper is normally carried out at alkaline pH values in the presence of alkali metal hydroxides, alkali metal silicates, oxidative bleaches and surfactants at temperatures in the range of from 30° to 50° C. Anionic and/or non-ionic surfactants, for example, soaps, ethoxylated fatty alcohols and/or ethoxylated alkyl phenols, are mainly used as surfactants [ Wochenblatt fuer Papierfabrikation , Vol. 17, pages 646-649 (1985)].
Many prior art processes are known for de-inking wastepaper, many of which are directed to the development of de-inking agents. In U.S. Pat. No. 4,586,982 (Poppel etal), there is described a process comprising treating the wastepaper in a pulper at an alkaline pH with alkali silicate, an oxidatively active bleaching agent, an acid selected from the group consisting of fatty acids and resinic acids containing more than ten carbon atoms and a dispersing agent wherein the acid and dispersing agent are employed together in an oil-in-water emulsion.
Additional disclosures of de-inking agents are set forth by, for example, Wood et al in U.S. Pat. No. 4,618,400 (thiol ethoxylate compounds); Wood et al in U.S. Pat. No. 4,561,933 (a mixture of C 8 to C 16 alkanols and alcohol ethoxylates); DeCeuster et al in U.S. Pat. No. 4,343,679 (compounds capable of liberating ions with a positive charge equal or greater than 2); Bridle in U.S. Pat. No. 4,483,742 (pine oil and a soap-making fatty acid); and Tefft in U.S. Pat. No. 4,786,364 (a hydrolyzed copolymer of dimethyidiallyl ammonium chloride and acrylamide).
Other prior art processes are directed to improvements in either washing or flotation methods of separating ink particles from wastepaper fibers.
In U.S. Pat. No. 4,548,673, Nanda et al describe a de-inking flotation method comprising the steps of independently introducing air into a fiber stock slurry, mixing the air bubbles and slurry, and separating the ink-laden air bubbles from the fiber slurry, where each of these steps is independently controlled. In U.S. Pat. No. 4,749,473, Shiori et al describe introducing air bubbles into the wastepaper pulp slurry through a number of orifices formed on a peripheral surface of at least one rotatable horizontal cylinder located in the bottom portion of a flotation vessel. In U.S. Pat. No. 4,277,328, Pfalzer et al describe employing an impeller at the bottom of a flotation apparatus for dispersing air into the wastepaper pulp slurry.
U.S. Pat. Nos. 4,162,186 and 4,518,459 disclose additional methods.
Such methods were reasonably satisfactory and adequate a number of years ago when there was no need to de-ink and reclaim wastepaper having little or no quantities of ground wood. Such papers were printed with standard inks which are more readily removed or saponified with chemicals at elevated temperatures.
In recent years, however, methods of de-inking which involve cooking and the use of chemicals in aqueous media have become increasingly unsatisfactory for a number of reasons. Ink formulations have become more and more complex and involve an increasing use of a wide variety of synthetic resins and plasticizers; with each ink having its own special formulation. Also, increasing amounts of synthetic resins and plasticizers are being used in a wide variety of sizings, coatings, plastic binding adhesives, thermoplastic resins and pressure sensitive label adhesives. Furthermore, the use of multi-colored printing and multi-colored advertisements have become increasingly popular in recent years and these involve a wide variety of new ink formulations. Many of the new ink formulations incorporate new pigments, dyesand toners which are difficult to remove by conventional aqueous de-inking chemicals. The former methods of de-inking and reclaiming wastepaper by chemical and cooking techniques are not adapted for, or adequate for, removing the new types of inks and coating resins. Due to high contents of thermoplastic resins, the softening action of heat and chemicals alone makes their separation from the fibers very difficult Additionally, the action of heat and chemicals tends to irreversibly set and more firmly bond some of the present day pigments to the fibers and fix dyes and toners to the fibers through staining.
The challenges that the pulp and paper industry is trying to meet today in the recycling area are to (1) economically produce quality paper meeting the consumer demands and also the legislative demands for the content of recycled paper; and (2) increase the process efficiency in order to make use of recovered paper which currently cannot be processed economically. Currently, most recycling processes are geared only to use high quality recovered paper costing over $150 per ton. Such material is limited in quantity and is in high demand due to the regulations governing the incorporation of certain percentages of recycled fiber in many paper commodities. There exists a need for new recycling processes which are more economical and can handle a wider range of recovered paper. One of the most important steps in recycling the recovered paper is that of de-inking. There also exists a need for methods of de-inking that can handle (1) a wider variety of printed material (newsprint to high quality glossy magazine paper) and (2) a higher pulp density than the conventional processes.
For the above and other reasons, conventional de-inking techniques used in reclaiming processes for wastepaper are no longer efficient or effective for many current needs.
The need for a satisfactory de-inking process has become increasingly important due to greatly expanded utilization of paper and difficulty in disposal of the old papers due to projected lack of landfill sites.
In this regard, to preserve natural resources and minimize environmental problems, the need for developing useful and efficient paper recycling processes becomes of critical importance.
SUMMARY OF THE INVENTION
The present invention solves the need for more efficient processes for recycling cellulosic materials by providing a novel method for de-inking such material.
One embodiment of the invention is a method of de-inking cellulosic fibrous materials comprising:
a. admixing an alkaline reagent selected from the group consisting of ammonium hydroxide and sodium bicarbonate or mixture thereof with hydrogen peroxide and an aqueous suspension of inked cellulosic fibrous material in amounts whereby said ammonium hydroxide and hydrogen peroxide react at the ink particle/cellulosic fiber interfaces to dislodge said ink particles from said cellulosic materials; and
b. removing said dislodged ink particles from said aqueous suspension.
Another embodiment of the invention relates to an improved process for recycling inked cellulosic material which includes the above-described step of de-inking prior to recovery of the cellulosic material.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow chart of a process according to the invention.
FIG. 2 is a graphic depiction of the effect of recycled reagent liquid on pulp yield.
FIG. 3 is a graphic depiction of the effect of recycled reagent liquid on ammonium consumption.
FIG. 4 is a graphic depiction of the effect of recycled reagent liquid on pulp brighteners.
FIG. 5 is a graphic depiction of the effect of flotation time on ash content of the recycled pulp.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is predicated on the discovery that the process of the invention enables the de-inking of a broad spectrum of printed products including newspaper, laser written paper, xerographic paper, rotogravure, heat-set, including coated and uncoated stock and high gloss multi-colored paper, such as magazines. Moreover, the process enables the de-inking of higher pulp densities than typical prior art methods.
As noted above, in conventional de-inking processes, the waste paper is first pulped and the ink particles are removed by using a flotation technique. In this step, the pulp at a solids loading of 1.0-1.25 wt % is treated with various reagents to separate the ink particles from the fiber. The pH of the pulp is adjusted using NaOH. Reagents are then added to emulsify or discharge the ink particles from the fiber interface and a collector is added to float the liberated ink particles. Air is sparged into the pulp stream in order to aid the flotation process. Typical de-inking process chemicals currently used are shown in Table 1.
TABLE 1
DE-INKING PROCESS CHEMICALS
JOHN K. BORCKHARDT, CHEMISTRY AND INDUSTRY, VOL. 19, PAGE 273 (APRIL 1993)
PROCESS STAGE
CHEMICAL
FUNCTION
Pulper
Sodium Hydroxide
Raises pH to 8-10 (typically about 9 to promote fiber swelling and ink
removal, as well as disaggregation of paper into separate fibers (pulp)
Sodium Silicate
Dispersant for detached ink particles, raises pH
Hydrogen Peroxide
Prevents lignin yellowing of pulp promoted by high pH
Complexing Agent
Stabilizes hydrogen peroxide so it does not react with oxidizable dis-
solved metal ions. Usually diethylenepentaminetetraacetic acid (DTPA)
or ethylenediaminetetraacetic acid (EDTA)
Surfactant
Promotes ink detachment from cellulose fiber
Flotation Cell
Fatty Acid
Renders ink particles hydrophobic and stabilizes foam. Used in com-
bination with a soluble calcium salt, usually calcium chloride, to gener-
ate a calcium soap in situ
Synthetic Surfactant
Renders ink particles hydrophobic and stabilizes foam. May be added at
the pulper to promote ink detachment from fiber and carried forward to
the flotation stage
Washing Stage(s)
Synthetic Surfactant
Added in the pulper to promote ink dispersion into small particles that
are readily removed by washing
Bleaching
Hydrogen Peroxide a
Whitens the pulp and increases paper sheet brightness
Sodium Hypochlorite a
Chloride Dioxide a
Sodium
Hydrosulphite b,c
FAS b,d
a Oxidative bleach
b Reductive bleach
c Sodium dithionite
d Formamidine sulphinic acid
In the method of the invention, in the de-inking step, the pulp is treated with a novel reagent scheme which is far less costly than conventional de-inking and flotation reagents. Briefly, to a pulp stream are added a soluble peroxide and a soluble alkaline agent capable of undergoing a reaction with the peroxide to liberate a bubble of gas which functions to float the ink particles in the pulp stream to the surface.
FIG. 1 depicts a flow sheet of a typical de-inking process of the invention. The pulp stream is reagentized with 0.5-1.0 wt. % hydrogen peroxide and 0.1-0.2 wt % ammonia as ammonium hydroxide. The pH in this stage is about 9.5-10.0. These reagents undergo a chemical interaction at the fiber/particle interface and generate a bubble of ammonium gas which dislodges the ink particles and floats them to the top of the vessel. The advantage of this process is that it does not use any expensive collectors as in conventional processes. In addition, there is little need to sparge the system with air as the reagents used generate the bubbles necessary to flotate the ink particles. Additionally, unlike conventional reagent schemes which can handle only 1.0-1.2% solids loading during flotation, the method of the invention can handle up to 2.0% solids loading efficiently. This will nearly double the output of any existing de-inking unit (i.e., reduces the equipment size to half). Additionally, the method of the invention can handle a wider variety of recovered paper than conventional process schemes.
It will be understood by those skilled in the art that any combination of soluble peroxide and soluble alkaline agent which reacts in the pulp stream to generate a bubble of gas may be employed in the practice of the invention. In the case described above (FIG. 1 ), the reagents react according to the following scheme:
2NH 4 OH+H 2 O 2 →NH 3 ↑+2H 2 O+O+NH 4 + +OH −
The liberated ammonium gas operates to flotate the ink particles to the surface.
The combination of a peroxide with an alkali metal bicarbonate may also be used. These would react according to the scheme:
NaHCO 3 +2H 2 O 2 →Na + +OH − +2H 2 O+2O+CO 2 ↑
The liberated carbon dioxide bubbles would then work to float the ink particles to the surface. Since two molecules of nascent oxygen are formed in the system, some will readily combine to form molecular oxygen as well as to bleach the pulp. The molecular oxygen formed would function as an additional flotation agent.
The critical parameters of the method of the invention, therefore, are the use of soluble peroxides and alkaline agents which react under the conditions in the pulp stream to form a gas which bubbles up through the pulp stream and acts to dislodge and float the ink particles present in the pulp stream to the surface.
It is a further feature of the invention that the nascent oxygen released by the reaction between the alkaline agent and the peroxide functions to bleach the pulp and increase its brightness. In addition, the nascent oxygen works to break the oils present in the pulp stream into shorter chain length molecules which function to stabilize the froth in the pulp stream for flotation of the ink particles.
In the cases of combinations of alkaline agents and peroxides which do not react with each other to liberate gas bubbles, the process is much less efficient. For example, where alkali metal hydroxides and hydrogen peroxide are utilized (as in the case of some prior art methods), the reagents react according to the scheme:
NaOH+H 2 O 2 →Na + +OH − +H 2 O+O
Although nascent oxygen is formed which aids in brightening the pulp, no gas bubbles are formed to float the ink particles to the surface of the pulp stream. In this case, a gas such as air must be separately sparged through the system to float the particles which increases the overall cost of the system and decreases the efficiency thereof.
Peroxides other than hydrogen peroxide may also be utilized in the practice of the invention. An alkali metal peroxide would react with ammonium hydroxide according to the following scheme:
2NH 4 OH+Na 2 O 2 →2Na + +2OH − +O+2NH 3 ↑+H 2 O
Again, the liberated ammonia gas bubbles would dislodge and float the ink particles to the surface of the pulp stream.
If desired, adjuvants such as polypropylene glycol may be added to the reaction mixture to enhance flotation and increase pulp brightness.
EXAMPLE
Newspaper is first cut into shreds and homogenized. The paper is then pulped at a solids loading of 2 wt. % in a Hamilton Beach blender for two minutes. Hydrogen peroxide is added during the pulping stage at a dosage of 0.5-1.0 wt. % of dry paper. The reagentized pulp is then transferred to a flotation cell and the pH is adjusted to 9.5-10.0 using ammonium hydroxide. The flotation is performed using a Denver flotation unit for fifteen minutes at 900 rpm. The ink particles are collected in the froth using a manual skimmer. The floated ink particles and the de-inked pulp are then filtered at 0.5 atm vacuum. The filtrate is recycled to subsequent flotation experiments to reduce the reagent consumption by recycling the unreacted reagents. The dewatered pulp is air dried in a convection oven at a temperature of 40° for 4-5 hours. In conventional methods, the dewatered pulp is washed and bleached to increase the brightness of the pulp. However, in this example, post flotation processes to increase the pulp brightness have not been performed as they are invariant with the flotation scheme.
High pulp yields (approximately 90%/o) were achieved in this example. As shown in FIG. 2, the pulp yield is not affected by the recycled water. The ammonia consumption was observed to decrease with each cycle indicating that the ammonia does not completely react and can be partially recycled in the subsequent flotation steps (see FIG. 3 ). The pulp brightness increases with each filtrate recycle indicating that recycling the filtrate is beneficial to the flotation process (see FIG. 4 ). The key measures of de-inking are yield, pulp brightness, ash content and dirt count. The current process has been demonstrated to produce a pulp yield of 90+% which is much higher than the 74-78% yield achieved in the existing industrial processes. A brightness number of 55 is required for the de-inked newsprint pulp to be successfully recycled. An increase in the brightness number of the pulp from 30 to 50 was observed in this example. The required brightness levels can be easily achieved by a post flotation bleaching step which is a common practice in the industry. As shown in FIG. 5, ash content of the recycled pulp can be easily controlled by varying the flotation time. In the current example, the dirt count was significantly reduced from 65,283 to 14,276/m 2 (1,910 to 656 ppm) employing a flotation time of five minutes.
The method of the above example, when repeated utilizing sodium bicarbonate in lieu of ammonium hydroxide, also yields goods results:
Sample
ONP*
ONP*
Average Brightness
49.6
51.6
Original Brightness
55-57
55-57
Paper, %
2
2
H 2 O 2 , %
1
1
NaHCO 3 , %**
1
2
Froth Time, minutes
6
6
*De-inked Old News Print
**Increasing dosage from 1 to 2% increases brightness.
All dosages including hydrogen peroxide are calculated on the basis of percentage of dry weight of paper and refer to the active ingredients. For example, in the case of peroxide, 0.5% indicates weight of pure peroxide to weight of dry paper.
Although the method of the invention has been illustrated with reference to waste newspaper, it will be understood by those skilled in the art that it is equally applicable to the recovery and de-inking of any inked or printed cellulosic material such as, e.g., magazines and the like.
The de-inking process of the invention is a new reagent scheme which is a novel combination of chemicals and reagents already in use in various sections of the pulping process industry. This reagent scheme can be employed in existing de-inking plants without equipment modifications.
The de-inking process of the invention employs a novel procedure to produce bubbles in situ at the fiber/ink interface which dislodges the ink particles from the fiber surface. This is more efficient than conventional de-inking processes which rely only on mechanical methods to dislodge and liberate the ink particles.
Better liberation of ink particles results in higher yield of de-inked pulp. Additionally, this ensures flotation at higher solids loading. The solids loading used in the current process is 2 wt. %., unlike the existing industrial flotation schemes which operate at a solids loading of 1 wt %. Hence, the current process can double the existing throughput of the industry.
The proposed reagent scheme employs fewer reagents than in current industrial processes and, hence, is less complicated. The build-up of any unreacted reagents in the proposed scheme is beneficial and does not play havoc with, e.g., the environment as in existing industrial processes. | A method of de-inking cellulosic fibrous materials comprising:
a. admixing an alkaline reagent selected from the group consisting of ammonium hydroxide and hydrogen peroxide and mixtures thereof with an aqueous suspension of inked cellulosic fibrous material such that they react at the ink particle/cellulosic fiber interfaces to dislodge ink particles from the cellulosic materials; and
b. removing the dislodged ink particles from the aqueous suspension. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The field of invention relates to bow sight apparatus, and more particularly pertains to a new and improved bow sight apparatus wherein the same is directed to the securement of a bow sight structure relative to an associated archery bow.
2. Description of the Prior Art
The use of sight structure mounted relative to an associated archery bow is present in the prior art in a variety of configurations, such as indicated in the U.S. Pat. Nos. 5,050,576; 4,967,478; 4,894,921; and 4,999,919.
The instant invention attempts to overcome deficiencies of the prior art by providing for a bow sight structure arranged for ease of adjustment and accommodation of an archery quiver utilizing a compact rigid organization and in this respect, the present invention substantially fulfills this need.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in the known types of bow sight apparatus now present in the prior art, the present invention provides a bow sight apparatus wherein the same provides for a unitary mounting plate secured orthogonally relative to an archery bow adjacent its handle for mounting forward and rear sights forwardly and rearwardly of the associated archery bow. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new and improved bow sight apparatus which has all the advantages of the prior art bow sight apparatus and none of the disadvantages.
To attain this, the present invention provides a bow sight member including a mounting plate secured to a bow in an orthogonal relationship, with the mounting plate including an L-shaped front sight support member projecting forwardly of the bow, with an L-shaped rear sight member positioned rearwardly of the bow, wherein each sight member includes a mounting plate arranged in a coplanar relationship to slidably secure respective front and rear sight plates thereon, with the front and rear sight plates respectively mounting respective front and rear sights.
My invention resides not in any one of these features per se, but rather in the particular combination of all of them herein disclosed and claimed and it is distinguished from the prior art in this particular combination of all of its structures for the functions specified.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. Those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
It is therefore an object of the present invention to provide a new and improved bow sight apparatus which has all the advantages of the prior art bow sight apparatus and none of the disadvantages.
It is another object of the present invention to provide a new and improved bow sight apparatus which may be easily and efficiently manufactured and marketed.
It is a further object of the present invention to provide a new and improved bow sight apparatus which is of a durable and reliable construction.
An even further object of the present invention is to provide a new and improved bow sight apparatus which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible of low prices of sale to the consuming public, thereby making such bow sight apparatus economically available to the buying public.
Still yet another object of the present invention is to provide a new and improved bow sight apparatus which provides in the apparatuses and methods of the prior art some of the advantages thereof, while simultaneously overcoming some of the disadvantages normally associated therewith.
These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:
FIG. 1 is an orthographic view of the mounting plate structure of the invention.
FIG. 2 is an orthographic view, taken along the lines 2--2 of FIG. 1 in the direction indicated by the arrows.
FIG. 3 is an orthographic view, taken along the lines 3--3 of FIG. 1 in the direction indicated by the arrows.
FIG. 4 is an orthographic top view of the rear sight plate structure of the invention.
FIG. 5 is an orthographic side view of the rear sight plate structure of the invention.
FIG. 6 is an orthographic bottom view of the sight support member utilized by the invention.
FIG. 7 is an orthographic end view of the sight support member.
FIG. 8 is an orthographic view, taken along the lines 8--8 of FIG. 7 in the direction indicated by the arrows.
FIG. 9 is an orthographic top view of the front sight plate structure.
FIG. 10 is an orthographic side view of the front sight plate structure.
FIG. 11 is an isometric illustration of the invention relative to an associated archery bow illustrated in isometric and exploded view.
FIG. 12 is an orthographic exploded view a modified rear sight member utilized by the invention.
FIG. 13 is an isometric illustration of a modified rear sight member post structure.
FIG. 14 is an isometric illustration of a modified front sight member post structure.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawings, and in particular to FIGS. 1 to 14 thereof, a new and improved bow sight apparatus embodying the principles and concepts of the present invention and generally designated by the reference numeral 10 will be described.
More specifically, the bow sight apparatus 10 of the instant invention essentially comprises a mounting plate 11 having planar side walls, including a first end 12 spaced from a second end 13, with a top side 14 spaced from a bottom side 15. First and second smooth mounting bores 16 and 17 defining a first row are directed through the mounting plate medially of the first and second ends 12 and 13. Third and fourth internally threaded mounting bores 18 and 19 defining a second row of bores are positioned between the first row and the first end 12. Fifth and sixth internally threaded mounting bores 20 and 21 defining a third row of bores are directed through the mounting plate between the first row and the second end, wherein the first, second and third row of mounting bores are arranged in a parallel relationship relative to one another. The first row of mounting bores are arranged to receive fasteners 22 to secure the mounting plate 11 relative to a bow "B", as illustrated in FIG. 11. The second row of mounting bores are internally threaded and arranged to receive fastening of a quiver for use by a left-handed shooter, wherein the third row of mounting bores 20 and 21 are arranged to receive an arrow quiver for a right-handed shooter relative to the bow "B". The arrow quiver structure is not shown but is of conventional construction, wherein the second and third rows of bores are available for mounting of such structure. A fourth row of bores of a seventh and eighth internally threaded bore 23 and 24 are positioned adjacent the first end 12 and are orthogonally oriented relative to the first, second, and third row of bores. Ninth and tenth internally threaded bores 25 and 26 adjacent the second end 13 are colinear with the fourth row, as illustrated.
An L-shaped front sight support member 27 is provided, having a first plate 28 orthogonally mounted to a second plate 30. The first plate 28 includes a plurality of parallel slots directed therethrough, with the slots 29 arranged for alignment with one of the seventh and eighth bores 23 and 24. A plurality of second plate threaded bores 30a are directed through the second plate to receive a front sight plate 31 thereon, wherein the front sight plate includes a plurality of parallel front sight plate slots 32 orthogonally oriented relative to the first plate 28, and to include front sight fasteners 33 directed through the front sight plate slot 32 into the second plate threaded bores 30a. A front sight post 34 is mounted orthogonally to the front sight plate 31 for alignment with a rear sight, to be discussed in more detail below. An alternative front sight, as indicated in FIG. 14, has a modified post 34a.
An L-shaped rear sight support member 35 is provided of substantially identical construction to the front sight support member 27. A third plate 36 is orthogonally mounted integrally to a fourth plate 38, wherein the third plate 36 includes a plurality of parallel third plate slots 37, with the third plate slots 37 arranged to receive one of the ninth and tenth internally threaded bores 25 and 26 respectively to include rear fasteners 43 through the slots 37 into the bores 25 and 26. Similarly, front fasteners 42 are directed through the slots 29 into the associated bores 23 and 24. The fourth plate 38 includes a plurality of fourth plate bores 38a, with a rear sight plate 39 provided, having rear sight plate slots 40 in a parallel relationship relative to one another and orthogonally oriented relative to the third plate 36, as well as to the mounting plate 11. Rear sight plate fasteners 41 directed through the slots 40 are received within the bores 38a. In this manner, the front and rear sight plates are arranged for adjusting orientation orthogonally relative to the mounting plate 11.
The FIG. 12 indicates the use of a modified rear sight plate 45 having in addition to the parallel rear sight plate slots 40, a plurality of rear sight plate threaded bores 45a. A sighting block is provided, having sight block fasteners 56 directed therethrough received within the rear sight plate threaded bores 45a, as illustrated. The sighting block 46 includes a groove 47 oriented between parallel flanges 48 projecting from a top wall of the sighting block 46. The flanges 48 are orthogonally oriented relative to the rear sight plate 45. Further, an axle 49 is directed through the flanges 48, with the axle further directed through an L-shaped sight member 50, with the L-shaped sight member 50 receiving the axle 49 therethrough at an intersection of a first and second sight blade 51 and 52 of the L-shaped sight 50. The first sight blade 51 includes first sight blade first and second bores 53 and 54 oriented parallel relative to one another through the first sight blade, with the second sight blade including a second sight blade first bore 55. The first sight blade bores 53 and 54 are orthogonally oriented relative to the second sight plate first bore 55. In this manner, a plunger 57 positioned below the L-shaped sight 50 arranged to intersect the L-shaped sight 50 in adjacency to the axle and below the axle 49 imposes upon the L-shaped sight 50 at the intersection of the first and second sight blades 51 and 52 to maintain the L-shaped sight in an orientation to position selectively the first or second sight blade 51 and 52 orthogonally relative to the top wall of the sighting block 46 within the groove 47. The modified rear sight structure, as indicated in FIG. 12, is utilized to provide for variously diameter peep sights as the bores 53, 54, and 55 are of varying diameters to provide for varying fields of view in a peep sight usage.
As to the manner of usage and operation of the instant invention, the same should be apparent from the above disclosure, and accordingly no further discussion relative to the manner of usage and operation of the instant invention shall be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A bow sight member includes a mounting plate secured to a bow in an orthogonal relationship, with the mounting plate including an L-shaped front sight support member projecting forwardly of the bow, with an L-shaped rear sight member positioned rearwardly of the bow, wherein each sight member includes a mounting plate arranged in a coplanar relationship to slidably secure respective front and rear sight plates thereon, with the front and rear sight plates respectively mounting respective front and rear sights. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority to U.S. provisional application Ser. No. 61/983,854 filed on Apr. 24, 2014, the disclosure of which is incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to high-temperature furnace operation in which heat is provided to a charge, such as glassmaking materials, by combustion of fuel and an oxygen-containing stream having an oxygen content higher than that of air.
BACKGROUND OF THE INVENTION
[0003] Many industrial operations require heating materials to a high temperature in a furnace or equivalent apparatus. The requisite high temperature can be provided by combusting fuel with air, at a rate sufficient to provide heat of combustion that heats the materials. More recently, in operations termed “oxy-fuel”, the air as a source of oxygen is replaced by a gaseous feed containing more than 90 vol. % oxygen. Combustion with oxygen having such a high purity provides numerous advantages including attaining high temperatures, less diversion of heat to the non-reactive components of the feed air, and a lessened tendency to form nitrogen oxides.
[0004] One of the drawbacks of oxy-fuel melting is the higher operating cost. Using a gaseous feed stream with less than 90 vol. % oxygen as the oxidant, such as diluting a high purity oxygen from liquid supply stream with air, can reduce the unit cost of contained oxygen. However, using low purity oxygen reduces the energy efficiency of the oxy-fuel system, increasing the fuel consumption and, in turn, increasing the oxygen consumption, relative to the base case. Furthermore, if not properly managed, the resulting higher nitrogen content in the oxidant coupled with the high temperature flame can adversely impact NOx emissions from the process.
[0005] However, the present invention recognizes that when coupled with a heat recovery device such as a regenerator, even more advantages such as improved energy efficiency, reduced emissions, and improved furnace operation can be realized with operation using oxidant in which the oxygen content is less than what is used in oxy-fuel combustion.
BRIEF SUMMARY OF THE INVENTION
[0006] One aspect of the invention is a method of operating a furnace which contains a charge to heat the charge, comprising:
[0007] (A) providing gaseous oxidant comprising 60 vol. % to 85 vol. % oxygen;
[0008] (B) passing the gaseous oxidant through a heated regenerator and out of an oxidant port into a furnace, to heat the oxidant in the regenerator so that it emerges from the oxidant port at a temperature of 500° C. to 1400° C., and to thereby cool said regenerator; and feeding gaseous fuel into said furnace through two or more fuel ports and combusting the fuel in the furnace with heated oxidant emerging from said oxidant port to produce gaseous hot products of said combustion which heat the charge;
[0009] (C) discontinuing the flow of oxidant through the regenerator into the furnace, and passing said combustion products into said oxidant port and through and out of said cooled regenerator to heat said regenerator, wherein the temperature of the combustion products that pass out of said regenerator is at least 500° C.; and
[0010] (D) alternating steps (B) and (C),
[0011] wherein said oxidant port and said fuel ports are located above the top surface of said charge in said furnace;
[0012] wherein at least one of said fuel ports is located on each side of a vertical line passing through the center of said oxidant port and said fuel ports are located 10 to 60 fuel port diameters from said oxidant port; and
[0013] wherein the fuel that is combusted with oxidant from a given oxidant port is fed into the furnace from a fuel port that is on one side of said line at a velocity of 40 to 350 m/sec and from a fuel port and the oxidant is fed into the furnace from the oxidant port at a velocity of 2 to 20 m/sec, wherein the fuel fed from said fuel ports entrains gaseous combustion products in said furnace before combusting with the high temperature oxidant stream.
[0014] By controlling the fuel velocities of the fuel ports, through the use of independent adjustable flow controllers, the flame shape and characteristics can be varied and the energy release profile can be controlled inside the furnace and close to the refractory side walls. This flexibility avoids overheating of the furnace refractory walls or the charge material by the high temperature flame.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a schematic top view of an embodiment of a furnace and associated equipment with which the present invention can be practiced.
[0016] FIG. 2 is a schematic top view of another embodiment of a furnace and associated equipment with which the present invention can be practiced.
[0017] FIG. 3 is a front plan view of an interior wall of the furnace shown in FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
[0018] Referring to FIGS. 1 and 2 , furnace 1 is a glassmelting furnace or any other furnace in which a charge is exposed to very high temperatures provided by combustion within the furnace. Examples of other furnaces with which the present invention may be practiced include incinerators, and furnaces for melting nonferrous such as copper or aluminum, and furnaces for heating or reheating iron and steel objects such as bars, rods, and ingots.
[0019] In a glassmelting furnace, glassmaking ingredients such as soda ash, niter, silica, sodium silicate, and/or pieces of broken glass (“cullet”) are fed into the furnace where they are melted together to form a bath 6 of molten glass. Furnace 1 includes side walls 2 A and 2 B, end wall 3 , and front wall 4 which includes opening 5 through which molten glass can flow out of furnace 1 .
[0020] Furnace 1 can be provided with a plurality of regenerators 11 in side walls 2 A and 2 B. FIG. 1 illustrates an embodiment of such an arrangement, with two pairs of regenerators in the side walls. Furnace 1 can be provided with a plurality of regenerators in the end wall 3 . FIG. 2 illustrates an embodiment of such an arrangement, with one pair of regenerators 12 in end wall 3 .
[0021] Gaseous oxidant stream 15 is fed into regenerators 11 and 12 . Oxidant stream 15 has an oxygen content of 60 vol. % to 85 vol. %, preferably 65 vol. % to 80 vol. %, and more preferably 65 vol. % to 75 vol. %.
[0022] The oxidant stream 15 having the desired oxygen content can be provided in any of several ways. It can be obtained from a separate commercial source already at the desired oxygen content. It can be obtained by combining air and a higher-content stream whose oxygen content is higher than the desired final oxygen content for stream 15 ; in this case the higher-content stream can be obtained from a separate commercial source, or can be produced by an on-site commercial air separation unit such as those described herein which produces a product stream having an oxygen content higher than 60 vol. % and more preferably higher than 85 vol. %.
[0023] Most preferably, oxidant stream 15 having the desired oxygen content of 60 vol. % to 85 vol. % is produced from an on-site air separation unit 13 .
[0024] Air separation unit 13 is apparatus, preferably a vacuum pressure swing adsorption (VPSA) or pressure swing adsorption (PSA) or temperature swing adsorption (TSA) apparatus, which treats a feed stream 14 to produce an oxidant stream 15 . Feed stream 14 , which is preferably air, has an oxygen content lower than 60 vol. %. Cyclic adsorption processes are well known and are typically used to separate a more absorbable component gas from a less absorbable component gas. Examples include pressure swing adsorption (PSA) or vacuum pressure swing adsorption (VPSA) processes which use a low pressure or a vacuum and a purge gas to regenerate the sorbent, and temperature swing adsorption (TSA) processes which use a thermal driving force such as a heated purge gas to desorb the impurities. Such processes are generally used to separate oxygen or nitrogen from air, other impurities like hydrocarbons and/or water vapor from feed air gases, hydrogen from carbon monoxide, carbon oxides from other gas mixtures, and the like. These processes are also used to remove impurities such as water vapor and hydrocarbons from air prior to cryogenic air separation. Any cyclic adsorption system for separating or purifying gas components can be used in unit 13 .
[0025] For illustrative purposes, a typical VPSA process for separating oxygen from air is described herein although the present invention can be employed with other cyclic adsorption processes using centrifugal compressors and is not intended to be limited to this process. The typical cyclic VPSA process is one wherein an adsorber bed undergoes the following stages:
[0026] (A) The adsorber bed, which comprises adsorbent that preferentially adsorbs the gas or gases to be removed (such as nitrogen when the feed gas is air) is pressurized to a desired pressure wherein the gas or gases to be removed will be readily adsorbed by the adsorbent as the feed air is passed across the bed;
[0027] (B) Product gas rich in oxygen is produced and recovered as the nitrogen in the feed air is adsorbed;
[0028] (C) The bed containing the adsorbent is evacuated to a low pressure (typically under vacuum) wherein the adsorbed nitrogen is desorbed from the adsorbent in the adsorber bed; and, preferably,
[0029] (D) A purge gas is passed through the bed to remove any remaining nitrogen.
[0030] The cycle time is understood by the skilled person to mean the amount of time needed to complete one cycle; e.g. the process steps in order and then return to the starting condition.
[0031] Suitable adsorbents are readily familiar to those who practice in this technical field, and can be identified in the open literature.
[0032] Some adsorption processes will have more steps or multiple beds and often use one or more blowers for each of the pressurization and depressurization steps. If the VPSA plant contains two or more adsorber vessels, each vessel undergoes the above steps; however, the two vessels are operated out of phase so that while one vessel is producing product the other is being regenerated. Also, in a two bed process two blowers are typically used wherein one is dedicated to feeding gas to the adsorber vessels while the other dedicated to evacuating the adsorber vessels.
[0033] Regardless of whether a single vessel, two vessels, or even more vessels are used, the pressures and flows within the process change quickly as the process cycles from adsorption to desorption. Generally, the pressure of a vessel will change from a low pressure condition of at or below atmospheric, preferably below atmospheric, such as about 6 to 8 psia, to a high pressure condition of above atmospheric, such as about 19 to 24 psia, in a rapid periodic cycle time, such as less than one minute. Some adsorption processes will require even wider spans of pressures and/or vacuums in similar rapid cycle times.
[0034] There is ample published technical literature in the field of adsorption processes for producing oxidant streams of the composition described herein, including patents such as U.S. Pat. No. 4,643,743 and patents citing or cited in that patent.
[0035] The desired oxygen content of oxidant stream 15 that is produced by unit 13 is achieved by operating unit 13 in an increased oxygen product/feed air ratio mode. Operating in this manner increases the oxygen recovery and the amount of contained oxygen produced by the air separation unit, while the oxygen concentration in the product oxidant stream and the power requirement are reduced, relative to conventional mode of operation in which the air separation units are designed to produce oxidant product having an oxygen purity of 90% or more.
[0036] Oxidant stream 15 that is produced by unit 13 is typically at a pressure of 19.7 to 64.7 psia and is typically at a temperature of below ambient to 200° C. Oxidant stream 15 is conveyed by suitable piping to each regenerator.
[0037] Each regenerator is configured so that oxidant 15 can be fed into the regenerator outside furnace 1 , and so that oxidant can pass through the regenerator and emerge out of oxidant port 20 (seen in FIG. 3 ) as heated oxidant 16 into furnace 1 . Each regenerator is also configured so that flue gas, comprising gaseous products of combustion in furnace 1 , can pass into port 20 and through the regenerator and can emerge from the regenerator as flue gas stream 19 . Each regenerator is made of material such as ceramic refractory material, and may contain objects such as balls or checkerwork made of ceramic refractory material, wherein the material can be heated by hot flue gas that passes through the regenerator, and the material can heat gas such as oxidant 15 that passes through the regenerator at a temperature lower than the temperature of the regenerator material.
[0038] Each regenerator includes suitable valves and controls for the valves, to enable the operator to control whether the flow of gas through the regenerator is the oxidant 15 flowing from outside furnace 1 into furnace 1 , or is flue gas 19 from inside furnace 1 out through the regenerator to the atmosphere, to a collector, to another heat exchanger where the heat of the flue gas can be recovered, or to another industrial process.
[0039] As shown in FIG. 1 , at least two streams 17 and 18 are associated with each stream of heated oxidant 16 that emerges from a regenerator into furnace 1 . Streams 17 and 18 comprise fuel that is combusted in furnace 1 with heated oxidant 16 .
[0040] Referring to FIG. 3 , oxidant port 20 is the opening from which heated oxidant emerges from the regenerator into the interior of furnace 1 . Also, as mentioned, flue gas 19 leaves the interior of furnace 1 into the regenerator through oxidant port 20 . As also seen in FIG. 3 , fuel ports 21 and 22 are located on opposite sides of an imaginary vertical line L that passes through the center of oxidant port 20 . The distance of each fuel port from the center of the associated oxidant port 20 is 10 to 60 fuel port diameters, preferably 30 to 50 fuel port diameters. Fuel stream 17 is fed into furnace 1 through fuel port 21 , and fuel stream 18 is fed into furnace 1 through fuel port 22 . Fuel streams 17 and 18 are fed from outside furnace 1 and do not pass through a regenerator. Suitable fuels include any gaseous hydrocarbon, such as natural gas, methane, propane, and the like.
[0041] Fuel ports 21 and 22 are oriented so that their axes are horizontal or form an angle that is up to 10 degrees below horizontal, preferably up to 6 degrees below horizontal and up to 10 degrees, preferably up to 6 degrees toward the imaginary vertical line L that passes through the center of oxidant port 20 . This feature helps protect the refractory sidewalls and crown of the furnace from excessive heat. For the end wall configuration, FIG. 2 , oxidant port 20 in the end wall is oriented so that its axis forms an angle that is up to 10 degrees toward the center of the furnace, preferably up to 6 degrees toward the center of the furnace. This feature helps protect the refractory side wall of the furnace from excessive heat.
[0042] The oxidant port 20 is elevated from the surface 6 of the molten material so that the combustion zone and the flame do not directly impinge on the surface of the molten material, and the heated oxidant circulates within the furnace to prevent buildup of volatile alkali species in close proximity to the crown of the furnace (i.e. the interior surface of the top of the furnace). By reducing the amount of alkali volatilization in the furnace and concentration close to the crown, this feature allows standard refractory materials such as those used in air-fuel furnaces to be used in the entire furnace of the present invention, reducing the cost of furnace construction. Preferably, the oxidant port 20 is positioned so that the bottom of the port opening is in the range of 0.76 to 1.52 m (30 to 60 inches) above the molten glass material. More preferably the oxidant port 20 is positioned so that the bottom of the port opening is in the range of 0.89 to 1.27 m (35 to 50 inches) above the molten glass material. Doing so reduces the rate of alkali volatilization from the molten glass and the concentration of volatile species close to the furnace crown.
[0043] Fuel ports 21 and 22 are elevated from the surface 6 of the molten material so as to entrain furnace gases and to reduce the peak temperature of the high temperature oxidant-fuel flame. Furthermore, the elevation ensures that the combustion zone and the flame do not directly impinge on the surface of the molten material and the resulting velocity magnitude of the flame on the surface of the glass material is reduced. Preferably, the fuel ports 21 and 22 are positioned at least 0.7 m (27.6 inches) above the molten glass material. More preferably the fuel ports 21 and 22 are positioned at least 0.9 m (35.5 inches) above the molten glass material. Doing so reduces the resulting velocity magnitude of the flame on the surface of the glass material, reduces the rate of alkali volatilization from the surface of the molten glass, and the concentration of volatile species close to the furnace crown.
[0044] In operation, each regenerator alternates between a combustion stage in which oxidant passes through the regenerator and is combusted in furnace 1 with fuel, and an exhaust stage in which hot gaseous combustion products pass from furnace 1 through the regenerator and out as stream 19 .
[0045] In the combustion stage, oxidant 15 is fed into and through a regenerator which has already been heated as described herein. The oxidant emerges from oxidant port 20 into furnace 1 as heated oxidant 16 . The temperature of heated oxidant stream 16 is 500° C. to 1400° C., preferably 800° C. to 1350° C., and more preferably 1100° C. to 1350° C. The temperature of the heated oxidant can be achieved by appropriate adjustment of the temperature to which the regenerator is heated, the flow rate of the oxidant 15 into and through the regenerator, and the length of time that the oxidant 15 is exposed to heat within the regenerator. The velocity of the oxidant emerging from oxidant port 20 is 2 to 20 meters per second (m/sec).
[0046] Fuel is fed from fuel ports 21 and 22 into furnace 1 and is combusted with the heated oxidant 16 . Additional fuel ports can be used in the furnace of this invention to inject natural gas into strategic locations within the furnace to tailor the furnace temperature profile. The stoichiometric ratio of fuel to oxidant is preferably in the range to promote complete combustion of the fuel and result in preferably 1% to 2.5% excess oxygen in the flue gas. The fuel from fuel port 21 and 22 are fed at a velocity of 40 to 350 m/sec, preferably 60 to 250 m/sec. Ports 21 and 22 may be operated at different velocities. The differing velocities at the two fuel ports controls the heat release profile of the flame in the furnace. High fuel velocities can be used for the fuel ports removed from the furnace sidewalls and aids in entraining the furnace atmosphere into the fuel before it combusts with the preheated oxidant stream, lowering the peak flame temperature in the furnace, the amount of nitrogen oxides that are formed, and prevents overheating of the refractory walls by the high flame temperatures formed by the preheated oxidant-fuel mixture. Low fuel velocities can be used for fuel port close to the furnace sidewalls, reducing the rate of mixing of the fuel and the high temperature oxidant stream, reducing the rate of heat release and peak flame temperature close to the furnace sidewalls.
[0047] Oxidant and fuel are introduced under pressure through the regenerator port and fuel nozzles, respectively, and directed toward the combustion zone. The velocity of the oxidant and the velocities of the fuel streams are provided by the dimensions of the fuel nozzles and regenerator ports, and the oxidant and fuel streams feed rates, which may vary depending on the type of process, the amount of material being processed, and the type of fuel being used. The fuel ports 21 and 22 will preferably have an internal area in the range of 0.0005 to 0.0127 m 2 (1 to 5 inches interior diameter) and the oxidant port 20 will preferably have an internal area in the range of 0.5 to 4 m 2 .
[0048] The flow of oxidant through the regenerator, which cools the regenerator because of the heat transfer to the oxidant, is continued up until the regenerators bricks are sufficiently cooled, after which the operation of the furnace is reversed. The point at which the flows are reversed is determined based on factors familiar to those who practice in this field; factors include the desire to optimize the recovery of waste heat from the furnace flue gas and the preheat temperature of the oxidant stream entering the furnace.
[0049] Then, the flow of oxidant through the regenerator is shut off, and the flow of flue gas from within furnace 1 into oxidant port 20 and through the regenerator and out of the regenerator as stream 19 begins. The flue gas heats the regenerator, to provide heat which eventually heats the next flow of oxidant that passes through the regenerator. In the embodiment of FIG. 1 , oxidant and fuel had been flowing into furnace 1 from the regenerators at the top of the figure with flue gas exiting through (and heating) the regenerators at the bottom of the figure.
[0050] The temperature of the flue gas (i.e. hot gaseous combustion products) leaving furnace 1 is typically at least 1400° C. and is typically in the range of 1100° C. to 1550° C. Preferably, the temperature of the flue gas exiting the regenerator is reduced by at least 300° C. and is at least 500° C. The high temperature of the flue gas that leaves the regenerator helps to lessen or prevent deposits from forming on the surfaces within the regenerator. Such deposits could include volatilized components from the molten charge within furnace 1 , or products formed by interaction between such volatilized components and products of the combustion of the fuel and the oxidant. The high temperature of the flue gas helps ensure that the volatilized byproducts remain volatile all the way through and out of the regenerator. This feature reduces the rate of fouling and plugging of the heat recovery device and prolongs the service life of the regenerators and the furnace operation. Preferably all of the gaseous combustion products produced by combustion of the fuel and the oxidant leave the interior of furnace 1 through one or more of the regenerators.
[0051] The invention provides numerous advantages.
[0052] One advantage is that the heating of the charge is achieved at an improved overall energy efficiency, even though the oxidant used in this invention contains more nitrogen than would be present in a higher-purity oxygen stream typically used in oxy-fuel combustion, reducing the amount of fuel and oxidant required for the process.
[0053] The invention also lessens NOx formation in the furnace, even though the oxidant used in this invention contains more nitrogen than would be present in a higher-purity oxygen stream typically used in oxy-fuel combustion.
[0054] The invention also lessens alkali volatilization, and concentration in close proximity to the furnace crown, compared to conventional oxyfuel furnace operation.
[0055] The invention also lessens the heat recovery device fouling and plugging, extending the service life of the regenerators. | Disclosed is a method of operating a furnace containing a charge to heat the charge, comprising wherein gaseous oxidant comprising 60 vol. % to 85 vol. % oxygen is passed through a heated regenerator and into the furnace, so that the oxidant is heated to emerge from an oxidant port at a temperature of 500° C. to 1400° C., and gaseous fuel is fed into said furnace through two or more fuel ports; and the heated oxidant and fuel are combusted in the furnace to produce gaseous hot products of said combustion which heat the charge; and then the flow of oxidant through the regenerator into the furnace is discontinued, and said combustion products are passed into said oxidant port and through and out of said cooled regenerator to heat said regenerator, wherein the temperature of the combustion products that pass out of said regenerator is at least 500° C.; under dimensional and operational conditions which attain functional and economic advantages. | 8 |
FIELD OF THE INVENTION
The present invention relates generally to equipment used for ground boring; more specifically to a method and apparatus associated with manipulating drill rod used in drilling; and more particularly still to a method and apparatus for indexing drill rod loading mechanisms between columns in a drill rod magazine mounted on a horizontal directional drilling machine.
BACKGROUND OF THE INVENTION
Horizontal directional drilling, commonly referred to as HDD, is a process used in a number of applications such as installing utilities underground. The HDD process, regardless of the application, includes a pilot hole-boring step. In this step a bore hole is created that extends underground—generally horizontal or parallel to the surface of the earth—starting at a launch point and ending at a termination point.
The bore hole is created by positioning a boring machine to rotate and push a drill string through the ground. A drill bit is attached to the leading end of the drill string. The drill string is created by connecting individual drill rods together end-to-end from a supply of drill rods stored on the boring machine. The connection between the rods is made up, and subsequently broken in a later step, by the boring machine. A typical boring machine includes a gearbox that connects to the drill string, a drill rod storage magazine, and a rod loading mechanism. The rod loading mechanism moves the individual drill rods from the storage magazine into alignment with the drill string and the gearbox where the individual drill rod is connected to and made a part of the drill string.
Rod loading mechanisms typically include a rod transfer mechanism that moves the rod from the storage magazine and positions the rod with one end in alignment with the drill string and the other end in alignment with the gearbox. Typically, when the drill rod is not being used as part of the drill string, it is stored in a plurality of columns within the storage magazine. In many of these systems, the drill rod is removed sequentially from the first column of the storage magazine proximal to the drill string. After the first, proximal column is emptied, then drill rod is taken from the next adjacent column. Depending on the number of drill rods required for the application, the drill rod is removed column by column until the most distal column is emptied. When the drill string is later broken down, the reverse procedure is utilized, whereby the most distal column is filled first, with next closer adjacent column filled next, and continuing until the proximal column is filled.
The above method is especially used with rod transfer mechanisms that employ a single rod blocking member, with a rod receiving pocket, or grip, located proximal the drill string. The rod receiving pocket may be located physically adjacent the rod blocking member or may be part of the same structure. In either event, however, if the rod receiving pocket is indexed past a column that is not yet emptied, then the drill rod from that column is unintentionally released into the drill string area. Since the drill rod is generally both long and heavy, drilling must cease until the drill rod is untangled and removed from the drill string area. This creates an inefficient and aggravating situation.
In order to insure that the rod transfer mechanism is properly indexed to the appropriate column, mechanical stops have been employed in the past. However, to set the stops to the correct index position, the operator needed to stop drilling, leave the operator position, move to the magazine area, and then manually set the stop. Alternatively, a second person needed to set the position. In either instance the process was inefficient. Therefore, there is a need in the art for a method and apparatus for efficiently and correctly setting the index position for the appropriate column of a drill rod magazine of an HDD machine from the operator position. The present invention overcomes the shortcomings of the prior art and addresses these needs in the art.
SUMMARY OF THE INVENTION
The present invention generally relates to a method and apparatus for properly indexing the rod transfer mechanism of an HDD machine to position the rod receiving pocket under the appropriate column of the drill rod storage magazine. Mechanical stops are utilized on the rod transfer mechanism, with the stops being offset from one another. The stops engage a moveable block which is moved by the operator using a block position selector device.
As the selector device is actuated, the block moves between stop positions. For each selector device position, the block is aligned with one of the stops. Further, the stops are arranged such that each stop corresponds to a respective column of the magazine. Accordingly, the rod transfer mechanism moves transversely away from the longitudinal axis of the drill string until the selected stop engages the block. In this manner, the rod receiving pocket is located beneath the appropriate column, and the column is emptied of drill rod before moving the block to the next column position.
The block position selector device is preferably located at the HDD machine operator's station. The selector device enables the operator to select the appropriate column of the magazine. This is accomplished functionally by the selector device arranged and configured to physically move the block in discrete increments to the appropriate positions corresponding to the offset stops. In the preferred embodiment, a cable slidably received within a jacket is employed between the position selector and the block to move the block.
One aspect of the invention relates to the ergonomic and positive manner in which the selector device operates. More specifically, in one preferred embodiment, the stops are offset vertically and the moveable block is spring biased toward its upward most position. This requires a force to be applied to a pivoting lever of the selector device in order to move the lever (and, correspondingly, the block) to a position other than the first column. Additionally, a first handle is included on the distal end of the lever (e.g., the end away from the pivot point of the lever) and a biased latch is attached to the lever. The biased latch includes a pin biased into engagement with one of a plurality of pockets visible within a selector window. The location of the pockets in the window provide a sure visual representation to the operator of the column from which the drill rod will be selected. Further, because the lever includes the latch, the lever cannot inadvertently move (and thus the block cannot move) to an unwanted column.
In operation, the operator selects the appropriate column by lifting the spring biased latch on the lever (e.g., by moving a second handle attached to the biasing latch toward the first handle at the distal end of the lever). This lifts the pin out of the current engagement pocket such that the operator can then move the lever to the desired column. Releasing the spring biased latch then lowers the pin into the newly selected pocket. As the lever is moved, the block is raised (or lowered depending on the direction of movement of the lever) so as to engage a different stop. This in turn selects the column in the magazine.
Therefore, according to one aspect of the invention, there is provided a drill rod handling system, comprising: a drill rod storage magazine, wherein the drill rod is stored in a plurality of columns; a rod transfer mechanism, the rod transfer mechanism including a plurality of stops, the stops being offset from one another and each of which are positioned such that the rod transfer mechanism unloads drill rod from one of the columns; and a moveable block which selectively engages one of the stops, wherein the moveable block is positioned into alignment with a stop to select drill rod from a desired column.
According to further aspects in accordance with the foregoing paragraph, there is provided: a mechanical linkage connected to the moveable block, the mechanical linkage moving the moveable block based on a selected position; a plurality of selection positions corresponding to the columns; and a selection lever and a biased latch, the biased latch engaging a selection position, whereby the mechanical linkage cannot move between selection positions until the biased latch activated.
According to another aspect of the invention, there is provided a horizontal directional drilling machine, comprising: a drill rod storage magazine having a plurality of generally vertical columns; a boring assembly defining a drill string axis comprising a rack frame with an upper end and a lower end, a gearbox configured to travel along the rack frame from the upper end to the lower end, and a vise assembly a the lower end; a drill rod transfer mechanism configured to move transversely relative to the drill string axis to receive drill pipe from the storage magazine; an operator station; a plurality of stops mounted on the drill transfer mechanism, the plurality of stops being offset from one another and each of which are positioned such that the rod transfer mechanism unloads drill rod from one of the vertical columns; and a moveable block which selectively engages one of the stops, wherein the moveable block is positioned into alignment with a stop to select drill rod from a desired vertical column.
According to yet another aspect of the invention, there is provided a method for selecting a desired column of a drill rod magazine having a plurality of columns, the magazine of the type utilized on a horizontal directional drilling machine where a drill rod transfer mechanism moves the drill rod from the desired column to a drill string, the method comprising: affixing a plurality of stops on the rod transfer mechanism; locating a moveable block between a number of positions, wherein one stop is engaged in each position; connecting a mechanical linkage to move the block to the desired position.
The invention may also be employed in other environments which utilize drill rod storage locations, columns, rows and/or magazines. For example, the principles of the present invention may be employed in connection with vertical drilling devices. Also, the invention is not limited to use with single blocking member rod transfer mechanisms. For example, the principles of the present invention may be employed with rod transfer mechanisms which can select drill rod from a desired column while blocking the remaining columns.
While the invention will be described with respect to preferred embodiment configurations and with respect to particular devices used therein, it will be understood that the invention is not to be construed as limited in any manner by either such configuration or components described herein. Also, while the particular types of transfer mechanisms are described herein, it will be understood that such particular mechanisms are not to be construed in a limiting manner. Instead, the principles of this invention extend to any environment in which selection of a row or column in a drill rod magazine or other drill rod storage location is desired. These and other variations of the invention will become apparent to those skilled in the art upon a more detailed description of the invention.
The advantages and features which characterize the invention are pointed out with particularity in the claims annexed hereto and forming a part hereof. For a better understanding of the invention, however, reference should be had to the drawings which form a part hereof and to the accompanying descriptive matter, in which there is illustrated and described a preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view illustrating the basic components of a horizontal directional drill device;
FIG. 2 is a section view through a drill rod magazine and a portion of the HDD machine, including the drill rod transfer device;
FIG. 3 is an enlarged view of the drill rod transfer device illustrating the moveable block and the vertically and horizontally offset stops;
FIG. 4 a is a schematic view of the block position selector device in a first position with the moveable block lowered;
FIG. 4 b is a schematic view of the block position selector device in a second position with the moveable block raised; and
FIG. 5 is a perspective view of the lever and latch device on the block position selector device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference will now be made in detail to exemplary aspects of the present invention which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used throughout the drawings to refer to the same or like parts.
FIG. 1 illustrates a typical horizontal directional drill 10 including an operator console 12 , a main frame 14 , a power supply 16 (e.g., a prime mover), a rack frame 18 , a gearbox 20 that is arranged and configured to move back and forth along the longitudinal axis of the rack frame 18 . Spindle 21 can be independently rotated clockwise or counterclockwise. A rod magazine 22 located generally above and to the side of the rack frame 18 stores drill rods 28 . Pipe transfer mechanism 24 is arranged and configured to move the drill rod from the magazine 22 to a position in line with the drill string 26 . Pipe transfer mechanism 24 has an upper and a lower assembly—with one assembly located at each end of the magazine 22 . As used herein, the term lower refers to a position closer/nearer to the surface of the ground, while upper refers to a position that is relatively further from the ground. A vise assembly 30 is located proximate the lower pipe transfer mechanism 24 . Accordingly, in operation, the pipe transfer mechanisms select and transfer individual drill rod 28 from the magazine 22 and into alignment with the drill string 26 and spindle 21 of gearbox 20 .
It will be appreciated that the drill rod 28 is referred to herein as both drill rod and drill pipe. Such terms are used interchangeably herein and are not meant to denote a different type of work piece or structure.
Now turning to FIG. 2 , one of the pipe transfer mechanisms 24 , the magazine 22 , the rack frame 18 , the spindle 21 and the gearbox 20 are illustrated. In FIG. 2 , the pipe transfer mechanism 24 is shown positioned with the rod pocket 60 located directly beneath rod column 61 e . This column 61 e is most distal from the drill string 26 (which is in-line with the spindle 21 in FIG. 2 ). Column 61 a is most proximal to the drill string 26 with each adjacent column 61 b , 61 c , and 61 d moving progressively further away from the drill string 26 . A plurality of stops 63 a - 63 e are included on the pipe transfer mechanism 24 . The stops 63 a - 63 e are arranged in a horizontal and vertical offset from one another (e.g., arranged in a pattern resembling a “stair-step”). Those of skill in the art will appreciate that other patterns and physical locations relative to one another may be used for the stops.
The transfer mechanism 24 includes rod pocket 60 at a first end of the mechanism, and a rod blocking member 64 extending from the rod pocket 60 to the second end of the mechanism. It will be appreciated however, that the rod blocking member 64 may be arranged and configured to other lengths in order to provide the function of blocking drill pipe 28 from exiting non-selected columns of the magazine 22 . On the lower side of the mechanism is a gear rack 66 which is engaged by a driven gear 68 . Movement of the driven gear 68 moves the transfer mechanism 64 back and forth under the magazine and transversely relative to the longitudinal axis of the drill string 26 . By driven, what is meant is that the gear is powered in a manner by which the gear rotates with enough force to move the transfer mechanism. A hydraulic fluid motor (not shown) may be used to drive the gear 68 , with the hydraulic fluid motor powered by a hydraulic pump connected to the power supply 16 (best seen in FIG. 1 ). A pressure limiting device is preferably utilized in connection with the hydraulic pump as will be described in more detail below. The mechanism 24 is supported on the frame 14 with suitable bushings or bearings (not shown).
As noted above, the magazine 22 includes a plurality of columns 61 a - 61 e in which drill rod 28 is stored when not connected to the drill string 26 . The magazine 22 may include a bar 71 at each end for lifting the magazine 22 with a front end loader, crane or other suitable lift assisting device. The bar 71 may provide additional functionality of retaining drill rods 28 within the magazine 22 if the magazine is stored on its side and/or is inadvertently placed or dropped in that position. The columns 61 a - 61 e are formed with outer walls 68 and inner walls 70 . The drill rod 28 is generally placed within the columns 61 a - 61 e (best seen in FIG. 1 ), and gravity is utilized to lower the drill rod 28 within the respective columns to a position where the drill rod 28 drops into the rod pocket 60 when the particular column is selected.
The rod pocket 60 is preferably selected to be a distance from the bottom of the magazine 22 such that only one drill rod 28 is released from the column at a time. However, other drill rod 28 blocking mechanisms may be employed. For further details on the operation and structure of a transfer mechanism 24 , reference may be had, for example, to U.S. Pat. No. 6,814,164, to Mills et al., and titled Pipe Loading Device For A Directional Drilling Apparatus and to U.S. Pat. No. 5,556,253, to Mills et al., and titled Automatic Pipe-Loading Device, each of which are assigned to the assignee hereof. Such patents are hereby incorporated herein and made a part hereof.
Referring now to FIGS. 2 and 3 , moveable block device 72 is mounted on frame 14 at flange 73 . A threaded extent is located through the flange 73 and frame 14 . One or more barrel nuts 74 secures the jacket 75 in place. A cable slides within the jacket 75 and a second end of the cable is connected to a first end of the moveable block 72 . Spring 76 applies an upward force on the moveable block 72 away from the flange 74 . The moveable block 72 is limited to reciprocating movement by bushing 77 .
The first end of the cable is connected to the block position selector device 100 (best seen in FIGS. 4 a , 4 b and 5 ). Preferably the cable is rigid so that it can operate in both a push and pull mode. However, with use of spring 76 , the cable can be a non-rigid wire which is utilized in a pull mode. In this case, spring 76 provides the motive force for the cable to travel through the jacket in the opposition direction when desired.
As the cable is pulled toward the operator station (e.g., toward the block position selector device 100 ), the moveable block 72 moves downward. A second end of the moveable block is arranged and configured to engage the stops 63 a - 63 e , wherein one of the stops is engaged in any selected position. When the transfer member 24 moves away from the drill string 26 by means of the powered gear 68 , the stop 63 a - 63 e appropriate for the selected column 61 a - 61 e contacts the second end of the moveable block 72 . At that time, the pressure limiting device associated with the powered gear 68 causes the transfer member 24 to stop its movement. Such pressure limiting device can act to direct all hydraulic fluid away from the hydraulic fluid motor when a certain pressure is reached (e.g., when one of the stops 63 a - 63 e engages the moveable block 72 ) and/or the pressure limiting device can shunt hydraulic fluid around the hydraulic fluid motor to limit the force the exerted. Other pressure limiting solutions may also be utilized to provide the function of limiting the force applied to the moveable block 72 by the stop 63 .
It will be appreciated that the selected column in FIG. 2 is column 61 e (e.g., the most distal column), and so stop 63 e is illustrated as engaging the second end 73 of the moveable block 72 . In the preferred embodiment, this position of the moveable block 72 is associated with the most lowered position of the moveable block 72 and a fully compressed spring 76 . However, it will be appreciated that other positions of the moveable block 72 may be employed for the most distal column and the spring 76 may be employed in some other positions as a matter of design choice.
FIGS. 4 a and 4 b provide an end view of the transfer mechanism 24 with the moveable block 72 in a lowermost position in FIG. 4 a (e.g., to select column 61 e ) and an uppermost position in FIG. 4 b (e.g., to select column 61 a ). Also shown in FIGS. 4 a and 4 b is the relative position of the lever 101 of selector device 100 when the moveable block 72 is in different positions. The selector lever 101 is engaged with pocket 102 e in FIG. 4 a and is engaged with pocket 102 a in FIG. 4 b.
FIG. 5 illustrates the selector device 100 in more detail. Selector lever 101 pivots about point 104 at its first end. Handle 107 is located at second end 106 . Threaded bosses 109 and 110 are located between the first and second end of selector lever 101 . Spring biased latch device 108 is slidably mounted on selector lever 101 with bosses 109 and 110 extending through elongated channels 111 and 112 , respectively. Nuts, welded attachments or other securing devices may be utilized to retain the spring biased latch device onto selector lever 101 . Spring 113 biases the biased latch device 108 toward the second end 105 of the selector lever 101 . Spring 113 attaches between arm 114 located on the biased latch device 108 and arm 115 located on third member 116 . Third member 116 is fixed to the pivot point 104 and the second end 105 of lever arm 101 . Handle 117 is located on biased latch device 108 . Boss or pin 119 (best seen in FIGS. 4 a and 4 b ) is connected to biased latch device 108 and extends through an elongated channel in selector lever 101 . Pin 119 is thereby normally biased into engagement with a pocket 102 a - 102 e . However, when handle 117 is moved in a direction toward first end 106 of selector lever 101 , then the pin 119 moves out of engagement with a pocket 102 , and the selector lever 101 can be moved between pockets 102 within window 103 . Movement of the selector lever 101 moves the cable within jacket 75 . Preferably handle 117 is physically located in a location where an operator can simultaneously grasp handles 107 and 117 in order to move handle 117 closer to handle 107 against the force of spring 113 .
As noted above, the present invention may be employed in environments other than HDD which utilize drill rod storage locations, columns, rows and/or magazines. For example, the principles of the present invention may be employed in connection with vertical drilling devices. Accordingly, the term column is used to denote a column, row or other collection of drill rod arranged in a line. Also, the invention is not limited to use with single blocking member rod transfer mechanisms. For example, the principles of the present invention may be employed with rod transfer mechanisms which can select drill rod from a desired column while blocking the remaining columns. In this case, the columns are not necessarily emptied of drill rod in order.
While particular embodiments of the invention have been described with respect to its application, it will be understood by those skilled in the art that the invention is not limited by such application or embodiment or the particular components disclosed and described herein. It will be appreciated by those skilled in the art that other components that embody the principles of this invention and other applications therefor other than as described herein can be configured within the spirit and intent of this invention. The arrangement described herein is provided as only one example of an embodiment that incorporates and practices the principles of this invention. Other modifications and alterations are well within the knowledge of those skilled in the art and are to be included within the broad scope of the appended claims. | Mechanical stops are utilized on a rod transfer mechanism, with the stops being offset vertically from one another, to index the rod transfer mechanism of an HDD machine under the appropriate column of a drill rod storage magazine. The stops engage a moveable block which is moved by the operator using a block position selector device. The stops are arranged such that each stop corresponds to a respective column of the magazine. Accordingly, the rod transfer mechanism moves transversely away from the longitudinal axis of the drill string until the selected stop engages the block. The block position selector device is preferably located at the HDD machine operator's station. A cable slidably received within a jacket is employed between the position selector and the block to raise and lower the block. | 4 |
TECHNICAL FIELD OF THE INVENTION
This invention generally relates to a bicycle transport case, and more particularly to a lightweight and compact transport case, which is adjustable in accordance with the size of the bicycle and which requires minimal dismantlement of the bicycle.
BACKGROUND OF THE INVENTION
In recent years, bicycling has become a popular way for keeping physically fit. Many individuals, preferring to avoid the inconvenience and danger of cycling in congested urban areas, transport their bicycles to a desired cycling locale. Also, with the increasing popularity of cycling competitions, national and international cycling events have increased the opportunities for travel with a bicycle. Consequently, there is a need for a bicycle transport case capable of protecting the bicycle during transport. Additionally, to minimize the inconvenience of transportation, it is desirable to have a case that is compact and lightweight.
In addition to increased transport of bicycles, another change in bicycle use has been the use of more sophisticated and delicate gear systems. These systems need to be protected during transport, but without unduly adding weight and bulk to the case.
In the past, bicycle carrying cases have been developed that are relatively bulky and require extensive dismantlement of the bicycle. For example, in Bentler, U.S. Pat. No. 4,353,464, a hard-shelled container for the storage and transportation of a bicycle is disclosed. A disadvantage of the invention is that it requires that the pedals be detached, as well as the wheels and other components of the bicycle. Also, even though the case provides a protective cover over the bicycle, the material of the cover is a bulky plastic, which increases the size and weight of the case. Other examples of hard-shelled cases are Profeta, U.S. Pat. No. 4,378,883, and Bender, U.S. Pat. No. 4,390,088, both of which teach extensive dismantlement of the bicycle.
A case made from a flexible material is disclosed in Garrett, et al., U.S. Pat. No. 3,886,988. A disadvantage of Garrett, however, is that the soft-shelled design of the invention promotes lightweight at the expense of protection of the bicycle from the stress of travel. In particular, the case does not protect the bicycle gears. Another disadvantage of the invention is that the handlebars and the seat must be dismantled before placing the bicycle in the case. Other soft-shelled cases on the market have similar disadvantages and none has mounts to secure the bicycle that are adjustable according to the length of the bicycle frame.
A need has therefore arisen for a bicycle transport case that is lightweight and that protects the bicycle. Additionally, there is a need for a case that requires minimal dismantlement of the bicycle and that permits easy assembly and disassembly of the bicycle by the user when using the case.
SUMMARY OF THE INVENTION
One aspect of the invention is a bicycle transport case having a front mount and a rear mount, attached to a base, for securing the bicycle within the case, which are adjustable according to the length of the bicycle. To this end, at least one mount is slidably engaged with the base, by means of a sliding connector for varying the distance between the front and the rear mounts. Alternatively, at least one of the mounts is angled with respect to the base and is rotatably attached to the base so that this angle may be varied.
Another aspect of the invention is a bicycle transport case that is compact. To this end, the case is designed to carry a bicycle having at least one wheel removed. A front mount and a rear mount are attached to a base. These mounts provide means for attachment to the front and the rear portions of the bicycle, and more particularly, at least one of the mounts provides a means for attachment to the bicycle where the removed wheel would otherwise be attached. This manner of attachment lends itself to the use of quick release assemblies.
Another aspect of the invention is a bicycle transport case for protecting the bicycle from damaging forces that would otherwise cause stress on the bicycle during transport. The case has front and rear mounts for attachment to the front and rear portions of the bicycle, as well as a frame for protecting the rear portion of the bicycle, especially the bicycle gears.
An additional feature of the invention is a wheel pad to protect the wheels during transportation, the wheels having been first removed from the bicycle. This wheel pad is designed to be placed within the case in a manner that further serves to protect the bicycle itself.
Another feature of the invention is an optional handlebar stem that permits the case to be used with bicycles having nonstandard handlebars and avoids the need to rotate the handlebars of a standard bicycle. Another feature of the invention is incorporation of shock absorption means within the mounts.
The invention has technical advantages over prior bicycle transport cases because it protects the bicycle during transport, minimizes the dismantlement prior to transport, adjusts according to the size of the bicycle, and is lightweight and compact.
DESCRIPTION OF THE DRAWINGS
The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as modes of use and further advantages, is best understood by reference to the following description of illustrative embodiments when read in conjunction with the accompanying drawings.
FIG. 1 is a perspective view of the invention, with the cover closed over the bicycle.
FIG. 2 is a perspective view of a portion of the invention, i.e., the base, the mounts, and the frame.
FIG. 3 is a perspective view of a bicycle secured within the invention.
FIG. 4 is a perspective view of the front mount of FIG. 2, with the front fork of a bicycle attached thereto.
FIG. 5 is a perspective view of the rear mount of FIG. 2, with the rear drop outs attached thereto, and further showing a slidable engagement between the rear mount and the base.
FIG. 6 is a partial cross sectional view of the bicycle of FIG. 3, showing the wheel pad, containing the wheels and draped across the top tube of the bicycle.
FIG. 7 is a side view of bicycle handlebars in a downwardly rotated position for use with the invention.
FIG. 8a is a perspective view of an interface stem used to connect the frame of the bicycle to the handlebars.
FIG. 8b is a side view of the interface stem of FIG. 8a and a portion of the frame of a bicycle.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a perspective view of the invention, generally designated as case 10. Case 10 has a base 12 and a cover 11 connected to base 12. In the preferred embodiment, cover 11 is made from a flexible, lightweight material, such as a woven synthetic or canvas. Cover 11 envelopes a bicycle (not shown) inside case 10, preferably by means of two sections which join along a zippered opening.
A plurality of wheels 14 are attached to base 12, and permit mobility of case 10. A strap 16 is connected to cover 11 for pulling case 10. A plurality of handles 18 may also be attached to case 10 for purposes of lifting or pulling case 10.
FIG. 2 is a perspective view of base 12 without cover 11. Base 12 is rectangular in shape, having a length that is approximately equal to the longer end of a range of lengths of bicycle frames. The width of base 12 is slightly less than the widest width of standard bicycle handlebars.
FIG. 2 shows two basic components of the invention, front mount 22 and rear mount 24, which are the means for securing the bicycle within the case 10. In the preferred embodiment of the invention, case 10 is used to carry a bicycle having both wheels removed. Thus, as explained below, both front and rear mounts 22 and 24 are designed for attachment to the front forks 36 and the rear drop outs 38 of a bicycle, as illustrated in FIG. 3. Yet, an important feature of the invention, explained below, is the adjustability of front mount 22 and rear mount 24 to accommodate various sizes of bicycles. This feature of the invention is believed novel regardless of whether the bicycle wheels are removed and some other manner of attaching front mount 22 and rear mount 24 to the bicycle is used.
Front mount 22 is connected to the front of base 12. In the preferred embodiment, front mount 22 is designed for attachment to the front fork 36 of a bicycle, as shown in FIG. 3. Thus, in the preferred embodiment, front mount 22 has a t-shape and the cross portion of front mount 22 may be conveniently attached to the bicycle where the front wheel would otherwise be located. This preferred design lends itself to the use of quick release mechanisms 23, such as are commonly used to attach bicycle wheels to bicycle frames. Nevertheless, the attachment of front mount 22 to front fork 36 is not a necessary feature of the invention, and front mount 22 may be attached to other parts of the front portion of the bicycle. Nor is it necessary that the front wheel be removed. For example, front mount 22 could be attached to the down tube 37 shown in FIG. 3.
Rear mount 24 is connected to the rear of base 12. In the preferred embodiment, rear mount 24 is designed for attachment to the rear drop outs 38 of a bicycle, as shown in FIG. 3. Thus, in the preferred embodiment, rear mount 24 has a t-shape and the cross portion of rear mount 24 may be conveniently attached to the bicycle where the rear wheel would otherwise be located. As with front mount 22, this preferred design lends itself to the use of quick release mechanisms 23. Nevertheless, the attachment of rear mount 24 to rear drop outs 38 is not a necessary feature of the invention, and rear mount 24 may be attached to other parts of the rear portion of the bicycle. Nor is it necessary that the rear wheel be removed. For example, rear mount 24 could be attached to the seat tube 41 shown in FIG. 3.
Rear mount 24 is connected to base 12 by means of a slidable connection. The function of the slidable connection is to permit rear mount 24 to be moved along the length of base 12 to accommodate bicycles of varying lengths. In the preferred embodiment, the slidable connection is implemented by attaching the bottom of rear mount 24, by means of a channel connector 30, to a bar 26, which extends along the part of the length of base 12. Bar 26 may be recessed within a slot in base 12. Channel connector 30 fits around bar 26 and permits connector 30 to slide up and down bar 26. A screw 32 extending through connector 30 and touching bar 26 may be tightened to secure connector 30 to bar 26 at any desired position along bar 12. Thus, when using case 10, rear mount 24 may be slid closer to or farther away from front mount 22 so that the distance between them is selected according to the size of the bicycle.
Although FIG. 2 and other drawings, show rear mount 24 as having a slidable connection with base 12, the invention would be equally functional if front mount 22 rather than rear mount 24 were slidably connected. Such a slidable connection of front mount 22 could be made in the same manner as with rear mount 24, as discussed above.
Another feature of the invention is that the angled configuration of front mount 22 permits another means for adjusting the distance between front mount 22 and rear mount 24 to accommodate varying sizes of bicycles. An attachment means of front mount 22 to base 12 may permit front mount 22 to be rotated one-hundred-eighty degrees so that the angle between front mount 22 and base 12 is reversed. This permits the relative distance of front mount 22 with respect to rear mount 24 to be further capable of adjustment.
Frame 20 is connected to the rear of base 12. The function of frame 20 is to provide rigid side members spaced on both sides of case 10 to protect the bicycle, especially its gears and rear derailleur equipment. Thus, frame 20 may take any shape so long as it includes at least one pair of rigid side members 21. In the preferred embodiment, each side member 21 forms an angle that extends upwardly from base 12. Side members 21 are connected to each other with a cross member 21a for additional strength and stability.
Connected to base 12 are a plurality of straps 34. Straps 34 each have a securing means for enabling connection of one end to another. A preferred method of connecting straps 34 is hook and eye fabric connectors, such as Velcro. Straps 34 are used for connecting bicycle accessories, such as a helmet or pump, within case 10.
A feature of the case 10 is that front mount 22, rear mount 24, and frame 20 have a relatively low profile with respect to base 12. This permits case 10 to be easily folded around or against base 12 when not in use.
Referring now to FIG. 3, a perspective view of the bicycle, secured within cover 11 in accordance with one embodiment of the invention, is shown. For purposes of illustration, cover 11 is transparent. FIG. 3 shows various parts of a standard bicycle, which are relevant to securing the bicycle within case 10. Although FIG. 3 shows the bicycle with its wheels 32 removed, when the bicycle is out of case 10 and assembled for use, a front fork 36 connects the front wheel to the frame, and rear drop outs 38 connect the rear wheel to the frame. The bicycle frame consists of a top tube 31, a down tube 33, a seat tube 35. The bicycle handlebars are generally designated as 39.
The front portion of the bicycle frame is generally that portion including front fork 36 and down tube 33, whereas the rear portion generally includes rear drop outs 38 and seat tube 35. The mid portion is generally the area between down tube 33 and seat tube 35, including the area of their junction near the bicycle pedals (not shown).
In the embodiment of FIG. 3, the bicycle is secured within case 10 with its wheels 32 removed. Front fork 36 is attached to front mount 22 by means of a quick release mechanism 23. Likewise, rear drop outs 38 are attached to rear mount 24 by means of quick release 25. Again, this is only one embodiment, and certain features of case 10, such as frame 20 and the slidable engagement of front mount 22 or rear mount 24, could be used advantageously with a bicycle having its wheels in place. Although not visible in FIG. 3, neither the bicycle seat nor the pedals need be removed when case 10 is in use.
FIG. 4 is a perspective view showing the attachment of front fork 36 to front mount 22, using quick release 23, in further detail. FIG. 4 also illustrates the alternative position of front mount 22 when rotated as discussed above.
FIG. 5 is a perspective view showing the attachment of rear drop outs 38 to rear mount 24, using quick release 25, in further detail. FIG. 5 also illustrates a slidable connection between rear mount 24 and base 12.
FIG. 6 is a cross sectional view of part of the bicycle of FIG. 3, together with a wheel pad 62, which is used with one embodiment of the invention, i.e., when the wheels of the bicycle are removed. Wheel pad 62 is used to wrap wheels 32 after they have been removed. Wheel pad 62 is generally rectangular in shape having a length equal to approximately four times the diameter of each wheel 32 and a width approximately equal to the diameter of each wheel 32. Alternatively, wheel pad 62 could be in the shape of a number of circles, each approximately the size of the bicycle wheel. The primary consideration is that wheel pad 62 be of sufficient size and shape to wrap the wheels. Wheel pad 62 has a securing strap 64 for securing the wheels 32 in wheel pad 62. Wheel pad 62 is filled with a padding material, such as foam rubber.
Once the wheels are secured within wheel pad 62, wheel pad 62 is placed along the mid portion of the bicycle frame, preferably by being straddled over top tube 31 of the bicycle with one wheel on each side of the bicycle frame. The use of wheel pad 62 to wrap wheels 32 for placement against the frame of the bicycle serves the dual purpose of protecting both the wheels and the bicycle. The wheel pad 62, when so used, also adds body to the case 10 so that the widest portions of the bicycle, handlebars 39 and pedals (not shown), do not bulge outward from the rest of the case 10.
FIG. 7 is a side view of a portion of the bicycle, especially handlebars 70. Generally, handlebars 70 are attached to the bicycle near the junction of top tube 31 and down tube 33. A collar 71 receives a stem 73 of the handlebars 70. As indicated in FIG. 7, two adjustment means permit handlebars 70 to be rotated and raised or lowered to suit the size of the user. Specifically, a height adjustment bolt 75 may be tightened and loosened to permit stem 73 to slide within collar 71 so that handlebars 70 may be raised or lowered with respect to the rest of the bicycle frame. A binder bolt 77 may also be tightened or loosened to permit the handpiece 78 of handlebars 70 to be rotated. In FIG. 7, in which only one handpiece 78 is in view, the handpieces 78 are rotated down as would be appropriate for preparing the bicycle to be placed within case 10. The rotating of the handlebars 70 permits case 10 to be more compact by moving the handlebar brake hoods, such as are shown in FIG. 3, downward.
The configuration of FIG. 7 is an alternative to the configuration shown in FIG. 3, which uses a stem interface 81 to connect handlebars 39 to the frame when the bicycle is placed within case 10. Actually, in FIG. 3, handlebars 39 are different from handlebars 70 of FIG. 7. Whereas handlebars 70 of FIG. 7 are presently a standard form of handlebars, handlebars in the shape of handlebars 39 are increasing in popularity. Unlike handlebars 70, stem 89 of handlebars 39 is angled. Handlebars 39 are not easily rotated downward as are handlebars 70. FIG. 3 uses a special interface stem 81, which is used to accommodate this configuration of handlebars 39.
FIG. 8a is a perspective view of interface stem 81. Although interface 81 is pictured with a T-shape, an L-shaped stem would be equally functional. Interface stem 81 has two receiving ends: a frame receiving end 83 and a handlebar receiving end 85, which are generally orthogonal to each other. Interface stem 81 also has straps 87, which may be wrapped around handlebars 39 to further secure handlebars 39 during transport.
FIG. 8b shows interface stem 81 used to attach handlebars 39 to a bicycle frame. Comparing FIG. 8b to FIG. 7, it is seen that rather than rotating handlebars 70, handlebars 39 are first removed from the bicycle frame and interface stem 81 is inserted into the frame in a similar manner as handlebars 39 would be, using frame receiving end 83. Handlebars 39 are then attached to the handlebar receiving end 85 of interface stem 81, using handlebar stem 89. Once handlebars 39 have been inserted into interface stem 81, straps 87 are wrapped around handlebars 39 to keep them in place.
A further advantage of interface stem 81 is that it may optionally be used with standard handlebars, such as shown in FIG. 7, if the user does not wish to rotate the handlebars. When so using interface stem 81, the handlebars are in a downward position and no further adjustment is needed to fit the bicycle within the case 10. This provides an easily reassembled bicycle. The practicality of using interface stem 81 in this manner arises from the fact that binder bolt 77 may be fragile and subject to deterioration with repeated tightening and untightening.
Although not shown in the drawings, an enhancement of the invention is the use of front mount 22 or rear mount 24 as shock absorption means. This could be easily accomplished by modifying the vertical portion of front mount 22 or rear mount 24 so that the vertical portion comprises a sleeve and column, in slidable engagement, such that either the sleeve or the column is a sliding member. A large spring means, such as a coil spring or some other elastic device, placed within the column and sleeve could then provide a rest for the sliding member, permitting the sliding member to move if force is exerted on case 10, but providing a stop. Such force is transmitted to the mount and absorbed by the spring means, thereby preventing stress on the bicycle.
In summary, a bicycle transport case has been described that features the use of a lightweight case capable of protecting the bicycle. The invention also minimizes the amount of assembly and disassembly necessary for using the case 10. In one embodiment, it is only necessary to remove the wheels and adjust the handlebars.
Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiment, as well as alternative embodiments of the invention will become apparent to persons skilled in the art upon reference to the description. It is, therefore, contemplated that the appended claims will cover such modifications that fall within the true scope of the invention. | A case for containing and protecting a bicycle during transport generally comprising a base with a front and a rear mount for attachtment to front and rear portions of the bicycle respectively. A flexible cover contains the bicycle with the case. The case may be made adjustable for different bicycle sizes by slidably engaging one of the mounts on said base. Various embodiments of the case provide a frame for protecting the gears of the bicycle and provide a wheel pad for wrapping and storing the wheels of the bicycle. | 0 |
[0001] This application claims the benefit of priority to U.S. Provisional Patent Application No. 61/456,240, filed Nov. 3, 2010, which is herein incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to pile weatherstripping and other articles made of a pile of filamentary material, hereinafter referred to as yarn, on a support providing a base or backing of material unlike the yarn and especially a pile exclusively of nylon yarn on a backing which contains polypropylene and having a reactive bond between the backing and the yarn provided by an ultrasonic weld. The invention includes method and apparatus for making such weatherstripping and other articles.
BACKGROUND OF THE INVENTION
[0003] Heretofore, pile weatherstripping has been made in large quantities (thousands of feet of weatherstripping per anum) using a process initially developed by Robert Horton (see Horton, U.S. Pat. No. 4,148,953, issued Apr. 10, 1979) where the yarn is helically wound on a traveling band or mandrel, and a backing member of plastic material like the material of the yarn is ultrasonically welded to the yarn along an edge thereof while the yarn and the mandrel move together. The like materials of the yarn and the backing are polypropylene which forms a reactive weld when ultrasonic energy is applied thereto. The following patents also describe the fabrication of pile weatherstripping and also show methods and apparatus for incorporating air and water filtration barrier fins in or along the sides of the pile: Horton, U.S. Pat. No. 4,302,494, issued Nov. 24, 1981; Horton, U.S. Pat. No. 5,060,422, issued Oct. 29, 1991; Johnson et al., U.S. Pat. Nos. 5,338,382, issued Aug. 16, 1994; Johnson, 5,817,390, issued Oct. 6, 1998; and Johnson 5,807,451, issued Sep. 15, 1998. (The patents cited in this paragraph are referenced hereinafter as the “Horton and Johnson patents”).
[0004] It is especially desirable to use nylon for the pile of the weatherstripping because of its wear characteristics and of the ability to absorb crush force as may be applied on the weatherstripping by fenestration products (doors and windows) in which the weatherstripping is installed when such products are forcibly closed. A reactive bond capable of withstanding such forces is especially desirable. It is also desirable to utilize polypropylene in the backing inasmuch as polypropylene is a lower cost material than nylon and provides a competitive advantage in the marketing of the weatherstripping over weatherstripping made entirely of nylon.
[0005] It has been proposed to extrude the backing around the yarn thereby providing a mechanical connection there between, as opposed to a reactive or chemical bond. An extrusion attachment is described in U.S. Pat. No. 5,093,181 to Sanchez, issued Mar. 3, 1992. Interleaved filaments of nylon and polypropylene have also been proposed for providing the pile. Such mixed yarns are mechanically bonded when welded causing the polypropylene to melt and capture the nylon, especially where the polypropylene/nylon yarn is encapsulated in polypropylene to provide the backing for the yarn. Such piles of unlike plastics (Mylar and polypropylene) have been proposed in Ohara et al., U.S. Pat. No. 6,115,566, issued Sep. 5, 2000 and Pawson et al., U.S. Patent Application Publication No. 2009/0258184, published Oct. 15, 2009.
SUMMARY OF THE INVENTION
[0006] It is a feature of the present invention to provide pile articles, and a method and apparatus for making pile articles having piles and backings which support the pile of unlike plastic materials, especially piles of a polyamide (e.g., nylon) and backings containing polypropylene (e.g., backing is of polypropylene material, or a composite of materials one of which is polypropylene), where a reactive chemical bond is provided between piles and backings utilizing ultrasonic welding in the manner similar to that of the above-referenced Horton and Johnson patents.
[0007] Briefly described, the invention provides pile articles, especially pile weatherstripping and a method and apparatus for making such articles where the backing and the pile are of unlike material, especially nylon yarn for the pile and polypropylene containing material for the backing, wherein prior to the welding of the yarn of the pile to the backing, the yarn is first pre-heated using ultrasonic energy to melt an area or region thereof where the yarn is to be ultrasonically welded to the backing. The ultrasonic pre-heating occurs upstream of the location where the yarn is welded to the backing so that the melted region of the yarn can cool and become substantially (or at least partially) solidified. The pre-heated melted nylon of the yarn is then welded to the backing and causes a reactive or chemical weld (or bond) to occur.
[0008] Preferably, the backing is a composite of polypropylene and a polyolefin material which is sold under the trade name Plexar (Plexar is an anhydride modified PP typical of suitable tie-layer resins which may be suitable for use in carrying out aspects of the invention) by Equistar Chemicals of Houston, Tex., USA. It is believed that the Plexar polypropylene mixture, which may be 50% Plexar and polypropylene each by weight, is extruded to make the backing. The mixture may be of other percentages of such materials, if desired. It is believed that the reactive bond is a cross-link polymer bond which provides a strong bond. The ultrasonic welding of the backing to the region of the pre-heated, melted and at least partially solidified yarn is achievable using the long-established process of making pile weatherstripping using ultrasonic welding of like yarn and backing material on a traveling band or mandrel, as per the above-identified Horton and Johnson patents. This cross-link bond or weld is capable of withstanding forces, for example in the neighborhood of 40 psi which may occur in the operation of fenestration products equipped with the weatherstripping. If desired, one or more fins may be part of the weatherstripping as in the above-referenced Johnson patents, each of the one or more fins may be made of a polypropylene film or layer, which is heat-bonded to a non-woven nylon layer or flocking, which is deposited on and bonded to the film.
[0009] The invention also provides a method for making a pile article having pile and a backing which supports the pile of unlike plastic material. The method has the steps of heating ultrasonically the pile along an edge thereof to melt a region of the pile prior to welding the pile to the backing, cooling the region to at least partially solidify the melted pile prior to welding the pile to the backing, and then welding ultrasonically the backing to the pile at such region to attach the backing to the pile. Two of the pile articles may be made by repeating the above steps along each of the two edges of pile wrapped around a moving mandrel or band, and then slitting the wrapped pile along the top and bottom of the mandrel or band to separate the two pile articles from each other.
[0010] Further, a pile article is provided having a backing and pile of polymer material which extends from the backing along one side thereof, where the backing is of a material devoid of the polymer material of the pile, and the backing and the pile were ultrasonically welded to each other along at least a partially solidified melted portion of the pile. In other words, a pile of yarn fused to a backing which supports the pile may be exclusively of a first polymer, where the backing contains a second polymer unlike the first polymer. One or more fins may also extend from the backing with the pile in which the portion of the pile when melted included such one or more fins.
[0011] In general, the pile article, of and made using the present invention have a pile of a polyamide material, such as nylon yarn, attached by fusing the pile to a backing of a polymer material. Preferably, the backing material is unlike that of the polyamide material of the pile in that the polymer material of the backing is or contains a polyolefin, such as polypropylene.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The foregoing and other features and advantages of the invention will become more apparent from a reading of the following description in connection with the accompanying drawings in which:
[0013] FIG. 1 is a top view schematically showing an apparatus for making pile weatherstripping utilizing the invention;
[0014] FIG. 2 is a fragmentary perspective view illustrating one of the two pre-heat ultrasonic horns shown in FIG. 1 ;
[0015] FIG. 3 is a perspective view illustrating one of the pre-heat ultrasonic horns shown in FIG. 1 with the band having the winding of nylon yarn thereon passing through the groove of the pre-heat horn;
[0016] FIG. 4 is a fragmentary view of a flocked film strip which may optionally be used to provide a fin inside the pile; and
[0017] FIG. 5 is a sectional view illustrating the fin strip around the mandrel passing through the groove in one of the pre-heat ultrasonic horns.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Referring to FIG. 1 , there is shown an apparatus 10 similar to that in the above-referenced Johnson and Johnson et al. patents for manufacturing a pair of pile weatherstrips 20 and 22 . Each of the weatherstrips 20 and 22 has a backing of polypropylene blended with Plexar material and extruded into backings 24 from which pile 26 extends. Pile 26 is of polyamide material, preferably nylon yarn. Preferably, the backing may be partially of polypropylene, such as described in more detail later below, but the backing may be entirely or substantially of polypropylene or other non-nylon plastic materials, as desired. The apparatus 10 has a moving band or mandrel 12 of flexible metal guided by rollers 16 along a path in a direction shown by arrow 13 . A winding turret 18 has spools 30 of nylon yarn which winds the yarn helically on the band 12 as it moves through the turret in a downstream direction toward the right as shown in FIG. 1 to provide wound pile 26 . The turret 18 works in the same way as the winding mechanisms in the above-referenced Horton and Johnson patents.
[0019] In order to assure that the band 12 is moving at constant speed, a sensing “piro” unit 17 , which has a wheel rotating with the band near the upstream end of the path shown in FIG. 1 , provides a signal to the driver mechanism for driving the band continuously. The speed of the band 12 is therefore made constant and may be synchronized with the rotation of the spools 30 in the turret 18 so that the density of the yarn of the pile 26 in terms of denier and filament count of yarns per inch may be selected. A suitable rate for practicing the invention may be with the band 12 moving at 2.95 inches per second so as to provide a denier of 1125 and a filament count per inch of 40. Other rate, denier, or filament cost may be selected as desired.
[0020] For pile weatherstrip, pile articles of yarn may be twisted nylon filaments. It will be appreciated, of course, that the pile 26 may be made of nylon monofilaments rather than twisted material. In either case, the term yarn refers to the threads, filaments or twisted threads which are wound on the band 12 . The backings 24 are directed from reels in which the strips constituting the backings are wound and are not shown in FIG. 1 . The backings 24 are guided by pairs of guide rollers 32 and 34 to ultrasonic welding stations 40 and 42 which are spaced from each other along the path of travel of the band 12 . Each station 40 and 42 includes an ultrasonic horn (or head) 50 disposed against first and second fixtures 52 , respectively, which are held against the horn and provide backing 24 for the band 12 so as to facilitate welding by the horns 50 of the backings 24 and the wound pile 26 to each other. The operation of the welding stations 40 and 42 is as described in the above-identified Horton and Johnson patents, which are incorporated herein by reference. For example, the horns 50 may be driven by their drivers at approximately 20 kHz and served to melt both the yarn of pile 26 and the backings 24 so as to provide a fused region wherein there is a reactive or chemical bond, which is believed to include chemical cross-linking of the polymers in the backing and in the yarn, even though they are not of like material. After welding stations 40 and 42 , the pile 26 is cut from band 12 into separate weatherstrips 20 and 22 by a slitter unit 66 shown at the downstream end of the apparatus in FIG. 1 , which provides two wheels with cutting edges disposed above and the other below band 12 to slit pile 26 . For example, pile 26 may be of a height of ¼ inch, and ½ inch wide around band 12 until the two weatherstrips 20 and 22 are cut from band 12 by slitter unit 66 .
[0021] It has been found desirable to provide a composite backing material of PX 6006 anhydride modified polypropylene, which is sold under the trade name Plexar by Equistar Chemicals of Houston, Tex., USA. The PX 6006 and the polymer are separate resins which are mixed, suitably in a 50/50 ratio by weight. The resins of the backing are mixed and fed into an extruder wherein they are extruded into sheets which may be cut into strips providing the backings 24 . Polypropylene is thus one of the resins forming the backing material, but other proportions or percentages in the mixture of resins than set forth above may be used, if desired.
[0022] Ordinarily the unlike or dissimilar plastic materials, namely polypropylene and nylon will not fuse or weld even if heated ultrasonically by the ultrasonic horns 50 in stations 40 and 42 . In other words, the polymers providing the pile and backing do not bond when welded by melting under pressure, which would otherwise be possible if they each were of a common polymer material, such as nylon. According to the present invention, it has been discovered that heating the edges of the yarn pile 26 while wound on the band 20 ultrasonically with pre-heat horns 60 , which may be driven by ultrasonic vibrators or drivers 62 at the same rate as the conventional horns 50 (e.g., 20 kHz) along the edges of the band 12 solves this problem. The pre-heating horns 60 fuses the wound yarn pile 26 in region (area or portion) of the yarn pile which will be ultrasonically welded in ultrasonic welding stations 40 and 42 to backings 24 . Then, the ultrasonic welding in the stations 40 and 42 provides reactive or chemical bonding between the yarn pile 26 and the backings 24 , capable of withstanding forces in opening and closing of windows or otherwise in fenestration products. It is found that the pre-heat horns 60 should be disposed upstream of horns 50 in the stations 40 and 42 by a distance for sufficiently cooling of the yarn pre-heated so as to allow the melted edges along a region of the yarn pre-heated by horns 60 to solidify, at least partially. The distance for cooling depends upon the speed of the band 12 and the density of the yarn as it is wound around the band 12 .
[0023] As shown in FIGS. 2 and 3 , the pre-heat horns 60 are formed with grooves 64 which are sufficiently deep to encompass a region 65 about the edges of the yarn wound around the band 12 . The melted and then at least partially solidify pile region 65 represents the portion of the yarn pile 26 which faced groove 64 when passing there through, i.e., region 65 is the yarn wound along one of the two opposite sides about the width of band 12 and extending partially along upon the upper and lower surface of the band according to the depth of groove 64 . For example, the groove 64 of each horn may be approximately ⅛ inch in depth, and generally semi-circular at least at the bottom thereof, where pile 26 is of height of ¼ inch, and ½ inch wide around band 12 .
[0024] It may be desirable to provide a fin 70 in the weatherstrips. Preferably, the fin 70 includes a strip of polypropylene film material (or layer) 70 a bonded using heat and a suitable bonding material, such as the Plexar mentioned above, to a flocked or non-woven nylon layer 70 b , such as shown in FIG. 4 . The nylon layer 70 b and the film 70 a providing fin 70 are disposed inside the pile 26 wound on the band 12 and are welded both preliminarily by the pre-heat horns 60 and then by horns 50 providing reactive welds between the nylon material of the pile 26 , the polypropylene film 70 a of fin 70 , and the nylon layer 70 b of fin 70 . The fin's nylon layer 70 b along yarn region 65 is pre-heated along with the yarn in grooves 64 of horns 60 and thereby melts and fuses with the yarn, cools to at least partially solidify, and then horns 50 bond the melted fused fin and yarn to the backings 24 . Accordingly, a fin 70 having wearability in use in fenestration products like the nylon yarn of the pile 26 is provided. FIG. 5 shows the location of the fin 70 with the flocking thereon in a groove 64 of one of the pre-heat horns 60 . For purposes of illustration, FIG. 5 shows an example fin 70 only along one of the two opposite sides of band 12 in pile 26 , but the bonded layered materials providing fin may extend (along the top of band 12 shown) to similarly wrap around the other side of the band 12 such that each pile article 20 and 22 when cut has a fin.
[0025] When the pile wrapped around the band 12 arrives on the moving band 12 at ultrasonic welding stations 40 and 42 , the pile regions melted by horns 60 although cooled may still be at an elevated temperature than if horns 60 were not provided. Horns 50 also melt the yarn of pile 26 at least including (or substantially including) the pile region melted earlier by horns 60 thereby attaching backing 24 by reactively or chemically bonding the pile to the backing. Thus, as melting takes place at both horns 50 and horns 60 , then along each side of band 12 its respective horn 60 pre-melts or fuses a region of the pile before such region is further melted or fused at horn 50 when the backing is applied and bonded. The pile 26 of each pile article made, such as weatherstrips 20 and 22 , are composed of multiple partial loops of yarn each having a bottom and two sections extending there from to two free ends, respectively, in a direction away from backing 24 along one side of the backing. The improvement over the Horton and Johnson patent is that when unlike polymer (e.g., plastic) materials are used for the pile and backing, the bottom of the loop and a portion of each of its two sections extending there from are welded to the backing at stations 40 and 42 after being pre-heated as described above by horns 60 to enable the desired bonding of the pile and backing, with or without one or more fins. Since the backing has polypropylene, this reduces the overall cost of the pile articles than if the backing were of nylon, as polypropylene is a lower cost material than nylon.
[0026] From the foregoing description, it will be apparent that there has been provided methods and apparatus for fabricating weatherstripping and other pile articles, such as brushes, having dissimilar materials in the pile and in the backings (or support or base) of the article. Variations and modifications of the herein described method and apparatus within the scope of the invention will undoubtedly suggest themselves to those skilled in the art. Accordingly, the foregoing description should be taken as illustrative and not in a limiting sense. | Pile articles ( 20,22 ), especially pile weatherstripping, and a method and apparatus ( 10 ) for making such articles where the backing ( 24 ) and the pile ( 26 ) are of unlike material, especially nylon yarn for the pile ( 26 ) and polypropylene containing material for the backing ( 24 ), wherein prior to the welding of the pile ( 26 ) to the backing ( 24 ) the pile is first pre-heated using ultrasonic energy to melt the pile in a region ( 65 ) thereof where the pile is ultrasonically welded to the backing and before the weld is made. The ultrasonic melting occurs upstream of the location where the pile ( 26 ) is welded to the backing ( 24 ) so that the ultrasonically pre-heated melted region ( 65 ) of the pile ( 26 ) can cool and become at least partially solidified. Then pile ( 26 ) at the pre-heated melted region ( 65 ) is welded to the backing ( 24 ) and causes a reactive or chemical weld to occur, thereby attaching the pile ( 26 ) to the backing ( 24 ). | 1 |
This invention is a walking aid which can be readily converted from a single cane into a pair of canes.
BACKGROUND OF THE INVENTION
Those who walk with a cane often find themselves in a situation where it would be desirable to have two canes, one for each hand. For example, it is often difficult for a cane user to negotiate a curb with a single cane and much easier if the person has a cane in each hand. Other similar situations will be apparent and are well known to cane users. In response to this need, it has been proposed to provide a hollow cane which houses a second cane on the inside as shown in U.S. Pat. Nos. 1,375,912 and 4,556,075. A major disadvantage of this approach is that the inner cane does not, and almost inherently cannot, have an enlarged rubber foot which promotes traction with the underlying surface.
In another situation, it is often desirable for a person who habitually uses two walking aids to join them together so they are more easily stowed when not in use. In response to this situation, crutches and other walking aids are joined together for stowage as shown in U.S. Pat. No. 5,339,849 and EPO application WO 92/17142.
Other disclosures of interest relative to this invention are found in U.S. Pat. Nos. 2,734,554 and 6,206,019.
SUMMARY OF THE INVENTION
In this invention, a single more-or-less conventional appearing cane is readily broken apart into a pair of canes of sufficient size and strength to provide a cane for each hand of a cane user. Often, a cane user wants to have an additional cane under adverse conditions, e.g. in a poorly lit area when it is cold and raining. Accordingly, an important feature of this invention is the ability to separate the two canes in an easy manner so the canes can be used separately.
When it is desired to use only a single cane, the two canes are attached together in a side-by-side relation to provide a cane assembly. Preferably, the handle of the single cane assembly comprises the two abutted handles of the separate canes and the foot of the single cane assembly comprises the two abutted feet of the separate canes. An important advantage of the side-by-side relationship of the canes is that both canes can be provided with resilient feet. In preferred embodiments of this invention, the load imparted to the single cane by the user is supported by both canes so essentially no load is placed on the connecting mechanism.
It is an object of this invention to provide an improved convertible cane assembly.
A further object of this invention is to provide an improved cane assembly which can be used as a single cane and which is readily disassembled to provide two separate canes.
A more specific object of this invention is to provide a convertible cane assembly having a pair of canes connected in side-by-side abutting relation which can be used as a single cane.
Another object of this invention is to provide a method of using a convertible cane assembly.
These and other objects and advantages of this invention will become more apparent as this description proceeds, reference being made to the accompanying drawings and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a convertible cane of this invention, illustrated in a single cane configuration;
FIG. 2 is a end view of the convertible cane of FIG. 1 ;
FIG. 3 is a top view of the convertible cane of FIGS. 1 and 2 ;
FIG. 4 is an exploded isometric view of the convertible cane of FIGS. 1–3 ;
FIG. 5 is an exploded isometric view of another embodiment of this invention;
FIGS. 6 and 7 are views of the inside of another embodiment of this invention, illustrating a different type of connection;
FIG. 8 is an enlarged view of the connection in the embodiment of FIGS. 6 and 7 ;
FIG. 9 is an end view illustrating another embodiment of this invention;
FIG. 10 is a cross-sectional view of a pair of side-by-side canes illustrating another feature of this invention; and
FIG. 11 is an enlarged isometric view of another embodiment of this invention.
DETAILED DESCRIPTION
Referring to FIGS. 1–4 , a convertible cane assembly 10 of this invention comprises a pair of side-by-side canes 12 , 14 which are joined together by a releasable connection 16 so the cane assembly 10 can be used as a single cane, or the canes 12 , 14 can be used separately and simultaneously. The canes 12 , 14 are of generally conventional appearing construction and each comprise a sturdy upright support 18 , a foot 20 having a resilient pad 22 adjacent the bottom of the support 18 and a handle 24 adjacent the upper end of the support 18 . The resilient pad 22 is of a conventional type used for canes and is typically made of dry natural rubber. The resilient pad 22 is as large as is reasonable and is preferably at least half the cross-sectional area of the upright support 18 . It is preferred that the load imparted by the cane user to the cane assembly 10 be sustained by both canes 12 , 14 so that no substantial force is imparted through the connection 16 .
The connection 16 may be of any suitable type commensurate with its desired functions, which include the ability to keep the canes 12 , 14 together when so desired while providing the ability to separate the canes 12 , 14 in an easy and expeditious manner. One embodiment of the connection 16 is shown in FIGS. 1–4 where the cane 12 provides a pair of vertically spaced inclined passages 26 receiving inclined pegs 28 provided by the cane 14 . The pegs 28 and passages 26 prevent the canes 12 , 14 from separating so long as there is no relative vertical movement between the canes 12 , 14 .
The connection 16 also includes a device 30 selectively preventing vertical movement between the canes 12 , 14 in the form of a tab 32 pivoted to the cane 14 for movement into a pair of aligned grooves 34 in the ends of the handles 24 . The tab 32 and grooves 34 are sized to fit snugly. With the canes 12 , 14 in a side-by-side abutting relation so the pegs 28 fit into the inclined passages 26 and with the tab 32 received in the grooves 34 , the canes 12 , 14 are joined together into the cane assembly 10 and can be used as a single cane.
When the case user desires to use two canes, the tab 32 is simply pivoted to the position shown in FIG. 4 and the canes 12 , 14 shifted vertically as allowed by the inclined pegs 28 and passages 26 . The canes 12 , 14 accordingly separate in a simple efficient manner and can be simultaneously used as two separate canes. When the user desires to use only a single cane, the canes 12 , 14 are connected together and the user grasps both handles 24 with a single hand. Accordingly, the handles 24 in the assembled position of FIGS. 1–3 is preferably not more than about 3 ″ in diameter so it will fit easily into a user's hand. It will be seen that the bottoms of the resilient padded feet 22 are in a common plane so the load imparted by the user is applied more-or-less equally to both pads 22 thereby providing a more stable walking aid.
Referring to FIG. 5 , another embodiment of this invention is illustrated where a convertible cane assembly 40 includes a pair of separate, generally mirror image canes 42 , 44 which are releasably connected by a hook-and-loop fastener 46 comprising a strip of material having a multiplicity of hooks 48 on the cane 42 and a strip of material having a multiplicity of loops 50 on the cane 44 .
Referring to FIGS. 6–7 , another convertible cane assembly 56 of this invention comprises a pair of canes 58 , 60 each comprising an upright support 62 , a foot 64 having a resilient pad 66 adjacent the bottom of the support 62 and a handle 68 adjacent the upper end of the support 62 . The canes 58 , 60 are slightly flattened on the side shown in FIGS. 6 and 7 so that, when connected, the cane assembly 56 appears generally round. A connection 70 secures the canes 58 , 60 together when the user wants to use a single cane and allows the canes 58 , 60 to separate for use separately and simultaneously.
The connection 70 comprises a pair of vertically spaced metal brackets 72 on the cane 60 providing a key hole slot 74 having an enlarged generally circular upper end 76 and a narrow vertical slot 78 . A pair of pins 80 on the cane 62 mate with the key hole slot 74 in a conventional manner. The pins 80 provide an enlarged head 82 and a smaller shank 84 so the enlarged head 82 passes through the upper end 76 of the key hole slot 74 as suggested in FIG. 8 . With the enlarged head 82 received inside the upper end 76 of the slot 74 , the canes 58 , 60 are moved vertically relative to each other thereby moving the pins 80 downwardly in the slot 74 as suggested by the arrow and dashed lines in FIG. 8 . It will be seen that the pins 80 may comprise a round headed screw with the head of a size between the slot 78 and the upper slot end 76 . It will be seen that the enlarged heads 82 prevent horizontal relative movement between the canes 58 , 60 while friction between the pins 80 and slot 74 controls relative vertical movement between the canes 58 , 60 .
Referring to FIG. 9 , another convertible cane 86 of this invention is illustrated comprising single canes 88 , 90 which each include side-by-side upright supports 92 having a resilient padded foot 94 and a handle 96 . A connector 98 releasably secures the canes 88 , 90 together for use as a single cane or as two separate canes. The handles 96 are offset relative to each other so the user grasps only one handle while using the convertible cane 86 rather than grasping both handles as in the embodiments of FIGS. 1–8 .
It often happens that a cane user will know that there will be no need to use two canes and may wish to connect the canes in a more secure manner thereby preventing them from separating inadvertently. To this end, an additional secure connector may be provided. The secure connector 100 may be of any suitable type but is illustrated in FIG. 10 as a simple threaded fastener having a threaded shank 102 embedded in one of the canes 104 extending through a passage 106 in a second cane 108 and a wing nut 110 provided to receive the shank 102 .
Referring to FIG. 11 , there is shown another cane assembly 112 comprising a pair of canes 114 , 116 having means (not shown) analogous to the pegs 28 and passages 26 for holding the canes 114 , 116 together so long as there is no relative vertical movement between the canes 114 , 116 . The cane assembly 112 also comprises a mechanism 118 analogous to the device 30 for preventing relative vertical movement between the canes 114 , 116 . The mechanism 118 comprises a pair of aligned slots 120 , 122 in the canes 114 , 116 near the junction of the upright vertical support and the handle. A tab 124 is pivoted for movement about an axis 126 provided by a screw or pin (not shown). With the tab 124 in the position shown in FIG. 11 , i.e. wholly within the confines of the slot 120 , the canes 114 , 116 are freed for relative vertical movement so the canes 114 , 116 can be separated for individual use. To secure the canes 114 , 116 together, they are placed in side-by-side relation and the tab 124 pivoted into the slot 122 whereby the canes 114 , 116 are prevented from relative vertical movement and are thus connected together.
A further feature of the cane assembly 112 is an supplementary locking mechanism comprising a bolt 128 . If the user decides that separate use of the canes 114 , 116 will not be necessary, the tab 124 is pivoted into the slot 122 and the bolt 128 is passed through aligned openings 130 , 132 preventing the tab 124 from pivoting to the position shown in FIG. 11 . A nylon nut 134 in the bottom of the passage 132 provides sufficient friction to retain the bolt 128 in place. The bolt 128 preferably provides a head 136 that can be grasped between the thumb and forefinger for readily advancing the bolt 128 into the nylon nut 134 . To provide a convenient storage location for the bolt 128 , a storage passage 138 is provided in the handle 140 rearward of the slots 120 , 122 . The storage passage 138 also provides a nylon nut 140 for frictionally holding the bolt 128 so it will not be lost.
It will accordingly be seen that the convertible canes of this invention comprise two separately useable canes having exteriors which, in the configuration of a single cane, are side-by-side and the exteriors face each other.
Although this invention has been disclosed and described in its preferred forms with a certain degree of particularity, it is understood that the present disclosure of the preferred forms is only by way of example and that numerous changes in the details of operation and in the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed. | A convertible cane assembly comprises a pair of canes which can be used separately by a cane user. The canes include connections for securing the canes in side-by-side relation to provide a single cane which can be used in a normal manner. An important feature of the connections is the ability to easily separate the canes. In the single cane version, loads are preferably transferred through the entire length of both canes, meaning that the connections do not have to carry substantial loads. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an electron emission unit and a flat panel display device employing the electron emission unit. More particularly, the present invention relates to an electron emission unit that may prevent an anode electric field from penetrating a gate electric field so as to avoid arcing, and also may prevent a hazardous voltage being applied to an electron emitting unit and other elements. The present invention also relates to a flat panel display device employing the electron emission unit as a backlight unit.
[0003] 2. Description of the Related Art
[0004] In general, flat panel display devices may be classified into emissive display devices and non-emissive display devices. Examples of the emissive display devices may include a cathode ray tubes (CRT), a plasma display panel (PDP) that may emit light using plasma generated by applying a strong voltage, a field emission display (FED) that may emit light by exciting a phosphor screen with electrons emitted from a plane cathode, a vacuum fluorescent display (VFD) that may emit light by creating thermal electrons through a voltage supplied in a filament and accelerating the electrons by means of a grid so that the electrons may reach an anode to collide with phosphors already patterned and illuminate for displaying information, and an organic light emitting device (OLED) that may emit light by running current through a fluorescent or phosphorescent organic thin film to make electrons and holes meet in the organic layer. An example of the non-emissive display device may include a liquid crystal display (LCD) that may use a liquid crystal that is in a state between solid and liquid and may act as a shutter to selectively transmit or block light according to voltage.
[0005] Among these examples, the LCD may be of light weight and low power consumption. However, the LCD may not display an image that is observable in a dark place because it is a light receiving display device and thus the image is produced not by self-emitting but by external light. Accordingly, the LCD may include a backlight unit at a rear side of the LCD apparatus to emit light. In this case, the LCD may also display an image that is observable even in a dark place.
[0006] While there may be different backlight units, a linear light source and a point light source may be used as an edge type backlight unit. Particularly, a cold cathode fluorescent lamp (CCFL) having electrodes at both ends of a tube may be commonly used as a linear light source. A light emitting diode (LED) may be commonly used as a point light source.
[0007] The CCFL may offer strong white light generation, superior brightness and uniformity, and easy large-scale design. However, the CCFL may operate using a high frequency alternating current. Additionally, the CCFL may operate within a narrow temperature range for light output to occur.
[0008] The LED may operate with less brightness and uniformity than the CCFL. This may be especially true in a larger size LED. Also, high power may be consumed when reflecting and transmitting light due to the light source being located on a rear side. Further, the structural complexities of a LED may result in higher production costs. However, the LED may operate using direct current instead of a high frequency alternating current. Additionally, the LED may offer improved power and temperature characteristics, smaller size and longer life expectancy.
[0009] Recently, electron emission units employed as backlight units using a planar light emitting structure have been proposed to solve the above-mentioned problems. These electron emission type backlight units may exhibit low power consumption and relatively uniform brightness, even over wider regions, as compared to a CCFL and the like.
[0010] For example, an electron emission unit employed as a backlight unit may have an upper substrate and a lower substrate that may be separated from each other by a predetermined gap. A fluorescent layer and an anode may be sequentially disposed on a bottom surface of the upper substrate, and a cathode may be disposed on a top surface of the lower substrate. Also, a stripe-patterned electron emitting unit may be disposed on the cathode.
[0011] An exemplary operation of the electron emission unit may include a predetermined voltage applied between the anode and the cathode. Electrons may be emitted from the electron emitting unit disposed on the cathode. The electrons emitted from the electron emitting unit may collide with the fluorescent layer and may excite fluorescent materials in the fluorescent layer, such that visible light may be emitted with extra energy.
[0012] However, since the cathode may be formed over the entire surface of the lower substrate, a high voltage directly applied between the anode and the cathode may cause local arcing. Due to the local arcing, the electron emission employed as a backlight unit may not ensure uniform brightness over the entire display surface. Furthermore, the local arcing may damage the anode and cathodes, the fluorescent layer, and the electron emitting layers, thereby shortening the life of the electron emission unit employed as a backlight unit.
SUMMARY OF THE INVENTION
[0013] The present invention is therefore directed to an electron emission unit and a flat panel display device employing the electron emission unit, which substantially overcome one or more of the problems due to the limitations and disadvantages of the related art.
[0014] It is therefore a feature of an embodiment of the present invention to provide an electron emission unit that may enhance brightness and uniformity by improving structures of a cathode, a gate electrode, and an electron emitting unit and also may extend the life of the electron emission unit by preventing inside deterioration, and a flat panel display device employing the electron emission unit as a backlight unit.
[0015] At least one of the above and other features and advantages of the present invention may be realized by providing an electron emission type backlight unit that may include a front substrate and a rear substrate, a gate electrode, an insulating unit disposed on the gate electrode, a cathode disposed on the insulating unit that intersects the gate electrode, a first opening formed in the cathode that exposes the gate electrode, a second opening formed in the insulating unit that exposes the gate electrode, in which the second opening connects to the first opening, an electron emitting disposed on the cathode that exposes the gate electrode, in which the electron emitting unit is formed to trace along a boundary of the cathode that defines the first opening, an auxiliary gate electrode disposed on the gate electrode, in which the auxiliary gate electrode passes through the first opening and the second opening, an anode, and a light emitting unit.
[0016] The cathode and the gate electrode may intersect each other at right angles.
[0017] The gate electrode may be patterned in two or more stripes. The ends of the stripes of the gate electrode may be electrically connected to each other. The gate electrode may be on a top surface of the rear substrate and a bottom surface of the gate electrode may not be larger than the top surface of the rear substrate.
[0018] The insulating unit may be larger than an area where the gate electrode and the cathode intersect each other.
[0019] The auxiliary gate electrode may have the same shape as the first or second openings and may have a diameter smaller than the diameters of each of the first and second openings. The auxiliary gate electrode may be taller than the electron emitting unit.
[0020] The cathode may be patterned in two or more stripes. The ends of the stripes of the cathode may have curved shapes. The cathode may be on a top surface of the rear substrate and a bottom surface of the cathode is not larger than the top surface of the rear substrate.
[0021] The first opening may be defined as a closed shape, the closed shape may include a circle shape, an oval shape, a square shape, or a star shape. The second opening may be defined as a closed shape, the closed shape may include a circle shape, an oval shape, a square shape, or a star shape.
[0022] The first opening may be larger than the second opening. The first opening and the second opening may be concentric. The first opening and the second opening may be substantially the same diameter and may be substantially concentric.
[0023] The first opening and the second opening may have substantially the same shape. The first opening may have a different shape than the second opening.
[0024] The electron emitting unit may be formed to protrude and cover the boundary of the cathode that may define the first opening, in which the protrusion may not exceed the boundary of the insulating unit that may define the second opening.
[0025] At least one of the above and other features and advantages of the present invention may be realized by providing a flat panel display device that may include the electron emission type backlight unit, and a display panel that may include a light receiving element that controls light received from the electron emission type backlight unit.
[0026] The light receiving element may be a liquid crystal.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The above and other features and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:
[0028] FIG. 1 illustrates an exploded view of an electron emission type backlight unit according to an exemplary embodiment of the present invention;
[0029] FIG. 2 illustrates a cross-sectional view taken along line II-II of FIG. 1 ;
[0030] FIG. 3 illustrates a cross-sectional view of a modified electron emission type backlight unit of FIG. 2 ;
[0031] FIG. 4 illustrates an exploded view of an electron emission type backlight unit according to another exemplary embodiment of the present invention;
[0032] FIG. 5 illustrates a cross-sectional view of a modified electron emission type backlight unit of FIG. 2 ;
[0033] FIG. 6 illustrates an exploded view of an electron emission type backlight unit according to still another exemplary embodiment of the present invention;
[0034] FIG. 7 illustrates an exploded view of an electron emission type backlight unit according to yet another exemplary embodiment of the present invention;
[0035] FIG. 8 illustrates an exploded view of an electron emission type backlight unit and a flat panel display according to an exemplary embodiment of the present invention; and
[0036] FIG. 9 illustrates a partially enlarged cross-sectional view taken along line VII-VII of FIG. 8 .
DETAILED DESCRIPTION OF THE INVENTION
[0037] Korean Patent Application No. 10-2005-0068531, filed on Jul. 27, 2005, in the Korean Intellectual Property Office, and entitled: “Electron Emission Type Backlight Unit and Flat Panel Display Device Having the Same,” is incorporated by reference herein in its entirety.
[0038] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are illustrated. The invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the figures, the dimensions of layers and regions and the size of components may be exaggerated for clarity of illustration. It will also be understood that when a layer is referred to as being “on” another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may also be present.
[0039] Further, it will be understood that when a layer is referred to as being “under” another layer, it can be directly under, and one or more intervening layers may also be present. In addition, it will also be understood that when a layer is referred to as being “between” two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present. Like reference numerals refer to like elements throughout.
[0040] FIG. 1 illustrates an exploded view of an electron emission type backlight unit according to an exemplary embodiment of the present invention. FIG. 2 illustrates a cross-sectional view taken along line II-II of FIG. 1 .
[0041] Referring to FIGS. 1 and 2 , the electron emission type backlight unit may include a front substrate 120 and a rear substrate 100 that face each other. An anode 600 and a light emitting unit 700 may be sequentially disposed on a bottom surface of the front substrate 120 . Although the light emitting unit 700 is disposed under the anode 600 in FIGS. 1 through 2 , the present invention is not limited thereto and the light emitting unit 700 may be stacked over the anode 600 without departing from the spirit and scope of the present invention
[0042] The light emitting unit 700 may be made of, for example, a fluorescent or phosphorescent material. The anode 600 may be made of, for example, a metal thin film that may be disposed on a top surface of the light emitting unit 700 . Alternately, a transparent electrode (not illustrated) may be disposed on a surface of the light emitting unit 700 and serve as the anode 600 . The transparent electrode may be stacked over the entire surface of the front substrate or may be patterned in stripes. Of course if the transparent electrode is employed and serves as the anode, the metal thin film may be omitted, and vice versa.
[0043] In an exemplary operation, an external voltage, below a withstand voltage, may be applied to the anode 600 in order to accelerate electron beams and increase the brightness of the backlight unit.
[0044] An inner space 1 10 formed between the front substrate 120 and the rear substrate 100 should be maintained in a vacuum. Otherwise, particles existing between the front and rear substrates 120 and 100 and electrons emitted from the electron emitting unit 400 may collide with each other and generate ions. These ions may cause ion sputtering, may deteriorate the light emitting unit 700 , and may badly affect the life and quality of the electron emission type backlight unit. Also, since electrons accelerated by the anode 600 may collide with residual particles and lose energy, these electrons may not transmit sufficient energy upon collision with the light emitting unit 700 , further resulting in a reduction in luminous efficiency. Accordingly, the inner space 110 between the rear substrate 100 and the front substrate 120 may be hermetically sealed in a vacuum state along laminated ends of the front substrate 120 and the rear substrate 100 .
[0045] An exemplary structure of the electron emission type backlight unit will now be explained in detail. Referring to FIG. 2 , the rear substrate 100 may be made of, for example, a glass material or the like, and a gate electrode 200 may be made of, for example, a transparent conductive material, such as indium tin oxide (ITO), indium zinc oxide (IZO), In 2 O 3 , or the like, or a metal, such as Mo, Ni, Ti, Cr, W, Ag, or the like, and may be formed on the rear substrate 100 . Of course, the gate electrode 200 may be made of other conductive materials.
[0046] The gate electrode 200 may have various shapes. For example, the gate electrode 200 may be patterned in stripes as illustrated in FIG. 1 . Alternately, although not illustrated, the gate electrode 200 may be patterned so that two or more stripes form one stripe. In other words, the gate electrode 220 may be formed in one large stripe pattern consisting of a plurality of stripes. The ends of the stripes of the gate electrode 200 may be connected to one another so as to receive a voltage necessary for accelerating electrons emitted from the electron emitting unit 400 . In this regard, the stripe-patterned gate 200 may drive the electron emission type backlight unit with less power consumed.
[0047] A glass paste, for example, may be screen-printed several times over the entire surface of the rear substrate 100 to cover the gate electrode 200 and form an insulating unit 500 made of, for example, silicon oxide or silicon nitride. Of course, the insulting unit 500 may be made of other electrically insulating materials.
[0048] The insulating unit 500 may be formed at an area where the gate electrode 200 and a cathode 300 intersect each other. Alternately, the insulating unit 500 may be larger than the area where the gate electrode 200 and the cathode 300 intersect each other. For example, when the gate electrode 200 and the cathode 300 may be patterned in stripes, the insulating unit 200 may be disposed in respective areas where the stripes of the gate electrode 200 and the stripes of the cathode 300 intersect each other. Accordingly, the insulating unit 500 is not limited to its shape or size unless, for example, an electrical short occurs.
[0049] The insulating unit 500 may have a second opening 520 formed in the area where the gate electrode 200 and the cathode 300 intersect each other. The second opening 520 may provide electrical communication between an auxiliary gate electrode 220 and the gate electrode 200 . The second opening 520 may also prevent the penetration of an anode electric field into a cathode-gate electric field.
[0050] The cathode 300 may be made of a material such as nickel, cobalt, iron, gold, silver or the like, and may be stacked on a top surface of the insulating unit 500 to intersect the gate electrode 200 . The cathode 300 may have various shapes, and for example, may be patterned in stripes as illustrated in FIG. 1 . Alternately, the cathode 300 may be patterned so that two or more stripes form one stripe. In other words, the cathode 300 may be formed in one large stripe pattern consisting of a plurality of stripes. The ends of the stripes of the cathode 300 may be connected to one another so as to supply electrons to the electron emitting unit 400 . In this regard, the stripe-patterned cathode 300 may drive the electron emission type backlight unit with less power consumed.
[0051] The cathode 300 also may have a first opening 320 formed in the area where the gate electrode 200 and the cathode 300 intersect each other. The first opening 320 may provide electrical communication between the auxiliary gate electrode 220 and the gate electrode 200 . The first opening 320 may also prevent the penetration of an anode electric field into a cathode-gate electric field.
[0052] The first opening 320 and the second opening 520 of the insulting unit 500 may be concentric. Additionally, the first and second openings 320 and 520 may not be limited in size, unless, for example, the auxiliary gate electrode 220 contacts edges of the first and second openings 320 and 520 . That is, the first opening 320 may be larger than the second opening 520 as illustrated in FIG. 2 , or the first and second openings 320 and 520 may have the same diameter to form an opening 321 , as illustrated in FIG. 3 . However, when considering failure that may occur due to an electrical short from the gate electrode 200 during the formation of the cathode 300 , the first opening 320 may be larger than the second opening 520 .
[0053] The electron emitting unit 400 may be stacked on a top surface of the cathode 300 to receive electrons from the cathode 300 . The electron emitting unit 400 may be disposed along an edge of the first opening 320 . However, when considering that a cathode-gate electric field may be stronger at a top end or a side end of the cathode 300 , the electron emitting unit 400 may be stacked along the edge of the first opening 320 .
[0054] The electron emitting unit 400 may have a circular shape. Also, similar to the first and second openings 320 and 520 , which may have circular shapes, the electron emitting unit 400 may have a cylindrical shape. In the cylindrical shape, the electron emitting unit 400 may be in the cathode-gate electric field produced by the auxiliary gate electrode 220 . The electron emitting unit 400 is not limited to the circular or cylindrical shapes, and may have other various shapes, which will be explained later.
[0055] The electron emitting unit 400 may be made of, for example, a carbon-based material having a low work function such as carbon nanotube (CNT), graphite, diamond, diamond like carbon (DLC), fullerene (C60), carbon nanohorn or the like.
[0056] The electron emitting unit 400 may be formed, for example, by thick-film printing and patterning a carbon-based paste through drying, exposure, and development, or may be formed by chemical vapor deposition (CVD), physical vapor deposition (PVD) or the like.
[0057] The auxiliary gate electrode 220 may be disposed in the first and second openings 320 and 520 . The auxiliary gate electrode 220 may prevent an anode electric field from penetrating into an electric field formed by the cathode 300 and the gate electrode 200 . Additionally, the auxiliary gate electrode 220 may efficiently control electron emission due to a voltage applied to the gate electrode 200 .
[0058] The auxiliary gate electrode 220 may be made of, for example, a transparent conductive material, such as ITO, IZO, In 2 O 3 , or the like, or a metal, such as Mo, Ni, Ti, Cr, W, Ag, or the like. Of course, the auxiliary gate 220 may be made of other conductive materials. In this regard, the auxiliary gate electrode 220 may be made of the same material as the gate electrode 200 . However, if contact resistance, which may occur between the auxiliary gate electrode 220 and the gate electrode 200 , is not critical, and interface affinity is acceptable, the conductive material of the auxiliary gate electrode 220 may be different from that of the gate electrode 200 .
[0059] The auxiliary gate electrode 220 may have the same shape as the first and second openings 320 and 520 . As illustrated in FIG. 1 , similar to the first and second openings 320 and 520 having circular shapes, the auxiliary gate electrode 220 may have a circular or cylindrical shape. However, the auxiliary gate electrode 220 is not limited to the circular or cylindrical shape, and may have other shapes. Also, the auxiliary gate electrode 220 may not contact edges of the first and second openings 320 and 520 .
[0060] In this exemplary structure, the electrons emitted from the electron emitting unit 400 may be effectively controlled by a voltage applied to the auxiliary gate electrode 220 .
[0061] The rear substrate 100 and the front substrate 120 may be sealed together using, for example, a sealing material. The sealing member may be, for example, a sealing glass frit. In this case, the sealing glass frit may be in a soft state and may be coated on an edge of the rear substrate 100 using, for example, dispensing, screen printing, or the like. Any water contained in the sealing glass frit may be removed using a drying process.
[0062] The rear substrate 100 and the front substrate 120 may be aligned and the sealing glass frit may be sintered at high temperature to completely seal the rear substrate 100 and the front substrate 120 . The inner space 110 , between the rear substrate 100 and the front substrate 120 , may be made into a vacuum state using, for example, an exhaust port (not illustrated).
[0063] In this exemplary structure, a high voltage for electron emission may be directly applied between the anode 600 and the cathode 300 without local arcing. Accordingly, a voltage may be applied, electrons may be emitted from the electron emitting unit 400 and the emitted electrons may be accelerated by an electric field formed by the anode 600 on the front substrate 120 . These electrons may collide with the light emitting unit 700 to emit visible light.
[0064] FIG. 3 is a cross-sectional view of a modified electron emission type backlight unit of FIG. 2 . The modified electron emission type backlight unit of FIG. 3 is different from the electron emission type backlight unit of FIG. 2 in that the opening 520 of the insulating layer 500 and the opening 320 of the cathode 300 have substantially the same diameter to form the opening 321 .
[0065] However, as illustrated in FIG. 2 , the insulating unit 500 and the cathode 300 may be made of, for example, different materials, and to form the openings 520 and 320 , respectively, a wet or dry etching may be employed using the same etchant. In this case, the rates of etchings may be different, in view of the different materials, such that the openings 520 and 320 may have different diameters.
[0066] Alternately, the insulating unit 500 and the cathode 300 may be subjected to laser beams or ion beams to respectively form the openings 520 and 320 . The portions of the insulating unit 500 and the cathode 300 exposed to the beams may have the same area. Accordingly, the openings 520 and 320 may have the same diameter, as illustrated in FIG. 3 . In short, the openings 520 and 320 may have different diameters as illustrated in FIG. 2 or may have the same diameter as illustrated in FIG. 3 without departing from the sprit or scope of the present invention.
[0067] FIG. 4 is an exploded view of an electron emission type backlight unit according to another exemplary embodiment of the present invention. An explanation will now be made focusing on differences from the exemplary embodiment of FIGS. 1 and 2 .
[0068] Referring to FIG. 4 , the front substrate 120 and the rear substrate 100 face each other. The anode 600 and the light emitting unit 700 may be sequentially disposed on a bottom surface of the front substrate 120 . The anode 600 , the inner space 110 , and the light emitting unit 700 of FIG. 4 may be equal or similar to those of FIGS. 1 and 2 , and thus a detailed explanation thereof will not be given.
[0069] The rear substrate 100 may be made of, for example, a glass material or the like. The gate electrode 200 may be made of, for example, a transparent conductive material, such as ITO, IZO, In 2 O 3 , or the like, or a metal, such as Mo, Ni, Ti, Cr, W, Ag, or the like, and may be formed on a top surface of the rear substrate 100 . Of course, the gate electrode 200 may be made of other conductive materials.
[0070] The gate electrode 200 may have various shapes. In the present exemplary embodiment, the gate electrode 200 may be formed over the entire top surface of the rear substrate 100 , unlike the exemplary embodiment of FIGS. 1 and 2 . That is, in the exemplary embodiment of FIGS. 1 and 2 , the gate electrode 200 may be patterned in stripes or formed in one large stripe pattern consisting of two or more stripes. However, in the present exemplary embodiment of FIG. 4 , the gate electrode 200 may be formed over the entire top surface of the rear substrate 100 . Accordingly, the manufacturing process may be simplified and the rate of defects may be reduced.
[0071] A glass paste, for example, may be screen-printed several times over the entire surface of the rear substrate 100 to cover the gate electrode 200 , and form the insulating unit 500 made of, for example, silicon oxide or silicon nitride. Of course, the insulating unit 500 may be made of other electrically insulating materials.
[0072] The insulating unit 500 may be formed at an area where the gate electrode 200 and the cathode 300 intersect each other. Alternately, the insulating unit 500 may be larger than the area where the gate electrode 200 and the cathode 300 intersect each other. Accordingly, the insulating unit 500 is not limited to its shape or size, unless, for example, an electrical short occurs.
[0073] The insulating unit 500 may have the second opening 520 formed in the area where the gate electrode 200 and the cathode 300 intersect each other. The second opening 520 of FIG. 4 may be equal or similar to that of FIGS. 1 and 2 , and thus a detailed explanation thereof will not be given.
[0074] The cathode 300 may be made of a material such as nickel, cobalt, iron, gold, silver, or the like, and may be stacked on a top surface of the insulating unit 500 to intersect the gate electrode 200 . As illustrated in FIG. 4 , the cathode 300 may be formed over the entire top surface of the rear substrate 100 .
[0075] The cathode 300 in the exemplary embodiment of FIGS. 1 and 2 may have various shapes, for example, may be patterned in stripes. Alternately, the cathode 300 of FIGS. 1 and 2 may be formed in one large pattern consisting of two or more stripes, and the ends of the stripes of the cathode 300 may be connected to one another to receive a voltage. However, the cathode 300 in the present exemplary embodiment of FIG. 4 may be formed over the entire top surface of the rear substrate 100 . Accordingly, the manufacturing process may be simplified and the rate of defects may be reduced.
[0076] The cathode 300 may have the first opening 320 formed in the area where the gate electrode 200 and the cathode 300 intersect each other. The first opening 320 of FIG. 4 may be equal or similar to that of the exemplary embodiment illustrated in FIGS. 1 and 2 , and thus a detailed explanation thereof will not be given. The first opening 320 and the second opening 520 of the insulating unit 500 may be concentric.
[0077] The electron emitting unit 400 may be stacked on a top surface of the cathode 300 to receive electrons from the cathode 300 . The electron emitting unit 400 of FIG. 4 may be equal or similar to that of the exemplary embodiment illustrated in FIGS. 1 and 2 , and thus a detailed explanation thereof will not be given.
[0078] Also, the shape of the auxiliary gate electrode 220 may be equal or similar to that of the exemplary embodiment illustrated in FIGS. 1 and 2 , and thus a detailed explanation thereof will not be given.
[0079] The rear substrate 100 and the front substrate 120 may be sealed together using, for example, a sealing member. The sealing member may be equal or similar to that of the exemplary embodiment illustrated in FIGS. 1 and 2 , and thus a detailed explanation thereof will not be given.
[0080] In this exemplary structure, a high voltage for electron emission may be directly applied between the anode 600 and the cathode 300 without local arcing. Accordingly, a voltage may be applied, electrons may be emitted from the electron emitting unit 400 and the emitted electrons may be accelerated by an electric field formed by the anode 600 on the front substrate. These electrons may collide with the light emitting unit 700 to emit visible light.
[0081] FIG. 5 illustrates a cross-sectional view of a modified electron emission type backlight unit of FIG. 2 . An explanation will now be made focusing on differences from the electron emission type backlight unit of FIGS. 1 and 2 .
[0082] Referring to FIG. 5 , the front substrate 120 and the rear substrate 100 may face each other, and the anode 600 and the light emitting unit 700 may be sequentially stacked on a bottom surface of the front substrate 120 .
[0083] The anode 600 may be made of, for example, a metal thin film as described above, and thus a detailed explanation thereof will not be given. A transparent electrode (not illustrated) made of, for example, ITO may be disposed on a surface of the light emitting unit 700 . In this case, the metal thin film may be omitted, and the transparent electrode may serve as an anode for receiving a voltage necessary for electronic beam acceleration, and vice versa. The order of stacking the anode 600 and the light emitting unit 700 may be changed without departing from the spirit and scope of the present invention.
[0084] The inner space 110 may be formed between the front substrate 120 and the rear substrate 100 with a predetermined distance between them. The inner space 110 should be maintained in a vacuum state as described above, and thus a detailed explanation thereof will not be given.
[0085] The rear substrate 100 may be made of, for example, a glass material, and the gate electrode 200 may be made of a transparent conductive material, such as ITO, IZO, or In 2 O 3 , or the like or a metal, such as Mo, Ni, Ti, Cr, W, Ag, or the like, and may be formed on the rear substrate 100 . The gate electrode 200 may be made of other conductive materials.
[0086] The gate electrode 200 may have various shapes. For example, the gate electrode 200 may be patterned in stripes as illustrated in FIG. 1 . Also, the gate electrode 200 may be formed in one large stripe pattern consisting of two or more stripes. The ends of the stripes of the gate electrode 200 may be connected to one another. Alternately, the gate electrode 200 may be formed over the entire surface of the rear substrate 100 facing the front substrate 120 as described above with reference to FIG. 4 .
[0087] A glass paste, for example, may be screen-printed several times over the entire surface of the rear substrate 100 to cover the gate electrode 200 and form the insulating unit 500 made of, for example, silicon oxide or silicon nitride. Of course, the insulating unit 500 may be made of other electrically insulating materials.
[0088] The insulating unit 500 may be equal or similar to that described in the previous exemplary embodiments, and thus a detailed explanation thereof will not be given. The insulating unit 500 may have the second opening 520 formed in an area where the gate electrode 200 and the cathode 300 intersect each other.
[0089] The cathode 300 may be made of a material such as nickel, cobalt, iron, gold, silver or the like, and may be stacked on a top surface of the insulating unit 500 to intersect the gate electrode 200 .
[0090] The cathode 300 may be patterned in stripes. The cathode 300 may have various shapes, and for example, may be patterned in stripes as illustrated in FIG. 1 . The cathode 300 may be formed in one large stripe pattern consisting of two or more stripes. The ends of the stripes of the cathode 300 may be connected to one another. Alternately, the cathode 300 may be formed over the entire surface of the rear substrate 100 as described above, and thus a detailed explanation will not be given.
[0091] The cathode 300 may have the first opening 320 in the area where the gate electrode 200 and the cathode 300 intersect each other. The first opening 320 may be equal or similar to that of FIGS. 1 and 2 , and thus a detailed explanation will not be given.
[0092] An electron emitting unit 400 a may be formed on a top surface of the cathode 300 . Considering that a cathode-gate electric field may be stronger at a top end or side end of the cathode 300 , the electron emitting unit 400 a may be coated along an edge of the first opening 320 to cover the top end and the side end of the cathode 300 . Thus, the electron emitting unit 400 of FIGS. 1 and 2 may be stacked on the end of the cathode 300 . However, the electron emitting unit 400 a of FIG. 5 may be stacked on both the top end and the side end of the cathode 300 .
[0093] The electron emitting unit 400 a may have a circular shape. Accordingly, electrons emitted from the electron emitting unit 400 a may be efficiently controlled by a cathode-gate electric field produced by the auxiliary gate electrode 220 . The other feature of the electron emitting unit 400 a may be the same or similar to that of FIGS. 1 and 2 , and thus a detailed explanation will not be given.
[0094] The auxiliary gate electrode 220 may be disposed in the first and second openings 320 and 520 . The other feature of the auxiliary gate electrode 220 may be the same or similar to that of FIGS. 1 and 2 , and thus a detailed explanation thereof will not be given.
[0095] In this exemplary structure, the electrons that may be emitted from the electron emitting unit 400 a may be effectively controlled by a voltage applied to the auxiliary gate electrode 220 .
[0096] The rear substrate 100 and the front substrate 120 may be sealed together using, for example, a sealing member.
[0097] In this exemplary structure, a high voltage for electron emission may be directly applied between the anode 600 and the cathode 300 without local arcing. Accordingly, a voltage may be applied, electrons may be emitted from the electron emitting unit 400 a, and the emitted electrons may be accelerated by an electric field formed by the anode 600 on the front substrate 120 . These electrons may collide with the light emitting unit 700 to emit visible light.
[0098] FIG. 6 illustrates an exploded view of an electron emission type backlight unit according to still another exemplary embodiment of the present invention. The front substrate 120 , the anode 600 , and the light emitting unit 700 may be the same or similar to those described in the previous exemplary embodiments of FIGS. 1 through 5 , and thus a detailed explanation thereof will not be given.
[0099] Referring to FIG. 6 , the rear substrate 100 may be made of, for example, a glass material or the like, and the gate electrode 200 may be made of, for example, a transparent conductive material, such as ITO, IZO, or In 2 O 3 , or the like, or a metal, such as Mo, Ni, Ti, Cr, W, or Ag, or the like, and may be formed on the rear substrate 100 . Of course, the gate electrode 200 may be made of other conductive materials.
[0100] The gate electrode 200 may have various shapes. For example, the gate electrode 200 may be patterned in stripes as illustrated in FIG. 1 . Alternately, the gate electrode 200 may be formed over the entire surface of the rear substrate 100 facing the front substrate 120 as described above, and thus a detailed explanation thereof will not be given.
[0101] A glass paste, for example, may be screen-printed several times over the entire surface of the rear substrate 100 to cover the gate electrode 200 and form the insulating unit 500 made of, for example, silicon oxide or silicon nitride. Of course, the insulating unit 500 may be made of other electrically insulting materials.
[0102] The other features of the insulating unit 500 may be the same or similar to as those of the exemplary embodiments of FIGS. 1 through 5 , and thus a detailed explanation thereof will not be given. The insulating unit 500 may have the second opening 520 in an area where the gate electrode 200 and the cathode 300 intersect each other.
[0103] The second opening 520 may have a square shape. The square second opening 520 may provide electrical communication between the auxiliary gate electrode 220 and the gate electrode 200 . The second opening 520 may also prevent an anode electric field from penetrating into a cathode-gate electric field. However, the second opening 520 is not limited to the square shape, and may have, for example, closed curve shapes such as circle, oval, star, or the like.
[0104] The cathode 300 may be made of a material such as nickel, cobalt, iron, gold, silver or the like, and may be stacked on a top surface of the insulating unit 500 to intersect the gate electrode 200 . The cathode 300 may be patterned in stripes. The cathode 300 may have various shapes, and for example, may be patterned in stripes as illustrated in FIG. 1 . Alternately, the cathode 300 may be formed over the entire surface of the rear substrate 100 as described above, and thus a detailed explanation thereof will not be given. The cathode 300 may have the first opening 320 in the area where the gate electrode 200 and the cathode 300 intersect each other.
[0105] The first opening 320 may have the same shape as the second opening 520 . In the present exemplary embodiment, the second opening 520 may have a square shape, and the first opening 320 also may have a square shape. However, the first and second openings 320 and 520 are not limited to the square shapes, and may have, for example, closed curve shapes such as circle, oval, star or the like. Additionally, the first opening 320 may have a different shape from the shape of the second opening 520 if, for example, the auxiliary gate electrode 220 communicates with the gate electrode 200 .
[0106] The first opening 320 may provide electrical communication between the auxiliary gate electrode 220 and the gate electrode 200 . The first opening 320 may also prevent an anode electric field from penetrating into a cathode-gate electric field.
[0107] The first opening 320 and the second opening 520 of the insulating unit 500 may be concentric. The first and second openings 320 and 520 may have various sizes unless, for example, the auxiliary gate electrode 220 contacts edges of the first and second openings 320 and 520 .
[0108] The electron emitting unit 400 a may be stacked on a top surface of the cathode 300 to receive electrons emitted from the cathode 300 . The electron emitting unit 400 a may be disposed along an edge of the first opening 320 . However, when considering that a cathode-gate electric field may be stronger at a top end or side end of the cathode 300 , the electron emitting unit 400 a may be coated along the edge of the first opening 320 to cover the top end and the side end of the cathode 300 .
[0109] The electron emitting unit 400 a may have a square shape. Similar to the first and second openings 320 and 520 that may have square shapes, the electron emitting unit 400 a may have a square or square pillar shape to be efficiently present in a cathode-gate electric field produced by the auxiliary gate electrode 520 . However, the electron emitting unit 400 a is not limited to the square or square pillar shape, and may have, for example, closed curve shapes such as circle, oval, star, or the like. The other features of the electron emitting unit 400 a may be the same or similar to those described in FIGS. 1 through 5 , and thus a detailed explanation thereof will not be given.
[0110] The auxiliary gate electrode 220 may be disposed in the first and second openings 320 and 520 . The auxiliary gate electrode 220 may prevent an anode electric field from penetrating into an electric field formed by the cathode 300 and the gate electrode 200 and may control electron emission due to a voltage applied to the gate electrode 200 .
[0111] The auxiliary gate electrode 220 may be made of, for example, a transparent conductive material, such as ITO, IZO, In 2 O 3 , or the like, or a metal, such as Mo, Ni, Ti, Cr, W, Ag, or the like. Of course, the auxiliary gate 220 may be made of other conductive materials. In this regard, the auxiliary gate electrode 220 may be made of the same material as the gate electrode 200 . However, if contact resistance, which may occur between the auxiliary gate electrode 220 and the gate electrode 200 , is not critical, and interface affinity is acceptable, the conductive material of the auxiliary gate electrode 220 may be different from that of the gate electrode 200 .
[0112] The auxiliary gate electrode 220 may have the same shape as the first and second openings 320 and 520 . Similar to the first and second openings 320 and 520 that may have square shapes, the auxiliary gate electrode 220 may have a square or square pillar shape. However, the auxiliary gate electrode 220 is not limited to the square or square pillar shape, and may have, for example, closed curve shapes such as circle, oval, star or the like. Further, the auxiliary gate electrode 220 may not contact edges of the first and second openings 320 and 520 .
[0113] The rear substrate 100 and the front substrate 120 may be sealed together using, for example, a sealing material. The sealing material may be the same or similar to that of FIGS. 1 through 5 , and thus a detailed explanation thereof will not be given.
[0114] In this exemplary structure, a high voltage for electron emission may be directly applied between the anode 600 and the cathode 300 without local arcing. Accordingly, a voltage may be applied, electrons may be emitted from the electron emitting unit 400 a, and the emitted electrons may be accelerated by an electric field formed by the anode 600 on the front substrate 120 . These electrons may collide with the light emitting unit 700 to emit visible light.
[0115] FIG. 7 illustrates an exploded view of an electron emission type backlight unit according to yet another exemplary embodiment of the present invention. The front substrate 120 , the anode 600 , and the light emitting unit 700 may be the same as those of FIGS. 1 through 6 , and thus a detailed explanation will not be given.
[0116] Referring to FIG. 7 , the rear substrate 100 may be made of, for example a glass material or the like, and the gate electrode 200 may be made of a transparent conductive material, such as ITO, IZO, In 2 O 3 , or the like, or a metal, such as Mo, Ni, Ti, Cr, W, Ag, or the like, and may be formed on the rear substrate 100 .
[0117] The gate electrode 200 may have various shapes. For example, the gate electrode 200 may be patterned in stripes as illustrated in FIG. 7 . However, the gate electrode 200 may be formed over the entire surface of the rear substrate 100 as described above, and thus a detailed explanation thereof will not be given.
[0118] A glass paste, for example, may be screen-printed several times over the entire surface of the rear substrate 100 to cover the gate electrode 200 and form the insulating unit 500 made of, for example, silicon oxide or silicon nitride. Of course, the insulating unit 500 may be made of other electrically insulating materials.
[0119] The other features of the insulating unit 500 may be the same or similar to those described in FIGS. 1 through 6 , and thus a detailed explanation thereof will not be given. The insulating unit 500 may have the second opening 520 in an area where the gate electrode 200 and the cathode 300 intersect each other.
[0120] The second opening 520 may have a square shape. However, the second opening 520 is not limited to the square shape, and may have, for example, closed curve shapes such as circle, oval, star or the like.
[0121] The cathode 300 made of a material such as nickel, cobalt, iron, gold, silver or the like, and may be stacked on a top surface of the insulating unit 500 to intersect the gate electrode 200 . The cathode 300 may be patterned in stripes or formed in one large stripe pattern consisting of two or more stripes. Additionally, the ends of the stripes of the cathode 300 may have curved shapes, as illustrated in FIG. 7 .
[0122] The cathode 300 may be formed around the first opening 320 and may have the same shape as the first opening 320 . The cathode 300 may be patterned to allow electrical communication in a direction where the stripes may be formed. The first opening 320 may have, for example, a square shape and the opening formed on the cathode 300 may also have a square shape. However, the cathode 300 may be patterned to have a different shape from the first opening 320 , if, for example, the electron emitting unit 400 a may be stacked around the first opening 320 . That is, if the electron emitting unit 400 a may be stacked to emit electrons and the cathode 300 may allow electrical communication, the cathode 300 may have any shape.
[0123] The cathode 300 may have the first opening 320 in an area where the gate electrode 200 and the cathode 300 intersect each other.
[0124] The first opening 320 may have the same shape as the second opening 520 . In the present exemplary embodiment, the second opening 520 may have a square shape and the first opening 320 also may have a square shape. However, the first and second openings 320 are not limited to the square shapes, and may have, for example, closed curve shapes such as circle, oval, star, or the like. Additionally, the first opening 320 and the second opening 520 may have different shapes as described above, and thus a detailed explanation thereof will not be given.
[0125] The first opening 320 and the second opening 520 of the insulating unit 500 may be concentric. However, the first and second openings 320 and 520 may not be limited in size unless, for example, the auxiliary gate electrode 220 contacts edges of the first and second openings 320 and 520 .
[0126] The electron emitting unit 400 a may be stacked on a top surface of the cathode 300 to receive electrons from the cathode 300 . The electron emitting unit 400 a may be disposed along an edge of the first opening 320 . However, when considering that a cathode-gate electric field may be stronger at a top end or a side end of the cathode 300 , the electron emitting unit 400 a may be coated along the first opening 320 to cover the top end and the side end of the cathode 300 .
[0127] The electron emitting unit 400 a may have a square shape. Similar to the first and second openings 320 and 520 that may have square shapes, the electron emitting unit 400 a may have a square or square pillar shape to be efficiently present in a cathode-gate electric field produced by the auxiliary gate electrode 520 . However, the electron emitting unit 400 a is not limited to the square or square pillar shape, and may have, for example, closed curve shapes, such as circle, oval, star or the like. The other features of the electron emitting unit 400 a may be the same or similar to those described in FIGS. 1 through 6 , and thus a detailed explanation thereof will not be given.
[0128] The auxiliary gate electrode 220 may be disposed in the first and second openings 320 and 520 . The auxiliary gate electrode 220 may prevent an anode electric field from penetrating into an electric field formed by the cathode 300 and the gate electrode 200 . Additionally, the auxiliary gate electrode 220 may control electron emission due to a voltage applied to the gate electrode 200 .
[0129] The auxiliary gate electrode 220 may be made of, for example, a transparent conductive material, such as ITO, IZO, In 2 O 3 , or the like, or a metal, such as Mo, Ni, Ti, Cr, W, Ag, or the like. Of course, the auxiliary gate 220 may be made of other conductive materials. In this regard, the auxiliary gate electrode 220 may be made of the same material as the gate electrode 200 . However, if contact resistance, which may occur between the auxiliary gate electrode 220 and the gate electrode 200 , is not critical, and interface affinity is acceptable, the conductive material of the auxiliary gate electrode 220 may be different from that of the gate electrode 200 .
[0130] The auxiliary gate electrode 220 may have the same shape as the first and second openings 320 and 520 . Similar to the first and second openings 320 and 520 having square shapes, the auxiliary gate electrode 220 may have a square or square pillar shape. However, the auxiliary gate electrode 220 is not limited to the square or square pillar shape, and may have, for example, closed curve shapes such as circle, oval, star or the like. Furthermore, the auxiliary gate electrode 220 may have a size so that the auxiliary gate electrode 220 does not contact edges of the first and second openings 320 and 520 .
[0131] The rear substrate 100 and the front substrate 120 may be sealed using, for example, a sealing member. The sealing member may be the same or similar to those described in FIGS. 1 through 6 , and thus a detailed explanation thereof will not be given.
[0132] In this exemplary structure, a high voltage for electron emission may be directly applied between the anode 600 and the cathode 300 without local arcing. Accordingly, a voltage may be applied, electrons may be emitted from the electron emitting unit 400 a, and the emitted electrons may be accelerated by an electric field formed by the anode 600 on the front substrate 120 . These electrons may collide with the light emitting unit 700 to emit visible light.
[0133] FIGS. 8 and 9 illustrate an exploded view and a partial cross-sectional view, respectively, of an exemplary flat panel display device, such as an exemplary liquid crystal display panel, employing an electron emission unit as a backlight unit according to an exemplary embodiment of the present invention.
[0134] Referring to FIG. 8 , an electron emission type backlight unit 800 may supply light to a liquid crystal display panel 900 of the liquid crystal display device. A flexible printed circuit board 910 may transmit an image signal to the liquid crystal display panel 900 . The flexible printed circuit board 910 may be attached to the liquid crystal display panel 900 . The electron emission type backlight unit 800 may be disposed to the back of the liquid crystal display panel 900 .
[0135] The electron emission type backlight unit 800 may receive power through a connecting cable 700 , may discharge light 750 through a front surface 751 of the backlight unit 800 , and may supply the light 750 to the liquid crystal display panel 900 .
[0136] The electron emission type backlight unit 800 and the liquid crystal display panel 900 will now be explained with reference to FIG. 9 . The electron emission type backlight unit 800 of FIG. 8 may be the electron emission type backlight unit according to the previous exemplary embodiments of the present invention.
[0137] Referring to FIG. 9 , for purposes of discussion, the electron emission type backlight unit 800 may be the electron emission type backlight unit described in the exemplary embodiment of FIGS. 1 and 2 . Of course, the electron emission type backlight unit 800 may be the electron emission type backlight unit described in the other exemplary embodiments, as well.
[0138] In an exemplary operation, external power may be applied and an electric field may be formed between the cathode 300 and the gate electrode 200 . The cathode 300 may supply electrons, which may be discharged from the electron emitting unit 400 . The discharged electrons may collide with the light emitting unit 700 to generate visible light V. The visible light may be emitted toward the liquid crystal display panel 900 .
[0139] The exemplary liquid crystal display panel 900 may include a first substrate 505 , a buffer layer 510 may be formed on the first substrate 505 , and a semiconductor layer 580 may be formed in a predetermined pattern on the buffer layer 510 . A first insulating layer 520 may be formed on the semiconductor layer 580 , a gate electrode 590 may be formed in a predetermined pattern on the first insulating layer 520 , and a second insulating layer 530 may be formed on the gate electrode 590 . The first and second insulating layers 520 and 530 may be etched by dry etching to expose a part of the semiconductor layer 580 . A source electrode 570 and a drain electrode 610 may be formed in a predetermined area including the exposed part. A third insulating layer 540 may be formed, and a planarization layer 550 may be formed on the third insulating layer 540 . A first electrode 620 may be formed in a predetermined pattern on the planarization layer 550 , and a part of the third insulating layer 540 and the planarization layer 550 may be etched to form a conductive path between the drain electrode 610 and the first electrode 620 . A transparent second substrate 680 may be separately manufactured from the first substrate 505 , and a color filter layer 670 may be formed on a bottom surface 680 a of the second substrate 680 . A second electrode 660 may be formed on a bottom surface 670 a of the color filter layer 670 , and a first alignment layer 630 and a second alignment layer 650 facing a liquid crystal layer 640 may be respectively formed on the first electrode 620 and the second electrode 660 . A first polarization layer 500 may be formed on a bottom surface of the first substrate 505 , and a second polarization layer 690 may be formed on a top surface 680 b of the second substrate 680 . A protective film 695 may be formed on a top surface 690 a of the second polarization layer 690 . A spacer 560 partitioning the liquid crystal layer 640 may be formed between the color filter layer 670 and the planarization layer 550 .
[0140] An exemplary operation of the liquid crystal display panel 900 will now be explained briefly. A potential difference may be generated between the first electrode 620 and the second electrode 660 due to an external signal controlled by the gate electrode 590 , the source electrode 570 , and the drain electrode 610 . The arrangement of the liquid crystal layer 640 may be determined by the potential difference. Visible light V supplied by the backlight unit 800 may be blocked or transmitted according to the arrangement of the liquid crystal layer 640 . The transmitted light may pass through the color filter layer 670 and may radiate color, thereby realizing an image.
[0141] Although the exemplary liquid crystal display panel 900 is a thin film transistor-liquid crystal display (TFT-LCD) in FIG.9 , the liquid crystal display panel 900 is not limited thereto, and may be other various light receiving display panels. The liquid crystal display panel 900 employing the exemplary electron emission unit as a backlight unit may have enhanced image brightness and prolonged life, given the improved brightness and prolonged life of the electron emission type backlight unit 800 .
[0142] Although the electron emission device of the present invention may be used as the backlight unit, the electron emission device of the present invention may be used as an electron emission display device that may produce an image as well. That is, since the cathode and the gate electrode intersect each other, pixels may be defined. For example, the area where the cathode and the gate electrode intersect may be selected and a luminescent layer, for example, a fluorescent layer corresponding to a proper color may be disposed on a surface of the anode corresponding to the selected area. Therefore, three intersectional areas or three groups of intersectional areas may define a pixel that may have a Red, Green, and Blue light source. Since the electron emission display device may effectively block an anode electric field, gradation may be obtained by controlling a voltage applied to the gate electrode.
[0143] As described above, the electron emission type backlight unit and the flat panel display device employing the same according to the present invention may have the following advantages.
[0144] A strong electric field may be uniformly formed using the electron emitting unit, and brightness and uniformity may be improved, direct arcing between the cathode and the anode may be avoided, and the deterioration of the electron emitting units may be prevented.
[0145] Also, the electron emitting unit may operate without an undue increase in temperature so that the life of the light emitting unit may be extended.
[0146] Exemplary embodiments of the present invention have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. Accordingly, it will be understood by those of ordinary skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention as set forth in the following claims. | An electron emission type backlight unit which may include a front substrate and a rear substrate, a gate electrode, an insulating unit disposed on the gate electrode, a cathode disposed on the insulating unit that intersects the gate electrode, a first opening formed in the cathode to expose the gate electrode, a second opening formed in the insulating unit to expose the gate electrode, in which the second opening connects to the first opening, an electron emitting unit disposed on the cathode that exposes the gate electrode, in which the electron emitting unit is formed to trace along a boundary of the cathode that defines the first opening, an auxiliary gate electrode disposed on the gate electrode, in which the auxiliary gate electrode passes through the first opening and the second opening; and an anode and a light emitting unit. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a cabin construction of a wheel loader having a vehicle body with a driver's section at a rear position, a backhoe detachably attached to a rear end of the vehicle body and a cabin for covering the driver's section.
2. Description of the Related Arts
In a known wheel loader of the above-noted type, the cabin is constructed integrally, i.e. undetachably with the driver's section so as to cover the top and four lateral sides of the same. With this integral construction, there arises an inconvenience if the vehicle is to selectively cope with two different modes of use, where the vehicle is used with connection with the backhoe and where the vehicle is used without the backhoe connection, since the former mode requires an additional space for accommodating a control unit for the backhoe which, when installed, projects within the cabin. In order to accommodate with these different cases, there must be provided several cabins of different constructions.
More particularly, when it is necessary to equip the vehicle with the backhoe. A cabin having an undetachable flat rear wall cannot accommodate the backhoe control unit, whereby the entire cabin must be replaced by another cabin having a rearwardly projecting rear wall. Needless to say, such replacement of entire cabin is troublesome and costly.
The present invention attends to this drawback of the prior art.
SUMMARY OF THE INVENTION
In order to overcome the above-described drawback, in a cabin construction of a wheel loader of the above type, the cabin according to the present invention comprises: a cabin body for covering a top, front and right and left sides of a driver's section and having a rear opening; and first and second rear doors selectively and detachably attached to a rear side of the cabin body; the first rear door being used when a backhoe is connected with the vehicle body whereas the second rear door being used when the backhoe is not connected with the vehicle body.
Functions and effects of the above characterizing construction will be described next.
With the detachable and exchangeable rear doors, the entire cabin body does not need to be replaced in order to accommodate the two different modes, i.e. having the backhoe-connected and without the backhoe connected. All that is needed is the replacement of the rear door which is much lighter and thus easier to handle than the entire cabin body. Therefore, this feature significantly reduces the trouble of replacement and also the costs of the cabin construction.
Further, according to one preferred embodiment, the first rear door when attached to the cabin body has a rearward extention for accommodating a control unit and a pair of foot rests within the cabin when the backhoe is attached to the wheel loader.
With this further feature of the invention, the control unit and the foot rests attached to the backhoe may be accommodated within the cabin at the additional space formed by the rearward extension of the first rear door without significantly limiting the free foot space or lower space for the driver. Therefore, the driver seated at his rearward-directed seat position can comfortably carry out a backhoe operation. Conversely, when the backhoe is not necessary, the second rear door having a substantially flat face is attached. In this case, the cabin may be formed compact without unnecessary rearward extension.
In most of the conventional wheel loader vehicles, at his forward-directed seat position for operating the front loader, the driver uses as the foot rests the front portions of the wheel fenders or portions of the vehicle frame positioned at approximately same height.
Then, according to a further embodiment of the invention, the wheel loader includes an engine hood for covering the top of an engine, the hood being formed concave at a rear top portion thereof, a wheel fender portion exposed by the concave rear top portion and foot rests of a backhoe device together constituting foot step means.
With this additional feature of the invention, there occurs no variation in the height of the foot rests for the seated driver between the backhoe-connected condition where he is seated with the rearward orientation and the backhoe-unconnected condition where he is seated with the forward orientation. Further, the driver can easily switch over and set his seat position simply by rearwardly pivoting the seat located on the engine hood. Moreover, since the portions of the wheel fender are used as the foot rests in this construction, the rear end of the cabin can be formed compact, hence, the entire vehicle can be formed still more compact in its longitudinal dimension.
In the above construction, if the base portion of the portal frame is disposed outwards in the vehicle transverse direction relative to the wheel fender portions, this wheel loader obtains a ROPS (Roll-Over Protection Structure) feature.
Further and other objects, features and effects of the invention will become apparent from the following more detailed description of the embodiments of the invention with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Accompanying drawings illustrate one preferred embodiment of the present invention relating to a cabin construction of a wheel loader; in which,
FIG. 1 is an overall side view of the loader mounted with a backhoe,
FIG. 2 is a plane view of major portions inside the cabin,
FIG. 3 is an overall side view of the loader with the backhoe being detached therefrom,
FIG. 4 is a exploded perspective view of the cabin, and
FIG. 5 is a perspective view showing an attaching position for a portal frame.
DESCRIPTION OF THE PREFERRED EMBODIMENT
One preferred embodiment of the invention will be particularly described hereinafter with reference to the accompanying drawings.
FIG. 1 shows a wheel loader equipped with a cabin A to which the present invention relates. This wheel loader includes a front body 1 and a rear body 2 interconnected with each other while being pivotable about a vertical axis P, such that the travelling loader can make a turn by operating a steering wheel 3 mounted on the rear body 2 for expanding or contracting a hydraulic cylinder 4 thereby to pivot the front body 1 relative to the rear body 2. The front body 1 carries at a forward position thereof a front loader device 10 including a lift arm 6 vertically pivotable by a lift hydraulic cylinder 5, an excavating bucket 7 pivotably connected to a leading end of the lift arm 6, a pivot arm 9 for pivoting the bucket 7 via a pivot hydraulic cylinder 8. On the other hand, the rear body 2 mounts therein an unillustrated engine and also mounts thereon a driver's section 12 covered with the cabin A.
Incidentally, in this wheel loader, the rear body 2 permits, at a rear end thereof, a detachable attachment of a backhoe device 13. FIG. 1 shows this backhoe device 13 being attached to the rear body 2, whereas, FIG. 3 shows the backhoe 13 being detached from the same where only the front loader device 10 is to be used. This backhoe device 13 includes a control unit 14 extending from a pivotal base of the device 13 upwardly and forwardly relative to the loader body and a pair of foot rests 20. These foot rests 20 are bolt-connected to opposed sides of the control unit 14 and are configurated with a rearward upslope as illustrated.
In connection with the above-described backhoe arrangement, a driver's seat 15 of the driver's section 12 is pivotable about a vertical axis selectively and lockably into a front-facing position for steering the wheel loader and for operating the front loader device 10 and a rear-facing position for operating the backhoe device 13.
Further, as illustrated in FIGS. 1 and 2, an engine hood 40, which covers the top of the engine, is formed concave at its rear top portion so as to provide sufficient lower area and foot clearance for the driver seated at the seat 15 locked in the rear-facing position, such that the driver may maintain his vertical seating position substantially constant regardless of the seat (i.e. front-facing or rear-facing) position. The bottom face of the engine hood 40 is comprised of portions 19 forming the wheel fenders. These wheel fender portions 19 and the foot rests 20 of the backhoe 13 together are used as foot rest means for the driver seated at the rearwardly oriented driver's seat 15.
Next, a construction of the cabin A will be particularly described.
Referring to FIG. 4, this cabin A includes a cabin body 16 for covering a top and front and right and left sides of the driver's section 12 and having a rear opening and first and second rear doors 17 and 17a selectively and detachably attached to a rear side of the cabin body 16 so as to close the rear opening of the same. Much of the front and right and left sides of the cabin body 16 is formed of transparent glass plates 18 so as to provide the driver with a high driving and working visibility in these directions. First, FIG. 2 illustrates one case where the first rear door 17 is attached to the cabin body 16. As shown, this first rear door 17 has a rearward projection for accommodating the control unit 14 and the pair of foot rests 20 of the backhoe device 13 within the cabin A when attached to the same. Similar to the cabin body 16, the first rear door 17 is formed mostly of transparent glass plates 18 except for its metal frame structure 21 (FIG. 4), such that a good visibility is provided to the driver when he is seated rearwards also. Further, as shown in FIG. 4, this first rear door 17 is detachably attached, via a right and left positioned pair of hinges 22 and 22 fixed to its upper edge, to the upper rear end of the cabin body 16, with the door 17 being pivotable about a horizontal axis so as to open or close the rear opening of the cabin body 16. The hinges 22 are disconnectably bolt-connected with a corresponding pair of attaching seats 24 fixedly secured to a portal frame structure 23 incorporated at the rear end position of the cabin body 16. Also, a pair of stopper elements 25 fixed to opposite inner and lower side faces of the door 17 come into snap-in engagement with a corresponding pair of buckle type locking elements 26 fixed to corresponding lower side opposed positions on the cabin body 16, whereby the first rear door 17 may be locked at the closed position relative to the cabin body 16 and also may be released and pivoted into an opened position by releasing the snap-in engagement between the stopper elements 25 and the locking elements 26.
For manually effecting the above door movements, there is provided a door opening/closing mechanism including a pair of stays 27 fixedly secured to the metal frame structure 21, which structure acts as an outer peripheral frame at opposite upper side portions of the first rear door 17, a further pair of stays 28 fixedly secured to upper and lower center positions of the opposed sides of the portal frame structure 23 of the cabin body 16 and a corresponding pair of air suspension cylinders 30 with ball joints 29, such that the first rear door 17 is urged towards its opening direction by the cylinders 30 and may be locked at its closed position.
Further, as shown in FIG. 2, the base portion of this portal frame structure 23 is disposed outwards in the vehicle transverse direction relative to the wheel fender portions 19. This arrangement serves to strengthen the ROPS feature.
Conversely, when the driver uses only the front loader device 10 and the backhoe device 13 is not necessary, the backhoe device 13 is detached from the rear body 2 as illustrated in FIG. 3, and the first rear door 17 is also detached from the cabin body 16. Thereafter, the second rear door 17a, which has a flat shape, is attached to the cabin body 16 in substantially the same manner as the attachment of the first rear door 17. That is, this second rear door 17a is also detachably attached to the cabin body 16 by bolt-connecting a right and left positioned pair of hinges 22 fixed to its upper edge to the attaching seats 24 of the cabin body 16, with the door 17a being pivotable about the horizontal axis so as to open or close the rear opening of the cabin body 16. Also, the second rear door 17a is lockable at its closed position and releasable therefrom by means of the buckle type locking elements 26.
With the above-described construction, the same cabin body 16 may be used for both of the backhoe-connected mode and the backhoe-unconnected mode. That is, for the change of the operational condition, the replacement between the first rear door 17 and the second rear door 17a alone is necessary, whereby the replacement operation may be significantly facilitated and the costs of the entire cabin may be reduced.
FIG. 5 shows an attaching portion where a lower end of the portal frame structure 23 is attached to the rear body 2. This lower end of the portal frame structure 23 fixedly carries an attaching plate 31 for a bolt-connection with the rear body 2, such that four corner portions of the attaching plate 31 are connected with a rear body frame 32 by means of bolts, respectively. In this construction, there is provided an arrangement which facilitates the connections of the bolts 33 which is difficult from the inner side of the cabin A. This arrangement permits the bolt connection from the outer side of the cabin A which is much easier than that from the inner side of the same. More particularly, the metal frame structure 21 of the cabin body 16 defines a cutout 34 at each corner thereof, through which cutout 34 the connecting bolt 33 is connected. After this bolt connection is completed, the cutout 34 is closed by a cover member 35. That is, at an inner peripheral edge face of the cutout 35, there is fixedly attached a connecting element 36 for the cover connection, such that after the attachment of the cover element 35 an outer surface of this cover element 35 may be disposed flush with an outer suface of the metal frame structure 21 of the cabin body 16. | A cabin construction of a wheel loader having a vehicle body with a driver's section at a rear position, a backhoe detachably attached to a rear end of the vehicle body and a cabin for covering the driver's section. The improvement includes a detachable rear end cabin door construction which permits an easy and economical exchange of the rear door as necessary for the varying uses of the vehicle. A first door is used when the vehicle body is attached with the backhoe whereas a second door is used when the vehicle body is used without the backhoe. The feature has eliminated the necessity of costly and troublesome replacement of the entire cabin construction and is advantageous also for forming a compact the rear end of the vehicle. | 4 |
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to on-line preparation of a solution intended for a medical procedure, in particular of sodium chloride or bicarbonate solution for hemodialysis. The on-line preparation in view takes place in a cartridge containing a powdered or granular concentrate, such as sodium chloride or sodium bicarbonate. More particular, the invention relates to a device for use in a cartridge of the above-mentioned type, a cartridge provided with such a device, a method of manufacturing such a cartridge and the use of a charge of concentrate in such a cartridge.
[0002] To those skilled in the art, it will be apparent that the present invention can be used in connection with other medical procedures where a fluid suitable for the procedure is obtained from mixing of a solvent (e.g. water) with at least one concentrate in powder form, such as replacement fluids in connection with hemodiafiltration and hemofiltration operations.
BACKGROUND OF THE INVENTION
[0003] Dialysis is a well-known method for treatment of kidney insufficiency. In hemodialysis, the blood of a patient suffering from impaired kidney function is conducted from a patient blood vessel to a dialysis machine and is returned to the patient after the treatment. The blood is conducted along one side of a permeable membrane in a dialyzer or filter connected to the dialysis machine, at the same time as dialysis fluid or dialysate may be conducted along the opposite side of the same membrane. Waste substances or poisons that are to be removed from the blood pass potentially with the help of diffusion from the blood to the dialysis fluid through the membrane. Excess water is also removed from the blood. A hemodialysis treatment typically lasts 3-5 hours. Preferably, a treatment may be performed while the patient is sleeping during night and may in that case last for about 8 hours.
[0004] On-line preparation of dialysis fluid is known. For example, the on-line preparation of a saturated bicarbonate solution from powdered bicarbonate contained in a cartridge is disclosed in DE 198 01 107 A1.
[0005] For the preparation of a dialysis fluid, saturated sodium bicarbonate solution may be mixed with a solution comprising appropriate electrolytes, such as K + , Ca 2+ and Mg 2+ .
[0006] In EP 0 278 100 B1 a powder cartridge is shown. The cartridge comprises a closed vessel provided with penetrable membranes at its upper inlet end and its lower outlet end, respectively. Within the vessel, there is provided a supply of powder concentrate of sufficient quantity so as to be suitable for a dialysis treatment session. For instance, in connection with the preparation of dialysis fluid or solution, the concentrate may consist of powdered sodium chloride or sodium bicarbonate.
[0007] In use, a powder containing prior-art cartridge is first primed with fluid, such as water, either from the top or from the bottom. Enough fluid is introduced into the cartridge during priming so that the fluid level is above the powder level. The powder is dissolved in the fluid and a saturated solution can leave the cartridge through the outlet in the bottom of the cartridge. As the solution leaves the cartridge a corresponding amount of new fluid is introduced into the cartridge. To establish that the degree of saturation of the solution leaving the cartridge is satisfactory, the conductivity of the solution may be measured. An unsatisfactory conductivity (saturation) will trigger an alarm in the dialysis machine.
[0008] The above-mentioned way of on-line preparation of solutions for medical use by means of a powder cartridge has many advantages. There are, however, some disadvantages with prior-art cartridges. After a few hours of use, the mixture of the fluid and the powder in the cartridge may become inhomogeneous. In some instances, clods may be formed. The clods may prevent gas bubbles from rising to the liquid surface. When a bubble is “released”, a channel in the powder bed may be created, sometimes all the way down to the lower outlet of the cartridge. This may allow unsaturated solution to leave the cartridge causing a conductivity alarm. The alarm must be taken care of either by the patient or by a nurse or medical attendant. If these problems occur, they may be remedied by knocking on the cartridge wall or by shaking the cartridge. However, often the cartridge has to be discarded, while still containing a considerable amount of powder, and replaced by a new cartridge.
[0009] The formation of channels in the powder bed might have other causes. For example, the fluid may be introduced gradually through the top inlet and fall in drops down to and impact the liquid surface. This may give rise to pressure waves in the liquid bed which in turn create fluid currents perpendicular to the powder bed surface. These currents may work their way down in the powder bed, creating channels in the bed reaching the lower outlet, making it possible for unsaturated solution to leave the cartridge.
SUMMARY OF THE INVENTION
[0010] In these circumstances it is an object of the present invention to create opportunities for improved on-line preparation of a solution intended for a medical procedure, in particular of sodium chloride or bicarbonate solution for hemodialysis, by means of a powder or granular cartridge. This and other objects are achieved by a device for use in a cartridge, the device comprising the features of the enclosed independent device claim, a cartridge provided with such a device according to the enclosed independent cartridge claim, a method of manufacturing such a cartridge comprising the steps of the enclosed independent method claim, and/or a method of use comprising the features of the enclosed independent use claim. Preferred embodiments are set forth in the enclosed dependent claims and in the following description.
[0011] By arranging a device according to the invention in a powder cartridge for online preparation of a solution, the fluid continuously introduced in the cartridge may be distributed in a desired way so as to minimize the risk of formation of channels and inhomogeneities in the powder bed. In turn this minimizes the risk of unsaturated solution leaving the cartridge. Thus, the chance that the whole amount of powder in the cartridge can be used is increased. This is of course favorable, both as regards operating results and costs.
[0012] Furthermore, during the initial priming of a cartridge, the inventive device provides a more even distribution of the fluid.
[0013] By preferably letting the device being elongated and having the through holes vertically distributed over its elongated wall, it is possible to let the fluid be output below the liquid/air surface also when the liquid level is sinking gradually. Therefore, the fluid does not fall in drops down on the liquid surface. The generation of pressure waves is avoided. Consequently, the formation of channels in the powder bed is minimized.
[0014] The device is preferably conical, which means that it easily can be stuck into the dry powder bed when preparing a cartridge.
[0015] The inventive cartridge exhibits advantages corresponding to those mentioned above as regards the inventive device.
[0016] The manufacturing method according to the invention is simple and cost-effective.
[0017] The use of an inventive cartridge, wherein the solvent is entering the vessel via an inventive device, allows a more efficient use of the powder or granulate and longer periods without operating interruptions. This implies a cost-effective process.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 shows a prior-art cartridge for on-line preparation of a solution.
[0019] FIG. 2 shows a device according to a preferred embodiment of the invention for use in a cartridge.
[0020] FIG. 3 shows an inventive device attached to a cartridge lid.
[0021] FIG. 4 is an isometric cut-away view of an inventive cartridge.
[0022] FIG. 5 and 6 illustrate the principle of the use of an inventive cartridge.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0023] In hemodialysis, the blood of a patient suffering from impaired kidney function is conducted from a patient blood-vessel (of for example the patient forearm) to a dialysis machine and is returned to the patient after the treatment. The blood is conducted along one side of a permeable membrane in a dialyser or filter working with and/or as a part of the dialysis machine. At the same time, a dialysis fluid may be conducted along the opposite side of the same membrane. A transfer of waste substances or poisons and excess water that are to be removed from the blood may take place by the help of diffusion through the membrane from the blood to the dialysis fluid. One dialysis treatment may typically last from about 3 to 8 about hours.
[0024] In FIG. 1 , a prior-art cartridge 1 for on-line preparation of a saturated bicarbonate solution from powdered sodium bicarbonate is shown. For the preparation of a dialysis fluid, the saturated sodium bicarbonate solution may be mixed with a solution comprising appropriate electrolytes, such as K + , Ca 2+ and Mg 2+ . The cartridge 1 may include a closed vessel or container 2 with an upper inlet end 3 and a lower outlet end 4 . Within the vessel 2 , there is provided a supply of powder concentrate 5 of sufficient quantity so as to be suitable for one or more treatments. The quantity of the powder contained in the cartridge would be on the order of magnitude of 400-1500 grams. Sodium chloride is another typical example in dialysis procedures.
[0025] Hereinafter a preferred embodiment of the inventive device for use in a powder or granulate cartridge will be described.
[0026] A device 6 according to the invention is shown in FIG. 2 . The device comprises an elongated, and in some embodiments substantially conical tube 6 made typically of a plastic such as polypropylene. The tube 6 isclosed at its lower end 7 and open at its upper end 8 . In the wall 9 of the tube 6 through holes 10 are provided. This particular embodiment has eight holes 10 arranged in pairs on opposite sides of the tube 6 . Furthermore, the device 6 is provided with a neck portion 11 , which may be provided with engagement means, such as flanges or threads 11 ′. In FIG. 3 , a device 6 attached to a lid 12 of a cartridge is shown. Preferably, the neck portion 11 and the lid 12 are constructed so that the device 6 can be snapped onto the lid 12 . Alternatively, the device 6 and the lid 12 can be made as an integral unit.
[0027] It is appreciated that the inventive device 6 as well as the cartridge 13 (vessel 14 and lid 12 ) (see e.g. FIG. 4 ) can be made of other materials than polypropylene.
[0028] In FIG. 4 , an embodiment of the inventive cartridge is shown. The cartridge 13 may be made of a polypropylene (or other material) vessel or container 14 and a polypropylene (or other material) lid 12 . The lid 12 has a liquid permeable inlet 16 . A solvent, which is to be introduced into the cartridge 13 , may be supplied via a tube 17 . In the bottom end of the vessel 14 a liquid permeable outlet 18 is provided. A tube 19 for discharge of a solution may be connected to the outlet 18 . The tubes 17 and 19 may not necessarily form part of the inventive cartridge. Furthermore, the cartridge 13 has a conical tube 6 as disclosed above (cf. FIG. 2 ) connected at its neck portion 11 to the lid 12 . The embodiment of the device 6 shown in FIG. 4 comprises two elongated flanges or ridges 15 a, 15 b. The ridges 15 a, 15 b are arranged longitudinally along and on the inside of the device 6 . These ridges 15 a, 15 b may act as “fluid guides”. The incoming fluid may then follow the inside wall of the tube 6 or flow along the ridges 15 a, 15 b. The “fluid guides” may alternatively consist of plastic pellets.
[0029] An inventive cartridge may be manufactured according to the following. Reference is made to FIGS. 4 and 5 . A vessel 14 is provided and a batch of powder or granulate 20 is poured into the vessel 14 . A tightly fitting lid 12 is attached to the vessel 14 so that the tube 6 is stuck into the powder bed 20 . The lid 12 may be threaded or may be welded to the vessel 14 . Alternatively, using a self-containing cartridge, the powder may be sucked into the vessel 14 through some kind of membrane.
[0030] In use (see FIGS. 5 and 6 ), first air is sucked from the cartridge 13 for the purpose of creating a vacuum in the cartridge. Then the cartridge is primed with a solvent, such as water, by letting solvent flow into the cartridge at a relatively high flow rate of about 1000 mL/min. It should be noted that the air removal and water priming may occur substantially simultaneously. In FIG. 5 a primed cartridge is shown. The solvent may be introduced either through the upper inlet 16 or the lower outlet 18 , then having dual purpose, i.e. inlet at priming and outlet of saturated solution. In this example, the powder 20 may be sodium bicarbonate, and then the solvent 21 should be present in a sufficient amount so that the liquid level 22 is above the surface 23 of the powder bed 20 . The powder 20 is dissolved in the solvent 21 and a saturated sodium bicarbonate solution may leave the cartridge 13 through the outlet 18 . New solvent 21 is gradually entering the cartridge 13 , at a relatively low flow rate which is less than or about the same as the rate of solution leaving the cartridge and may be of about 15 mL/min. The sodium bicarbonate solution may then be mixed outside the cartridge with a fluid containing electrolytes for yielding a dialysis fluid.
[0031] At least the lower holes of the tube 6 should be situated below the fluid level 22 and the fluid outlets 10 should be “directed” substantially towards the vessel wall so that the outflow of solvent 21 from the tube 6 is directed substantially horizontally, i.e. in parallel with the fluid level 22 , as shown in FIG. 6 .
[0032] The incoming fluid may then be prevented from freely falling in drops down to the fluid surface. The pressure waves and the currents will then be directed towards the wall of the vessel and dampened out before they reach the powder bed 20 . The channeling effect is minimized. Tests have shown that the functioning time before an alarm is triggered can be prolonged as much as two hours compared to when using a prior-art cartridge intended for example for 8 h of use.
[0033] It should be noted that the cartridge 13 may also be formed without a lid, either as a closed vessel or an open vessel (not shown).
[0034] It is easily appreciated that the inventive device can be applied together with other types of cartridges, and the inventive idea for cartridges containing other substances than sodium bicarbonate. It is further appreciated that the inventive idea can be applied for other medical purposes than hemodialysis, such as for replacements fluids for hemodiafiltration and hemofiltration. | The invention provides a device for use in a cartridge for on-line preparation of a solution for a medical procedure. The device comprises a hollow body, the body having a first end and a second end and is provided with through holes in its wall. The second end is closed, while the first end is open and adapted for receiving fluid introduced into the cartridge. The fluid leaves the device through said holes. Furthermore, the invention relates to a cartridge provided with such a device, a method of manufacturing such a cartridge and the use of a charge of concentrate in such a cartridge. | 0 |
[0001] This is a continuation-in-part application of application Ser. No. 12/437,745, filed May 8, 2009, the entirety of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to batteries and more particularly to lithium-ion batteries.
BACKGROUND
[0003] Batteries are a useful source of stored energy that can be incorporated into a number of systems. Rechargeable lithium-ion batteries are attractive energy storage systems for portable electronics and electric and hybrid-electric vehicles because of their high specific energy compared to other electrochemical energy storage devices. In particular, batteries with a form of lithium metal incorporated into the negative electrode afford exceptionally high specific energy (in Wh/kg) and energy density (in Wh/L) compared to batteries with conventional carbonaceous negative electrodes.
[0004] When high-specific-capacity negative electrodes such as lithium are used in a battery, the maximum benefit of the capacity increase over conventional systems is realized when a high-capacity positive electrode active material is also used. Conventional lithium-intercalating oxides (e.g., LiCoO 2 , LiNi 0.8 Co 0.15 Al 0.05 O 2 , Li 1.1 Ni 0.3 Co 0.3 Mn 0.3 O 2 ) are typically limited to a theoretical capacity of ˜280 mAh/g (based on the mass of the lithiated oxide) and a practical capacity of 180 to 250 mAh/g. In comparison, the specific capacity of lithium metal is about 3863 mAh/g. The highest theoretical capacity achievable for a lithium-ion positive electrode is 1168 mAh/g (based on the mass of the lithiated material), which is shared by Li 2 S and Li 2 O 2 . Other high-capacity materials including BiF 3 (303 mAh/g, lithiated) and FeF 3 (712 mAh/g, lithiated) are identified in Amatucci, G. G. and N. Pereira, Fluoride based electrode materials for advanced energy storage devices. Journal of Fluorine Chemistry, 2007. 128(4): p. 243-262. All of the foregoing materials, however, react with lithium at a lower voltage compared to conventional oxide positive electrodes, hence limiting the theoretical specific energy. The theoretical specific energies of the foregoing materials, however, are very high (>800 Wh/kg, compared to a maximum of ˜500 Wh/kg for a cell with lithium negative and conventional oxide positive electrodes).
[0005] Lithium/sulfur (Li/S) batteries are particularly attractive because of the balance between high specific energy (i.e., >350 Wh/kg has been demonstrated), rate capability, and cycle life (>50 cycles). Only lithium/air batteries have a higher theoretical specific energy. Lithium/air batteries, however, have very limited rechargeability and are still considered primary batteries.
[0006] While generally safe, the amount of energy stored within a battery as well as the materials used to manufacture the battery can present safety issues under different scenarios. Safety is particularly an issue when a battery is subjected to increased temperatures either as a result of internal processes or as a result of the environment in which the battery is located.
[0007] By way of example, when batteries are charged or discharged, they typically generate heat due to a finite internal resistance that includes ohmic, mass-transfer, and kinetic terms. Exothermic side reactions can also generate heat within the battery. This heat generation can pose a safety risk if it is large and rapid. For instance, commercial Li-ion cells generally go into thermal runaway if the internal cell temperature climbs above the decomposition temperature of the cathode (˜180 to 220° C., depending upon the chemistry and the state of charge). Often the events that lead to a temperature rise above this critical temperature are triggered at much lower temperatures. For example, exothermic anode film decomposition can occur at ˜120° C., providing enough energy to raise the battery temperature above 180° C. Excessive temperature in a battery may leading to venting of gases, smoke, flames, and, in rare cases, explosion.
[0008] Undesired amounts of heat may also be generated in a battery due to undesired physical changes in the battery. By way of example, formation of an electronically conducting phase between the two electrodes (i.e., internal shorting) of the battery can lead to excessive internal discharge. Internal shorting may be caused by dendrite formation, separator melting, separator cracking, separator tearing, pinholes, or growth of some conductive material through the separator. Thus, in addition to safety concerns, dendrite formation can significantly shorten the lifespan of an electrochemical cell.
[0009] Furthermore, without good control of the uniformity of dissolution and deposition of the electrode material, morphology changes unrelated to dendrite formation may occur during cycling of the cell. These morphology changes can lead to changes in electrode surface area and subsequent reaction with the electrolyte and/or deleterious volume changes in the cell, either of which can result in capacity fade and impedance rise in the cell.
[0010] What is needed therefore is a battery that is less susceptible to dendrite formation and other undesired morphology changes.
SUMMARY
[0011] In accordance with one embodiment, an electrochemical cell includes a negative electrode including a form of lithium, a positive electrode spaced apart from the negative electrode, a separator positioned between the negative electrode and the positive electrode, and an electrolyte including a load leveling agent in contact with the negative electrode.
[0012] In accordance with another embodiment, an electrochemical cell includes a negative electrode including a form of lithium, a positive electrode spaced apart from the negative electrode, a separator positioned between the negative electrode and the positive electrode; and an electrolyte including a load leveling agent in contact with the negative electrode and with the positive electrode.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 depicts a schematic of an electrochemical cell with one electrode including a form of lithium and another electrode including an active material with a form of lithium.
DESCRIPTION
[0014] For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and described in the following written specification. It is understood that no limitation to the scope of the invention is thereby intended. It is further understood that the present invention includes any alterations and modifications to the illustrated embodiments and includes further applications of the principles of the invention as would normally occur to one skilled in the art to which this invention pertains.
[0015] FIG. 1 depicts a lithium-ion cell 100 , which includes a negative electrode 102 , a positive electrode 104 , and a separator region 106 between the negative electrode 102 and the positive electrode 104 . The negative electrode 102 , positive electrode 104 , and separator region 106 are contained within a pouch 108 . The negative electrode 102 includes an active material plate 110 which includes active material into which lithium can be inserted along with inert materials, and a current collector 116 .
[0016] The negative electrode 102 may be provided in various alternative forms. The negative electrode 102 may incorporate dense Li metal or a Li metal alloy. Incorporation of Li metal is desired since the Li metal affords a higher specific energy than graphite.
[0017] The separator region 106 includes an electrolyte 114 with a lithium cation and serves as a physical and electrical barrier between the negative electrode 102 and the positive electrode 104 so that the electrodes are not electronically connected within the cell 100 while allowing transfer of lithium ions between the negative electrode 102 and the positive electrode 104 .
[0018] The positive electrode 104 includes active material 120 into which lithium can be inserted, inert materials 124 , the electrolyte 114 and a current collector 126 . The active material 120 may include a form of sulfur and may be entirely sulfur. The active material 120 may incorporate a form of lithium such as lithium oxide or Li 4+x Ti 5 O 12 .
[0019] The lithium-ion cell 100 operates in a manner similar to the lithium-ion battery cell disclosed in U.S. patent application Ser. No. 11/477,404, filed on Jun. 28, 2006, the contents of which are herein incorporated in their entirety by reference. In general, electrons are generated at the negative electrode 102 during discharging and an equal amount of electrons are consumed at the positive electrode 104 as lithium and electrons move in the direction of the arrow 130 of FIG. 1 .
[0020] In the ideal discharging of the cell 100 , the electrons are generated at the negative electrode 102 because there is extraction via oxidation of lithium ions from the active material 110 of the negative electrode 102 , and the electrons are consumed at the positive electrode 104 because there is reduction of lithium ions into the active material 120 of the positive electrode 104 . During discharging, the reactions are reversed, with lithium and electrons moving in the direction of the arrow 132 .
[0021] The electrolyte 114 of FIG. 1 , however, further includes a load leveling additive. A load leveling material, such as the load leveling materials identified in U.S. Patent Publication No. 2004/0242804, published on Dec. 2, 2004, the entire contents of which are incorporated herein by reference, is preferably a high molecular weight material and/or provided in a low concentration, thus resulting in bulk diffusion controlled adsorption onto the surface of the depositing anode. The inclusion of a load leveling material in the electrolyte 114 reduces the potential for formation of dendrites.
[0022] As discussed in Roha, D. and U. Landau, Mass Transport of Leveling Agents in Plating: Steady-State Model for Blocking Additives. Journal of The Electrochemical Society, 1990. 137: p. 824, the exact mechanism by which load levelers encourage uniform deposition of ions is not fully understood. Nonetheless, the load leveling material encourages uniform uptake of lithium by the negative electrode 102 even if the negative electrode 102 includes surface defects. Thus, uneven deposition, which encourages dendrite production, is reduced. Optimal concentrations of load leveling agents for particular battery chemistries may be determined using the model provided by Roha et al.
[0023] While the invention has been illustrated and described in detail in the drawings and foregoing description, the same should be considered as illustrative and not restrictive in character. It is understood that only the preferred embodiments have been presented and that all changes, modifications and further applications that come within the spirit of the invention are desired to be protected. | An electrochemical cell in one embodiment includes a negative electrode including a form of lithium, a positive electrode spaced apart from the negative electrode, a separator positioned between the negative electrode and the positive electrode, and an electrolyte including a load leveling agent in contact with the negative electrode. | 8 |
BACKGROUND OF THE INVENTION
The invention relates to novel textile lubricating oil compositions, to a process for treating or oiling textile fibers using such compositions and with the treated or oiled textile fibers so prepared.
Lubricating oils have been used in the processing of textile fibers for many years. Usually the lubricating oils are mineral oils but there is an increasing tendency to replace such oils by synthetic oils.
One textile process in which lubricating oils have been applied is the winding of yarns, e.g. continuous filament yarns onto cones. Such cones are then used in knitting processes. In such processes the yarn is wound at high speeds, e.g. from 300 to 1,000 meters/minute, onto the cone. Before being wound the yarn passes over a roller, usually described as a lick roller, which is partly immersed in a bath of the lubricating oil, by which means the yarn becomes lubricated or oiled. The lubricating oils used in this process are sometimes described as coning oils or knitting oils and the process is sometimes described as coning. Further information on coning oils may be obtained from the Book of Papers for the 13th Canadian Textile Seminar, 1972, pages 68 to 73.
Coning oils should preferably have the following characteristics. They should be good lubricants i.e. produce low yarn/yarn and yarn/yarn guide (metal, ceramic) friction; they should be water-soluble or emulsifiable in order that they may be scoured or washed from the final textile articles and they should be non-corrosive, non-toxic, biodegradable and physically and chemically stable. A further desirable characteristic which is now receiving increasing attention is that they should be non-splashing or non-slinging. Splashing or slinging is a phenomenon observed during the high speed winding of yarns which results in oil droplets being "slung" off the yarns immediately after they loose contact with the lubricating rollers. Such oil droplets fall onto the winding machine and the flow which, apart from resulting in a loss of oil, endangers the operators and increases costs as a result of the necessary cleaning operation.
SUMMARY OF THE INVENTION
I have now discovered a lubricating composition which has the desirable characteristics required for a coning oil. In particular the lubricating oil compositions of the present invention are substantially non-splashing and are water-soluble.
According to this aspect of the present invention a lubricating oil comprises a major proportion of an ether of formula:
R--O --C.sub.m H.sub.2m --O--.sub.x H
wherein
R is a C 1 to C 10 alkyl group,
m is an integer of from 2 to 4, and
x is an integer of from 2 to 20;
And a minor proportion of a polymer of an ethylenically unsaturated carboxylic acid.
According to another aspect of the present invention a process for treating or oiling textile fiber comprises contacting the textile fibers with a lubricating oil composition as described herein.
DESCRIPTION OF PREFERRED EMBODIMENTS
Although the lubricating oil compositions may be used in various textile processes, for example carding and spinning processes, they are particularly useful in coning processes. According to this preferred aspect of the present invention the textile fibers are contacted with the composition during the winding thereof onto cones. For example the textile fibers or yarns are wound onto cones by passing the fibers or yarns over a roller which is partly immersed in a lubricating oil composition. Alternatively the composition may be applied to the fibers or yarns during the winding thereof onto cones by nozzle-type applicators. Before the yarn is treated with the coning oil it is conventional practice to apply a texturizing treatment to improve the bulk thereof. The yarn is suitably in the form of continuous filaments and the process is particularly suitable for treating texturized continuous filament yarns of synthetic material such as polyester or nylon. Usually the amount of lubricating oil composition picked up by the yarn is between 2 and 5%w based on the weight of the yarn.
The lubricating oil components of the compositions of the present invention are suitably prepared by reacting one or more C 1 to C 10 alcohols, or a C 2 to C 4 alkoxylate thereof, with one or more C 2 to C 4 alkylene oxides i.e. ethylene oxide, propylene oxide or butylene oxide or mixtures thereof. Preferred components are those derived from C 1 to C 4 alcohols, i.e. compounds of the above formula wherein R is C 1 to C 4 , and particularly those derived from methanol, ethanol or mixtures thereof. Preferred components are those derived from ethylene oxide, i.e. compounds of the above formula wherein m is 2. Preferably the amount of C 2 to C 4 alkylene oxide is such that x has an average value of from 2.5 to 10, more preferably of from 3 to 8. Usually the alkoxylation product is a mixture of different chain length alkoxylates which may be separated into various fractions if desired.
An anti-splashing agent is also present in the compositions of the present invention. It should be pointed out that the function of the anti-splashing agent is not to thicken the lubricating oil but to impart to the oil the property of stringyness or pituituosness. This property prevents oil droplets being slung off the yarn during the oiling or coning process.
As stated hereinbefore the anti-splashing agent is a polymer of an ethylenically unsaturated carboxylic acid. Such polymers may be those derived from one or more ethylenically unsaturated monocarboxylic acids such as acrylic acid, methacryic acid i.e. acids having the general formula:
C.sub.n H.sub.2n-1 COOH,
and/or one or more ethylenically unsaturated dicarboxylic acids such as fumaric acid or maleic acid i.e. acids having the general formula:
C.sub.n H.sub.2n-2 (COOH).sub.2
wherein, in both formulae, n is a whole number of from 2 to 10, preferably of from 2 to 6.
The aforesaid polymers may be homopolymers or copolymers i.e. polymers of an ethylenically unsaturated carboxylic acid and one or more different monomers. Examples of different monomers include unsaturated monomers such as ethers e.g. C 1 to C 4 vinyl ethers, esters e.g. C 1 to C 4 esters of acrylic acid or methacrylic acid, amides e.g. acrylic acid amides, salts e.g. acrylic acid salts, and olefins e.g. ethylene. The only restriction on the type of monomers used is that the polymer should be sufficiently soluble in the lubricating oil component. The preferred comonomers are esters, in particular C 1 to C 4 (meth)acrylic esters and/or C 1 to C 4 vinyl ethers.
The polymers may be prepared directly i.e. by polymerizing an ethylenically unsaturated carboxylic acid, optionally in the presence of other monomers, or indirectly i.e. by polymerizing an ethylenically unsaturated carboxylic acid group precursor, e.g. maleic anhydride, again optionally in the presence of other monomers, followed by conversion of the carboxylic acid group precursor, e.g. by hydrolysis, into carboxylic acid groups. This conversion may take place before or after the polymer is added to the lubricating oil component.
Suitable polymers are those having an average molecular weight between about 4 × 10 4 and about 2 × 10 7 .
Suitable polymers are copolymers of maleic acid and a C 1 to C 4 vinyl ether and may be represented by the following formula: ##STR1## wherein R is a C 1 to C 4 alkyl group, preferably methyl, and p is an integer. Such polymers may be added to the lubricating oil component in the form of its anhydride which is then hydrolyzed, at least partially, e.g. by adding an alkali-metal hydroxide. Consequently, most of the anhydride groups will be converted to acid groups and some of the acid groups may be in the form of carboxylic acid salt groups. Polymers of these types are commercially available under the trade name GANTREZ (ex GAF). Specific examples include GANTREZ AN 169 and GANTREZ HY-H.
Other suitable polymers consist mainly of the recurring unit of the formulae: ##STR2## wherein R 1 is H or methyl, R 2 is a carboxylic amide or ester group, and p and q are integers. At least some of the acid groups may be present as carboxylic acid salt e.g. sodium groups. Preferred polymers of this type are polyacrylic acid or polymethacrylic acid or copolymers of acrylic or methacrylic acids with a C 1 to C 4 ester of acrylic or methacrylic acid. Polymers of these types are commercially available under the trade name ROHAGIT (Ex Rohm & Haas) and VISCALEX (ex Allied Chemicals). Specific examples include ROHAGIT S, NV, MV or HV and VISCALEX EM 15.
The aforesaid anti-splashing agents may be added to the lubricating oil in the form of powders, aqueous emulsions, solutions or gels. Suitably the amount of anti-splashing agent added is from 0.01 to 5%w, preferably from 0.05 to 2.5%w, based on the weight of the ether. Other additives may be present in the lubricating oil compositions. Additional additives include water, which may be necessary if clear solutions are desired, in amounts of from 1.0 to 25%w, based on the weight of the lubricating oil composition; corrosion inhibitors, e.g. sodium benzoate, sodium salicylate, a salt of n-C 12 /C 14 -beta-propionic acid, a lauroylsarcosine, or a mono- or polyalkyl phosphate, phosphite of phosphonate in amounts of from 0.05 to 1.5%w, based on the weight of the lubricating oil composition; and/or anti-oxidants e.g. phenolic compounds such as di-tert-butyl cresol, diphenylolpropane and alkylated diphenylolpropanes which antioxidants are typically applied in amounts of from 100 to 10,000 ppm. An alkaline compound, e.g. sodium hydroxide or potassium hydroxide, may also be added to increase the pH of the composition. In this case some of the acid groups of polymer may be in the form of carboxylic acid salt groups.
The invention will not be illustrated by reference to the following Examples.
EXAMPLES 1 TO 4
The lubricating oil used in these examples was a methanol ethyoxylate containing an average of 3.5 moles of ethylene oxide for each mole of methanol.
The types of anti-splashing agents used were: (1) A polymethacrylic acid. It is characterized in that a 3%w solution in water, after addition of sodium hydroxide to produce a pH of 9-10, has a viscosity in the range of from 7700-11000 centipoise (cP) (Brookfield-Viscosimeter, Spindle III, 6 rpm at 20° C.). (2) A copolymer of acrylic acid and the methyl ester of acrylic acid (about 1:1 mole). It is characterized in that a 1%w solution in water, after addition of sodium hydroxide to produce a pH of 7, has a viscosity of in the range of from 350-550 centistokes (cSt) (suspended level viscosimeter). (3) A poly(methylvinylether/maleic anhydride). It is characterized in that it has a specific viscosity of 2.6-3.5 (measured as 1g in 100 ml of methyl ethyl ketone of 25° C.). (4) A poly(methylvinylether/maleic acid). It is characterized in that a 1%w solution in water, after addition of sodium hydroxide to produce a pH of 7, has a viscosity of 175 cSt at 20° C. (suspended level viscosimeter).
Various lubricating oil compositions were prepared and details thereof are given in Table 1. The compositions were prepared by adding the anti-splashing agent and small amounts of water to the lubricating oil component and heating the mixture until a clear solution was obtained. In the case of Examples 3 and 4, 0.16%w and 0.28%w respectively of sodium hydroxide were added to the compositions.
The lubricating oil compositions were tested as coning oils by winding texturized continuous filament yarns of polyesters onto cones at a winding speed of 350 meters per minute.
The equipment used was conventional and included a steel lick roller, partly immersed in a bath of lubricating oil composition, over which the yarns passed before being would onto cones. Sheets of absorbant paper were positioned around the equipment and the number of splashes of lubricating oil composition found on the absorbant paper after 10 minutes of winding were counted. In addition the %w of coning oil composition picked up by the filaments was also determined.
The coefficients of yarn/steel friction were also determined at a winding speed of 100 meters/minute according to ASTM D 3108 (using a steel friction pin of 8 mm diameter, an angle of wrap of 180° and a measuring time of 10 minutes).
For comparative purpose the lubricating oil without the addition of an anti-splashing agent was also treated and results are reported in Table I as (a) and (b). Also for comparison a commercial mineral oil lubricating composition was also tested and results are reported in Table I as Example (c).
Table 1__________________________________________________________________________Anti-splashing Agent pH of 5%w coefficient of Amount aqueous Added water.sup.1 oil picked up number of splashed yarn/steel frictionExampleType (%w) solution (%w) by yarn (%w) oil droplets (100 m/min)__________________________________________________________________________a -- -- 5.1 -- 3.2 196 0.25b -- -- 5.1 10 2.58 341 0.261 1 0.5 5.3 2.5 3.5 0 0.252 2 0.2 5.0 10 3.5 0 0.243 3 1.0 4.3 10 3.5 0 0.244 4 0.5 5.1 10 3.5 0 0.25c -- -- 5.32 -- 3.37 297 0.25__________________________________________________________________________ 1. Amount required to obtain clear solution except for example b where water has been added for comparative purposes. 2. 5 %w of emulsion of oil in water.
EXAMPLE 5
Knitted articles of polyester were dyed under pressure at a temperature of 130° C. in an aqueous bath containing 2.4%w of a blue dye (Terasil Dark Blue RB) and 3.6%w of a pink dye (Terasil Brilliant Pink EG) on knitted articles. The knitted articles were prepared from yarns treated with the composition of Examples 2 and c. The %weight of oil on the knitted fibers before and after dyeing was determined. The results are shown in Table II.
Table II______________________________________ Oil on article (%w)Example Composition before dyeing after dyeing______________________________________5 Example 2 3.9 0.08d Example c 4.0 0.18______________________________________
EXAMPLES 6 TO 9
Examples 2 to 4 were repeated using an ethanol ethoxylate containing an average of 3.5 moles ethylene oxide for each mole of ethanol and 15%w of water. The compositions had a pH (5%w aqueous solutions) of from 5 to 6. Substantially the same results were obtained.
EXAMPLES 10 TO 13
Examples 2 to 4 were repeated using a methanol ethyoxylate containing an average of 5 moles of ethylene oxide for each mole of methanol and 15%w of water. The compositions had a pH (5%w aqueous solutions) of from 5 to 6. Substantially the same results were obtained. | Textile fiber lubricants are disclosed comprising a major amount of (1) the reaction product of (a) at least one C 1 to C 10 alcohol, or (b) at least one C 2 to C 4 alkylene oxide with (c) at least one C 2 to C 4 alkylene oxide, and a minor amount of a polymer of an ethylenically unsaturated carboxylic acid. | 3 |
BACKGROUND OF THE INVENTION
The invention relates to a hob with cutting plates for making gears.
A hob is known (DE-OS No. 2 700 525), wherein the known cutting plates, which consist of hard metal, are distributed helix-like on disk-like gear rims which are provided with plane parallel front faces. Thereby, it is possible that the plate seats can be made by means of milling, so that the total tool does not have to be replaced when individual plate seats wear out, but that only individual parts have to be replaced. However, a disadvantage of the known device is that no diplacement of the individual teeth with respect to each other is possible, due to the even design of the disk-like gear rim. However, a twist like displacement of the teeth is advantageous, because a more favorable cutting ratio is obtained during the operation of the hob and also cuts more evenly if not a few or a plurality of teeth are engaged, but rather sequentially, whereby a time delay is obtained caused by the dimension of the displacement or the dimension of the twist angle γ. Basically, it is possible to provide a displacement for the sequentially engaging teeth when using disk like tooth rims which are provided with reversible cutting plates on their teeth. However, a prerequisite would be that the individual disks are not even, so that the manufacturing costs for such a hob and also the storage costs for the replacement parts would be considerably increased. In addition, the life span of the plate seats for receiving the cutting plates are different, because the tooth stresses within the engagement area are different, in particular during the rough hob milling into the full material. This can be taken into consideration in the known device by exchanging a complete disk like gear rim with another. However, this requires that the hob must be dismantled from the hob machine and must be dismantled into its individual components.
In addition, these known milling devices are only single threaded.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a hob, wherein individual components with only a few teeth can be exchanged with even teeth segments in case of wear or a damage to the plate seat which receive the reversible plates, without replacing a complete gear disk of 360°, and without requiring a removal of the hob for the hob machine. In addition, it should be possible to provide a hob with twist-like displaced teeth by using even exchangeable parts.
As a solution, the invention provides that a plurality of helix-like tooth segments are provided in the milling element and are mounted in a thread-like guide of the milling element. Preferably, the tooth segments are mounted in a twist like displacement of the cutters with respect to the axis parallel directrix, whereby the individual tooth segments may be even, so that they can be exchanged against each other or with each other. This design has the advantage that individual tooth segments can be exchanged at any given location of the milling element in case of wear of one or a plurality of plate seats, without requiring a dismantling of the milling element or by completely dismantling it into its individual components. A further advantage is that when making the individual tooth segments, the plate seats are easily accessible. Therefore, short and sturdy tools may be used, so that a plate seat working is made very economical. The structure is also suitable for making a plurality of thread hobs, in contrast to the single disk known from the known device.
One exemplified embodiment of the invention is explained in the following in conjunction with a drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial perspective view of the hob according to the invention;
FIG. 2 is a partial front view of the hob;
FIG. 3 is a partial longitudinal section through the hob;
FIG. 4 is a partial plan view of the hob;
FIG. 5 is a partial cross section through a tooth segment;
FIG. 6 a three thread milling base element in a perspective view; and
FIG. 7 is a section through a tooth segment with two rows of teeth for a two thread milling device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The hob illustrated in the drawing is provided with a milling element 1 which supports a plurality of helix like tooth segments 2,2'. The tooth segments 2,2' each support 4 teeth 3,3' which have a tooth pitch angle α FIG. 2. In the illustrated embodiment the segment angle β is 81° in accordance with FIG. 2.
The individual teeth 3,3' are provided with chambers 4 which serve to receive reversible plates 5. The reversible plates 5 consist of hard metal such as Wolfram carbide, Titanium carbide and are exchangeably inserted in the chambers 4 which serve as plate seats. Of the individual teeth of a tooth segment 2 or 2', the one tooth 3 and 3' supports each two reversible plates 5 which are offset with each other in a heightwise manner and are alternately positioned with respect to the adjacent tooth 3'. In contrast thereto, the teeth 3" and 3'" support only one each reversible plate 5 on the opposite sides, as shown in FIG. 2, in particular at the right portion.
The mounting of the tooth segments 2,2' on the milling element 1 is carried out by radially extending screws 6, whereby always two screws are provided for mounting a tooth segment 2 or 2'. In addition, the mounting of the tooth segments 2 in the embodiment of FIG. 3 is carried out by helix like guide ribs 7 of the milling element 1 which support the tooth segments 2 at their outer faces. In a deviating embodiment in accordance with FIG. 5, the individual tooth segments are provided with a centered helix like guide groove 8 at their bottom, into which a helix like guide rib 9 of the milling element engages. In both embodiments, the possibility exists to remove a tooth segment 2 radially from milling element 1, after removing a screw 6, without dismantling the hob or without removing it from the hob machine.
If a segment angle β is chosen, taking into consideration the equation
β=n×α(1±tan×λ tan γ)
wherein n corresponds to the number of teeth of a segment, one obtains a teeth displacement in accordance with FIG. 4 wherein the hob pitch angle λ is entered, as well as the twist angle γ, when using teeth segments in accordance with FIG. 2. From the drawing it can be seen that the milling screw in accordance with FIGS. 1,3 is single threaded and corresponds to the calculated hob pitch H. Due to the suitable determining of the segment angle β, the head cutters of adjacent gears of the hob engage sequentially in a twist-like manner, as can be seen particularly in FIGS. 1 and 4. Thereby, a stable running is favored during the cutting operation, also when using even tooth segments 2. In addition, the plate seats or chambers 4 are easily accessible for receiving the reversible plates 5, so that a particular economical after working is made possible.
The work piece to be worked is designated with the numeral reference 10 in FIG. 3, wherein it is clearly seen how far the reversible plates 5 extend beyond the teeth 3 of a tooth segment 2, so as to make the reference profile 11 of the workpiece 10 to be milled, as shown in the dash-dotted lines.
Instead of a base element with a plurality of threads 9 in accordance with FIG. 6, tooth segments may be provided with more than one row of teeth, so that a multiple thread hob is provided in accordance with FIG. 7.
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of hobs with cutting plates differing from the types described above.
While the invention has been illustrated and described as embodied in a hob with cutting plates, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention. | A hob for making gears comprises a cylindrical mill base and a plurality of helix-like tooth segments positioned on the surface of the mill base adjacent to each other and each having a number of tooth cutters with cutting plates of hard metal. Tooth segments may be interchangeable if they are worn out. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to a doorway system that allows the use of taller than standard size glass doors and a novel form of header that is used to hold glass doors and sidelight panels in an entranceway. More specifically, the invention relates to glass doors and sidelight panels of a designer's choice of size that are made of glass, or similar materials, and that can be easily erected, inside or outside a building and which allow the doors to be easily moved if repairs are needed.
Architects and building designers are making more and more use of glass doors and sidelights when creating modern buildings. Current design methods attempt to use tall glass doors and sidelights, such as ones that reach from the floor to a twelve-foot high ceiling. Up until the present invention, designers have tended to avoid using glass doors that are taller than the standard eight foot height because of the special construction techniques, and need for 3/4 inch glass to provide door stiffness, and hence, extra expense, that would be required. Once the height of a 1/2 inch thick glass door becomes higher than eight feet, the weight, deflection and physical size of the door become factors that require special consideration in the areas of installation of the door and of making repairs to the closer mechanism or other areas around the door once it has been installed. It is desirable to use 1/2 inch thick glass because it can be tinted, such as with a bronze or gray color.
Tempered glass of 1/2 inch thickness weighs approximately 6.56 pounds per square foot and standard doors, of approximately eight foot height by three foot width, weigh about 160 pounds (plus the weight of the hardware used to attach the door). This weight is almost doubled, to about 315 pounds (plus hardware weight), if the door is twelve feet high by four feet wide, and that makes it heavier for the installers to handle and much more awkward to move around during installation. In addition, as the height of the door increases above eight feet, door deflection increases with wind load. Patch fittings that attach the door and transom glass to the sidelight put more strain on the sidelight, thus the sidelights have to be made thicker or glass fins (both of which increase the cost) added to prevent massive deflection of the sidelight under wind-load. Outdoor wind-load design requirements around the United States average 20 pounds per square foot of force and indoor wind-load design requirements average 5 pounds per square foot of force. While the deflection that results from this required wind-load is not necessarily a safety problem, it is an aesthetic problem that detracts from the building's appearance.
It is also known that office building doors use hydraulic door closer mechanisms, such as those made by the Dorma Rixxon and Door-o-Matic Companies, that sit in the floor at the corner of the doorsill to control closing movement of the door. These mechanisms are typically enclosed in a box under the surface of the floor and have only a spindle projecting upward through the door threshold adjacent the door frame. With standard doors, this spindle will bear all of the door weight and it is necessary for the work crew to align the door with the doorway framework at the construction site so that the vertical edge is correctly set over the spindle.
Also, with standard hardware and construction techniques, it is very difficult to make repairs to the door closer mechanism once a tall door is erected over it. Two more factors now become important: how strong are the side panels and transom, for they have to bear the weight of the heavier than normal door, and how strong is the closer mechanism, because it must restrict the closing movement of the heavy door. With the current methods and doorway structure, if any repairs to the closer mechanism become necessary, the complete door must be removed, not just slid back from the edge of the closer and this entails a large amount of effort.
SUMMARY OF THE INVENTION
A novel apparatus for a doorway system and method for installation thereof wherein glass door panels of a multitute of different heights but of a standard thickness are controlled against tension and deflection and door-opening and -closing forces is disclosed. The doorway system employs a rotatable, force-directing and force-transferring spindle-mechanism at the base that bears all weight of the tall glass door, a rotatable tube to tightly hold glass door panels, a pivoting and rotatable spindle and housing to provide regulation forces and a header that is pre-cut with a longitudinally extending slot therein to sealingly contain either, or both, of door panels or sidelight panels adjacent thereto. The doorway system may be used for either interior or exterior doors, in conjunction with standard door closure mechanisms, and is easily installed, maintained and repaired with the use of a slidable, hinged sled that provides sufficient clearance, in cooperation with the bottom spindle-mechanism, to adjust the position of the bottom of the tube, away from the closer mechanism while leaving the top joined to the header and thereby transfer the weight of the door away from said mechanism. The header is advantageously employed, either with tall glass doors or with standard doors, to simplify installation and to increase the flexibility of door position or the position of the sidelights.
OBJECTS OF THE INVENTION
It is therefore an object of the present invention to provide for the use of very tall glass doors at the entranceway to a building.
It is further object of the present invention to provide for the use of very tall glass doors at the entranceway to a building that can be attached to standard door closer mechanisms.
It is a still further object of the present invention to provide a modular header for doorways that can be pre-cut to specified dimensions and assembled at the building.
These and other objects and advantages of the present invention will be readily apparent to those skilled in the art by reading the following brief description of the drawings, detailed description of the preferred embodiment and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a perspective view of the doorway system of the present invention as it looks installed on a building;
FIG. 2 shows an expanded perspective view of the top of the doorway system;
FIG. 3 shows a cross-sectional view of the top of the doorway, in its natural state, taken along lines III--III of FIG. 2;
FIG. 4 shows a cross-sectional view of the top of the doorway, in its natural state, taken along lines IV--IV of FIG. 2;
FIG. 5 shows an expanding fragmentary perspective view of the bottom of one corner of the doorway showing the lower operative parts of the door mechanism;
FIG. 6 shows a fragmentary elevational view of the lower operative parts of the door mechanism;
FIG. 7 shows a cross-sectional view of the lower operative parts of the door mechanism taken along lines VII--VII of FIG. 6;
FIG. 8 shows a cross-sectional view of the closer spindle of the door mechanism taken along lines VIII--VIII of FIG. 6;
FIG. 9 shows a fragmentary perspective view of a door employing the current invention being fitted (as shown by the arrow) over the bearing housing;
FIG. 10 shows an expanded fragmentary perspective view of the top of one corner of the doorway showing the upper operative parts of the door mechanism and the header that is used at the ceiling to attach doors to the building;
FIG. 11 shows a fragmentary elevational view of the header and the operative parts at the top corner of the doorway;
FIG. 12 shows a cross-sectional view of the pivotable spindle of the top of the doorway taken along lines XII--XII of FIG. 11;
FIG. 13 shows a cross-sectional side view of the pivoting mechanism of the doorway taken along lines XIII--XIII of FIG. 11; and
FIG. 14 shows a cross-sectional sideview of the header taken along lines XIV--XIV of FIG. 11.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The instant invention provides a solution to the above-identified problems and can be used in or on, among other places, tall office buildings 20 such as shown in fragmentary perspective view in FIG. 1. Building 20 has a floor 22, opposite side walls 24 a, b and a front face 26 that can also be a ceiling. FIG. 1 shows that the doorway system 27, according to the present invention, has glass doors 28 a, b held by tubular extrusions 33 a, b respectively, (made by using known methods) which rotate between modular header 35 and floor 22, header 35 being affixed to face 26, as will be explained. The image of a proportionately-sized person 37 walking out of doorway 27 is shown in phantom through one of the glass panels 29 a, b and c that are also held in place between header 35 and floor 22.
FIG. 2 shows an expanded, perspective view of the header 35 with various components ready to be installed. FIG. 3 shows a cross-sectional view taken along lines III--III of header 35 in its natural state and FIG. 4 shows a cross-sectional view taken along lines IV--IV of header 35 in its natural state. Header 35 is in the shape of an inverted "U", with several projections extending into the slot down the middle as will be explained. The required length of a section of header 35 can be measured and pre-cut before shipping to the building site for a given installation of doors or sidelight panels, or combination of the two. Header 35 can be attached to the surface of a ceiling (not shown in FIG. 2) or installed in a ceiling 38, such as shown in FIGS. 3 and 4, with nails or screws 39. Header 35 has opposing sidewalls 41a,b (shown in FIGS. 2 and 3) connected by central section 42. A projection 43a,b extends at approximately 90° from each sidewall to form an opening, or track, 44 adjacent section 42. A pair of right-angle, or "L" shaped projections 45a,b and 46a,b also extend out from sidewalls 41a,b, to form a pair of opposing pockets 47a,b (see FIG. 4).
Depending upon the configuration of sidelight panels or doors to be installed at the building, additional components, such as glazing beads 49 or doorway fillers 53, are also pre-cut to be ready for installation. Wherever a door 28 (not shown in FIG. 2) is to be installed, slidable T-nuts 55a,b are set into track 44 at pre-determined locations and an adjustable pivot housing 58 or a doorstop housing 59 are attached thereto, as with fasteners 60. A doorstop bracket 62 is fixed onto housing 59 and door fillers 53 are set into the space above the doors between housings 58 and 59 so that ends 61a,b are forced into track 44 (as seen in FIG. 4). If a sidelight panel 29 (only partially shown in FIG. 3) is to be installed, glazing beads 49a,b are forced into pockets 47a,b to firmly hold panel 29 in place.
FIG. 5 shows an expanded fragmentary perspective view of the bottom of one corner of the doorway showing the lower operative parts of the door mechanism 70, captured inside of the lower end of extrusions 33, to operate one of doors 28 after a removable sled 150 (not shown in FIG. 5) has been taken away. Mechanism 70 can operate with standard hydraulic door closers 73, that are fitted with a square, or other shape, socket 75 and that are set into foundation 77. Foundation 77 is a rectangular-shaped, boxlike steel cement case that has a removable cover plate 78 attached, as at 79, with a flange 81 securely surrounding an aperture therethrough that is aligned with socket 75. In normal situations, closer 73 is attached to coverplate 78 and the combination then attached to foundation 77; however, this series of attachments could be reversed if necessary.
A spindle 84 with a key 85 is screwed into socket 75 to turn with part 86 of closer 73. If desired, socket 75 can be replaced with a male part, and spindle 84 made with the properly fitted socket (not shown). A circular bearing 88 is set over a bearing retainer 89 which is affixed to flange 81 and a cover 91 placed thereover. Spindle 84 extends from socket 75 up through cover 91 a pre-determined distance. Mechanism 70 has been designed so that all of the weight of the combination of door 28a and extrusion 33a are carried by bearing 88.
An adjustable engagement bracket assembly 100 with a retractable spindle grip 105a,b fits over spindle 84 and grip 105b has a slot 107, of equal width and depth as the same dimensions of key 85, that matingly fits over key 85 for a purpose, as will be described. Assembly 100 is connected to a disc-like engagement bracket flange 110 and has a pair of screw flanges 112a,b projecting orthogonally from opposite sides thereof and flange 110 along opposite radials from one another. Screw flanges 112 a, b are conveniently used to make slight, or fine, adjustments to the relation of the door in the doorway. The bottom end of tubular extrusion 33a has an inner diameter large enough to fittingly surround assembly 100 so that screws 114a,b (not shown in FIG. 5) securely bind extrusion 33a, via apertures 113a,b, to screw flanges 112a,b and spindle grip 105a can be accessed through clearance slot 117, as will be explained.
As seen in FIG. 6, a fragmentary elevational view of the operative parts of the bottom of extrusion 33a, spindle grip 105a is threadingly engaged inside of grip 105b. Turning grip 105a in one direction causes grip 105b to be lowered so that slot 107 mates with key 85 and turning it in the opposite direction causes it to be raised up a sufficient distance to clear key 85. Bracket flange 110 rests upon cover 91 and holds all of the weight of extrusion 33a and glass panel 28a so that floor closer 73 does not bear any weight at all and is only responsible for providing rotational motion through a vertical axis (not shown) that extends up from socket 75. As door 28a and extrusion 33a rotate, a pin guide 120 prevents grip 105 from rotating.
FIG. 10 shows an expanded fragmentary perspective view of the top end of extrusion 33a and showing tube covers 34a,b as they form a shell around extrusion 33a. Extrusion 33a conveniently has slots 36a,b down the entire length, each of which can securely grip a panel, such as 28a. FIG. 11 shows a fragmentary elevational view of the header and the operative parts at the top corner of the doorway. The top of the doorway employs a device very similar to the bottom in that upper pivot housing 135 with a retractable pivot 134 threadedly set therein and a pivot block 136 are rotatingly and pivotally inserted into housing 58 and a bolt 133, accessed through slot 138, can be turned to raise or lower pivot 134 which is connected thereto by intermediate segment 137. Extrusion 33a, which can conveniently be made with different longitudinal configurations, and pivot flange 131 surrounding pivot 134 are initially slipped into the recess 139 in housing 58 with the use of horseshoe-shaped collar 141. A pair of screws 143a,b are used to initially secure collar 141 and pivot 134 inside housing 58 and pivot 134 then self-centers therein. A slightly larger size opening in the ceiling 38 (see FIG. 12) allows the sides 41a,b of header 35 to deform as pivot 134 rocks back and forth.
FIG. 9 shows a fragmentary perspective view of the bottom corner of a door that employs the current invention being erected (as shown by the arrow). A sled 150 having a substantially U-shaped front section 151a hingedly joined as at hinge 152, to rear section 151b is used to slide the bottom of extrusion 33a over cover 91, and then removed. Spindle 105a is turned until slot 107 fits over key 85. As mentioned, collar 141 is fitted around pivot flange 131 and pushed into recess 139 in housing 58. Once screws 143a,b are fastened into housing 58 and bolt 133 is rotated to push pivot 134 to its highest, the door is operable.
If repairs to door closer 73 are required, spindle 105a is turned in the opposite direction to retract, and raise, assembly 100. Sled 150 is reinserted under extrusion 33a and it and door 28a, and all of the combined weight, are moved back away from the cover 78 of foundation 77, to allow access thereto by flipping up front section 151a. Because of the amount of space surrounding header 35, pivot block 136 is able to tilt (as shown in phantom in FIG. 12), thus allowing the top of extrusion 33a to remain in its rotatable position and extrustion 33a and panel 28a to remain in a substantially vertical position. This procedure is reversed to re-install the door. These and other variations in the details of the system may be made in accordance with the invention, which is to be broadly construed and to be defined by the scope of the claims appended hereto. | A doorway system, comprising a novel mechanism for controlling tall glass doors and making their installation and repair much easier, and a header that can be used with standard size or tall glass doors, is disclosed. The mechanism features circular bearings, a specially-designed bottom spindle and an upper, adjustable, pivotable housing. The header houses, among other parts, the adjustable housing and allows pre-cut, modular parts to be assembled at the building site. | 4 |
BACKGROUND OF THE INVENTION
Because of environmental considerations, the substantial increase in the cost of hydrocarbons, the problem of contamination of the dispensed product by the propellant, and the problem of flammability, there has been considerable research and development activity in recent years to find other expulsion means for aerosol-type and other pressurized dispensers.
For many years there have been manual pump-type dispensers, some of which are still in use, and there have been various attempts to use spring-loaded diaphragms and other mechanical means to provide expulsion pressure, but for several reasons each type has had serious deficiencies. Gaseous media other than the usual freon and freon derivatives and homologs, and isobutane/butane mixtures, have also had their drawbacks, e.g., the required useful pressures have either been too high, depending on the compressibility of the gas, and/or constant dispensing pressure over the useful life of the packaged contents was not possible.
Furthermore, as previously mentioned, it is frequently desirable in some applications that the pressure generating medium not mix in direct contact with the product to be dispensed.
One recent development that has apparently solved the above problems and achieved substantial success is the invention disclosed and claimed in U.S. patent application Ser. No. 105,216 filed Dec. 19, 1979 abandoned in favor of continuation application Ser. No. 223,422, filed on Jan. 8, 1981, owned by the common assignee hereof. The latter invention utilizes a flexible enclosed plastic bag containing an envelope attached to the interior walls of the bag and having pockets carrying one of a two-component gas generating mixture therein which are sequentially opened during expansion of the bag to empty the contents into the bag in admixture with the second gas generating components to generate additional gas. The preferred components are citric acid and sodium bicarbonate which in admixture generate carbon dioxide gas.
In said prior application the bag is fabricated at the point of assembling the aerosol can, and water, sodium bicarbonate and a starting capsule or tablet containing an aliquot of the citric acid are inserted, the bag being heat sealed and inserted into the can just prior to filling the can with the product and sealing of the can.
The present invention is a further extension of the latter concept providing greater utility and flexibility in the manufacture of aerosol-type dispensers and permitting the geographical separation of the various manufacturing operations.
BRIEF SUMMARY OF THE INVENTION
The present inventive concept involves a flexible inflatable bag for use as an expulsion means in an aerosol-type fluid product dispenser which can be completely fabricated, ready for use, but transportable to other geographical locations for incorporation into the other dispensing apparatus. The gas generating components, including the solvent medium (e.g. water) and time release starting capsule, are separated in the bag as initially constructed, but readily mixable by appropriate mechanical manipulation of the package at the point of final assembly with said other dispensing apparatus.
Basically, the bag comprises a first group of compartments disposed in the bag in serial alignment containing a first gas generating component such as citric acid, powdered or in a water solution. The compartments are releasably sealed to the internal sidewall of said bag in the collapsed condition. The second component (e.g. sodium bicarbonate) is disposed within the bag external of the first group of compartments. A solvent medium such as water is contained in a separate rupturable separate bag or compartment inside the bag. A time release capsule of the first component is located in the bag, usually adjacent the second component, such that it can be dissolved in the solvent medium when desired to initially activate the gas generating system, i.e., at the point of final assembly of the bag into an aerosol can, and thus brought into admixture with the second component. The first group of compartments is successively unsealable from the sidewall of the bag during expansion of the bag to discharge the first component therein into admixture with the solvent containing the second component, to maintain generation of said gas and a relatively constant pressure thereof until the bag reaches its fully expanded condition.
Such a unitary bag construction permits automatic fabrication and assembly of the bags in a continuous strip of successive bags which can be rolled up and shipped to a final assembly location and sequentially severed, activated and assembled with the other aerosol product and can components by automatic machines.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational section of a typical aerosol-type container incorporating the bag of the present invention;
FIG. 2 is a sectionalized top plan view of a similar container showing the bag in initial collapsed condition;
FIG. 3 is sectionalized top plan view of the device of FIG. 2 during initial activation of the bag;
FIG. 4 is an enlarged top plan view of one embodiment of the bag;
FIG. 5 is a longitudinal section taken along lines 5--5 of FIG. 4;
FIG. 6 is a transverse section taken along lines 6--6 of FIG. 4;
FIG. 7 is an enlarged fragmentary section of the bag showing one of the gas generating component compartments;
FIG. 8 is a schematic flowsheet depicting the assembly steps for fabricating the embodiment of the bag shown on the foregoing figures;
FIG. 9 is a schematic flowsheet depicting the final assembly steps of the bag with the fluid product and the other aerosol can components;
FIG. 10 is an enlarged top plan view of another embodiment of the bag;
FIG. 11 is a longitudinal section taken along lines 11--11 of FIG. 10;
FIG. 12 is a transverse section taken along lines 12--12 of FIG. 10; and
FIG. 13 is a schematic flowsheet depicting the assembly steps for fabricating the embodiment of the bag shown in FIGS. 10-12.
DETAILED DESCRIPTION
Referring now to the drawings, one embodiment of the bag assembly according to the present invention is shown in FIGS. 4-6 and designated generally by reference numeral 10.
The bag is comprised of plastic sheets 11 and 12 which in the embodiment shown are generally rectangular in shape and adhered to one another, e.g., by heat sealing or other conventional methods, at their respective margins 13 to provide the sidewalls of the bag-like device with an open interior 14.
Sheet 11 has a plurality of compartments or recesses 15 formed therein by vacuum forming or other conventional means, each such recess facing the inner surface 16 of opposite sheet 12 (see FIG. 5).
Recesses 15 are disposed generally longitudinally of said bag assembly 10 in a staggered fashion at one side thereof and disposed within each such recess in one component 17 of a two-component gas generating system, e.g., citric acid, which can be either in powdered or water solution form, or sodium bicarbonate in powdered or water solution form as desired. Recesses 15 are closed by separate plastic sheet 18 which is releasably adhered to sheet 11 along the marginal areas 19 surrounding said plurality of recesses 15 by suitable means such as heat sealing. Sheet 18 on its outer surface, i.e., the surface opposite that in contact with sheet 11, is permanently adhered to inner surface 16 of outer bag sheet 12 along longitudinal portion or separation seal 20 and sheet 18 is further adhered to sheet 11 by angular portions or guard seals 20a adjacent respective recesses 15 (see FIG. 4), all such connections designed to provide a sequential opening of recesses 15 during use which will be described in detail hereinafter.
A separate, smaller, independent bag 21 is disposed within larger bag 10 adjacent the longitudinal side opposite that on which recesses 15 are disposed, or to the right as viewed in FIG. 4. Bag 21 is charged with the solvent medium, e.g., water, and is fabricated of suitable, rupturable sheet material for purposes to be described.
At the interior bottom portion 22 of bag 10 is disposed second gas generating component 23, e.g., sodium bicarbonate or citric acid. This component is in dry powdered form. Two time release capsules 24 containing the same gas generating component as the recesses 15 are also disposed at the bottom portion 22 of bag 10 adjacent component 23.
Bag 10 may be constructed of a flexible, fluid impermeable plastic such as, for example, polyethylene or polypropylene and in one embodiment may be a laminated plastic of low-density polyethylene and polypropylene with optionally one or more intermediate plastic layers of other materials (see FIG. 7). The low-density polyethylene layer may vary from about 0.5 to about 20 mils in thickness and the polypropylene layer from about 0.1 to about 3.75 mils thickness or more. Bag 10 may also be fabricated if desired from foil (e.g., aluminum foil) or from a foil/plastic laminate. The latter composite bag structure is particularly suitable when the present invention is used for dispensing medicines or drugs and the like. Where releasable seals have been mentioned hereinabove, using the laminated polyethylene/polypropylene would involve polypropylene to polyethylene contacting surfaces of the respective sheets involved, i.e., non-homogeneous or incompatible interfaces, and where a permanent seal is required, a polypropylene to polypropylene, or polyethylene to polyethylene, interface is required, i.e., homogeneous or compatible interfaces, all of which is well known to those skilled in the art. Other permanent and releasable sealing methods can be employed by the use of appropriate separate conventional and well-known adhesive compositions, if desired.
While citric acid and sodium bicarbonate have been shown as suitable two-component gas generating (CO 2 ) components, it is possible that under particular circumstances other components may be used such as diluted hydrochloric acid (e.g., 10-30% up to about 35%) in place of the citric acid and lithium carbonate or calcium carbonate in place of the sodium bicarbonate. Normal operating pressure is, for example, 100 psi, the aerosol can being rated at 180 psi. The operating pressure can be predetermined by the starting charges and concentrations of the two gas generating components and the charges of the one component in recesses 15. Furthermore, the concentrations of citric acid in the recesses 15 can be varied from recess to recess, e.g., it may be desired to have heavier acid concentrations in the last one or two recesses (at the upper recesses as viewed in FIG. 4). Time release capsules 24 preferably utilize an outer shell material designed to dissolve and expose the internal citric acid within a 3 to 5 minute period with or without external heat being applied to the system to enable starting the initial activation of gas generating components and their assembly of bag 10 into aerosol can 25 before expansion of bag 10 begins.
Variations are possible. For example, water pouch or bag 21 may contain the sodium bicarbonate dissolved in the water rather than have the sodium bicarbonate in powder form in the bottom 22 of bag 10 as described above. On the other hand, the water bag 21 may contain the startup amount of citric acid dissolved in the water rather than having the startup capsules 24 in the bottom 22 of bag 10, in which case time release beaded sodium bicarbonate would be used in the bottom 22 of bag 10.
Automated assembly of bag 10 is schematically shown in FIG. 8 wherein plastic sheet 11 is delivered to Station A where the compartments 15 are formed therein by vacuum forming or the like. The so-formed sheet is then delivered to Station B where the water pouch 21 is placed on sheet 11 to one side of recesses 15 as shown. At Station C, the citric acid 17 is deposited in compartments 15. At Station D, plastic sheet 18 is releasably adhered to sheet 11 at margins 19 and angular portions 20a to enclose compartments 15 and provide assurance that the recesses will be opened one at a time. At Station E, time release capsules are deposited on sheet 11 near one end 22. At Station F, the sodium bicarbonate powder 23 is deposited on sheet 11. At Station G, top sheet 12 is sealed at its margin to sheet 11 and at portion 20 to sheet 18 providing completed bag assembly 10 ready for utilization.
As shown in FIG. 9, the fabrication of bag 10 can be effected in a continuous strip 28 providing a plurality of successive similar bags and incorporated in a supply roll 29 which may be delivered to automatic package assembly equipment shown schematically in FIG. 9. The package containing continuous strip 29 is delivered to a first Station A at which the delivery end 30 of strip 29 is held at one side by rolls 31 and the first bag member 32 is severed by cutting means 33 whereby bag 32 is delivered to receiving hopper 34 disposed over can body 35. Simultaneously during such operation rolls 31 rupture the water bag 21 as the bag 32 passes therethrough, thereby delivering water to the bottom of bag 10 to dissolve component 23 and begin activation of time release capsules 24.
Hopper 34 opens to deliver bag 32 to the interior of can 35 which is then delivered to Station B where fluid product 36 is introduced into can 35 by nozzle means 37. At Station C conventional cap means 38 including aerosol valve assembly 39 are affixed to top 49 of can 35. Prior to such sealing perforated tube 41 is inserted in the interior of can 35 to prevent expansion of bag 32 during use all the way to the sides of the can thereby possibly trapping some of the liquid product 36 and preventing dispensing thereof. Means 38 includes perforated member 42 to similarly prevent bag 32 from blocking the aerosol valve 39. After complete assembly, the fully assembled container 43 is immersed in hot water bath 44, if necessary, to activate the time release capsule and water solution of sodium bicarbonate which initially expands the bag as shown at Station D.
FIGS. 1, 2 and 3 show the overall action of the bag 10 in aerosol can 43 during use. FIG. 1 is the approximate relation of the assembly at initial activation. FIG. 2 shows the bag in its fully collapsed condition prior to activation and FIG. 3 shows the conditions of the bag during the heat activation steps.
Another embodiment of bag 10 is shown in FIGS. 10-12 and its method of assembly shown in FIG. 13. In this embodiment, in lieu of water bag 21, an enlarged recess or compartment 50 is formed in sheet 11 to one side thereof (see FIG. 6) during formation of the other recesses 15 and the solvent or water 51 is disposed therein. Rupturable plastic cover sheet 52 is heat sealed or otherwise adhered sheet 11 to enclose compartment 50.
Referring to FIG. 13, the method of assembly of the embodiment of bag 10 is shown. Sheet 11 is delivered to Station A at which recesses 15 and compartment 50 are vacuum formed. At Station B water 51 is added to compartment 50. At Station C citric acid 17 is added to recesses 15. At Station D cover sheet 18 is adhered to sheet 11 at the margins 19 and angular portions 20a to cover recesses 15 and to provide assurance that the recesses 15 will be opened one at a time. At Station E cover sheet 52 is adhered to sheet 11 to cover water compartment 50 and capsules 24 are deposited on sheet 11 near one end 22 thereof. At Station F sodium bicarbonate 23 is deposited on sheet 11. At Station G sheet 12 is adhered at its margins to sheet 11, and at portion 20 to sheet 18 to provide fully assembled bag 10.
As can be appreciated from the foregoing description, an expansible, self-contained, pressure generating unit is provided that can be fabricated at one location and conditioned for operation at another location. The unit is easily assembled in a dispensing container and provides a relatively constant dispensing pressure during use without coming into contact with the dispensed material. The container can be oriented in any position without loss of the propellant. No flammability or environmental contamination problems are involved.
When required for specific additional protection of the cavities 15 an additional outer layer of foil or film can be laminated or heat sealed to the outer surface of sheet 11 to protect the cavities.
While certain embodiments have been shown and described herein, it is to be understood that certain changes can be made by those skilled in the art without departing from the scope and spirit of the invention. | A fluid impervious expandable enclosed bag containing separately compartmented first and second gas generating components which, upon admixture in successive amounts, generate gas causing the bag to expand gradually from a collapsed condition to an ultimately fully expanded condition. The internal compartmentation in the bag also contains a solvent medium and a time release capsule of one of the components, thereby providing apparatus that can be mass produced and used for insertion into aerosol-type liquid product dispensing containers to provide relatively constant expulsion pressure during use. | 1 |
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to a smoothing method for suppressing fluctuating artifacts during noise reduction.
In digital voice signal transmission, noise suppression is an important aspect. The audio signals captured by means of a microphone and then digitized contain not only the user signal ( FIG. 1 ) but also ambient noise which is superimposed on the user signal ( FIG. 2 ). In hands free installations in vehicles, for example, not only the voice signals but also engine and wind noise is captured, and in the case of hearing aids it is constantly changing ambient noise such as traffic noise or people speaking in the background, such as in a restaurant. This allows the voice signal to be understood only with increased effort. Accordingly, the noise reduction aims to make it easier to understand the voice. Therefore, a reduction in the noise must also not audibly distort the voice signal.
For noise reduction, the spectral representation is an advantageous representation of the signal. In this case, the signal is represented broken down into frequencies. One practical implementation of the spectral representation is short-term spectra, which are produced by dividing the signal into short frames ( FIG. 3 ) which are subjected to spectral transformation separately from one another ( FIG. 4 ). In this case, at a sampling rate of f s =8000 Hz, a signal frame may comprise M=256 successive digital signal samples, for example, which then corresponds to a duration of 32 ms. A transformed frame then comprises M “frequency bins”. The squared amplitude value of a frequency bin corresponds to the energy which the signal contains in the narrow frequency band of approximately 31 Hz bandwidth which is represented by the respective frequency bin. On account of the properties of symmetry of the spectral transformation, only M/2+1 of the M frequency bins, that is to say in the above example 129 bins, are relevant to the signal representation. With 129 relevant bins and 31 Hz bandwidth per bin, a spectral band from 0 Hz to approximately 4000 Hz is covered in total. This is sufficient to describe many voice sounds with sufficient spectral resolution. Another common bandwidth is 8000 Hz, which can be achieved using a higher sampling rate and hence more frequency bins for the same frame duration. In a short-term spectrum, the frequency bins are indexed by means of μ. The index for frames is λ. The amplitudes of the short-term spectrum for a frame λ are denoted generally as spectral magnitude G μ (λ) in this case. A complete short-term spectrum comprising the M frequency bins of a frame is obtained from the amplitudes G μ (λ) of the indices μ=0 to μ=M−1, that is to say μ=0 . . . M−1. For real time signals, short-term spectra satisfy the symmetry condition G μ (λ)=G M − μ (λ). A common form of presentation of the short-term spectra is what are known as spectrograms, which are formed by stringing together chronologically successive short-term spectra (cf. FIGS. 6 to 9 , by way of example).
An advantage of the spectral representation is that the fundamental voice energy is present in a concentration in a relatively small number of frequency bins ( FIGS. 4 and 6 ), whereas in the time signal all digital samples are of equal relevance ( FIG. 3 ). The signal energy in the interference is in most cases distributed over a relatively large number of frequency bins. Since the frequency bins contain a different amount of voice energy, it is possible to suppress the noise in those bins which contain only little voice energy. The more narrowband the frequency bins, the more successful this separation.
For the noise reduction, a spectral weighting function is estimated which can be calculated on the basis of different optimization criteria. It provides low values or zero in frequency bins in which there is primarily interference, and values close or equal to one for bins in which voice energy is dominant ( FIG. 5 ). The weighing function is generally reestimated for each signal frame in each frequency bin. The total amount of the weighting values for all frequency bins of a frame is also referred to as the “short-term spectrum of the weighting function” or simply as the “weighting function” in this case.
Multiplying the weighting function by the short-term spectrum of the noisy signal produces the filtered spectrum, in which the amplitudes of the frequency bins in which interference is dominant are greatly reduced, while voice components remain almost without influence ( FIGS. 8 and 9 ).
Estimation errors when calculating the spectral weighting function, what are known as fluctuations, occasionally result in excessive weighting values for frequency bins which contain primarily interference ( FIG. 8 ). This happens regardless of spectrally adjacent or chronologically preceding values. Fluctuations also even arise in spectral intermediate magnitudes, such as the estimate of the signal-to-noise ratio (SNR). Following multiplication of the weighting function containing estimation errors by the noisy short-term spectrum, the filtered spectrum contains single frequency bins which contain primarily interference and nevertheless have relatively high amplitudes. These bins are called outliers. When a time signal is synthesized from the filtered short-term spectra, the occasional outliers can be heard as tonal artifacts (musical noise), which are perceived as particularly irritating on account of their tonality ( FIGS. 10 and 11 ). A single tonal artifact has the duration of a signal frame, and its frequency is determined by the frequency bin in which the outlier occurred.
To suppress fluctuations in the weighting function or in spectral intermediate magnitudes or suppress outliers in the filtered spectrum, these spectral magnitudes can be smoothed by an averaging method and hence rid of excess values. Spectral variables for a plurality of spectrally adjacent or chronologically successive frequency bins are in this case accounted for to form an average, so that the amplitude of individual outliers is put into relative terms. Smoothing is known over frequency [1: Tim Fingscheidt, Christophe Beaugeant and Suhadi Suhadi. Overcoming the statistical independence assumption w.r.t. frequency in speech enhancement. Proceedings, IEEE Int. Conf. Acoustics, Speech, Signal Processing (ICASSP), 1:1081-1084, 2005], in the course of time [2: Harald Gustafsson, Sven Erik Nordholm and Ingvar Claesson. Spectral subtraction using reduced delay convolution and adaptive averaging. IEEE Transactions on Speech and Audio Processing, 9(8): 799-807, November 2001] or as a combination of temporal and spectral averaging [3: Zenton Goh, Kah-Chye Tan and B. T. G. Tan. Postprocessing method for suppressing musical noise generated by spectral subtraction. IEEE Transactions on Speech and Audio Processing, 6(3):287-292, May 1998]. A drawback of smoothing over frequency is that accounting for a plurality of frequency bins involves the spectral resolution being reduced, that is to say that it becomes more difficult to distinguish between voice bins and noise bins. Temporal smoothing by combining successive values of a bin reduces the temporal dynamics of spectral values, that is to say their capability of following rapid changes in the voice over time. Distortion of the voice signal is the result (clipping). In addition, an irritating residual noise correlated to the voice signal can become audible (noise shaping). These smoothing methods in the spectral domain therefore need to be adapted to suit the voice signal, generally in complex fashion.
A further known form of smoothing individual short-term spectra over frequency is a method known as “liftering” [4: Andrzej Cryzewski. Multitask noisy speech enchangement system. http://sound.eti.pg.gda.pl/denoise/main.html, 2004], [5: Francois Thibault. High-level control of singing voice timbre transformations. http://www.music.mcgill.ca/thibault/Thesis/-node43.html, 2004]. In this case, the short-term spectrum of a frame λ is first of all transformed into what is known as the cepstral domain. The cepstral representation of the spectral amplitudes G u (λ) is calculated as
G cepst μ ′ ( λ ) = IDFT { log ( G μ ( λ ) ) } ,
μ ′ = 0 … ( M - 1 ) , μ = 0 … ( M - 1 ) ( 1 )
where IDFT {•} corresponds to the inverse discrete Fourier Transformation (DFT) of a series of values of length M. This transformation results in M transformation coefficients
G cepst μ ′ ( λ ) ,
what are known as the cepstral bins with index μ′. According to equation (1), the cepstrum basically comprises a nonlinear map, namely the logarithmization, of a spectral magnitude available as an absolute value and of a subsequent transformation of this logarithmized absolute value spectrum with a transformation. The advantage of cepstral representation of the amplitudes ( FIG. 14 ) is that voice is no longer distributed over the frequency in the manner of a comb ( FIGS. 4 and 6 ), but rather the fundamental information about the voice signal is represented in the cepstral bins with the small index. Furthermore, fundamental voice information is still represented in the relatively easily detected cepstral bin with a higher index, which represents what is known as the pitch frequency (voice fundamental frequency) of the speaker.
A smoothed short-term spectrum can be calculated by setting cepstral bins with relatively small absolute values to zero and then transforming back the altered cepstrum to a short-term spectrum again. However, since severe fluctuations or outliers result in correspondingly high amplitudes in the cepstrum, these artifacts cannot be detected and suppressed by these methods.
As an alternative to liftering, there is also the method according to [6: Petre Stoica and Niclas Sandgren. Smoothed nonparametric spectral estimation via cepstrum thresholding. IEEE Signal Processing Magazine, pages 34-45, November 2006]. In this case, cepstral bins selected on the basis of a criterion are not set to zero, but rather are set to a value which is optimum for estimating long-term spectra for steady signals from short-term spectra. This form of estimation of signal spectra does not generally provide any advantages for highly transient signals such as voice.
BRIEF SUMMARY OF THE INVENTION
Against this background, the invention is based on the object of demonstrating, for the noise reduction, a smoothing method for suppressing fluctuations in the weighting function or in spectral intermediate magnitudes or outliers in filtered short-term spectra which neither reduces the frequency resolution of the short-term spectra nor adversely affects the temporal dynamics of the voice signal.
This object is achieved by means of a smoothing method having the measures of patent claim 1 . Advantageous developments are the subject matter of the subclaims.
The smoothing method according to the invention comprises the following steps:
short-term spectra for a series of signal frames are provided, each short-term spectrum is transformed by forward transformation, which describes the short-term spectrum using transformation coefficients which represent the short-term spectrum divided into its coarse and its fine structures, the transformation coefficients with the same coefficient indices in each case are smoothed by combining at least two successive transformed short-term spectra, and the smoothed transformation coefficients are transformed into smoothed short-term spectra by backward transformation.
The smoothing method according to the invention uses a transformation such as the cepstrum in order to describe a broadband voice signal with as few transformation coefficients as possible in its fundamental structure. Unlike in known methods, the transformation coefficients are not set to zero independently of one another if they are below a threshold value, however. Instead, the values of transformation coefficients from at least two successive frames are accounted for together by smoothing over time. In this case, the degree of smoothing is made dependent on the extent to which the spectral structure represented by the coefficient is crucial to describing the user signal. By way of example, the degree of temporal smoothing of a coefficient is therefore dependent on whether a transformation coefficient contains a large amount of voice energy or little. This is easier to determine in the cepstrum or similar transformations than in the short-term spectrum. By way of example, it may thus be assumed that the first four cepstral coefficients with indices μ′=0 . . . 3 and additionally the coefficient with a maximum absolute value and index μ′ greater than 16 and less than 160 at f s =8000 Hz (pitch) represent voice. Coefficients with a large amount of voice information are smoothed only to the extent that their temporal dynamics do not become less than in the case of a noiseless voice signal. If appropriate, these coefficients are not smoothed at all. Voice distortions are prevented in this way. Since spectral fluctuations and outliers represent a short-term change in the fine structure of a short-term spectrum, they are mapped in the transformed short-term spectrum as a short-term change in those transformation coefficients which represent the fine structure of the short-term spectrum. Since these transformation coefficients have a relatively low rate of change over time in the case of noiseless voice, these very coefficients can be smoothed much more. Heavier temporal smoothing therefore counteracts the formation of outliers without influencing the structure of the voice. The smoothing method therefore does not result in decreased spectral resolution for voice sounds. The change in the fine structure of the short-term spectrum in the case of successive frames is delayed such that only narrowband spectral changes with time constants below those of noiseless voice are prevented.
From the smoothed magnitude, denoted as
G cepst μ ′ smooth ( λ ) ,
it is possible to obtain a spectral representation of the smoothed short-term spectrum again by backward transformation. For a cepstral representation, as described in (1), one possible backward transformation is as follows:
G μ , smooth ( λ ) = exp ( DFT { G cepst μ ′ smooth ( λ ) } ) ,
μ = 0 … ( M - 1 ) , μ ′ = 0 … ( M - 1 ) , ( 2 )
where DFT{ } corresponds to the discrete Fourier transformation and exp( ) corresponds to the exponential function which is applied element by element in (2).
The advantages which result from the inventive smoothing of short-term spectra are as follows:
effective suppression of fluctuations or outliers, retention of the spectral resolution for voice signals, and no audible influencing of voice.
It is important to note that the inverse DFT used for the cepstrum in (1) and the DFT for the backward transformation in (2) can be replaced by other transformations without thereby losing the basic properties of the transformation coefficients with regard to the compact representation of voice. The same situation applies to the logarithmization in (1) and the corresponding reversal function in (2), the exponential function. In these cases too, other nonlinear maps and also linear maps are conceivable.
Transformations differ in the base functions used thereof. The process of transformation means that the signal is correlated to the various base functions. The resulting degree of correlation between the signal and a base function is then the associated transformation coefficient. A transformation involves production of as many transformation coefficients as there are base functions. The number thereof is denoted by M in this case. Transformations which are important for the invention are those whose base functions break down the short-term spectrum to be transformed into its coarse structure and its fine structure.
A distinguishing feature of transformations is the orthogonality. Orthogonal transformation bases contain only base functions which are uncorrelated. If the signal is identical to one of the base functions, orthogonal transformations result in transformation coefficients with the value zero, apart from the coefficient which is identical to the signal. The selectivity of an orthogonal transformation is accordingly high. Nonorthogonal transformations use function bases which are correlated to one another.
A further feature is that the base functions for the incidence of application under consideration are discrete and finite, since the processed signal frames are discrete signals with the length of a frame.
An important feature of a transformation is the invertability. If there is an inverse transformation for a transformation (forward transformation), transforming a signal into transformation coefficients and subsequently subjecting these coefficients to inverse transformation (backward transformation) produces the initial signal again if the transformation coefficients have not been altered.
In the signal processing as described here, Discrete Fourier Transformation (DFT) is a preferred transformation. An associated important algorithm in discrete signal processing is “Fast Fourier Transformation” (FFT). In addition, Discrete Cosine Transformation (DCT) and Discrete Sine Transformation (DST) are frequently used transformations. In this case, these transformations are combined under the term “standard transformations”. An already mentioned property of standard transformations which is crucial to the invention is that the amplitudes of the various transformation coefficients represent different degrees of fine structure for the transformed signal. Thus, coefficients with small indices describe the coarse structures of the transformed signal, because the associated base functions are audio-frequency harmonic functions. The higher the index of a transformation coefficient up to μ′=M/2, the finer the structures of the transformed signal which are described by said coefficients. For coefficients beyond this, this property is turned around on account of the symmetry of the coefficients. Usually, signal processing involves only the coefficients with indices μ′=0 to μ′=M/2 being processed and the remaining values being ascertained by mirroring the results.
In addition, the invertability of the transformations makes it possible to interchange the transformation and the inverse thereof in the forward and backward transformation. In (1), it is thus also possible to use the DFT from (2), for example, if the IDFT from (1) is used in (2).
Advantageously, the spectral coefficients of the short-term spectra are mapped nonlinearly before the forward transformation. A basic property of nonlinear mapping which is advantageous for the invention is dynamic compression of relatively large amplitudes and dynamic expansion of relatively small amplitudes.
Accordingly, the spectral coefficients of the smoothed short-term spectra can be mapped nonlinearly after the backward transformation, the nonlinear mapping after the backward transformation being the reversal of the nonlinear mapping before the forward transformation.
Expediently, the spectral coefficients are mapped nonlinearly before the forward transformation by logarithmization.
A form of temporal smoothing can be achieved by a preferably first-order recursive system:
G
cepst
μ
′
,
smooth
(
λ
)
=
β
u
′
G
cepst
μ
′
,
smooth
(
λ
-
1
)
+
(
1
-
β
μ
′
)
c
(
λ
)
.
(
3
)
Possible values for the smoothing constants for coefficients of the standard transformations in the case of voice signals are β μ′ =0 for μ′=0 . . . 3, β μ′ =0.8 for μ′=4 . . . M/2 with the exception of the transformation coefficients which represent the pitch frequency of a speaker, and β μ′ =0.4 for transformation coefficients which represent the pitch frequency. Methods for determining the pitch coefficient are widely available in the literature. By way of example, to determine the coefficient for the pitch, it is possible to select that coefficient whose index is between μ′=16 and μ′=160 and which has the maximum amplitude of all the coefficients in this index range. For the remaining transformation coefficients with indices μ′=M/2+1 . . . M−1, the symmetry condition β M−μ′ =β μ′ applies. The values are suitable for the standard transformations and also short-term spectra which have arisen from signals where f s =8000 Hz. They can be adapted to suit other systems by proportional conversion. The selection β μ′ =0 means that the relevant coefficients are not being smoothed. A crucial property of the invention is that coefficients which describe the coarse profile of the short-term spectrum are smoothed as little as possible if voice signals are being denoised. Thus, the coarse structures of the broadband voice spectrum are protected from smoothing effects. The fine structures of fluctuations or spectral outliers are mapped in the transformation coefficients between μ′=4 and μ′=M/2 in the case of standard transformations, which is why said transformation coefficients are smoothed much apart from the pitch of the voice.
Advantageously, the smoothing method is applied to the absolute value or a power of the absolute value of the short-term spectra.
It is particularly advantageous if different time constants are used to smooth the respective transformation coefficients. The time constants can be chosen such that the transformation coefficients which represent primarily voice are smoothed little. Expediently, the transformation coefficients which describe primarily fluctuating background noise and artifacts of the noise reduction algorithms can be smoothed much.
The short-term spectrum provided may be the spectral weighting function of a noise reduction algorithm. Advantageously, the short-term spectrum used may also be the spectral weighting function of a post filter for multichannel methods for noise reduction. Expediently, the spectral weighting function is in this case obtained from the minimization of an error criterion.
The short-term spectrum provided may also be a filtered short-term spectrum.
According to another development of the method, the short-term spectrum provided is a spectral weighting function of a multichannel method for noise reduction.
The short-term spectrum provided may also be an estimated coherence or an estimated “Magnitude Squared Coherence” between at least two microphone channels.
Advantageously, the short-term spectrum provided is a spectral weighting function of a multichannel method for speaker or source separation.
In addition, provision is made for the short-term spectrum provided to be a spectral weighting function of a multichannel method for speaker separation on the basis of phase differences for signals in the various channels (Phase Transform—PHAT).
In addition, it is possible for the short-term spectrum used to be a spectral weighting function of a multichannel method on the basis of a “Generalized Cross-Correlation” (GCC). The short-term spectrum provided may also be spectral magnitudes which contain both voice and noise components.
The short-term spectrum provided may also be an estimate of the signal-to-noise ratio in the individual frequency bins. In addition, the short-term spectrum used may be an estimate of the noise power.
The problem of fluctuations in short-term spectra is known not only in audio signal processing. Further advantageous areas of application are image and medical signal processing.
In image processing, the rows of an image can be interpreted as a signal frame, for example, which can be transformed into the spectral domain. In this case, the frequency bins produced are called local frequency bins. When images are processed in the local frequency domain, algorithms are used which are equivalent to those in audio signal processing. Possible fluctuations which these algorithms produce in the local frequency domain result in visual artifacts in the processed image. These are equivalent to tonal noise in audio processing.
In medical signal processing, signals are derived from the human body which may exhibit noise in the manner of audio signals. The noisy signal can be transformed into the spectral domain frame by frame as appropriate. The resultant spectrograms can be processed in the manner of audio spectra.
The smoothing method can be used in a telecommunication network and/or for a broadcast transmission in order to improve the voice and/or image quality and in order to suppress artifacts. In mobile voice communication, distortions in the voice signal arise which are caused firstly by the voice coding methods used (redundancy-reducing voice compression) and the associated quantization noise and secondly by the interference brought about by the transmission channel. Said interference in turn has a high level of temporal and spectral fluctuation and results in a clearly perceptible worsening of the voice quality. In this case, too, the signal processing used at the receiver end or in the network needs to ensure that the quasi-random artifacts are reduced. To improve quality, what are known as post filters and error masking methods have been used to date. Whereas the post filter predominantly has the task of reducing quantization noise, error masking methods are used to suppress transmission-related channel interference. In both applications, improvements can be attained if the smoothing method according to the invention is integrated into the post filter or the masking method. The smoothing method can therefore be used as a post filter, in a post filter, in combination with a post filter, as part of an error masking method or in conjunction with a method for voice and/or image coding (decompression method or decoding method), particularly at the receiver end. When the method is used as a post filter, this means that the method is used for post filtering, that is to say an algorithm which implements the method is used to process the data which arise in the applications. It is also possible to improve the quality of the voice signal in the telecommunication network by smoothing the voice signal spectrum or a magnitude derived therefrom using the smoothing method according to the invention.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
The invention is explained in more detail below with reference to illustrations which are shown in the figures, in which:
FIG. 1 shows a noiseless time signal;
FIG. 2 shows a noisy time signal;
FIG. 3 shows a single signal frame in the time domain;
FIG. 4 shows a single signal frame in the spectral domain;
FIG. 5 shows a weighting function for a single frame;
FIG. 6 shows the spectrogram of a noiseless signal;
FIG. 7 shows the spectrogram of a noisy signal;
FIG. 8 shows the spectrogram of a signal filtered using the unsmoothed weighting function
FIG. 9 shows the spectrogram of a signal filtered using a weighting function smoothed in accordance with the invention;
FIG. 10 shows a filtered time signal with tonal artifacts;
FIG. 11 shows a time signal filtered in accordance with the invention;
FIG. 12 shows the spectrogram of an unsmoothed weighting function;
FIG. 13 shows the spectrogram of a weighting function smoothed in accordance with the invention;
FIG. 14 shows the absolute value of the cepstrum of a noiseless voice signal, and
FIG. 15 shows the signal flowchart in accordance with a preferred embodiment of the invention.
DESCRIPTION OF THE INVENTION
FIG. 1 shows a noiseless signal in the form of the amplitude over time. The duration of the signal is 4 seconds, and the amplitudes range from approximately −0.18 to approximately 0.18. FIG. 2 shows the signal in noisy form. It is possible to see a random background noise over the entire time profile.
FIG. 3 shows the signal for an individual signal frame λ. The signal frame has a segment duration of 32 milliseconds. The amplitude of both graphs varies between −0.1 and 0.1. The individual samples of the digital signals are connected to form graphs. The noisy graph represents the input signal, which contains the noiseless signal. Separation of signal and noise in the noisy signal is almost impossible in this representation of the signal.
FIG. 4 shows a representation of the same signal frame following the transformation into the frequency domain. The individual frequency bins μ are connected to form graphs. In this figure too, the frequency bins are shown in noisy and noiseless form, the noiseless signal again being the voice signal which the noisy signal contains. The frequency bins μ from 0 to 128 are shown on the abscissa. They have amplitudes of approximately −40 decibels (dB) to approximately 10 dB. By comparing the graphs, it is possible to see that the energy in the voice signal is concentrated in individual frequency bins in a comb-like structure, whereas the noise is also present in the bins in between.
FIG. 5 shows a weighting function for the noisy frame from FIG. 4 . For each frequency bin μ, a factor of between 0 and 1 is obtained on the basis of the ratio of voice energy and noise energy. The individual weighting factors are connected to form a graph. It is again possible to see the comb-like structure of the voice spectrum.
FIGS. 6 and 7 show spectrograms comprising a series of noiseless and noisy short-term spectra ( FIG. 4 ). The frame index λ is plotted on the abscissa, and the frequency bin index μ is plotted on the ordinate. The amplitudes of the individual frequency bins are shown as grayscale values. In comparing FIGS. 6 and 7 , it becomes clear how voice is concentrated in few frequency bins. In addition, it forms regular structures. By contrast, the noise is distributed over all frequency bins.
FIG. 8 shows the spectrogram for a filtered signal. The axes correspond to those from FIGS. 6 and 7 . From a comparison with FIG. 6 , it is possible to see that estimation errors in the weighting function mean that high amplitudes remain in frequency bins which contain no voice. Suppressing these outliers is the aim of the method according to the invention.
FIG. 9 shows the spectrogram for a signal which, in line with one preferred development of the method according to the invention, has been filtered using a smoothed weighting function. The axes correspond to those of the preceding spectrograms. In comparison with FIG. 8 , the outliers are greatly reduced. The voice components in the spectrogram are by contrast obtained in their fundamental form.
FIGS. 10 and 11 show time signals which are respectively obtained from the filtered spectra in FIGS. 8 and 9 . The amplitude is plotted over time. The signals are 4 seconds long and have amplitudes between approximately −0.18 and 0.18. In the associated time signal in FIG. 10 , the outliers in the spectrogram from FIG. 8 produce clearly visible tonal artifacts which are not present in the noiseless signal from FIG. 1 . The time signal in FIG. 11 has a significantly quieter profile for the residual noise. This time signal is obtained from a spectrogram from FIG. 9 , which was produced by filtering using the smoothed weighting function.
FIG. 12 shows the unsmoothed weighting function for all frames. For each frame λ, frequency bins μ are plotted along the ordinate. The values of the weighting function are shown in gray. The fluctuations which result from estimation errors can be seen as irregular blotches.
FIG. 13 shows the smoothed weighting function for all frames. The axes correspond to those from FIG. 12 . The smoothing spreads the fluctuations and greatly reduces their value. By contrast, the structure of the voice frequency bins continues to be clearly visible.
FIG. 14 shows the absolute value of the cepstrum of a noiseless signal over all frames. For each frame λ, cepstral bins μ′ are plotted along the ordinate. The values of the absolute values of the cepstral coefficients
G cepst μ ′ ( λ )
are shown in gray. A comparison with FIG. 6 shows that voice in the cepstrum is concentrated over an even smaller number of coefficients. Furthermore, the position of these coefficients is less variable. It is also possible to clearly see the profile of the cepstral coefficient which represents the pitch frequency.
FIG. 15 shows a signal flowchart in accordance with a preferred embodiment of the invention. A noisy input signal is transformed into a series of short-term spectra, these are then used to estimate a weighting function for filtering over spectral intermediate magnitudes. One frame at a time is handled in each case. First of all, the short-term spectra for the weighting function are subjected to nonlinear, logarithmic mapping. This is followed by forward transformation into the cepstral domain. The short-term spectra transformed in this manner are therefore represented by transformation coefficients for the base functions. The transformation coefficients calculated in this way are smoothed separately from one another using different time constants. The recursive nature of the smoothing is indicated by tracing the output of the smoothing to its input. Of the signal paths for a total of M transformation coefficients, only three are shown, the remainder having being replaced by three dots “ . . . ”. The smoothing is followed by backward transformation and then the nonlinear reversal mapping. In this way, the result obtained is a series of smoothed short-term spectra for the weighting function. These smoothed short-term spectra for the weighting function can be multiplied by the noisy short-term spectra, which produces filtered short-term spectra with a few outliers. These are then converted into a time signal with the reduced noise level. The portion of the signal flowchart which describes the smoothing according to the invention is surrounded by dashed border. | A smoothing method for suppressing fluctuating artifacts in the reduction of interference noise includes the following steps: providing short-term spectra for a sequence of signal frames, transforming each short-term spectrum by way of a forward transformation which describes the short-term spectrum using transformation coefficients that represent the short-term spectrum subdivided into its coarse and fine structures; smoothing the transformation coefficients with the respective same coefficient indices by combining at least two successive transformed short-term spectra; and transforming the smoothed transformation coefficients into smoothed short-term spectra by way of a backward transformation. | 6 |
FIELD OF THE INVENTION
The present invention relates to a printer.
BACKGROUND OF THE INVENTION
In a printer heretofore used, when used with a continuous paper sheet, the paper sheet proceeds from a casing at a rear side into the casing main body and is printed when fed to a platen. The printed continuous paper sheet is guided by a pinch roller upwardly and is moved onto a paper shelf provided on the printer casing to be free for use or removed.
Also, in the case of the use of cut paper, the paper shelf is obliquely set at the rear portion of the printer, and at the time of paper supply, it is used as a paper guide at the time of exiting of the paper.
In such a printer as described above, in the case of the use of a separate sheet of paper, in order to set the paper shelf obliquely to the printer, a special member therefor is provided, or the printer position is changed to a position different to that when using a continuous sheet of paper, or the paper is set to be reversed in the forward and rear positions. Such procedure is complicated.
Accordingly, an object of the present invention resides in making the supply and exiting of the separate sheet of paper possible with a simple procedure without requiring special parts.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of a printer according to one embodiment of the invention in which the paper shelf is shown in its lowered position;
FIG. 2 is a partial side view, partly in section, of the printer shown in FIG. 1 but on a larger scale;
FIG. 3 is another sectional view of the printer with the paper shelf shown in its lowered position;
FIG. 4 is a sectional view of the printer showing the raised position of the paper shelf;
FIG. 5 is an enlarged partial side view of the printer; and
FIGS. 6(A) to 6(E) are enlarged side views showing different operating positions.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following, an explanation will be given of an embodiment of the present invention by referring to the drawings. As shown in FIG. 1, at the upper portion of the forward side (the left side in FIG. 1) of a printer casing 1, there is attached a cover 2 which is freely pivotable about a pivot 3. The terminal end portion of the cover 2 bends slightly to the lower side, and at the forward terminal end thereof, a cutter portion 2a of a knife-like shape is formed with a predetermined width. At both sides of the cutter portion, there are formed side plates 2b, and these side plates are elongated slightly rearwardly from the cutter portion 2a, and as shown in FIGS. 3 and 4, at the inside of the rear portion thereof, engaging portions 2c are formed to be opposing to each other.
As shown in FIG. 1, on the casing 1 at the rear side of the cover 2, there is mounted a paper shelf 4 free to advance and retract in a range limited in the rear and forward directions.
At the forward terminal portion of the paper shelf 4, there is formed a guide portion 4a for the exiting paper arranged in such a manner that the portion 4a corresponds to the width of the above-described cutter portion 2a and is inclined toward the external circumferencial surface of the platen 5. On both sides of the paper shelf 4 are formed side plates 4b.
On the internal surface of the side plate 1b of the casing 1, there is formed a protrusion 1a for restricting the advance and retraction of the paper shelf 4, and a guide member 1h is provided for the paper shelf 4 when the paper shelf is in a position inclined to the printer as will be further described.
At the forward portion of the external surface of the side plate 4b of the paper shelf 4 there is formed a long groove 40, and the protrusion 1a is received in the long groove 40.
As shown in FIG. 3, inside the forward terminal portion of the side plate 4b, there is formed a retaining portion 4c which contacts the engaging portion 2c to prevent opening of the cover 2.
In the inside of the casing 1, as shown in FIG. 1, there is provided a printing mechanism C. The printing mechanism includes a printing head 6 mounted on a carriage 7 in a position to oppose the platen 5, and is free to be displaced while being guided by a guide shaft 8. Continuous paper P is inserted from a paper supply opening 1e at the rear portion of the casing 1 and exits on the paper shelf 4 by passing through the space between the cutter portion 2a and the guide portion 4a upon being fed to the platen 5 by the sprocket 9. Numeral 10 denotes a pinch roller contacting the platen 5.
On the upper portion of the internal side surface 1g of the printer casing 1, there is formed a groove 1f in which the side plate 4b of the paper shelf 4 is receivable.
As shown in FIG. 2, the projection 1a has a non-circular shape with a large diameter portion 11b and a short diameter portion 11a.
The long groove 40 comprises an open portion (forward portion) 41 and a rear portion 42, and the rear portion 42 comprises a rear terminal end 42a for receiving and stopping the projection 1a in the casing when the paper shelf is received in the groove 1f of the paper shelf 4. The long groove 40 also comprises first and second stopping portions 42b and 42c which correspond to the larger diameter portion 11b of the projection 1a. The forward portion 41 communicates with the first stopping portion 42b, and has a width corresponding to the shorter diameter portions 11a of the projection 1a. The depth of the long groove 40 is such that the rear terminal end thereof 42a contacts projection 1a when the forward terminal end portion 4a of the paper shelf 4 is received in the groove 1f.
An explanation will be given of the method of arranging the casing 1 and the paper shelf 4. As shown in FIG. 5, the paper shelf 4 is lowered in the direction of the arrow B from the upper portion of the printer by directing the open portion 41 downwardly, and the open portion 41 is fitted onto the short diameter portion 11a. After the open portion has passed through the short diameter portion 11a, when the paper shelf 4 is pivoted in a clockwise direction (in the direction of arrow A), as shown in FIG. 4, the down surface of the paper shelf 4 contacts the internal side surface 1g of the casing 1. At this time, as shown in FIG. 5, the long diameter portions 11b of the projection 1a opposes the first stopping portions 42b of the long groove 40. At this time, even if the paper shelf is pulled to the right side, the open portion 41 of the paper shelf 4 can not pass through the long diameter portions 11b of the projection 1a, and the paper shelf 4 is prevented form being removed from the casing main body 1, and due to the above-described procedure, the arrangement of the paper shelf 4 into the casing 1 is completed. In the case when the cover 2 is to be opened in order to exchange the ink ribbon, printing paper, etc., as shown in FIG. 4, the cover 2 is opened by being pivoted in a counterclockwise direction about the pivot 3.
An explanation will now be given of the case where a continuous paper is cut by the cover 2 when using a continuous paper in the printer.
As shown in FIGS. 2 and 3, when the paper shelf 4 is pushed to the left direction, the protrusion 1a passes the first stopping portion 42b, and the second stopping portion 42c then opposes the long diameter portion 11b of the protrusion 1a. At this time, at the inside and outside of the forward terminal end of the side plate 4b of the paper shelf 4, the upper surface of the attaching portion 2c of the cover 2 and the guide member 1h of the casing 1 contact the retaining portion 4c of the paper shelf 4 and the external side of the forward terminal portion 4c' of the side plate 4b, and the paper shelf is unable to be displaced further to the left.
As shown in FIG. 3, by such advancement of the paper shelf 4, the width of the paper outlet port between the cutter portion 2a and the guide portion 4a of the paper shelf is extremely small, and the leakage of noise to the outside of the printer during printing will be reduced, and the noise of the printer will be minimized.
Continuous paper P is inserted through the paper supply port 1e and is printed at the forward part of the platen 5. The printed paper then passes from the paper outlet port between the cutter portion 2a and the guide portion 4a on the paper shelf 4. In the case of cutting the paper P, the cutting occurs at the blade edge of the cutter portion 2a, as the paper is pulled forward. At this time, the engaging portion 2c of the cover 2 is pressed at the upper portion by the retaining portion 4c of the paper shelf 4, and since the force for pulling the paper P provides a turning moment of force in a direction for pushing the lower surface of the paper shelf 4 to the inside surface 1g of the casing 1 around the projection 1a, both the paper shelf 4 and the cover 2 are fixed and unable to move upwardly from the casing 1. Therefore, the paper P can be easily cut off at the cutting position by the cutter portion 2a.
An explanation will now be set forth of the case of using a separate sheet of paper.
As shown in FIG. 6(A), initially the cover 2 is held in a closed position by the paper shelf 4. The rear portion of the paper shelf 4 is then taken, and as shown in FIG. 6(B), when the paper shelf 4 is pivoted in the counterclockwise direction while pulling the paper shelf rearwardly, the forward terminal portion 4c' of the side plate 4b and the retaining portion 4c (not shown in FIG. 6(B)) of the paper shelf 4 are respectively guided by the guide member 1h of the casing 1 and the engaging portion 2c of the cover 2, and displaced rearwardly. As shown in FIG. 6(C), the stopping portions 42b of the paper shelf 4 reaches a position to oppose the long diameter portion 11b of the protrusion 1a, and the paper shelf 4 rotates in a counterclockwise direction with the protrusion 1a as the center, and when it has rotated for about 90 degrees, by pushing the paper shelf 4 downwardly as shown in FIG. 6(D), the forward terminal portion 4c' of the side plate 4b of the paper shelf 4 will be received in the groove 1f, and as shown in FIG. 6(E), while the paper shelf 4 is in a guiding position, and is retained in this position, the rear terminal portion 42a of the paper shelf 4 contacts the protrusion 1a, and thereby, the position of the paper shelf 4 is determined and preserved by the groove 1f and the protrusion 1a.
At this time, as shown by the broken lines in FIG. 4, the paper shelf 4 is set obliquely to the printer.
Since printing is not being carried out on the continuous paper P, the continuous paper P is disposed in a waiting position at the tractor 9.
One sheet of a separate paper P' is set on the paper shelf 4. At this time, the paper shelf 4 is set in such a manner that the circumferencial surface of the platen 5 is disposed in alignment with the guide portion 4a of the paper shelf 4.
Therefore, the separate paper P' passes about the circumference of the platen 5, and is printed in the same manner as in the case of the continuous paper, and then is discharged onto the paper shelf 4.
The shape of the protrusion is not limited to the illustrated embodiment, and may be non-circular with a sectional shape having a long diameter portion and a short diameter portion. Also the shape of the long groove 40 is not limited to the illustrated embodiment, and may have a dimension corresponding to the long diameter portion and the short diameter portion of the protrusion. Also, the long groove 40 may be provided so as not to be one body, and may be provided on the side plate 4b of the paper shelf 4 in one body, or may be provided on the paper shelf 4 in another shape. Also, various kinds of printing methods of the printer may be used other than the wire dot type such as the non-impact type, etc.
According to the present invention, the long groove in the forward part of both side portions of the paper shelf is fitted to the protrusion of both side portions of the printer casing to make it possible to rotate and to advance and retract. A casing groove is provided in the casing under the protrusion of such a depth that when the rear end of the long groove contacts the protrusion, the forward terminal portion of the paper shelf is fitted in the casing groove.
Therefore, in the case when a separate sheet of paper is used in the printer, when the paper shelf is lifted up, the paper shelf rotates around the protrusion, and the forward terminal portion of the paper shelf enters the casing groove under the protrusion, and when the rear end of the long groove contacts the protrusion, the position of the paper shelf is determined and preserved by the groove and the protrusion. Thereby, a separate paper can be supplied and discharged from the printer by means of the paper shelf.
Therefore, the supply and discharge of a separate paper sheet can be carried out with a simple procedure without requiring special parts and the production cost can be minimized.
Although the present invention has been fully described by way of example with reference to the accompanying drawings, it is to be understood that various changes and modifications will be apparent to those skilled in the art. Therefore, unless otherwise such changes and modifications depart from the scope of the invention, they should be construed as being included therein. | A printer suitable for use with either a continuous printing form or a separate printing form, includes a printer casing having projections on both sides thereof and a rearwardly inclined groove located below the projections. The paper shelf has elongated grooves formed at both sides of the front portion thereof so as to engage the projections of the printer casing, respectively. When a separate printing form is used, the rear end of the paper shelf is raised by pivoting the paper shelf about the projections of the printer casing and the front edge thereof enters the inclined groove of the printer casing so that when the rear ends of the elongated grooves engage the projections, the paper shelf is positioned by the inclined groove and the projections of the printer casing. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a novel group of compounds and more particular to a novel group of compounds particularly well suited as sweeteners in edible foodstuff.
2. Description of the Prior Art
Sweetness is one of the primary taste cravings of both animals and humans. Thus, the utilization of sweetening agents in foods in order to satisfy this sensory desire is well established.
Naturally occurring carbohydrate sweeteners such as sucrose, are still the most widely used sweetening agents. While these naturally occurring carbohydrates, i.e., sugars, generally fulfill the requirements of sweet taste, the abundant usage thereof does not occur without deleterious consequence, e.g., high caloric intake and nutritional imbalance. In fact, oftentimes the level of these sweeteners required in foodstuffs is far greater than the level of the sweetener that is desired for economic, dietic or other functional consideration.
In an attempt to eliminate the disadvantages concomitant with natural sweeteners, considerable reasearch and expense have been devoted to the production of artificial sweeteners, such as for example, saccharin, cyclamate, dihydrochalcone, aspartame, etc. While some of these artificial sweeteners satisfy the requirements of sweet taste without caloric input, and have met with considerable commercial success, they are not, however, without their own inherit disadvantages. For example, many of these artificial sweeteners have the disadvantages of high cost, as well as delay in the perception of the sweet taste, persistent lingering of the sweet taste, and a very objectionable bitter, metallic aftertaste when used in food products.
Since it is believed that many disadvantages of artificial sweeteners, particularly aftertaste, is a function of the concentration of the sweetener, it has been previously suggested that these effects could be reduced or eliminated by combining artificial sweeteners such as saccharin, with other ingredients or natural sugars, such as sorbitol, dextrose, maltose etc. These combined products, however, have not been entirely satisfactory either. Some U.S. patents which disclose sweetener mixtures include for example, U.S. Pat. No. 4,228,198; U.S. Pat. No. 4,158,068; U.S. Pat. No. 4,154,862; U.S. Pat. No. 3,717,477.
Also much work has continued in an attempt to develop and identify compounds that have a sweet taste. For example, in Yamato, et al., Chemical Structure and Sweet Taste Of Isocoumarin and Related Compounds, Chemical Pharmaceutical Bulletin, Vol. 23, p. 3101-3105 (1975) and in Yamato et al. Chemical Structure and Sweet Taste Of Isocoumarins and Related Compound, Chemical Senses And Flavor, Vol. 4 No. 1, p. 35-47 (1979) a variety of sweet structures are described. For example, 3-Hydroxy-4-methoxybenzyl phenyl ether is described as having a faint sweet taste.
Despite the past efforts in this area, research continues. Accordingly, it is desired to find a compound that provides a sweet taste when added to foodstuff or one which can reduce the level of sweetener normally employed and thus eliminate or greatly diminish a number of disadvantages associated with prior art sweeteners.
SUMMARY OF THE INVENTION
This invention pertains to sweetness compounds of the structure: ##STR2## wherein: R is methyl or ethyl;
R 1 is of the formula: ##STR3##
wherein Z is a five-membered heterocyclic ring in which the hetero atom is at least one of S, O, N and NR 2 ; wherein n is an integer from 0 to 1 when Z is a fully-saturated heterocyclic ring and, otherwise n=1,
each R 2 is selected from the group consisting of H, CH 3 , CH 2 CH 3 , CH 2 CH 2 CH 3 , CH(CH 3 ) 2 , OH, OCH 3 , CH(OH)CH 3 , OCH 2 CH 3 , OCH(CH 3 ) 2 , CH 2 OH, CH 2 CH 2 OH, CH 2 CHOHCH 3 , CH 2 OCH 3 , CHO, COCH 3 , COCH 2 CH 3 , CH 2 COCH 3 , and COOCH 3 with the proviso that R 1 contain no more than 12 carbon atoms; and salts thereof.
The heterocyclic rings representative of Z include both saturated and unsaturated rings, e.g., furyl, tetrahydrothienyl, pyrrl, thiazolyl, imidazolyl, oxazolyl, and the like. For convenience, the unsaturated heterocyclics are referred to in the specification and claims as the "aromatic heterocyclic rings".
Most of the compounds of the formula described hereinabove are sweeteners, the sweetness of which is many times that of comparable amounts of sucrose. The sweetness of compounds of the formula can be readily determined by a simple test procedure described herein.
Several compounds of the formula when tested for sweetness showed little, if any, sweetness to sucrose, whereas most compounds have greater sweetness than sucrose, e.g., 100-300 time greater. In general, the sweetener compound should possess a sweetness at least five times greater, preferably 30 times greater and more preferably 100 times greater than sucrose on comparable weight basis.
These compound in addition to having a sweet taste, function as a low calorie sweetening agent when employed with a foodstuff.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In accordance with the present invention, the preferred novel compounds are of the formula: ##STR4## wherein:
R is selected rom the group consisting of methyl and ethyl;
R 1 is of the formula ##STR5##
wherein Z is a five membered aromatic heterocyclic ring in which the hetero atom is at least one of S, O, 9 and CR 2 ; and
R 2 is selected from the group consisting of H, CH 3 , CH 2 CH 3 , CH 2 CH 2 CH 3 , CH(CH 3 ) 2 , OH, CCH 3 , OCH 2 CH 3 , CH(OH)CH 3 , OCH(CH 3 ) 2 , CH 2 OH, CH 2 CHOHCH 3 , CH 2 OCH 3 , CHO, COCH 3 , COCH 2 CH 3 , CH 2 COCH 3 , and COOCH 3 with the proviso that R 1 contain no more than 12 carbon atoms; and salts thereof.
Preferably R 1 will contain no more than 10 carbon atoms and more preferably will contain no more than 8 carbon atoms.
Illustrative compounds within the scope of the present invention include:
3-hydroxy-4-ethoxyphenyl 2-furfuryl carbonate
3-hydroxy-4-methoxyphenyl 3-tetrahydrofurfuryl carbonate
3-hydroxy-4-methoxyphenyl 2-thienylmethyl carbonate
3-hydroxy-4-methoxyphenyl 3-thienylmethyl carbonate
3-hydroxy-4-methoxyphenyl 3-furfuryl carbonate
3-hydroxy-4-methoxyphenyl 5-methyl-2-furfuryl carbonate
3-hydroxy-4-methoxyphenyl 5-methyl-2-thienylmethyl carbonate
3-hydroxy-4-methoxyphenyl 5-isopropyl-2-thienylmethyl carbonate
3-hydroxy-4-methoxyphenyl 2-tetrahydrothienylmethyl carbonate
3-hydroxy-4-methoxyphenyl N-acetyl-2-pyrrylmethyl carbonate
3-hydroxy-4-methoxyphenyl 5-acetyl-2-thienylmethyl carbonate
3-hydroxy-4-methoxyphenyl 5-methoxy-2-thienylmethyl carbonate
3-hydroxy-4-methoxyphenyl 3,5-dimethyl-2-thienylmethyl carbonate
3-hydroxy-4-methoxyphenyl 2-thiazolylmethyl carbonate
3-hydroxy-4-methoxyphenyl 5-thiazolylmethyl carbonate
3-hydroxy-4-methoxyphenyl 2-oxazolylmethyl carbonate
3-hydroxy-4-methoxyphenyl 2-imidazolylmethyl carbonate
3-hydroxy-4-methoxyphenyl 2-tetrahydrofurfuryl carbonate
3-hydroxy-4-methoxyphenyl 2-pyrrylmethyl carbonate
Of these, the preferred are those in which the heterocyclic ring is an aromatic heterocyclic ring, e.g., furan, thiophene, thiazole, pyrrole and oxazole.
These novel compounds are effective sweetness agents when used alone or in combination with other sweeteners in foodstuffs. For example, other natural and/or artificial sweeteners which may be used with the novel compounds of the present invention include sucrose, fructose,, corn syrup solids, dextrose, xylitol, sorbitol, mannitol, acetosulfam, thaumatin, invert surgar, saccharin, cyclamate, dihydrochalcone, hydrogenated glucose syrups, aspartame (L-aspartyl-L-phenylalanine methyl ester) and other dipeptides, glycyrrhizin and stevioside and the like.
Typical foodstuffs, including pharmaceutical preparations, in which the sweetness agents of the present invention may be used are, for example, beverages including soft drinks, carbonated beverages, ready to mix beverages and the like, infused foods (e.g., vegetables or fruits), sauces, condiments, salad dressings, juices, syrups, desserts, including puddings, gelatin and frozen desserts, like ice creams, sherbets and icings, confections, toothpaste, mouthwash, chewing gum, cereals, baked goods, intermediate moisture foods (e.g. dog food) and the like.
In order to achieve the effects of the present invention, the compounds described herein are generally added to the food product at a level which is effective to perceive sweetness in the food stuff and suitably is in an amount in the range of from about 0.0001 to 2% by weight based on the consumed product. Greater amounts are operable but not practical. Preferred amounts are in the range of from about 0.0005 to about 1% of the foodstuff. Generally, the sweetening effect provided by the present compound is experienced over a wide pH range, e.g. 2 to 10 preferably 3 to 7 and in buffered and unbuffered formulations.
It is preferred then when the compounds are used in the foodstuff that the compounds have a sucrose equivalent of at least 1 percent by weight, more preferrably that they have a sucrose equivalent of at least 5 percent by weight and most preferrably they have a sucrose equivalent of at least 7 percent by weight.
A taste procedure for determination of sweetness merely involves the determination of sucrose equivalency.
The sucrose equivalence of a sweetener is readily determined. For example, the amount of a sweetener that is equivalent to 10 weight percent aqueous sucrose can be determined by having a panel of tasters taste the solution of a sweetener and match its sweetness to the standard solution of sucrose. Obviously, sucrose equivalents for other than 10 weight percent are determined by matching the appropriate sucrose solutions.
It is desired that when the sweetening agent of this invention is employed in combination with another sweetener the sweetness equivalence of the other sweetener is equal to or above about 1 percent sucrose equivalence. Preferably the combination of sweeteners provides a sucrose equivalence in the range of from about 3 weight percent to about 40 weight percent and most preferably 4 weight percent to about 15 weight percent.
In order to prepare the compounds of the present invention an esterification reaction is employed. A 3-benzyloxy-4-R-oxyphenol is esterified with a chloroformate of the R 1 moiety (e.g., R 1 OCOCl). This provides a 3-benzyloxy-4-R-oxyphenyl R 1 carbonate. This is subsequently converted to the desired 3-hydroxy-4-R-oxy-phenyl R 1 carbonate.
For example, when R is methyl then 3-benzyloxy-4-methoxyphenol is used for the esterification reaction. To obtain 3-benzyloxy-4-methoxyphenol, isovanillin which is also known 3-hydroxy-4-methoxybenzaldehyde is used as a starting material. Isovanillin is a commercially available material. If R is to be other than methyl then the appropriate 4-alkoxy compound is used as the starting material. The 4-alkoxy compound is made by alkylation of 3,4-dihydroxybenzaldehyde which is commercially available. Isovanillin is converted to 3-benzyloxy-4-methoxybenzaldehyde which is then converted to 3-benzyloxy-4-methoxyphenyl formate by the following reactions.
Performic acid is prepared by first heating a mixture of 30% by weight hydrogen peroxide and 97% by weight formic acid in a weight ratio of 1:5 to 60° C. and then cooling the mixture in an ice both. The mixture is then added dropwise over a three hour period to an ice-cold 1M solution of 3-benzyloxy-4-methoxybenzaldehyde in methylene chloride. After the addition is completed a saturated solution of sodium bisulfite is added dropwise until the mixture exhibits a negative starch-iodide test for peroxides. The reaction mixture is poured into an equal volume of water. The phases separate and the aqueous phase is extracted with two parts of methylene chloride per part of aqueous phase. The combined organic phases are washed with water, dried over magnesium sulfate and the solvent is evaporated. The 3-benzyloxy-4-methoxyphenyl formate is recrystallized from 95% by weight ethanol.
The 3-benzyloxy-4-methoxyphenyl formate is then converted to 3-benzyloxy-4-methoxyphenol by the following reaction. A mixture of 3-benzyloxy-4-methoxyphenyl formate, methanol and 1M sodium hydroxide in a weight ratio of 1:6:10 is heated under reflux conditions for one hour, the mixture is allowed to cool and an equal volume of water is added. The solution is washed with ether and acidified to pH 3 with concentrated hydrochloric acid. The resulting mixture is extracted with ether. The combined extracts are washed with water and dried over magnesium sulphate and the solvent is evaporated to yield a tan solid which is 3-benzyloxy-4-methoxyphenol.
The 3-benzyloxy-4-methoxyphenol is reacted with the R 1 chloroformate as follows. The phenol (1.0 equiv.) and triethylamine (1.1 equiv.) are first dissolved in methylene chloride. The R 1 chloroformate (1.1 equiv.) is added and the mixture is stirred for a number of hours. The solvent is then evaporated and the residue is dissolved in a 1:1 mixture of ether and ethyl acetate. This solution is washed with 1M hydrochloric acid, saturated sodium bicarbonate, and water, and dried over magnesium sulfate. The solvent is evaporated to yield the desired product.
The benzyl protecting group is then removed by catalytic hydrogenation. The above product is dissolved in absolute ethanol and 10 percent palladium on carbon is added. The mixture is placed on a Parr hydrogenator, which is then charged with hydrogen to a pressure of 50 lb./in. 2 . Upon the cessation of hydrogen uptake (approximately 2-5 hours) the mixture is filtered through a celite pad and the solvent evaporated to yield the desired product.
Further details are described in McMurray et al. Journal Chemical Society, pages 1491-8 (1960) and Robinson et al. Journal Chemical Society, pages 3163-7 (1931).
The requisite chloroformate of the desired R 1 moiety is either commercially available, known in the art, or prepared from commercially available starting materials by known synthetic procedures.
Chloroformates, in general, can be prepared by the reaction of alcohols with phosgene. For a review of this method, as applied to the synthesis of chloroformates, see Matzner, Kurkjy, and Cotter, Chemical Reviews, 64, pages 645-687, (1964).
The alcohols used for preparation of the R 1 chloroformates (R 1 OCOCl) are known compounds which are commercially available or preparable by standard organic preparative methods.
The synthetic procedures disclosed incorporate the benzyl group as a protecting agent for the phenolic hydroxy moiety during various synthetic reactions. Other groups may be employed in place of the benzyl group to achieve this protection. Examples of these groups include 2-methoxyethoxymethyl, methylthiomethyl, t-butyldimethylsilyl, t-butyl ethers, and the 2,2,2-trichloroethyl carbonate. Other protecting groups, as well as specific reaction conditions and references, can be found in "Protective Groups in Organic Synthesis" by Theodora W. Greene, John Wiley & Sons, NY, 1981, and in "Protective Groups in Organic Chemistry" by J. F. W. McOmie, Plenum Press, London, 1973.
The present new compounds form salts due to the presence of the phenolic hydroxy group. Thus, metal salts can be formed by reaction with alkali such as aqueous ammonia, alkali and alkaline earth metal compounds such as sodium, potassium and calcium oxides, hydroxides, carbonates and bicarbonate. The salts are of higher aqueous solubility than the parent compound and are useful for purification or isolation of the present products.
The following examples are presented to further illustrate this invention.
EXAMPLE 1
3-Hydroxy-4-methoxyphenyl 2-furfuryl carbonate
3-Benzyloxy-4-methoxyphenol (2.3 g.) and triethylamine (1.11 g.) are dissolved in 50 ml. of methylene chloride and the mixture was stirred at room temperature. To the mixture is added 2-furfuryl chloroformate (1.75 g.) and stirring continued for 2 hours. The reaction is quenched with water (1 ml.) and the solvent evaporated to leave a residue which is dissolved in ether and ethyl acetate followed by washing successively with 1M HCl, saturated sodium bicarbonate and water and drying over magnesium sulfate.
The solvent on evaporation yields the corresponding 3-benzyloxy compound which is dissolved in 250 ml. of absolute ethanol with 5% Pd/C, and placed in a Parr hydrogenator with H 2 gas at 50 lb./psi. After hydrogen uptake ceases the mixture is removed, filtered and evaporated to obtain the final product. The structure is confirmed using NMR methods.
The product is sweeter than sucrose.
EXAMPLE 2
A cherry flavored beverage is prepared by mixing 1.48 gms. of an unsweetened cherry flavored instant beverage base mix with 438 gms. of water, 0.13 gms. aspartame (APM) and 30 mgs. (0.007 weight percent) of 3-hydroxy-4-methoxyphenyl 2-furfuryl carbonate. The base contains a malic acid and monocalcium phosphate buffer.
EXAMPLE 3
A vanilla flavored pudding is prepared by mixing 474 gms. of milk, 21.7 gms. of an unsweetened pudding base mix containing 1.35 gms. of sodium acid pyrophosphate, 36.0 gms. sucrose (6.8 weight percent) and 27 mgs. (0.005 weight percent) of 3-hydroxy-4-methoxyphenyl 2-furfuryl carbonate.
EXAMPLE 4
Additional products are prepared using the procedure of Example 1, but substituting 2-furfuryl chloroformate by appropriate chloroformate esters to obtain the following products.
3-hydroxy-4-methoxyphenyl 3-tetrahydrofurfuryl carbonate
3-hydroxy-4-methoxyphenyl 2-thienylmethyl carbonate
3-hydroxy-4-methoxyphenyl 3-theinylmethyl carbonate
3-hydroxy-4-methoxyphenyl 3-furfuryl carbonate
3-hydroxy-4-methoxyphenyl 5-methyl-2-furfuryl carbonate
3-hydroxy-4-methoxyphenyl 5-methyl-2-thienylmethyl carbonate
3-hydroxy-4-methoxyphenyl 5-isopropyl-2-thienylmethyl carbonate
3-hydroxy-4-methoxyphenyl 2-tetrahydrothienylmethyl carbonate
3-hydroxy-4-methoxyphenyl N-acetyl-2-pyrrylmethyl carbonate
3-hydroxy-4-methoxyphenyl 5-acetyl-2-thienylmethyl carbonate
3-hydroxy-4-methoxyphenyl 5-methoxy-2-thienylmethyl carbonate
3-hydroxy-4-methoxyphenyl 3,5-dimethyl-2-thienylmethyl carbonate
3-hydroxy-4-methoxyphenyl 2-thiazolylmethyl carbonate
3-hydroxy-4-methoxyphenyl 5-thiazolylmethyl carbonate
3-hydroxy-4-methoxyphenyl 2-oxazolylmethyl carbonate
3-hydroxy-4-methoxyphenyl 2-imidazolylmethyl carbonate
3-hydroxy-4-methoxyphenyl 2-tetrahydrofurfuryl carbonate
3-hydroxy-4-methoxyphenyl 2-pyrrylmethyl carbonate | Novel 3-hydroxy-4-alkyloxyphenyl heterocyclic carbonates suited as sweeteners in foodstuff, said carbonates having the following basic structure: ##STR1## | 2 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the priority of German Patent Application, Serial No. 101 53 512.0, filed Oct. 30, 2001, pursuant to 35 U.S.C. 119(a)-(d), the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a cooling element with a base plate and several spaced-apart cooling fins which are arranged on a flat side of the base plate. The end faces of the cooling fins together with the formed cooling channels form an inflow and outflow side for cooling air.
[0003] A cooling element of this type is commercially available and illustrated in greater detail in FIG. 1. The cooling element includes a base plate 2 having a flat side 4 and cooling fins 6 , end faces 8 and 10 formed by the cooling fins as well as cooling channels 16 having an inflow side 12 and an outflow side 14 . Cooling air produced by a fan 18 is blown through the cooling channels 16 . The fan 18 is directly attached to the inflow side 12 of the cooling element. Each of the cooling channels 16 is formed by two adjacent cooling fins 16 and a section of the flat side 4 of the base plate 2 . The outflow side 14 is arranged in opposition to the inflow side 12 and is formed by the end faces 10 of the cooling fins 6 and the cooling channels 16 . FIG. 1 does not show the end faces 8 of cooling fins 6 which together with a cooling channels 16 form the inflow side 12 , since these are covered by the fan 18 . Several semiconductor components 22 are mounted with a heat-conducting mounting plate 24 on the flat side 20 of the base plate 2 that faces away from the cooling fins 6 .
[0004] Modern high-efficiency semiconductor devices have a heat flux density of approximately 10 5 W/cm 2 . These devices can be cooled efficiently only by using a cooling element with a high fin ratio R V , which is defined as the quotient of the cooling fin width or thickness R B to the fin spacing R A . The efficiency of the cooling element is limited by the achievable temperature increase ΔT of the cooling air. This temperature increase ΔT depends on the geometry of the cooling element and, more particularly, is proportional to the rib ratio R V . A cooling element with a rib ratio R V =1 has an upper limit value for the increase in the cooling air temperature of approximately 24K as determined by the flow conditions. This increase in cooling air temperature is capable to remove an average heat current {dot over (Q)}.
[0005] The increase of the air temperature in the cooling element is a result of a momentum transfer between the cooling air and the cooled surface at the boundary between the cooling fin 6 and cooling channel 16 , whereby the momentum transfer depends on the degree of turbulence in the flow and increases with increasing degree of turbulence. The degree of turbulence, on the other hand, depends on the surface characteristic of the rib 6 , the physical properties of the cooling air as well as the inherent momentum of the cooling air (airspeed).
[0006] For a given temperature increase and rib characteristic, such as geometry and roughness, the removable heat current {dot over (Q)} can only be increased by increasing the degree of turbulence. This can be achieved, for example, by increasing the airspeed. To achieve this, either the mass flow of the air has to be increased or the cross-section of the flow channel has to be reduced. Both measures necessitate an increase in the required fan power.
[0007] With a constant air mass flow {dot over (m)}, the flow velocity increases with decreasing cross-sectional A of the flow channel, which is equal to the product of fin spacing R A and height of the cooling fins R H . Increasing the flow velocity causes an increased counterpressure in the flow channel. The pressure drop of a flow channel can be expressed by the following equation using Bernoulli's law:
Δ P = ζ * ρ 2 * ( s t ) 2 = ζ * ρ 2 * ( m . ρ * R H * R A ) 2
[0008] As seen from this equation, decreasing the fin spacing R A cause an increase ΔP in the pressure. The form factor ζ describes herein the flow resistance of the flow channel. This form factor ζ is essentially composed of three components, which are:
[0009] a) the surface properties along the flow channel (roughness),
[0010] b) the conditions at the inflow end of the flow channel (geometry), and
[0011] c) the conditions at the outflow end of the flow channel (geometry).
[0012] While for the momentum transfer the form factor ζ along the flow channel should be as large as possible, the components b) and c) listed above and also relating to the form factor ζ are undesirable and detrimental, since they tend to increase the system cost.
[0013] The effect of the form factor ζ in particular of the components b) and c) above, is typically neglected in conventional embodiments of cooling elements. If the heat flow {dot over (Q)} to be removed by the cooling element is to be increased, the pressure drop increases quadratically with the flow velocity and linearly with the form factor ζ. This is a reason why commercially available cooling elements require heavy-duty fans to produce the mechanical power to move the cooling air. However, such fans are large and expensive.
[0014] It would therefore be desirable and advantageous to provide an improved cooling element which obviates prior art shortcomings and which is so configure that a fan requiring less power can be used.
SUMMARY OF THE INVENTION
[0015] According to one aspect of the present invention, a cooling element cooled with cooling air having a flow direction includes a base plate and a plurality of spaced-apart cooling fins spaced apart transversely to the flow direction and arranged on a flat side of the base plate so as to form cooling channels. The cooling fins have end faces which cooperate to form an inflow side and an outflow side for the cooling air. The end faces of the cooling fins on the inflow side and the outflow side are configured so as to provide a low flow resistance. As a result, the fan power can be reduced due to the reduced pressure drop. This advantageous effect increases with decreasing spacing between the cooling fins of a cooling element. The fin density is considered to be high when the fin spacing is approximately equal to the fin width.
[0016] According to an advantageous embodiment of the cooling element of the invention, the spaced-apart cooling fins are offset in the flow direction of the cooling air in such a way that the inflow and outflow sides have a wave-like shape. This measure further decreases the pressure drop and simultaneously reduces the fan power requirement.
[0017] According to another advantageous embodiment of the cooling element of the invention, each end face of each cooling fin on the inflow side is formed convex and each end face of each cooling fin on the outflow side is wedge-shaped. These different configurations of the end faces of each cooling fin gives the cooling fin the shape of an elongated drop that is oriented opposite the flow direction. This produces an ideal form of the cooling fins by reducing the counterpressure, and thereby also the mechanical power requirements of the fan. However, this disadvantageously makes the fabrication process for the cooling element quite complex.
[0018] According to another embodiment of the cooling element of the invention, each end face of each cooling fin on the inflow and outflow side is inclined and/or the spaced-apart cooling fins are mutually offset in the flow direction of the cooling air in such a way that the inflow and outflow side each form a zigzag pattern. The two zigzag surfaces in this embodiment are in phase. This arrangement produces a particularly economical solution for a cooling element according to the invention. By inclining each fin end with the aforedescribed arrangement, a mini-region (each fin) and a macro-region (arrangement of the fins) results, each of which contributes to the reduction in the counterpressure.
[0019] According to yet another advantageous embodiment, each cooling fin can include transverse ribs oriented in the flow direction of the cooling air. In addition, a second base plate can be arranged so that its flat side contacts the narrow sides of the free ends of the cooling fins. At least one the base plate can include spaced-apart grooves oriented in the flow direction of the cooling air, into which grooves a cooling rib can be pressed. For improved heat conduction, the base plate(s) and the cooling fins can be made of extruded aluminum or another metal with a high thermal conductivity.
BRIEF DESCRIPTION OF THE DRAWING
[0020] Other features and advantages of the present invention will be more readily apparent upon reading the following description of currently preferred exemplified embodiments of the invention with reference to the accompanying drawing, in which:
[0021] [0021]FIG. 1 is a perspective view of a conventional cooling element;
[0022] [0022]FIG. 2 shows a flow pattern on the cooling fins of the cooling element according to FIG. 1
[0023] [0023]FIG. 3 shows a flow pattern on the cooling fins of a first embodiment of a cooling element according to the present invention;
[0024] [0024]FIG. 4 shows a flow pattern on the cooling fins of a second embodiment of a cooling element according to the present invention; and
[0025] [0025]FIG. 5 is a perspective view of a third embodiment of a cooling element according to the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0026] Throughout all the Figures, same or corresponding elements are generally indicated by same reference numerals.
[0027] Turning now to the drawing, and in particular to FIG. 2, there is shown a flow pattern of cooling air on cooling fins of a commercially available cooling element according to FIG. 1. The cooling air produced by the fan 18 is depicted in FIG. 2 by arrows A. Also seen in FIG. 1 are on the inflow side 12 turbulent zones B which generate the undesirable counterpressure. This effect increases with increasing width R B of the fins. This effect is particularly pronounced in extruded cooling fins. Turbulent zones C also form on the outflow side 14 of the flow channels 16 due to the movement of the cooling air at the edges of the fin ends. The turbulent zones C can even experience a flow reversal. The flow distribution is a result of the geometry at the inflow and outflow sides of the flow channels 16 . These two components substantially affect the form factor ζ of the cooling element which is responsible for the generation and the magnitude of the pressure drop on the cooling element.
[0028] [0028]FIG. 3 shows the flow pattern on the cooling fins of a cooling element according to a first embodiment of the invention. The sake of clarity, only a few individual cooling fins 6 are shown. The cooling air produced by the fan 18 is also depicted by arrows A. In this first embodiment of the cooling element, the end faces 8 of the cooling fins 6 are convex and the end faces 10 are formed as wedges. The convex form of the end faces 8 of the cooling fins 6 of a cooling element prevent the formation of turbulent zones B at the inflow end of the flow channels 16 , since the cooling air A no longer impinges on a rebounding surface. The cooling ribs 6 are offset in the flow direction of the cooling air A at the inflow side 12 in a wavy pattern. As a result, the convex end faces 8 divert the cooling air A in the region between the end faces 8 into adjacent flow channels 16 . The end faces 8 of the different cooling fins 6 of the cooling element at the inflow side 12 are located on a concave curvature with respect to the flow in cooling air A. The curvature of the concave end faces 8 required for efficiently preventing turbulence depends on the airspeed of the supplied cooling air A. The air mass flow in each flow channel 16 of the fin arrangement of the cooling element can be increased by suitably shaping the end faces 8 on the inflow side 12 . As a result, the airspeed in the flow channels 16 of the cooling element also increases.
[0029] The end faces 10 of the cooling fins on the outflow side 14 of the fin arrangement are wedge-shaped. It should be noted that the wedge-like shape of the end faces 10 should optimally be free of any edges. Advantageously, if the inclined surfaces of the wedge-shaped end faces 10 should be concave. In this way, the cooling air A can exit from the flow channels 16 without experiencing turbulence in spite of the increased airspeed.
[0030] The two end faces 8 and 10 of each cooling fin 6 of the cooling element are formed in the shape of a drop oriented opposite the flow direction. More particularly, the wedge-like shape of the end faces 10 on the outflow side 14 of each fin 6 of the fin arrangement significantly reduced the counterpressure.
[0031] [0031]FIG. 4 shows a flow pattern on the cooling fins 6 of another cooling element according to the invention. The cooling air produced by the fan 18 is also indicated by the arrows A. In this particularly advantageous embodiment, the cooling fins 6 have inclined end faces 8 and 10 . The inclined end faces 8 and 10 of each cooling fin 6 are beveled so as to extend in parallel in space. Moreover, the cooling fins 6 in this embodiment are mutually offset in the flow direction of the cooling air A on the flat side 10 of the base plate 2 so that (the envelopes of) both the inflow side 12 and the outflow side 14 form a zigzag pattern. Since each cooling fin has an identical angle of inclination, the zigzag-shaped inflow and outflow sides 12 and 14 have the same phase. The base plate 2 is made substantially longer (overhang) than that of the cooling element depicted in FIG. 1 so that the flow channels 16 in the inflow and outflow region of the fin arrangement are not entirely open. The angle of inclination (bevel angle) of the inclined end faces 8 and 10 determines the overhang of the base plate 2 . The length of the base plate 2 of the cooling element increases with increasing bevel angle of the end faces 8 and 10 of each cooling fin 6 .
[0032] The aforedescribed advantageous shape of the end faces 8 and 10 of the cooling fins 6 of a fin arrangement of a cooling element produces an embodiment with a substantially reduced counterpressure. Each cooling fin 6 thereby forms a mini-region in the region of the inflow and outflow side 12 and 14 , whereby the arrangement of the fins according to the invention forms a macro-region, which separately contribute to a reduction in the counterpressure.
[0033] [0033]FIG. 5 shows in a perspective view an advantageous cooling element according to the invention. This advantageous cooling element has cooling fins 6 which according to FIG. 4 are arranged on the base plate 2 and have inclined end faces 8 and 10 . The cooling fins 6 are pressed into grooves 26 provided in the base plate 2 . In addition, this cooling element has a second base plate 28 , which is placed with a flat surface on the narrow side of the free ends of the cooling fins 6 . The flat side of the second base plate 28 also has grooves into which the cooling fins 6 can be pressed. The flow channels 16 are closed off by the second base plate 28 , except for the inflow and outflow side 12 and 14 . In addition, high-power semiconductors can be releaseably secured on the flat surfaces 20 and 30 of the two base plates 2 and 28 opposite the grooved surfaces. To increase the surface area of the cooling fin 6 , the cooling fins are provided with transverse ribs extending in the flow direction of the cooling air A.
[0034] By forming the cooling fins 6 in the inflow and outflow region of a fin arrangement of the cooling body according to the invention, the components b) and c) of the form factor ζ can be significantly reduced or even eliminated. This reduces substantially the counterpressure exerted on the cooling air flow, obviating the need for high-power fans 18 , while removing the same heat per unit time {dot over (Q)}. This not only reduces the system cost, but also maintenance expenses.
[0035] While the invention has been illustrated and described in connection with currently preferred embodiments shown and described in detail, it is not intended to be limited to the details shown since various modifications and structural changes may be made without departing in any way from the spirit of the present invention. The embodiments were chosen and described in order to best explain the principles of the invention and practical application to thereby enable a person skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated.
[0036] What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims and their equivalents: | A cooling element includes a base plate and several spaced-apart cooling fins which are arranged on a flat side of the base plate. The end faces of the cooling fins together with the formed cooling channels form an inflow side and an outflow side for cooling air. The end face of the cooling fins on the inflow side and the outflow side are configured to produce a low flow resistance. This substantially reduces the counterpressure exerted on the cooling air flow and thereby obviates the need for high-power fans, without a reduction in the removed heat per unit time {dot over (Q)}. | 5 |
RELATED APPLICATIONS
[0001] This application claims priority from Mexican application Serial No. MX/a/2009/011126 filed Oct. 15, 2009, which is incorporated herein by reference in its entirety.
FIELD OF INVENTION
[0002] The present refers to a washing method, specifically a washing method in automatic washing machines with a basket which rotates concentrically within a tub, where said basket is impelled by a motor, where the washing method itself checks on water level through the cycles, pre-senses the wash load, shakes to readjust, senses the load, shakes normally and shakes to readjust the load.
BACKGROUND
[0003] The present invention relates to the field of household automatic washers, which have recently focused an increasing interest in water consumption, as well as their energy use. This has directed focus on the ability to design various alternatives which allow for rational use of this vital liquid, as well as rational use of energy. On the other hand, some types of washers, like for example front loading washers, since they use small amounts of water, in many cases have compromised the efficiency of stain removal, where the wash cycle is longer, or being forced to use some means to elevate water temperature (a process which itself consumes high amounts of energy), in order to maximize the chemical power of the detergents or other additives mixed with the water to create the washing mixture.
[0004] Said front loading or horizontal axis washers face the above described problems, where water consumption is reduced in comparison with top loading or vertical axis, they undergo much longer cycles as well as the need to heat up water, thus increasing energy consumption. Since they are not fitted with an agitator or propeller, large water flows are not created which would have the ability to permeate through the weave of the articles to be washed, and since it is also not fitted with scrubbers, the scrubbing effect does not take place, thus their surfaces do not create friction with the objects to be washed. The above mentioned front loading or horizontal axis washers, similarly require some ties grasped unto the length of the cylinder or basket which aid in turning and mixing the clothes, causing friction between said clothes as well as against the referred to ties and the basket's interior surface. These significant differences, on one hand cause the wash cycles in a front loading or vertical axis washer to be longer cycles, it being evident due to low friction amongst the objects to be washed that there is less wear on them, which makes the removal of spots or dirt adhered to the fibers of the weave more difficult, with the understanding that low flow currents of the water or the washing mixture which cross said weaves in the cloth, coupled to the low friction among the same clothes, thus resorting to the chemical action of the washing mixture, which in order to maximize said detergent action, the washing mixture is heated and the wash cycle lengthened in order to attain a good washing action on the textiles or objects to be washed.
[0005] On the other hand, the top loading or vertical axis washers require high amounts of water so that the agitator or propeller can create good water flow, which coupled to the scrubbing action of the propeller or the agitator, cause friction unto the surface or weave of the objects to be washed added to the chemical action of the detergents which aid in removing spots firmly adhered to the textile fibers. This system allows for shorter washing cycles with less energy consumption but with higher water consumption.
[0006] Therefore, there exists the need for new technology which: should have low water consumption and low energy consumption, create strong water flow currents which aid in the penetration of the washing mixture through the fibers of the weave, vigorous scrubbing of the articles to be washed without damaging them, allow for the mixing of water and chemicals before the latter have any contact with the objects to be washed, which helps among other things, to begin the chemical action quickly when the mixture is homogenized, thus taking advantage of its chemical action to attain high washing efficiency. These reasons cause the thinking of a vertical loading washer which has a particular agitator or propeller, which allows washing with a low water volume. Also, there should be a washing method which aids in energy conservation, as well as efficient wash, these being among others, the objective of the present invention.
[0007] Various efforts have been made with the aim of reducing water and energy use in household washers, as is the case in Pastryk's et al U.S. Pat. No. 4,986,093, which describes a recirculation system, which is composed of a tank which mechanically adheres to the washer's tub. Said tank receives the detergent or chemicals as well as a certain water volume, the tank serves to mix the detergent with the chemicals, so that these may be poured in shower fashion unto the articles to be washed. This solution has the inconvenience of using high water volumes for the wash cycle, knowing that this takes place in traditional form, that is: the tub is filled to a certain water volume, the objects to be washed being totally immersed in the above mentioned liquid, followed by the beginning of the agitation cycle, with the variant that before said agitation, the mixture or washing mixture contained in the tank is pumped towards a nose or shower spraying the objects to be washed with the washing mixture. As can be seen, this method and tank arrangement do not contribute in great measure to substantial water nor energy savings, but indeed serve as a base for future developments, knowing that mixing water with chemical detergents before these make contact with the objects to be washed, avoids an undesired chemical attack on the textiles and betters the mixing proportions for a more uniform washing mixture, coupled to this aiding the objective of the detergent or chemicals in the wash.
[0008] A second example is Kretchman et al's EP 668 389 A1, which presents an improvement over the document above mentioned. Specifically, the space created in the lower part of the basket and the tub's bottom has been taken advantage of to store water, same which, once having a determined liquid level in this said area, detergent or washing chemicals are added, mixing to form the washing mixture, by means of a pump placed in a trough and hoses, the washing mixture is extracted and sprayed on the basket's upper part, meanwhile the bottom of the basket rotates with one or two degrees of liberty. Once again, it can be seen that if the water storage improvement in the tub's bottom is of great help, the circular and undulating movement of the basket's bottom, far from helping would be more of an artifact found at a fair. However, this does not represent an improvement with the purpose of stain or dirt removal on the objects to be washed.
[0009] Thus, in view of the problems described above, coupled to higher social conscience on the part of the consumer regarding more efficient household appliances, with more options, low cost, dependable and in particular with lower water use, the present invention has been developed.
BRIEF DESCRIPTION OF THE INVENTION
[0010] The high efficiency washing method of the present invention has the peculiarity of adapting to different washing conditions imposed by varying washing habits of the operators. So that in the washing sequences, instead of emitting a failure signal, it is always intent on continuing the washing cycle, avoiding complaints and hassles for the operator in situations like for example: overloading the articles to be washed in the washer, clothing types, additives which create too much foam, unbalancing due to larger articles etc.
[0011] The cycle of the preferred embodiment of the invention begins when the operator has introduced a determined amount of articles to be washed, optionally, a determined amount of additives for the wash, has selected a program to use and the washer has been turned on, which in turn initiates a sequencing of pre-sensing of the load, where the washer indicates if there are an excess of clothes or a load which in a preferred embodiment is reported greater than 7 kg; if no overload condition is detected the bleach admission valve is opened for a determined time to later start with the reshuffling sequence and later do a water spraying contained in the bottom of the basket to hydrate the exposed objects to be washed which are placed on the top, or in the opposite case, upon detecting the overload, the mechanical control omits the reshuffling sequence and proceeds directly to the load sensing sequence. The mentioned load sensing sequence takes place in order to determine in a more precise fashion than the load pre-sensing sequence, the amount of objects to be washed which are placed in the basket. In this way, the amount of water can be properly determined, and in a preferred embodiment of the present invention, the centrifuge pattern as well as the rinsing blocks or the required rinsing profile with the purpose of saving water. Once the sensing the amount of articles to be washed in the basket, in order to determine the wash level takes place, the overload possibility is checked again. If said overload condition does exist, an agitating sequence begins at the maximum charge with a level V or water maximum so that later the dehydrating and rinsing phases take place. In an opposite case, if there exists no overload condition, water is introduced until the predetermined level is reached (level II or minimum, level III or medium, level IV or high), beginning the sequence of normal agitation for a predetermined time, to later undergo the reshuffling sequence for another determined time. Subsequently, the dehydration takes place to ultimately rinse the objects to be washed deposited in the basket, thus finalizing the complete wash cycle.
[0012] Thus, as can be seen, this novel washing method is efficient both in energy and in water usage. Additionally, it has sequences which allow for the continuity of function in case excessive overload exists, or jamming of the articles to be washed, tangling, overloading or any other problem which can occur when washing textiles in a washing machine.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a cross section of a washer.
[0014] FIG. 2 is an upper view of a sub-washer, that is, a washer without cabinet.
[0015] FIG. 3 is an isometric cross section of a sub-washer.
[0016] FIG. 4 is a flow diagram of the high efficiency washing method of the present invention.
[0017] FIG. 5 is an electric diagram of the components which the high efficiency method of the present invention requires.
DETAILED DESCRIPTION OF THE INVENTION
[0018] The washing machine object of the present invention, which is shown in FIGS. 1 , 2 , and 3 is of the top loading or vertical axis type, having a cabinet from which four suspension bars 12 are fastened to. Said suspension bars 12 support the weight of the tub 11 as well as the remaining accessories of the referred to cabinet, as well as acting as shock absorber to the vibrations which originate during the washing process. Thus the tub 11 is hanging from said suspension bars 12 by means of some ears placed in the lower part of said tub 11 . Over the referred to tub 11 the remaining periphery equipment is mounted, such as the motor 21 , optionally a planetary gear for reduction, which in an alternative embodiment to the present invention can be omitted, adjusting the relationship between the pulleys 22 , that is, the pulley 22 with the greatest diameter will be adjusted over the inner shaft 25 which will receive energy originating from the electric motor 21 thanks to the pulley arrangement 22 and the strip. Optionally, the shaft 25 on its extreme upper part is coupled to a planetary gear 24 , with the purpose of reducing angular velocity and thus gain greater par, the exit shaft of the planetary gear 24 will reintegrate into a shaft 25 , which on its upper part has the agitator 13 assembled. Optionally, the inner shaft 25 on its lower part is coupled with the pulley 22 with the greatest diameter and on its extreme upper part is coupled to the agitator 13 . The hollow shaft 26 houses in its interior the inner shaft 25 . Said hollow shaft 26 is mechanically coupled to a clutch 28 which can cause both shafts 25 , 26 to rotate together or independently. Said hollow shaft 26 is mechanically coupled to the basket's center or hub 32 , so that when shafts 25 , 26 are clutched and rotating together, the hollow shaft 26 will transmit energy to the basket 10 so that it may spin together with the agitator 13 .
[0019] The basket 10 is crowned by a balancing ring 27 which counteracts the unbalancing caused by the shifting inside the basket 10 of the objects to be washed. The tub itself has assembled unto its extreme upper part a tub cover 14 which houses a grid 19 as well as a spray deflector 18 . The cabinet itself is covered by the main cover 30 which covers the upper part of the washer 20 . Said main cover 30 helps support a crest 31 which houses the electric components such as the control 40 , the drivers 71 thru 79 , the pressure switch 41 etc as well as the washer's door or lid 29 through which the articles to be washed are placed.
[0020] FIG. 5 shows detail of the connection between the electric control to the various sensors or actuators which it controls, which allows for the washer's 20 proper functioning as it sends signals to the various actuators at the times determined by the method object of the present invention. Thus the electric motor 24 is energized by a driver 72 which receives signals from the electric control 40 . The referred to electric control 40 sends a pulse with a certain longitude to the driver 72 so that it, during the time that said pulse longitude lasts; it energizes the motor 24 in a certain direction. The same can occur to energize the motor 24 in the opposite direction, waiting for a determined time between swats or pulse widths.
[0021] The high efficiency method of wash, object of the present invention referred to on FIG. 4 , begins when the operator has introduced a determined amount of articles to be washed, in its case a determined amount of wash additives, has selected the program to be used and has started the washing machine. Thus, the electric control 40 first checks if the signal which it receives from the pressure switch 41 indicates if the water level is greater than the spray level or level I, should this occur, the sequence of load sensing 65 begins, or in the opposite case, a sequence of load pre-sensing 63 takes place, a sequence which will be later detailed. This indicates whether there is an excess of clothes or load, for example in an illustrative form but not limited form, greater than 7 kg. If such an overload condition is not detected, the electric control 40 activates the agitating sequence 64 to reshuffle clothes which will be later detailed. In an alternative modality, a spray sequence 66 takes place at certain intervals in intermittent form, which shall be later detailed. During the rest of the washing cycle or during the agitating sequences 60 , 61 , 62 , 67 this takes place with the objective of hydrating the objects to be washed which are exposed or that are found on the top. In case overloading is detected, the electric control 40 omits the agitating sequence of reshuffling 64 and proceeds directly to the load sensing sequence 65 . The referred to sensing sequence 65 , which shall be detailed later, takes place in order to be able to determine in a timely manner versus the pre-sensing of load sequence 63 the amount of objects to be washed which are placed inside the basket 10 , thus being then able to determine the proper amount of needed water according to the objects to be washed which are placed in the basket 10 . In a similar manner at this point the possibility of overload condition is checked on again. Should this exist, a second agitating sequence 62 at a maximum load takes place, which shall be later detailed, with a maximum water level or level V of water or washing mixture to later undergo the dehydrating and rinsing phases. In the opposite case, when the overloading condition does not exist, water is introduced to a predetermined level, such as level II or minimum, level III or medium, or level IV or high in light of the electric control 40 's sending a signal to the driver 78 of the filling valves 45 , so that these may allow the water to enter towards the tub 11 . This can take place until the electric control 40 receives the proper signal that the water level determined by the pressure switch 41 (level II or minimum, level III or medium, level IV or high) has been attained. When it reaches said level, the signal to the driver 78 to the filling valves 45 stops, thus ceasing the flow of water into the tub 11 . As soon as the proper water level is reached, the electric control 40 begins the normal agitating sequence 60 for a determined amount of time which preferably varies between 5 and 30 minutes. Once this time elapses, the agitating sequence of reshuffling 64 takes place for another period of determined time which varies between 1 and 20 minutes. Once said time interval elapses, dehydrating 69 takes place in order to ultimately go to rinsing 70 phase of the objects to be washed which are placed inside the basket 10 .
[0022] In an alternative embodiment of the present invention, rinsing 70 can count on a centrifuge pattern which includes rinsing blocks or have a required rinsing profile with the intent of saving water, thus ending with this step the complete washing cycle.
DEFINITIONS
[0023] Arc. Angular distance which the agitator or propeller 13 is displaced which is measured in degrees from its resting state until it returns to its resting state.
[0024] Desired Arc. The desired angular distance which the agitator or propeller should be displaced while the motor 21 is energized.
[0025] Arc Measurement. Takes place in the preferred embodiment of the present invention by means of a rotor position sensor, preferably a hall type 44 installed on the motor 24 , which reports a determined number of pulses to the electric control 40 each time the motor 24 is activated in each direction, the referred to number of pulses is directly proportional to the longitude of the arc, thus the number of pulses can be referenced according to any given arc longitude. Thus the electric control 40 compares the pulses measured by means of the rotor's position sensor 44 via shocks or swats versus a determined range of aim of pulses.
[0026] Swats. The agitator's or propeller's 13 circular movement in clockwise or antic-clockwise direction during a period of determined time: this is attained when the clutch 28 is found in agitating motion, the electric control 40 starts the counting of time with an inner timer and at the same time sends a signal to the motor's 21 driver 72 so that it may energize the motor 21 thus prompting the agitator or propeller 13 which will then described a determined arc which is measured thanks to the rotor's 44 position sensor, knowing that the latter sends a string of pulses to the electric control 40 which counts them, as said electric control 40 has a reference directly proportional between number of pulses counted and the arc described by the agitator or propeller 13 , so that when the electric control 40 senses it has reached the desired arc, the signal to the motor's 21 driver 72 is interrupted and stops the time counter of the inner timer, knowing that the agitator or propeller 13 in order to effect its displacement and follow the trajectory of the desired arc has a specified time, if this time lapses before the agitator or propeller 13 finishes its angular displacement, the electric control 40 will begin a determined waiting time counting period which varies between 0.01 seconds to 5 seconds, once the condition of angular displacement or the course of time has taken place, said waiting time shall have to take place before beginning a new swat in the opposite direction to the one immediately previous.
[0027] Stroke per Minute. SPM, according to its initials, refers to the number of continued swats in both directions achieved in one minute, including the waiting time between swats.
[0028] Agitation. Movement which is obtained on the objects to be washed by the action of the agitator or propeller 13 on the first objects immersed in the washing mixture.
[0029] Desired arc with normal agitation. Has an arc longitude which varies between 180 to 1100 degrees with a frequency between 30 and 60 strokes per minute (spm).
[0030] Clog. According to the arc measurement if it is found that the arc of one swat is significantly less than the agitation desired arc, the electric control 40 , it is assumed that a clog exists, which implies that some object to be washed is jammed and has clogged the agitator or propeller 13 or that a high concentration of objects to be washed exists with a reduced volume in the basket causing an undesired high concentration of objects to be washed in a particular area within the basket 12 .
Normal Agitation Sequence 60
[0031] The normal agitation sequence has a pattern of swats or arcs (turns of the agitator 13 in both directions—clockwise and anti-clockwise), strokes per minute (spm) or number of times which it turns each side per minute and the time of agitation.
[0032] The determination of the arc is a function of the liquid density of the wash clothes, transmission of potency and the motor 21 capacity in terms of torque availability.
[0033] The desired arc of normal agitation varies between 180 to 720 degrees obtaining anywhere between 30 to 60 strokes per minute (spm) said arc allows for proper friction between the scrubbers of the agitator 13 and the objects to be washed, it also contributes to better dispersion of the objects to be washed within the basket 12 , with the end result that these have adequate movement of the articles to be washed. A lesser arc would imply that one of the articles to be washed has been caught or that an unusual and undesired accumulation of objects to be washed has occurred in the basket, creating a high density of objects to be washed in a reduced volume within the basket 12 , which then causes the agitator's 13 scrubbers to not be in contact with the objects to be washed, thus creating decreased friction among these and thereby creating less dirt removal. These being, coupled to other motives, so that at all times it is being sensed in order to attain the desired arc with each stroke or swat, since as was previously discussed an arc out of range is undesirable, it is desirable to take actions directed towards a better distribution of articles to be washed within the basket 12 as is the case in the high density agitating sequence 67 or the maximum load agitating sequence 62 so that each stroke or swat is monitored comparing its length of arc versus the length of the desired arc. Said measurement of arc takes place in the preferred embodiment of the present invention by means of a position sensor of the rotor 44 installed in the motor 24 , which reports back a determined number of pulses to the electric control 40 each time the motor 40 acts in each direction. The number of pulses referred to is proportional to the length of the arc so that a determined number of pulses can be referenced to a given arc length. Thus the electric control 40 compares the pulses measured by strokes or swats versus a determined range of desired pulses, if the value measurement is within range agitation and strokes or swats will continue conventionally, but if the opposite is true upon detecting a shorter arc than the desired arc of normal agitation, the electric control 40 concludes that a clog exists, thus activating the high density agitation sequence 67 which shall be later detailed. Said high density agitation sequence 67 uses a position sensor of the rotor for a determined time a reduced arc, which in a preferred embodiment can return to the desired arc of normal agitation described above. Once the agitation time is concluded which continues running its course with the various determined efforts by the proposed method with the objective of uniformly segregating the clothes within the basket 12 .
Agitating for Adjustment Sequence 61
[0034] This special sequence of agitation has as a purpose the diffusing or disseminating of the objects to be washed within the basket 10 in a uniform fashion within the volume of work contained within the basket 10 , to avoid as much as possible, the unbalancing in the dehydrating or centrifuge stage. The basket 10 in said centrifuge stage turns at high revolutions, always having the objects to be washed within the basket 10 as evenly distributed as possible within the working volume, avoiding clumps or high density of clothes in a reduced volume which could cause an unbalancing within the basket 10 . The clutch thus being in agitating manner the electric control orders a swat with a desired arc between 400 and 500 degrees, with a frequency such that between 30 and 60 strokes (or swats) can be reached per agitation minute, for a period between 1 and 20 minutes.
High Load Agitating Sequence 62
[0035] This high load agitating sequence given the peculiar characteristics of the agitator or propeller 13 requires special conditions in order to take place. Thus in case the operator has introduced a high load of objects to be washed into the basket 10 which create an overloaded condition, the referred to objects will be able to be washed without major complication using a special pattern of distribution. On the other hand, this pattern is also focused on protecting the mechanism of the washer 20 itself, since this pattern requires a lesser effort from the motor 21 , avoiding over-heating, and additionally reducing the mechanic efforts between the pulleys 22 , the band 23 and the shafts 25 , 26 among others. Thus the electric control 40 uses a swat with a desired arc varying between 50 and 180 degrees with a frequency varying between 10 to 30 strokes (or swats) per minute, maintaining these oscillations for a determined period of time between 5 and 20 minutes.
High Density Agitation Sequence 67
[0036] This sequence takes place within the sequence of normal agitation. As was discussed in the normal agitation sequence 60 , in case of detecting an arc which is lesser than described by the agitator or propeller 13 to the desired arc of normal agitation which varies between 180 and 1100 degrees attaining between 30 to 60 spm, would imply that an object to be washed has become clogged or an unusual and undesired accumulation of objects to be washed is present thus creating a high density of objects to be washed in a reduced volume within the basket 12 . The ensuing causes the scrubbers of the agitator 13 to not be in contact with the objects to be washed creating lesser friction among these and allowing for minimized dirt removal. Thus it is desirable to take actions aimed at better distribution of objects to be washed within the basket 12 as would be the activating the high density agitating sequence 67 or the high load agitating sequence 62 . This being the case, each stroke or swat is monitored comparing its arc length versus the desired arc length, if based on the result of the comparison of the latter two a significant difference is noted, the electric control 40 assumes that a clog is present which means that an article to be washed has been caught or clogged the agitator or propeller 13 so that a high concentration of objects to be washed in a lesser volume within the basket is present, causing an undesired high density of objects to be washed in an area within the basket 12 . Were the normal agitation 60 to continue we run the risk that said undesired high density of objects to be washed will increase or the clogging of the propeller 13 or agitator worsen, so that the idea of a high density agitating sequence 67 which allows in the majority of cases to dissolve said undesired high density of objects to be washed or to remove the offending articles which caused the clog to the agitator or propeller 13 . Thus when the electric control 40 detects a great difference between the measurement of the arc and that of the desired arc (a stroke with a shorter arc than the desired arc) it is supposed that a clog exists, which activates the before mentioned high density agitation sequence 67 . This has swats with a desired arc which varies between 70 and 110 degrees with a frequency between 50 and 70 strokes per minute thus obtaining vigorous agitation with a reduced displacement or arc of the agitator or propeller 13 , this manner of agitation with swats with a reduced desired arc takes place for a determined time which varies between 1 and 20 minutes, depending on the parameters of design of the agitator or propeller as well as those of the basket 10 . This time of normal agitation having lapsed, the electric control 40 reestablishes the swat with the desired arc of normal agitation using the normal agitation sequence 60 . In an alternative embodiment of the present high density agitation sequence 67 the desired arc varies between 70 and 110 degrees and can increase with each swat a fixed value which varies between 4% and 10% of the value of said desired arc, this occurs until the desired arc is the same or almost similar to the desired arc of normal agitation. So that when the electric control 40 detects by means of the count of emitted pulses by the rotor's 44 position sensor that the desired arc of normal agitation used in the normal agitation sequence 60 has been reached it continues with the referred t normal agitation sequence 60 . Yet in another preferred embodiment to the present high density sequence 67 , the desired arc varies between 70 and 110 degrees and can increase by a fixed value which varies between 4% and 10% of the value of the objective previously mentioned for periods of determined time which can vary from 5 to 60 seconds. Thus when the period of time lapses, the value of the reduced arc is increased, thus begins a new determined period of time. This occurs until the desired arc is equal or close to equal to the desired arc of the normal agitation using a normal agitation sequence 60 . Thus when the electric control 40 detects thanks to the count of emitted pulses by the rotor's 44 position sensor, that the desired arc of normal agitation used in the normal agitation sequence 60 has been reached, it continues with the normal agitation sequence 60 referred to.
[0037] If the electric control 40 by means of measurement of the arc detects another clog in an alternative embodiment of the present invention it can begin to undergo the sequence described above a set number of times preferably between 1 and 5 more times.
[0038] When the electric control 40 by means of measurement of the arc detects another clog having at least undergone the agitation sequence 67 described above at least one time, the washing mixture is increased by means of introduction of fresh water, this is done with the intent of providing a n increased volume of washing mixture within the tub 11 which provides a greater work mass volume within the basket 10 , since the articles to be washed can move with greater ease within a greater mass volume of washing mixture. Thus when the electric control 40 detects a new clog within the normal agitating sequence 60 , the electric control 40 verifies by means of the pressure switch 41 the level of washing mixture in the tub 11 . If this is equal or greater than the maximum level or level V, the electric control 40 activates the high load agitating sequence 62 previously thoroughly described. If the opposite is true, the electric control 40 sends a signal to the driver 78 so that this in turn energizes the filling valve 45 , thus allowing the flow of water towards the tub 11 , this occurs until the pressure switch indicates that the next level of water or washing mixture has been reached, at which point this causes the electric control 40 to quit signaling the driver 78 , de-energizing said filling valve 45 and thus interrupting the flow of water towards the tub 11 . Afterwards, the electric control again begins the normal agitation sequence 60 for the remaining time left on the normal agitation sequence 60 .
Pre-sensing of Load Sequence 63
[0039] This sequence is based on a measurement of inertia of the basket 10 itself. When the basket 10 is empty its inertia is less than the inertia measured when the basket is loaded with objects to be washed. The pre-sensing of load sequence helps determine whether an over-load condition exists, that is, for example, in illustrative but not limited form, when the operator has placed in the basket 10 a load or objects to be washed greater than 7 kg and this condition is detected, the electric control 40 does not use the reshuffling of clothes sequence which shall be detailed later, knowing that the high density of the objects to be washed within the basket 10 in the case of sensing overload condition, does not allow for the objects to be washed to accumulate (or compress) in particular or specific areas within the basket 10 , thus resulting unnecessary and counterproductive to use a re-shuffling of load sequence going directly to the agitating sequence. Thus the sensing of overload occurs once the operator has introduced the objects to be washed into the basket 10 . Given that the clutch 28 is in centrifuge form, the operator, upon pressing the start button, sends a signal to the electric control 40 which initially recuperates a signal from the pressure switch 41 to then be able to determine the proper level of washing mixture or water within the tub 11 . If the washing mixture or water level is greater than level I, the electric control will not undergo the pre-sensing of load sequence, instead going directly to the agitating sequence, but if the opposite is true, if there is no washing mixture or water within the tub 11 or if the level is the same or lower than that of level I, the electric control 40 sends pulses of 100 ms to 700 ms to the motor's 21 driver 72 so that this may energize the motor 21 , keeping in mind that the clutch is in dehydrating form and will cause both the basket 10 as well as the agitator or propeller 13 move in unison, given that the inner shaft 25 is clutched to the hollow shaft 26 , thus both the basket 10 as well as the agitator or propeller 13 will turn in one direction for a given time, this time comprising two components, the first being the duration of the pulses emitted by the electric control 40 to the motor's 21 driver 72 and the second component is determined by the inertia, since the time it takes the basket to reach resting position describing: this is also a length of arc which directly depends on this second component. Thus the motor's 21 rotor's 44 sensor position sends a pulse through the length of the determined arc. Said pulses emitted by the rotor's 44 position sensor are sent to the electric control 40 which keeps a count on them. Thus a determined number of pulses are proportional to a certain length of arc or with a deceleration time of the basket's 10 . Thus the pulses emitted by the rotor's 44 position sensor placed in the motor 21 are counted from the point in which the motor 21 is de-energized for a set period of time (preferably approximately 15 milliseconds) and allow for the detection of overload condition. In this way, the number of pulses emitted by the rotor's 44 sensor position within a set period of time can be stored in said electric control's 40 memory which enables it to later compare to a set value, which if it is the same or greater indicates the existence of an overload condition which is also stored in the electric control's 40 memory. Thus once the basket 10 is once again in resting state, the electric control once again emits a new pulse in opposite direction to the previous pulse emitted to the motor's 21 driver 72 , this last one causing the basket 10 and the agitator or propeller 13 to turn in the opposite direction of the pulse immediately before it received for a determined amount of time, which in similar fashion to the pulse previously emitted by the electric control 40 to the motor's 21 driver 72 will have two components, the first being the time or width of pulse which keeps the motor 21 energized and the second component being the deceleration time. Once again the number of pulses emitted by the rotor's 44 sensor position to the electric control 40 is counted in a set amount of time which preferably varies between 200 and 990 milliseconds. Similarly, the number of pulses counted by the electric control 40 emanating from the rotor's 44 sensor position in a determined amount of time is counted and is compared to a set value. If this is equal or greater, then an overload condition exists and these values are stored in the electric control's 40 memory. Thus, if the result of the pulse emitted just previously by the electric control 40 to the motor's 21 driver 72 or the actual, cause an overload condition, the electric control 40 considers this as a real overload condition, consequently omitting the re-shuffling of clothes sequence 64 and proceeds directly to the sensing of load sequence 65 , in the opposite case, the electric control 40 begins a reshuffling of load sequence 64 .
Re-Shuffling of Clothes Sequence (Donut) 64
[0040] This sequence helps to uniformly distribute the objects to be washed within the basket 10 , avoiding the concentration of objects to be washed accumulating in a small space, which cause high density of objects to be washed or accumulations of objects to be washed within the basket 10 , hindering efficient contact with the agitator or propeller 13 , which cause an undesirable movement of objects to be washed within the basket 10 since proper flow of washing mixture generated by the agitator or propeller 13 is not possible, and consequently the flow of washing mixture through the fibers of the objects to be washed do not have enough force, consequently reducing the effectiveness of the wash. It is for these reasons, coupled to others, that it is desirable to carry out an efficient reshuffling of clothes within the basket 10 previous to the agitating sequence with the purpose of attaining a better washing condition of the objects to be washed taking into consideration a moderate or low water level. After undergoing the load pre-sensing sequence and having determined from the electric control 40 that an overload condition does not exist, the basket 10 being in resting stage, the electric control 40 sends a pulse which varies between 8 and 12 seconds to the driver 78 of the filling valve or water admitter 45 to allow the flow of fresh water into the interior of the tub 11 , which, in an alternative embodiment of the invention, can be hydraulically connected to the chemical dispenser 34 , also sending the electric control 40 a pulse for the same time lapse to the driver 74 of said chemical dispenser, and yet, in another alternative embodiment of the invention, the electric control 40 sends a pulse for a determined amount of time to the whitener liquid admission valve 46 , so that it allows the admission of this liquid in case the operator has deposited a certain whitener liquid volume in the corresponding chemical dispenser 34 compartment. Thus, when the admission valve of the liquid whitener 46 opens, a certain volume of water is allowed in, which is transported through the chemical dispenser 34 , dragging with it the volume of bleach which was placed in the chemical dispenser 34 , which then directs the washing liquid so that in a waterfall form, it falls through the buffer on the mesh 19 , which allows the washing liquid to pass between the tub 11 and the basket 10 , avoiding contact with the objects to be washed, thus depositing the washing mixture in the tub's bottom which allows for uniform mixture of the chemicals with the water without directly pouring the chemicals unto the objects to be washed which can cause spotting due to chemical attack on the surface of the objects to be washed due to poor dilution and consequent chemical mixture with the water.
[0041] Once the mentioned width of pulse is lapsed, the electric control sends a pulse which varies between 2 and 20 seconds to the pump's 15 driver 71 , which allows it to replenish the washing mixture during the width of said pulse to the spray deflector 18 spraying the objects to be washed placed inside the washing cone of said pray deflector 18 with the washing mixture. Once the duration of said pulse is expired, these steps are repeated for a determined amount of time which varies between 30 and 60 seconds, or at least one basket 10 revolution, so that the objects to be washed placed in the basket 10 are soaked with the washing mixture which had accumulated in the tub's bottom 11 . Followed by, once all or the majority of accumulated water volume has been transferred from the tub's bottom 11 to the objects to be washed, the electric control 40 sends a pulse which varies between 5 and 15 seconds to the motor's 21 driver 72 , keeping in mind that the clutch 28 is placed in dehydrating fashion; this allows the basket 10 to rotate the objects contained in the basket 10 , where when rotating at a certain velocity for a certain amount of time, the washing mixture is extracted from the textiles, and collects at the bottom of the tub 11 . When the basket is rotating, the rotor's 44 sensor position sends a set of pulses to the electric control 40 , and this in turn determines the velocity at which the motor turns thanks to its internal logic. Thus, when the motor reaches a velocity which varies between 90 to 150 rpm, the electric control de-energizes the motor's 21 driver 72 causing the immediate deceleration of the basket 10 until the basket reaches its resting position, having detected this condition, the electric control 40 , thanks to the absence of pulses of the rotor's 44 sensor position, in an alternative embodiment of the present invention, the steps to this sequence are repeated at least one time.
Sensing of Load Sequence 65
[0042] The purpose of this sequence is to determine by means of a particular agitation pattern the quantity and type of objects to be washed, so that as a function of resistance which said load opposes the movement of the agitator or propeller 13 , it defines the water levels corresponding to agitation during the washing phases, the centrifuge pattern and the number of rinsing blocks.
[0043] This sequence operates in two ways, the first being when the electric control 40 does not register an overload condition, the second when the electric control 40 detects an overload condition. In the first instance, when no overload exists, the electric control 40 in some way has to measure in a qualitative way, the amount objects to be washed within the basket 10 , to be able to determine the water level, and to use during the agitation sequence, the number of rinsing blocks, as well as the profile of centrifuge ramps in the dehydrating sequence. Thus the ingenious development of the present sequence was devised without the need to use more sensors than the motor's 21 position sensor 44 . In this way, the mentioned sequence begins when the electric control 40 checks on the possibility of overload existence, and upon not finding such condition (first instance) it sends a signal to the filling valve's 45 driver 78 , so that these allow the flow of water into the tub 11 to be stored in the tub's bottom, this condition persists until the pressure switch 41 sends a signal to the electric control 40 that the minimum level or level II has been reached, keeping in mind, that the clutch 28 is in agitating form, when said minimum level or level Ii is reached the electric control 40 stops the signal to the filling valve's 45 driver 78 , now sending a signal to the motor's 21 driver 72 . Simultaneously, the electric control 40 keeps count of the pulses sent by the rotor's 44 position sensor thus measuring the arc, with a desired arc varying between 180 to 72 degrees with a frequency varying between 20 to 60 spm until a certain number of strokes or swats are counted, like for example, between 10 and 40 strokes or for a determined period of time, which preferably varies between 30 to 50 seconds. This period of time having transpired, agitation continues with a desired arc varying between 180 to 720 degrees, counting a certain number of strokes which can preferably vary between 10 and 40 or for a second period of time which preferably lasts between 20 to 40 seconds. It is during this second period of time, where after each swat takes place or rotation which varies between 180 to 720 degrees, where the electric control 40 , upon detecting that the rotation angle mentioned above has been reached and the signal to the motor's 21 driver 72 has been interrupted, that it begins counting the pulses sent by the rotor's 44 position sensor until the agitator or propeller 13 reach their resting position, which causes an interruption in the set of pulses which the rotor's 44 position sensor sends the electric control 40 . Thus the electric control 40 with each swat or angular path, registers the number of pulses which the rotor's 44 position sensor has sent while the motor 21 is de-energized, said fact is stored in said electric control's 40 memory, next to the fact of the swat or angular path immediately following in the opposite direction. This set of facts is continually being averaged and stored in the memory so that each swat or angular path followed is averaged with the subsequent one, erasing the facts from the previous set of swats. This takes place until the second period of time has lapsed, and when this takes place, the last fact is averaged remains in the electric control 40 and is compared with predetermined values which indicate the water level to be used. This is followed by the electric control 40 sending a signal to the filling valve's 45 driver 78 until the determined water level for the load of objects to be washed has been reached, thanks to the signals which the pressure switch sends the electric control 40 .
[0044] In the second scenario, if it is confirmed that an overload condition does exist in the load pre-sensing sequence, the electric control 40 begins the high load agitation sequence 62 .
Spraying Sequence 66
[0045] This sequence serves as an alternative embodiment to the washing method, object of the present invention. The sequence takes place in the agitating sequences or while the clutch is in an agitation form in the following way: taking into account that within the tub 11 a certain volume of washing mixture is present, having been detected by the pressure switch 41 which in turn sends a signal to the electric control 40 , if said level of washing mixture or volume of washing mixture is greater than or equal to the minimum level or water level II, the electric control 40 sends a pulse for a determined period of time which can vary between 0.5 seconds to 2 seconds to the driver 71 of the spray pump 15 so that it may in turn send water to the spray deflector 18 via the spray hose 17 so that in it may dampen the objects to be washed placed within the basket 10 which are exposed or which are found on the upper part. This is followed by the electric control 40 counting a set amount of waiting time; once this time has lapsed, the sequence is repeated sending a new pulse for a similar amount of time to the driver 71 of the spray pump 15 , repeating this process for a determined amount of time which varies between 2 to 5 minutes.
[0046] An alternative embodiment of the present spraying sequence 66 comprises the use of a directional valve 36 which is connected to the drain pump's 36 exit by means of a duct or a hose (not shown). One of the exits of said directional valve is connected to the spray hose 17 and the remaining one to the drain hose 16 , taking into account that within the tub 11 there is a certain determined volume of washing mixture which is greater than or equal to the minimum level or water level II, the electric control 40 sends a pulse for a determined amount of time which can vary between 0.5 seconds to 2 seconds, to the driver 75 of the drain pump 35 , and at the same time sends a pulse for the same amount of time to the driver 76 of the directional valve 36 so that it may send water towards the spray deflector 18 by means of the spray hose 17 so that it may dampen the objects placed in the basket 10 which are exposed or that are placed on the upper part. This is followed by the electric control 40 counting a determined amount of waiting time. This time having lapsed, the sequence is repeated sending a new pulse for a similar amount of time to the drain pump's 35 driver 75 and in its case (depending on the type of valve to be used), a pulse is sent in the same instant for the same amount of time to the directional valve's 36 driver 76 so that it may send water to the spray deflector 18 by means of the spray hose 17 , repeating this process for a set amount of time which varies between 2 and 5 minutes.
[0047] This sequence can be activated by the electric control 40 in intermittent form while the filling valves 45 are energized, or during the load sensing sequences 65 , normal agitation sequences 60 , or reshuffling of load sequences 61 , in the high load agitating sequences 62 or in the high density sequences 67 .
Dehydrating 69
[0048] The dehydrating stage helps to extract the washing mixture. This sequence takes place by making the basket 10 turn, so that by centrifuge force, the washing mixture is pushed to the wall with holes in the basket 10 to be extracted by means of said holes towards the tub 11 , where the extracted washing mixture is pumped towards the exterior by means of the drain pump 35 which on its exit is connected to a drain hose 16 . Then the electric control 40 sends a pulse for a set amount of time varying between 2 and 8 minutes to driver 75 of the drain pump 35 , at the same time it also sends a signal to the driver 73 of the clutch 28 so that it may change from agitation mode to dehydrating mode. In an alternative embodiment to the present invention, the clutch can be a floating clutch which with the presence or absence of washing mixture can either clutch or un-clutch the shafts 25 and 26 , being evident that said floating clutch will not use an actuator and thus the electric control will not be able to send a signal to either activate it or de-activate it. Thus the clutch being in dehydrating form, the electric control also sends a pulse for a set amount of time to the driver 72 so that it may energize the motor 21 , thus turning the basket 10 in unison with the agitator or propeller 13 . Said pulse sent be the electric control 40 can vary depending on the type of centrifuge which is needed. In this way, in a an alternative embodiment, a set of pulses with varying widths can be sent with the goal of accelerating and decelerating the basket 10 to extract less water upon deceleration of the basket giving the drain pump 35 enough time to extract the washing mixture accumulated in the tub's bottom 11 , and additionally avoiding accumulation of foam problems between the tub 11 and the basket 10 , main cause of the phenomenon known as “sudsing”.
[0049] In an alternative embodiment of the present invention, the motor 24 can be energized intermittently allowing for the deceleration of the basket 12 giving the pump enough time to extract the washing mixture accumulated in the tub's bottom, with the purpose of avoiding “sudsing”, which occurs when water accumulation in the tub's bottom makes contact with the washing mixture while the basket turns, where friction creates high superficial tension which the washing mixture has, coupled to the velocity with which said washing mixture is projected unto the tub's 11 circular wall, thus generating a high concentration of foam between the ring space of the basket's and the tub's, which can even cause the basket 12 to stop even with the motor 24 energized. It can also have any other method of prevention or “sudsing” management available in the industry.
Rinsing 70
[0050] In the rinsing stage the detergent residues, chemical additives or dissolved chemicals remaining on the objects to be washed are removed, this can take place in different ways. Traditionally the tub 11 is filled with fresh water to a set level, followed by agitation by means of the agitator or propeller 13 for a set amount of time. This is followed by the extraction of washing mixture and the centrifuge of the objects to be washed in the basket 10 . Alternative embodiments can be found in previous art, in such a way that the procedure described in the art be a rinsing which requires a significantly lesser amount of water than the one used by traditional rinsing methods.
[0051] Having thoroughly described the present invention, it is found to have a high degree of inventive activity, its industrial application being undeniable, assuring at the same time that someone with knowledge in the field can glimpse at alternative embodiments which can be included within the reach and spirit of the following claims. | The present invention relates to the field of washers, particularly that of top loading household washers which has a cabinet which supports a tub which houses a basket which rotates concentrically within it, the basket being driven by a motor which is mechanically coupled to an agitator and to said basket, a clutch which allows the coupling and uncoupling between basket and agitator, an electric control which controls the switches by means of drivers, a level sensor or pressure switch and a rotor's position sensor within the motor (preferably a Hall sensor), a spraying system, characterized by a washing method which comprises the following sequences; check on the water level, initiate a load pre-sensing sequence, to later initiate a reshuffling of load sequence, act followed by initiating a load sensing sequence, which determines the water level required to admit, once said water level is reached, a normal agitation sequence is begun, which if during its course a clog of objects to be washed is detected or an unusual high density of these is detected or in its case a maximum load agitation sequence; once the normal agitation sequence concludes, it is followed by a load reshuffling sequence in order to continue with the dehydrating and later rinsing. | 3 |
This application is a continuation of application Ser. No. 08/481,147 filed Jun. 7, 1995, abandoned which is a division of application Ser. No. 07/853,062, filed Mar. 17, 1992.
FIELD OF THE INVENTION
This invention relates to data processing and storage systems and in particular to methods and means for specifying the syntax of a hierarchical language for use in data transmissions of such systems.
BACKGROUND OF THE INVENTION
Data processing, for instance distributed processing, requires a connection protocol that defines specific flows, and interactions. These flows and interactions convey the intent and results of distributed processing requests. The protocol is necessary for semantic connectivity between applications and processors in a distributed environment. The protocol must define the responsibilities between the participants and specify when flows should occur and their contents. Distributed applications allow operations to be processed over a network of cooperating processors.
Clients and servers send information between each other using that set of protocols. These protocols define the order in which messages can be sent and received, the data that accompanies the messages, remote processor connection flows, and the means for converting data that is received from foreign environments.
The client provides the connection between the application and the servers via protocols. It supports the application end of the connection by: (1) Initiating a remote connection (2) Translating requests from the application into the standardized format, otherwise known as generating, (3) Translating replies from standardized formats into the application format, otherwise known as parsing, (4) Disconnecting the link from the remote processor when the application terminates or when it switches processors.
The server responds to requests received from the client. It supports the server end of the connection by: (1) Accepting a connection (2) Receiving input requests and data and converting them to its own internal format (parsing), (3) Constructing (generating) and sending standardized reply messages and data.
In particular, a distributed data processing architecture can use the Distributed Data Management Architecture (DDM) for providing the standardized format of the messages. DDM provides the conceptual framework for constructing common interfaces for command and reply interchange between a client and a server. Most DDM commands have internal statement counterparts.
DEFINITIONS
The following definitions are provided to assist in understanding the invention described below. Additional information may be found in the manual, "IBM Distributed Data Management Architecture Level 3: Reference, SC21-9526".
DSS (Data Stream Structure): DDM can be viewed as a multi-layer architecture for communicating data management requests between servers located on different data processing systems. All information is exchanged in the form of objects mapped onto a data stream appropriate to communication facilities being used by DDM. A data stream structure is a set of bytes which contains, among others, information about whether the enclosed structure is a request, reply, or data (an object structure); whether the structure is chained to other structures; etc. There are three general types of DDM data stream structures: "request structures" (RQSDSS) which are used for all requests to a target system for processing; "reply structures" (RPYDSS) which are used for all replies from a target system to a source system regarding the conditions detected during the processing of the request; and "object structures" (OBJDSS) which are used for all objects sent between systems.
Mnemonic: specifies a short form of the full name of a DDM object.
Class: describes a set of objects that have a common structure and respond to the same commands.
Codepoint: A codepoint (code point) specifies the data representation of a dictionary class. Codepoints are hexadecimal synonyms for the named terms of the DDM architecture. Codepoints are used to reduce the number of bytes required to identify the class of an object in memory and in data streams.
Command: Commands are messages sent to a server to request the execution of a function by that server. For example, the command "Get -- Record" can be sent to a file system. Each DDM command normally returns (results in the sending of) one or more reply messages or data objects.
DDM commands can be described under four headings:
1. Description: The description part usually includes, a Command Name, or the mnemonic name of the command, such as "OPNQRY"; and an Expanded Name, such as "Open Query", that is a description of the command function.
2. Parameters: The parameters or instance variables describe the objects that can (or must be) sent as parameters of the command. The parameters can be sent in any order because they are identified by their class codepoints. The parameters are generally associated with a set of attributes (characteristics):
(a) required, optional, or ignorable. A Required attribute specifies that support or use of a parameter is required: when a parameter is specified as being required in a parameter list for a command, the parameter must be sent for that command. All receivers supporting the command must recognize and process the parameter as defined. When specified in the parameter list of a reply message, the parameter must be sent for that reply message. All receivers must accept the parameter. An Optional attribute specifies that support or use of a parameter is optional. When a parameter is specified as being optional in a parameter list for a command, the parameter can optionally be sent for that command. All receivers supporting the command must recognize and process the parameter as defined and use the default value if it is not sent. When specified in the parameter list of a reply message, the parameter can optionally be sent for that reply message. All receivers must accept the parameter. An Ignorable attribute specifies that a parameter can be ignored by the receiver of a command if the receiver does not provide the support requested. The parameter can be sent optionally by all senders. The parameter must be recognized by all receivers. The receiver is not required to support the architected default value and does not have to validate the specified value;
(b) Repeatable or Not Repeatable: A Repeatable attribute specifies that a parameter can be repeated in the value of the object variable being described. There are no requirements that the elements of the list be unique or that the elements of the list be in any order;
(c) Length characteristic: This describes the length requirements or restrictions of the corresponding data transmission.
3. Command Data: the list of all the possible classes of data objects (for example, records) that can be associated with the command. Each data object is generally associated with a set of attributes (characteristics), as are the parameters.
4. Reply Data: The reply data section lists all possible classes of data objects that can be returned for the command. The list may contain notes about selecting the data objects to return. The reply data objects that are normally returned for the command. When exception conditions occur, the reply data objects may not be returned, instead reply messages may return a description of the exception conditions.
All DDM commands may be enclosed in a RQSDSS before transmission:
______________________________________RQSDSS(command(command parameters))All DDM command data objects and reply data objects maybe enclosed in an OBJDSS structure for transmission.OBJDSS(command-data-object(object parameters))OBJDSS(reply-data-object(object parameters))All DDM command replies may be enclosed in a RPYDSSstructure for transmission:RPYDSS(command-reply(reply parameters))______________________________________
Parsing: the process of verifying syntactic correctness of a DDM string (DDM stream), and of translating it into a recognizable internal format.
Generation: the process of creating a valid DDM string from an internal format.
Tree: A tree structure is either: (a) an empty structure, or (b) a node with a number of subtrees which are acyclic tree structures. A node y which is directly below node x is called a direct descendent of x; if x is at level i and y is at level i+1 the x is the parent of y and y is the child of x. Also, x is said to be an ancestor of y. The root of the tree is the only node in the tree with no parent. If a node has no descendents it is called a terminal node or a leaf. A node which is not a terminal node nor a root node is an internal node.
DDM Architecture Dictionary: The architecture dictionary describes a set of named descriptions of objects. The primary objects listed in the dictionary are broken down into the classes "CLASS" and "HELP". Each of these objects has an external name and an external codepoint that can be used to locate it. These are complex objects (nested collections of many sub-objects). The entries in a dictionary are of varying length and each contains a single complete object. For scalar objects, all of the data of the object immediately follows the length and class codepoint of the object. For collection objects, the data following the length and class codepoint of the collection consists of four byte binary numbers specifying the entry number in the dictionary at which the collection is stored. The DDM Architecture Dictionary is also referred to as the DDM Architecture document.
DDM Architecture: The DDM architecture is fully described by the DDM Architecture Dictionary.
Forest: A grouping of trees.
Parameter: There are three kinds of DDM objects, as shown in FIG. 1.
First there are simple scalars which contain only a single instance of one of the DDM data classes, such as a single number or a single character string. DDM attributes, such as length, alignment and scale are simple scalars.
Then, there are mapped scalars which contain a sequence of instances of the DDM data classes that are mapped onto a byte stream by an external descriptor that specifies their class identifier and other attributes.
Finally, there are collections which contain a sequence of scalar and collection objects. DDM commands, reply messages, and attribute lists are all examples of collection objects.
All objects (including parameters) are transmitted as a contiguous string of bytes with the following format:
(a) a two byte binary length. The length field of an object always includes the length of the length field and the length of the codepoint field, as well as the length of the object's data value;
(b) a two byte binary value that specifies the codepoint of the class that describes the object. All objects are instances of the "CLASS" object that specifies the variables of the object, specifies the commands to which the object can respond, and provides the programming to respond to messages;
(c) an object's data area consists of the data value of primitive classes of objects, such as numbers and character strings, or the element objects of a collection. A parameter can be either a scalar or a collection.
Since the class of a DDM object describes its parameters, it thereby defines the interchange data stream form, as shown in FIG. 2. This makes it possible to transmit a command consisting of multiple scalar parameters from one manager to another.
Definition: A definition as used in reference to data processing structures and operations described herein is the association of a name with an attribute list. Definitions are used to specify the characteristics of variables, values and other aspects of objects.
Database Management System (DBMS): A software system that has a catalog describing the data it manages. It controls the access to data stored within it. The DBMS also has transaction management and data recovery facilities to protect data integrity.
SQL (Structured Query Language): A language used in database management systems to access data in the database.
Depth First Search: is a means of systematically visiting nodes in a tree. The order is as follows: (1) Visit the root node; (2) Visit the children of the root node; (3) To visit a child, chose its children and visit them in turn. In general, other alternatives at the same level or below are ignored as long as the current node that is being visited is not a terminal node. One way to implement depth-first search is depicted in FIG. 3.
The corresponding pseudo-code is:
1. Form a one element queue consisting of the root node.
2. Until the queue is empty, remove the first element from the queue and add the first element's children, if any, to the front of the queue.
Other types of searches are possible, such as breadth-first search, which expands the nodes in order of their proximity to the start node, measured by the number of arcs between them.
Application Requester(AR): the source of a request to a remote relational database management system (DBMS). The AR is considered a client.
Application Server(AS): the target of a request from an AR. The DBMS at the AS site provides the data. The AS is considered a server.
Description of the IBM Distributed Data Management (DDM) Language
The Distributed Data Management (DDM) Architecture (as described in the IBM publication, "IBM Distributed Data Management Architecture Level 3: Reference, SC21-9526"describes a standardized language for Distributed Applications. This language is used by the data management components of existing systems to request data services from one another. It manipulates data interchange amongst different kinds of currently existing systems; efficient data interchange amongst systems of the same kind; common data management facilities for new systems; and evolution of new forms of data management. DDM provides the abstract models necessary for bridging the gap between disparate real operating system implementations. Some of the services addressed by the DDM distributed database models are to
(a) establish a connection with a remote database;
(b) create application specific access methods (packages) in the database or dropping them from the database. These packages include the definitions of application variables used for input and output of SQL statements defined by the Application Requester;
(c) retrieve descriptions of answer set data;
(d) execute SQL statements bound in a database package;
(e) dynamically prepare and execute SQL statements in the database;
(f) maintain consistent unit of work boundaries between the application requester and the database;
(g) terminate the connection with the database.
Specification of DDM Objects
The DDM Architecture is defined by a "dictionary" of terms that describe the concepts, structures, and protocols of DDM. DDM entities are called objects. They are also synonymously called terms. See FIGS. 4a and 4b for a sample DDM Object. The object drawn is EXCSATRD (Exchange Server Attributes Reply Data). In crder to obtain more information about the object EXCSATRD, one should look at the objects that form EXCSATRD. For example, the objects EXTNAM, MGRLVLLS, SRVCLSNM, SRVNAM and SRVRLSLV, which constitute the parameters of EXCSATRD are themselves DDM objects and can be found elsewhere in the architecture (architecture dictionary) in alphabetical order. Every object has a help variable. This variable is for supplemental information and explains the purpose and the semantics of the object. Another example of a DDM Command as documented in the DDM architecture reference, above is depicted in FIGS. 5a, and 5b.
Like object-oriented languages, DDM has three characteristics that make it object-oriented. These are encapsulation, inheritance, and polymorphism.
Encapsulation is a technique for minimizing interdependencies amongst separately written objects by defining strict external interfaces. DDM uses this concept to define each object class (an instance of which is an object) that is part of the architecture. Most of the DDM object classes have the following attributes: inscmd (instance commands), clscmd (class commands), insvar (instance variables), clsvar (class instance variables). In addition, there are other attributes, namely length and class.
Length indicates length or size of the object. There are two length attributes associated with most objects: one is the abstract length referring to the fact that if the entire object class were to be transmitted, including help text, it would be as long as the value specified with the attribute. This is always "★", where "★" represents a indefinite length due to its abstract nature. The second length attribute is a part of the instance variable list. It specifies the length of the object when it is transmitted as part of the protocol. The length of some objects is clear (fixed) at the time of definition. Most objects however, have variable lengths which are determined depending on their use. Thus, these objects have their lengths available only at the time of transmission of the objects.
Class indicates the class name or codepoint. Each object class has a name which briefly describes its type. Each object class also has a codepoint which is an alternate and more efficient (for transmission) way of naming it. This attribute is specified twice for every DDM object class, first as a brief description and then, as part,of the instance variable list (as a hexadecimal number). There are some DDM objects which are not self-describing, when they are transmitted. That is, when these objects are transmitted they are recognized by the receiver from the context; the length and the codepoint which are essential for the recognition of the object by the receiver are not transmitted even though these attributes are defined for these objects by DDM. The second characteristic,
Inheritance is a technique that allows new, more specialized classes to be built from the existing classes. DDM uses the inheritance structure to encourage the reusability of the definition (and eventually of the code, if the implementation is object-oriented). The class COMMAND for example, is the superclass of all commands. From the superclass, the subclass inherits its structure. The third characteristic,
Polymorphism is a technique that allows the same command to be understood by different objects, which respond differently.
In this disclosure, the following will be used:
N: the number of terms in the dictionary (number of trees),
m: the number of total nodes in the expansion of a DDM command or reply message (number of nodes in a tree;
k: number of top level nodes, approximately N/10 in the specific application described herein;
j: average number of children per node.
Other Methods
This section describes other methods of hierarchical language storage and retrieval methodologies, including Loosely Coupled Files (LCF) and Root Storage Method (RSM).
Loosely Coupled Files (LCF)
Given that the DDM model isolates dictionaries from processing, LCF design represents the DDM dictionaries by a collection of static data structures, which may be generated by macros. Each DDM Dictionary is assembled and link-edited into separate load modules. Isolation of DDM objects requires as search arguments, (a) the object name (character string) and (b) the dictionary identification. The dictionaries closely resemble the structure of the DDM documentation i.e., comprising a network of nodes. Thus, if one is familiar with the DDM documentation, one may correlate DDM concepts (scalars, collections, codepoints) to the LCF DDM Dictionaries.
LCF Retrieval Methodology:
Since but a single definition of each DDM object exists, the requirement to generate the object or to recognize its existence is dependent upon that single definition. Thus, LCF creates generation and parsing methods which are driven entirely by the DDM dictionaries. Any DDM object to be generated first isolates the object definition within the appropriate dictionary. Then, it "pushes" the length and codepoint attributes onto a stack if the object is a collection and proceeds recursively through all the instance variables of the collection, halting when a scalar (leaf or terminal node) is encountered. When a scalar (terminal node) is reached, a generator routine is invoked, which "pushes" the scalar length, codepoint as well as the scalar value onto the stack. The length is returned to the invoker at the higher level. In this fashion, when all instance variables of a collection have been processed, the length of the collection is the sum of the lengths returned from the individual invocations. The example below depicts the LCF pseudo-code for building the definition at run-time. Note that recursion is used. Another way is depicted in FIG. 6 without recursion (i.e., recursion is simulated).
EXAMPLE
______________________________________Newdef LCF.sub.-- Construct (IN Codepoint)(*LCF Method for constructing Definition*)Search for the file identified by the CodepointScan for all its parameters (or instance variables) if anyIf There Are Some Then Do;Scan file for instance variablesDo for all the Instance VariablesDefinition = Definition +LCF.sub.-- Construct(Codepoint)End Do;End If;End LCF.sub.-- Construct;______________________________________
To illustrate the LCF flow and provide some insight with regard to the impact of Dictionary access and recursion on path length consider the example illustrated in FIG. 7 which depicts the definition tree to be built. LCF maintains 13 files for this tree. To illustrate the LCF flow and provide some insight with regard to the impact of Dictionary access and recursion on path length consider the example as depicted in FIG. 8.
Hence, LCF retrieves each file, sequentially searches for parameters in each file (the search argument is a variable length character string, or DDM Mnemonic, such as RDBNAM in the example above), and then for each parameter found, gets the file and extracts its parameters. This is a recursive method. This recursive step is done at run time, each time one wants to generate or parse a DDM stream. This means that the methods to construct a DDM Dictionary definition is an exhaustive search that goes through the entire file: Hence, in order to build the definition, LCF requires m retrievals and with each retrieval there is a sequential search to locate the parameters.
LCF Storage Methodology:
LCF stores each DDM definition in shown in the format shown in FIGS. 5a and 5b. This means that each term is stored in a separate file with information that is not needed by the parsing and generation processes. Also each of its instance variables are stored in the same fashion, etc.
The storage requirements for LCF are approximately 1000+100m bytes per term in the dictionary, i.e., assuming 1000 bytes head and tail overhead plus 100 bytes per internal node. Hence, the storage requirements for the entire dictionary are approximately: (1000+100m) N.
Root Storage Method
The Root Storage Method (RSM) approximates or simulates the recursion aspects of DDM object definition construction by an appropriate implementation technique (nested CASE statements, CASE within CASE within CASE). Given this direction, the objects defined within the DDM dictionaries can be entirely eliminated or restricted to objects of a given type. RSM restructures the DDM Dictionaries by first eliminating the dictionary identifier as an element in the search argument, and hence all dictionaries are merged together. Then, the dictionary search arguments are changed from character strings to codepoints. The character strings are still maintained within the dictionary. Finally, objects defined within the dictionaries are restricted to root nodes only. Thus, only DDM commands, command data, reply messages and reply data are defined. However, the constituent instance variables of any given DSS (or parameters), collection or scalar are not defined.
RSM Retrieval Methodology
Once the object has been identified to satisfy a request, then for each root level object, a unique root level object generator exists, which will generate one complete object. The object generator non-recursively constructs the instance variables (collections and scalars) which constitute the object. Consequently, the Generator must simulate the recursion inherent in the generation of all instance variables comprising that object. FIG. 9 depicts the CASE within CASE method. FIG. 10 depicts the flowchart of RSM object construction. With this approach, the DDM dictionaries are partitioned such that objects are defined within static data structures and the constituent instance variables are hardcoded. Note that in this method, the definitions of the various parameters are hardcoded multiple times, and that this method is not extendible to all possible variations of DDM. For example, it has the limitation in the number of levels of nesting that CASE statements are allowed.
To construct the definition for ACCRDBRM (as depicted in FIG. 7), RSM undertakes the steps depicted in FIG. 11.
To construct a definition, one must execute one retrieval with cost proportional to Log N to the base 2, and m CASE statements. Thus, RSM retrieves the root term definition. Thereafter, the parameters' expansions are hard-coded into the procedure. This method approximates the recursion aspects of DDM Object Generation by an implementation technique (e.g., CASE within CASE . . . etc.). Due to limitations in programming languages, there are only so many levels of nesting of case statements that are possible, hence making the method not expandable. This appears to be a hard limitation. If DDM expands to have more levels, the RSM will exhaust its usefulness. If DDM strings reach a depth exceeding the nesting limit, then redesigning of the code will have to be done. In addition, this method is not well suited to parsing, because DDM is not static. When parsing DDM Strings the parameters at each level of DDM term in the tree can appear in any order. The CASE within a CASE . . . does not provide all possible combinations of parameter ordering. Also, for each occurrence of the parameter in the dictionary, the semantic procedure associated with it is duplicated. The programs are hardcoded, and therefore difficult to maintain. Due to the increased size, the programs are more complex. In order to maintain the program, recompilation is performed each time. Hence, in order to obtain the definition of the DDM term, there is one retrieval necessary and one sequential search in the top level file. Then, a series of embedded CASE statements provide the rest of the DDM definition.
RSM Storage Methodology
RSM stores only the root or "top level" definitions. The constituent instance variables of the parameters are not defined. This means that only the top level codepoint definitions are stored as data. All the parameters derived through the root are hardcoded in the program. This results in the loss of information, including some of the necessary information required to parse and generate a DDM string. That is, all the information about the structure of the parameters is not available as data. If there are changes in the dictionary, this may result in consistency problems. While LCF stored all the information for all the codepoints, this method only stores the structural information for the top level codepoints. The storage requirements for RSM are approximately 1000+100m per top level term assuming 1000 bytes for head and tail overhead plus 100 bytes per internal node. Hence, there are about (1000+100m)k for the entire dictionary. The rest of the information for the structure of the parameters is hardcoded in the program as depicted in FIG. 9. Assuming there are N/10 top level objects, then the cost of storage is (1000+100m) N/10 bytes.
Drawbacks of the LCF and RSM Methods
LCF maintains a set of files without constructing the definition. This means that each time a definition of an object is required, LCF has to reconstruct it using the methods described above. There is no added value to reconstructing the definition each time it is required since the same definition will be required over and over again. In addition, LCF does not keep a very compact form of each of the definitions of each of the parameters; it remembers information that is not needed, i.e., information that is not essential for parsing and generating. The invention herein overcomes these drawbacks by expanding the definition of a DDM command inside the data structure, and therefore not requiring its reconstruction each time it is accessed and by defining a short form of the data to describe the essence of the definition in a few bytes.
RSM only stores the top level node definition of the tree. The rest of the definition is hardcoded in the program. While this saves on space compared to the LCF method, RSM does not record the information of the root node in a compact fashion. RSM maintenance may be difficult due to hard coding of each parameter and duplication of code for each instance of the parameter in the dictionary. RSM is also subject to the limitations of programming languages such as the level of nesting of CASE statements. The invention herein overcomes these problems.
SUMMARY OF THE INVENTION
Inconveniences of other methods discussed above and elsewhere herein are remedied by the means and method provided by the instant invention which is described hereafter.
In accordance with one aspect of the invention a data transmission dictionary is provided, which is adapted for use by a computer system for encoding, storing, or retrieving hierarchically related data transmission information. The dictionary is comprised of a group of one or more computer searchable definition trees relating to transmission information of the computer system. The trees are derived from a first definition group which includes characteristics of commands, replies or data usable by the computer system. The characteristics include structure and value properties and restrictions, if any, applying to the commands, replies or data. Each tree represents, respectively, a definition of the command, reply or data to which it relates. Each tree includes a root node identified by name, such as a codepoint. The root node includes information describing the type of definition tree concerned (i.e., whether it relates to a command, reply or data), and may include one or more internal or terminal descendant nodes, which nodes represent components of the definition represented by the tree. The descendent nodes include level information describing the level of the node within its tree. The nodes may include attribute information, and may include value requirements relating to transmission information represented by the nodes.
The root node of each definition in the dictionary may include information relating to length restrictions of transmission information represented by its definition tree.
The attribute information may include a requirement as to whether data transmission information represented by a node is required, optional or ignorable.
The attribute information also may include information on length, repeatability or non-repeatability of data transmission information represented by the node.
Advantageously, the root node of each of the definition trees may be made the sole accessible entry for the tree.
As their size tends to be compact the definition trees may be stored in main memory of the computer system using them for use by parsing or generating programming to process data transmission for the computer system.
Advantageously the definition trees are stored in a compact linear form preferably expressed in a depth first search form.
In accordance with another aspect of the invention there is provided a method of creating the data transmission dictionary, above, by deriving a group of one or more computer searchable definition trees from a first definition group of nodes defining portions of commands replies or data usable by a computer system, compacting each of the nodes by retaining only information necessary for the processing of data transmission streams according to the definition trees; assembling each definition tree by sequencing the compacted nodes in a linear form, starting with the root node of each of the definition trees, by placing information included in each compacted node in a resulting implemented dictionary; and by assembling each child node of said definition tree in turn. The process of assembling each child node involves placing information included in the child node in the resulting implemented dictionary and assembling each of the child's child nodes in turn. The process of assembling a terminal node involves placing information included in the terminal node in the resulting implemented dictionary.
In accordance with still another aspect of the invention means is provided for constructing the data transmission dictionary described above which comprise an extractor for deriving a group of one or more computer searchable definition trees from a first definition group of nodes defining portions of commands replies or data usable by a computer system. A compactor is provided for compacting each of the nodes while retaining only information necessary for the processing of data transmission streams according to the definition trees. An assembler is provided for assembling each definition tree starting with the root node for each tree. The assembler can place information included in each compacted root node in the resulting implemented dictionary and assemble each of the compacted node's child nodes, if any, in turn. The assembler is adapted to place information included in each child node in the resulting implemented dictionary and to assemble each of said child's child nodes, if any, in turn.
In accordance with a further aspect of the invention the dictionary described above is incorporated into a computer system for use by it for encoding, storing, or retrieving hierarchically related data transmission information for use by said computer system internally or in communication with another computer system.
In accordance with another aspect of the invention there is provided a method of encoding and decoding a data transmission of one or more computer systems using the dictionary described above using the following steps:
separating the data transmission into command, reply, or data parts corresponding to individual definitions in the dictionary, and ensuring that the parts conform to required specifications of the data transmission protocol used by the system;
for each of the parts, retrieving a corresponding definition tree from the dictionary, and
stepping through the data transmission ensuring that required information is present and that relevant rules are obeyed for the tree structure for each of said nodes encountered in the data transmission; and also ensuring that structural and value rules relating to the nodes, as described in the definition corresponding to the node are adhered to.
Advantageously, in the above method when used for encoding the data transmission the dictionary definitions serve as a roadmap for the translation of internal data structures of the computer system into a data transmission which conforms to requirements of the definitions.
Advantageously as well in the aforementioned method when used for decoding a data transmission the dictionary definitions serve as a roadmap for the verification of the data transmission according to the definition requirements and the translation into internal data structures of the computer system.
In accordance with another aspect of the invention there is provided a distributed computer system comprising a source system and destination system. The source system includes an application requestor, a parser and a generator supporting the application requestor. The destination system includes a server and a parser and generator supporting the server. The parsers and generators have access to one or more dictionaries constructed in accordance with the dictionary described above for the purpose of processing data transmissions between the source and destination systems.
The distributed computer system described above may contain the destination and source systems within one or a local computer system.
In accordance with yet another aspect of the invention a data processing dictionary is provided, which is adapted for use by a computer system for encoding, storing, or retrieving hierarchically related data processing information. The dictionary is comprised of a group of one or more computer searchable definition trees relating to data processing information of the computer system. The trees are derived from a first definition group which includes characteristics of commands, replies or data usable by the computer system. The characteristics include structure and value properties and restrictions, if any, applying to the commands, replies or data. Each tree represents, respectively, a definition of a the command, reply or data to which it relates. Each tree includes a root node identified by name. The root node includes information describing the type of definition tree concerned (i.e., whether it relates to a command, reply or data), and may include one or more internal or terminal descendant nodes, which nodes represent components of the definition represented by the tree. The descendent nodes include level information describing the level of the node within its tree. The nodes may include attribute information, and may include value requirements relating to data processing information represented by the nodes.
It may prove advantageous for some of the nodes of the tree to be linked to data stored by the data processing system for representing or accessing the data stored.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts DDM Objects.
FIG. 2 depicts a DDM Object Interchange Format.
FIG. 3 depicts a flowchart illustrating depth first searching.
FIGS. 4a,b illustrate an example DDM Object: Root Node as defined in the architecture.
FIGS. 5a,b illustrate an example of the Root Node OPNQRY.
FIG. 6 comprises a diagram representing a method of constructing the definition for loosely coupled files.
FIG. 7 illustrates a tree for the Command portion of ACCRDBRM.
FIG. 8 depicts an example of retrieving a definition for the LCF method.
FIG. 9 depicts a CASE method as used in RSM.
FIG. 10 comprises a diagram representing the construction of a DDM definition by the root storage method.
FIG. 11 depicts an example of retrieving a definition for the RSM method.
FIG. 12 depicts an ADDG Flowchart.
FIG. 13 depicts a flowchart for step 1 of ADDG; generate DDMTXT.
FIG. 14 depicts a flowchart for step 2 of ADDG; create DDM definitions.
FIG. 15 depicts a flowchart for step 3 of ADDG; assemble DDM definitions.
FIG. 16 depicts ADDG tool pseudocode.
FIGS. 17a-l depict an implemented DDM dictionary and retrieval method in accordance with the instant invention.
FIG. 18 comprises a representation of a DDM Command in the form of a tree.
FIG. 19 illustrates the DDM Dictionary Definition Syntax.
FIG. 20 depicts parsers and generators in a Distributed System.
FIG. 21 illustrates a tree for the Command portion of OPNQRY.
FIG. 22 illustrates a tree for the Command Data portion of OPNQRY.
FIG. 23 illustrates a tree for the Reply Data portion of OPNQRY.
FIG. 24 depicts the method of parsing and generation employed by the instant invention.
DETAILED DESCRIPTION OF THE INVENTION
In the invention described herein below the definitions of DDM commands, replies, and data are stored in command, reply, and data trees, respectively.
This invention which will be termed the DDM Dictionary Structure Optimizer (including method and means) (DDSO) compacts the definition of nodes of the DDM command and reply data trees by retaining only the information necessary for parsing and generation of the DDM data streams. DDSO also assembles the definition of a DDM command, reply, or data by sequencing the compacted nodes in the corresponding tree in a depth first search manner. Definitions are created by first scanning the DDM Architecture document (which may be on line advantageously) and then by extracting the necessary information. Then, each of the definitions is assembled. In order to explain DDSO, it is first described how to create the DDM Dictionary structure of the invention from the DDM architecture document, then what the storage and retrieval methodologies are, and the formal specification of the definition syntax. Finally, we discuss the advantages and disadvantages of DDSO are discussed.
Creating the DDM Dictionary Data Structure
The DDM Dictionary Data Structure is a compact form of definitions derived from selections of the dictionary defined by the DDM architecture document. Each definition is expressed as a tree (having one or more nodes) in a linear form, and preferably expresses it in depth first search form, with each of the nodes defined in a compact form. In general, the steps are the following:
Step 0: (Extraction Stage)
Get all the codepoints (identifiers of the nodes) for the trees required in the forest. The DDM architecture provides a network of nodes that are pointing to each other. This stage extracts the nodes needed for the trees of the application. Only the root nodes are given to the Extraction Stage. This step calculates which nodes are needed for the definitions.
Step 1: (Compaction Stage)
Scan all the DDM files created in step 0 for essential information, i.e., the top level codepoint for each node and all node parameters. Retain the information in DDSO form for the parameter. The specifics of the DDSO form are described below. An example of DDSO form is: "RN1: 2401,★255", which indicates attributes (RN), level in the tree (1), unique identifier (2401) and length attribute (★255).
Step 2: (Assembly Stage)
This step assembles (expands) each of the parameters. This means that if a parameter itself has parameters (i.e., it is a parent) then the children are added in a depth first search manner, and they are given one level higher than that of the parent.
ADDG (Automated DDM Dictionary Generator) is a convenient tool which can be used to create one or more DDM Dictionary data structures (dictionaries) from the DDM architecture document. ADDG has three steps, as depicted in FIG. 12:
1. Generate DDMTXT: This exec steps through the DDM architecture document extracting the information required by the user. This includes the root nodes specified by the user, as well as all the nodes required in the expansion of the root nodes. Each of these nodes is extracted into a file with filename equal to the DDM mnemonic term and a file type of DDMTXT. Other files are generated, such as DDM FLVL which provides a list of all DDM terms which are going to be expanded; EXPCDPT FILE which provides a list of all valid part specifications (a part specification specifies whether the DDM object is a command, reply, or data object) and their corresponding DDM codepoints and DDM HEX which provides a list of all DDM mnemonics with corresponding codepoints. The generate -- DDMTXT high level flowchart is depicted in FIG. 13.
2. Create DDM Definitions:
The Generate -- DDMTXT exec must be run before the Create -- DDM -- Definitions exec. Create -- DDM -- Definitions creates the DDM -- DEF FILE which contains a DDM definition for each DDM Term. It follows the specific rules that were setup in the DDSO form for the dictionary. Create -- DDM -- Definitions is depicted in FIG. 14.
3. Assemble DDM Definitions
The Generate -- DDMTXT and Create -- DDM -- Definitions execs must have been executed before this exec is run. This exec assembles all top level DDM terms by assembling parts of several DDM definitions. It also contains the source language specific statements in order to store each definition. The definitions are stored in a file. Pseudocode for the Assemble -- DDM -- Definitions is depicted in FIG. 15.
The pseudocode for the ADDG tool is shown in FIG. 16.
There are therefore two main operations involved in constructing the definition and these are compaction and assembly. Compaction involves storing each parameter in the compacted form, while assembly is an expansion process that reassembles a complete definition of a root node in depth first search format. It is possible to compact the definitions of each parameter without performing the assembly. Resulting storage savings over LCF will occur. However, the performance overhead of LCF to create the definition will have to be incurred, since the definition will have to be created at run-time as opposed to creating the definition before runtime, as is done in the instant invention. It is also possible to assemble the definition without compacting it. Due to the duplication of certain internal nodes, and large storage requirements for each node, this alternative may not prove attractive. However, if compaction and assembly are both done then maximum benefits may be obtained from the instant invention.
Storage Methodology
DDSO stores the DDM definition files in the format shown by the example depicted in FIGS. 17a-l. A DDM definition is a linear expression of a tree, assembled in depth first search manner, and contains information required, namely: information required for the root node and information stored for non-root nodes. The root node requires 6 bytes for its definition and each non root node requires 11 bytes. If there are m nodes in the tree then the tree requires 11m+6 bytes. Hence, for N trees in a dictionary, 11mN+6N bytes are required. In addition, a small search table requires 6 bytes per tree, hence 6N bytes. Therefore the total implementation requires 11mN+12N bytes.
Note that in the example, the constants 11 and 6, i.e., the number of bytes per internal and root nodes respectively are slightly higher. Certain additional characters ("/"'s) and punctuation (",") were added to improve human readability.
For the example application, approximately 5088 bytes of data are required for the dictionary itself and a small lookup table of about 510 bytes for the purposes of searching. Since the definition is already constructed, the cost of retrieval reduces to the cost of a search through the lookup table, e.g., the cost using binary searching.
1. Information Stored for Root Node:
The following attribute information is stored for the root node:
(a) Carrier Type: i.e., whether it is a request, reply, or data object. In DDM there is one general format for the request data stream structure. The request envelope (RQSDSS) fields must be specified in a certain order because they are not self-defining structures. Only one command can be carried by a RQSDSS. Similarly, in DDM there is one general format for the reply data stream structure. All fields must be specified in the order required because the reply envelope (RPYDSS) is not a self-defining structure. Similarly, the data object envelope (OBJDSS) has a pre-specified format, and carries all objects except the commands and reply messages: An OBJDSS however may carry multiple objects;
(b) The codepoint of the root node;
(c) The length characteristic: The length characteristic includes descriptions for fixed length objects, variable length objects, objects with a maximum length, and objects with a minimum length.
2. Information Stored for Internal Nodes and Leaves (terminal nodes):
The following attribute information is stored for non-root nodes:
(a) whether the node is Required, Optional, or Ignorable;
(b) whether the node (and its descendents) are repeatable or not;
(c) the level or depth of the node in the tree;
(d) the length characteristic of that node.
The first attribute stored is the Required, Optional, or Ignorable attribute.
A Required attribute specifies that support or use of a parameter is required: when a parameter is specified as being required in a parameter list for a command, the parameter must be sent for that command. All receivers (of transmissions) supporting the command must recognize and process the parameter as defined. When specified in the parameter list of a reply message, the parameter must be sent for that reply message. All receivers must accept the parameter.
An Optional attribute specifies that support or use of a parameter is optional. When a parameter is specified as being optional for a parameter in a parameter list for a command, the parameter can optionally be sent for that command. All receivers supporting the command must recognize and process the parameter as defined and use the default value if it is not sent. When specified in the parameter list of a reply message, the parameter can optionally be sent for that reply message. All receivers must accept the parameter.
An Ignorable attribute specifies that a parameter can be ignored by the receiver of a command if the receiver does not provide the support requested. The parameter can be sent optionally by all senders. The parameter codepoint must be recognized by all receivers. The receiver can ignore the parameter value.
Next is the Repeatable or Not Repeatable attribute. A Repeatable attribute specifies that a parameter can be repeated. If it is specified as Not Repeatable it can't. There are no requirements that the elements of the list be unique, or that the elements of the list be in any order. The information stored for root and non root nodes is logically depicted in FIGS. 21-23.
For example, a top level node with the description "1,200C,★★★★" has a carrier of 1 (request), codepoint of hex`200C` and variable length (i.e., up to an unspecified limit).
In addition, a parameter, or internal node, with the following description: "RN2:2408,★255" means that the parameter is required, non-repeatable, has a codepoint of hex`2408` and has variable length of up to 255.
Ordering of the Parameters
In the embodiment described the parameters for each full tree are listed in a linear fashion; for example, for the tree depicted in FIG. 18, the ordering of the parameter definitions in the tree for depth first search is: N0, N1, L1, N2, N2.1, L2, N2.2, L3, N3, L4, N4, N4.1, N4.1a, L5, N4.1b, L6, N5, L7, where:
N stands for Node, and
L stands for Leaf.
The order of the tree is maintained. The tree can be reconstituted in a hierarchical form, since depth first search order was used, and depth information was maintained.
Other Parameter Orderings: Because all the valid orderings in which DDM parameters sent are all of the orderings of depth first search (not just those limited to the left-to-right notation convention) it is more convenient to store the definition in this manner. It would be possible, but more expensive to store them in another order. Additional information, e.g., parent information, would have to be added to the definition, so that the tree may be reconstructed from the linear form.
Retrieval Mechanism
In the embodiment of the invention described the retrieval mechanism is based on a simple search technique, a binary search. However, other suitable search methods can be used depending on the range of the codepoints, the values of the codepoints, the size of the forest to be implemented, etc.
DDM Dictionary Syntax
FIG. 19 depicts DDM dictionary definition syntax for commands, replies, and data using the embodiment of the invention described herein.
Interpretation Rules
The rules describing DDM Dictionary syntax can be interpreted as follows:
1. ":=" means "is defined by", e.g., A:=B means that A is defined by B.
2. "|" means logical or, e.g., A:=B|C, means that A is either defined as B or C.
3. Lower case characters represent terminal nodes of the definition and are defined as literals.
4. Upper case characters represent non-terminal nodes and are defined as a collection of terminals and non-terminals.
5. quotes: Items in quotes are literals. For example `B` means the letter B.
Acronyms & Syntax used in FIG. 19
Carrier indicates the DSS carrier
0 indicates the DSS carrier used for partial replies
1 indicates the DSS carrier field RQSDSS (request DSS), used for commands;
2 indicates the DSS carrier field RPYDSS (reply DSS), used for replies;
3 indicates the DSS carrier field OBJDSS (object DSS), used for objects;
Codept indicates the DDM codepoint: identifier for the DDM term;
Maxlen indicates the maximum length of the DDM term;
Minlen indicates the minimum length of the DDM term;
Level indicates the level of the DDM tree, i.e., indicates the level of nesting with the parameter;
Length is the length of the DDM parameter;
★★★★ means variable length;
$ signals the end of the definition;
LOWERA indicates a lower level architecture used by DDM. This allows for DDM to include other architectures.
The formal specification of the definition basically means the following (still referring to FIG. 19):
DDM -- ENTRY: Line 1 is the top level entry and defines the root node. The root node can have either a request, reply or data object envelope and this is specified by the Carrier. A carrier for the specific application has four possible values, 0 through 3, but this can be extended for other types of envelopes. In addition to the carrier, the root node information includes the codepoint, Codept of the node and the length specification of the root node (the length specification of the root node is usually variable length although this is not required. The length specification can specify a fixed length field, a maximum length field, a minimum length field or a variable length field). The root node can be composed of DDM objects, referred to as DDM -- PARMS (first line in the formal specification) or can be composed of objects of a lower level architecture and can either have itself a lower level data value (Line 2) or can be a collection of lower level objects (Line 3).
DDM -- PARMS: If the root node contains a collection of DDM objects and lower level objects, then this DDM definition is followed. The DDM object can either be (a) a terminal object (Line 4), with information such as required/optional/ignorable, repeatable/non-repeatable, level of the terminal object in the tree (with root node being level 1), the codepoint and length characteristic; (b) A terminal object with lower level object contents, with the same characteristics as the terminal object above (Lines 5-6); (c) Two DDM -- PARMS objects. This allows a DDM -- PARMS object to recursively define itself in order to allow more than one terminal object and more than one depth in the tree (line 7); (d) One DDM -- PARMS object. This is a syntactic trick to allow for the `$` which indicates the end of the object, and is required in the definition (Line 8).
LOWOBJ: Allows for the same structure as a DDM object and hence allows nesting and terminal nodes. The terminal nodes contain the same basic information as a DDM terminal node (Lines 9-11).
Line 12: A carrier can have values ranging from `0` to `3`. This can be expanded to more values as the need arises.
Line 13: The level of the parameter in the tree. The root has level 1 and its children have level 2. If a node has a level i then its children have level i+1.
Line 14: Codept indicates any valid DDM codepoint.
Line 15: Length characteristic for DDM: For example, it may take on the following values: (a) dddd, such as 1233, which means fixed length of 1233, (b) ★★★★, which means variable length, (c) ★maxlen, such as ★255 which means that the DDM object has a maximum length of 255, (d) minlen★, such as 255★, which means that the DDM object has length of at least 255. Note that there are only four characters for length. This can easily be expanded as needed
Lines 16 and 17: Specification of minlen and maxlen
Line 18: "roi" means that the parameter is either required, optional, or ignorable.
Line 19: "rn" means that the parameter is either repeatable or not.
Line 20: "d" is any valid digit from 0 to 9.
It is possible to modify the formal specification of the syntax in various ways, without changing the intent and the meaning of the invention. Various ways of modifying it include: (a) adding more carrier types, (b) adding more attributes to the root node, or to the parameter nodes; as more attribute characteristics are added to the architecture, more attribute place holders or more valid values may be added to describe DDM; (c) length specifications could change such as to add more digits to one length specification, or to add a parameter which has both minimum and maximum length restrictions. As DDM evolves, the formal specification for the dictionary syntax will evolve as well.
EXAMPLE
The files depicted in FIGS. 5a,b can be stored as follows:
______________________________________Request:1,200C,****/ON2:2110,0022/RN2:2113,0068/RN2:2114,0008/ON2:2132,0006$Command Data:3,200C,****/ON2:2412,****,LOWERA/RR3:0010,****/OR3:147A,****$______________________________________
There are two degenerate cases one can look at to compare DDSO with LCF and RSM. These are:
(a) a tree with one node: while DDSO stores the node in compact form, LCF stores one node in one file; LCF still needs to scan the file, but does not need to perform the assembly. RSM in the case of the tree with one node reduces to LCF, since there are no CASE statements associated with one node. Hence in the case of the tree with one node, DDSO still maintains its advantage of storage compaction, but is still slightly better than LCF and RSM in performance.
(b) A forest with one tree; in this case, DDSO avoids the binary search. LCF and RSM still have to construct the definition. Hence, in the case of a forest with one tree, the invention has advantages.
How DDSO Definitions are Used
The DDSO definitions are retrieved in both the parsing and the generation processing of DDM strings. Parsing means receiving a DDM string, checking its syntactic correctness and building the equivalent internal data structure for use by the local processor. Generation means receiving an internal data structure and building the DDM string using the definition tree. FIG. 20 depicts the parsing and generation process in a requester-server distributed system. An application program first submits a request in internal format.
(Step 1) The request is translated into the DDM string by the generation process (the generator consults the DDM Dictionary to do this).
(Step 2) Then, the request is sent to the server, which receives it. The parser translates the request into internal format by consulting the DDM dictionary for syntax verification.
(Step 3) Then, the internally formatted request is executed by the server. This can be one of various different suitable types of servers such as file servers, or database servers.
(Step 4) The server issues one or more replies in internal format, which are translated by the generator (Generator consults the DDM Dictionary) into a DDM string or strings.
(Step 5) DDM reply is sent to the source system.
(Step 6) Finally, the source system's parser translates DDM reply into internal format (Parser consults DDM Dictionary) and returns to the application program.
Conceptual Layering of DDM
In the specific embodiment described the parser and generator advantageously share a common design which stems from partitioning DDM data streams (DDM strings) into a series of layers.
The first, or topmost layer, Layer Zero, consists of a DDM Command or a DDM Reply, which constitutes a logical object. A request for parsing or generating must always come at layer 0.
Next is
Layer One, which is derived from breaking up this logical object into one or more Data Stream Structures, or DSSs (or data communications envelopes) which are linked to each other. For example, the DDM Command to execute an SQL Statement is accompanied by various parameters as well as command data (the SQL statement). DSSs can include a command part and zero or more command data parts; or, a reply part and zero or more reply data parts; or, one or more reply data parts.
Layer Two consists of the structural properties of a tree without looking at the specific values of the nodes within that tree. An example of a structural property of the tree is the length value at each node which is the sum of its children's length plus a constant (for its own length field and codepoint, or identifier).
Finally,
Layer Three: consists of each node of the DDM Tree. Each node has structural properties in the tree and valid required values. Examples of the structural properties within the tree include whether the node is required, optional, ignorable, repeatable, a collection, or a scalar. ("Collection" refers to an internal node, and "scalar" refers to a leaf node). Examples of values of the nodes: Leaf nodes carry values and these values carry certain restrictions. For example, leaves may be of certain data types, such as enumerated value data types or they may have certain length restrictions, such as maximum length. Non leaf nodes don't have values but have length restrictions.
SOFTWARE ARCHITECTURE FOR DDM PARSING AND GENERATION METHODS
There are three major levels of the DDM Parsing/Generation Process which correspond to the three layers mentioned above, and are depicted in FIG. 24.
The first level deals with the processing of a DDM Entry (Multiple Related Data Stream Structures): or relating two logical DDM Objects together. For example, a command must always be followed by command data if it has any. The "links" between the two Data Stream Structures (DSSs) (command, command data objects) are established by the processing of the DDM Entry. This level takes care of linking DSSs together, through various continuation bits, and ensures that the rules as defined by DDM architecture for linkage are enforced.
The second level involves processing one Data Stream Structure at a time. This level takes one of the DSSs and looks at its internal structure. Each DSS is composed of a tree. This level obtains the definition of the relevant DDM object from the DDM Dictionary, and then proceeds to step through the definition, and starts comparing it to the actual data received (parsing), or, uses it as a roadmap to generate the appropriate data stream (generation). While level 1 was concerned with the relationship between DSSs, level 2, the DDM layer, takes care of the relationships between the nodes within a DDM tree, with such activities as length checking for collection objects, etc.
The third level (the action level) concerns itself with individual nodes which include: Action Execution, Action Specifics, and a Link to a Lower Level Architecture. The Action Execution sublevel is the next natural level down and deals with individual nodes. These nodes have properties, such as: required, optional, ignorable, repeatable, etc. It is the responsibility of the Action Execution sublevel to ensure that required nodes are parsed or generated and that other structural properties of the codepoints are obeyed. The Action Specifics sublevel deals with the values in individual nodes. The nodes are either collection objects, (i.e., internal nodes: in which case they are composed of other DDM nodes), or they are scalars (i.e., leaf nodes). The collection objects have no specific values associated with them. The scalars do, and it is the responsibility of this sublevel of the hierarchy to ensure that the values parsed or generated are the correct ones. The length attribute is also verified against its corresponding definition in the dictionary. The third sublevel or the lower level architecture sublevel deals with more complex scalar objects defined in another architecture, such as the Formatted Data Object Content Architecture developed by IBM Corporation.
The common Parser and Generator design provides the following advantages including maintainability, generality, and non-recursive methodology.
Maintainability is due to the fact that changes in the syntax of DDM are only limited to the action specifics portion. For example, if a parameter changes, it is very easy to locate the unique instance of its action in the code. Also, the common logic makes it easier to maintain the code. The Parsing and Generation processes use common data structures, such as the Length Tree Data Structure.
The code is very general, in that changes in the dictionary are localized to the action specifics (Generality). One could merely change the action specifics part and have a Parser and Generator for a Distributed File System Application, for example. The structure of DDM is followed and hence changes can easily be incorporated.
The actions described above are for a Data Base Application. However, it would be relatively easy for a person skilled in the art herein to build a set of actions for another application of DDM and substitute the new set to achieve the intended results.
Another advantage of the use of the dictionary of the invention is that the method of use simulates recursion by having a completely expanded dictionary. That is, the DDM Tree is expanded in a depth-first search manner. Therefore, the method has the advantages of a recursive solution without the overhead of the actual recursion.
Advantages of DDSO
In terms of storage requirements DDSO shows useful advantages. The efficient utilization of storage is due to the fact that only essential information is retained. The dictionary is encoded into a specific format so that it will contain the definition in its most minimal form while still including information about all the nodes in the tree of the definition including the optionality information about the node, the node's length information, and the node's level information.
Also, there is only one dictionary access per top level DDM definition. One dictionary access gives access to the entire definition as opposed to the definition of the node only. By comparison, LCF requires as many accesses as the number of parameters in the tree. RSM requires one access per top level node, but only provides structural information for the top level node and not the entire definition tree.
In addition to being more storage efficient and requiring only one dictionary access to obtain the full definition, DDSO constructs the definition prior to compile time. Since the definition has been expanded prior to compilation, the recursive step is not done at run time which would be at the expense of the user. DDSO incurs the cost once per definition prior to compiling the code. DDSO uses binary searches into a table of top-level nodes. DDSO could also utilize other search methods, such as hashing etc. LCF and RSM appear to be limited to sequential search methods.
DDSO code is less complex. DDSO has a unique action for the same node and hence does not duplicate code unnecessarily. DDSO is independent of the programming language. Also, DDSO can use a table driven method while RSM has hardcoded programs. DDSO encodes the definitions as data. A change in DDM architecture would require RSM to change the program rather than just the data. For clarity, maintenance, and simplicity, the table driven approach has advantages. Also, the method is expandable for future use. DDSO appears to be independent of programming language, while RSM appears limited to the number of nestings of CASE statements allowed in the implementation of programming languages.
DDSO compacts the definitions, and defines a grammar to describe DDM. The expansion of the trees is done before compile time, and hence the recursive step of LCF need not be done for each DDM tree parsed or generated. DDSO is a table-driven method, in which the table contains the node identifier followed by a pointer to the already expanded definition.
DDM Dictionary Data Structure Example An example of a DDM dictionary according to the invention herein is depicted in FIGS. 17a-l. Some points to note about the example are:
1. Data Structures Used: In this example, a DDM Dictionary data structure and retrieval mechanism are discussed. It is composed of the following declarations:
______________________________________TABLE: a table containing: Specification and codepoint: used to search for a root level codepoint concatenated with the specification, which indicates: CD - command data, CP -command part, RD - reply data to distinguish between carrier types. Length of definition Pointer of definition: this points to the definition of the tree. This table is used for binary search. The specification and root level are listed in alphabetical/numerical order.TBLBASE: a pointer to the table used to remember the starting location of the table.TBL.sub.-- PTR: a pointer used to search through the tableDDM.sub.-- TBL: a template used in conjunction with TBL.sub.-- PTR to search in the table and obtain the necessary fields.______________________________________
2. Specific Method to Retrieve the Data:
(a) Find out part specification and codepoint in last four character positions.
(b) Do a binary search in the table to match desired codepoint. When found, then move to the definition buffer area.
The retrieval mechanism depicted in FIGS. 17k,l is based on a simple binary search. However, other search methods can be used to fit the particular application.
The above-described embodiments are merely illustrative of the application of the principles of the invention. Other arrangements may be devised by those skilled in the art without departing from the spirit and scope of the invention. | A method of creating a data transmission dictionary by deriving a group of one of more computer searchable definition trees from a first definition group of nodes defining portions of commands, replies, or data usable by a computer system, compacting each of the nodes by retaining only information necessary for the processing of data transmission streams according to the definition trees; assembling each definition tree by sequencing the compacted nodes in a linear form, starting with the root node of each of the definition trees, by placing information included in each compacted node in a resulting implemented dictionary; and by assembling each child node in the resulting implemented dictionary and assembling each of the child's child nodes in turn. The process of assembling a terminal node involves placing information included in the terminal node in the resulting implemented dictionary. | 8 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of and claims the benefit under 35 U.S.C. §120 of co-pending U.S. patent application Ser. No. 10/136,603 entitled “System and Method For Generating A Chronic Circuit Report For Use In Proactive Maintenance Of A Communication Network” and filed on May 1, 2002. This application also incorporates co-pending U.S. patent application Ser. No. 10/136,603 by reference as if fully rewritten here.
BACKGROUND
[0002] 1. Field of the Invention
[0003] This invention relates generally to telecommunication networks. More particularly, the invention relates to a system and method for proactively maintaining a telecommunications network.
[0004] 2. Description of the Related Art
[0005] Proactive maintenance in a telecommunications network allows network operators to anticipate where problems may occur in the future and act proactively to prevent some customer problems from occurring. Proactive activities may also allow a network operator to determine if and help ensure that network performance service level agreements (SLAs) are being met and will continue to be met. Proactive activities preferably include identifying current and potential bottlenecks, inefficient or poorly performing components, potential failures, and others. A current way in which proactive maintenance is performed involves generating reports relating to equipment that are generating errors and evaluating the reports to determine which equipment to proactively maintain.
SUMMARY
[0006] A system and method for generating a chronic circuit report for use in maintaining a communication network is provided. In accordance with one aspect of the invention defined by the claims, the method comprises the steps of searching a database for information regarding circuit exceptions reported in a communication system, compiling a listing of circuits and circuit exception information, prioritizing the listing of the circuits based on the circuit exception information, and generating a circuit exception report.
[0007] In accordance with another aspect of the invention identified in the claims, a computer-implemented system for identifying circuits in a communication network having chronic troubles is provided. The system comprises a searching module, a prioritizing module, and a report generator module. The searching module searches through a database in a network monitoring system to identify communication circuits in a communication network that have had exceptions reported against them. The searching module also identifies the number of exceptions of a plurality of types reported against the communication circuits. The prioritizing module prioritizes the communication circuits identified by the searching module. The report generator module generates a report that lists the communication circuits that had exceptions reported against them.
[0008] In accordance with another aspect of the invention identified by the claims, a system for monitoring end-to-end circuit exceptions in a communication network having a plurality of network elements is provided. The system comprises a storage area having a database for storing information regarding exceptions reported against circuits in the communication network, a circuit error posting subsystem for posting to circuit records contained in the database the information regarding exceptions reported against circuits, and a reporting subsystem. The reporting subsystem comprises a searching module, a prioritizing module, and a report generator module.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] In order that the invention identified in the claims may be more clearly understood, preferred embodiments of structures, systems and methods having elements corresponding to elements of the invention recited in the claims will be described in detail by way of example, with reference to the accompanying drawings, in which:
[0010] FIG. 1 is a schematic diagram of an exemplary section of a Local Access and Transport Area network;
[0011] FIG. 2 is a block diagram of an exemplary section of a Local Access and Transport Area network having a network monitoring system in communication with network elements;
[0012] FIG. 3 is a chart that illustrates a preferred circuit report;
[0013] FIG. 4 is a block diagram of an exemplary network section illustrating a plurality of circuits;
[0014] FIG. 5 is a block diagram that illustrates a preferred network monitoring system;
[0015] FIG. 6 is a flow chart that illustrates a preferred method for generating a circuit exception report; and
[0016] FIG. 7 is a flow chart illustrates another method for generating a circuit exception report.
DETAILED DESCRIPTION
[0017] To facilitate the understanding of the invention described by the claims, an exemplary portion of a telecommunication network is described. The invention described by the claims is not limited to use solely with this portion of a telecommunication network, and could be applied to similar portions of a network or other portions of a network without departing from the scope of the invention.
[0018] Referring now to the drawings, shown in FIG. 1 is an exemplary section of a LATA Local Access and Transport Area network 8 that provides a circuit 10 for communication between two locations, customer location A and customer location B. In the illustrated example, the circuit provides the customer with a first subscriber network termination interface (NTI) 11 and a second subscriber NTI 12 . Coupled to each NTI 11 , 12 , a subscriber may have various types of customer premises equipment (CPE) such as conventional telephones, facsimile machines, private branch exchanges, voice mail systems, key telephone systems, computers, modems, telephone answering machines, alarm systems, and radio control systems, as well as many other devices.
[0019] Coupled between each NTI 11 , 12 in the illustrated circuit 10 , are a central office (CO) 12 , a first field cabinet 14 , and a second field cabinet 16 . The CO 12 and each field cabinet 14 and 16 comprise various types of switching and transmission network elements (“NE”) that are configurable to provide the circuit 10 . Examples of network elements that may be located at the CO 12 include Multiplexers (MUXs) 18 , digital cross-connect systems (DCS) 20 , and other equipment. Examples of network elements that may reside in the cabinets 14 and 16 include coder/decoder (codec) equipment, multiplexers (“MUXs”) 24 , line interface units (“LIUs”), Optical network units (“ONUs”), digital loop carrier (“DLC”) equipment 22 , HDSL Line Units (“HLUs”), HDSL Remote Units (“HRUs”), and others.
[0020] As illustrated in FIG. 2 , a network monitoring (“NM”) system 26 is also typically employed to monitor the performance of the network 8 . The NM system 26 is one of the primary tools used in network maintenance. The NM system 26 typically establishes a permanent virtual channel (PVC) 28 with each NE 30 for monitoring both equipment performance and facilities performance. If a network system problem, such as an interruption to customer services is detected, maintenance technicians can be provided with network performance data from the NM system 26 to use in isolating and correcting the problem.
[0021] The preferred NM system 26 in the illustrated embodiment is the Telcordia Network Monitoring and Analysis (“NMA™”) system although other NM systems could be employed. The NMA™ system 26 monitors the network 8 through, among other things, communicating with a large variety of NEs 30 and Operations Systems (“OSs”) (not shown). The NMA™ system 26 can monitor and analyze problems on various types of networks, including Common Channel Signaling (CCS)/Signaling System 7 (SS7) networks, including class five switches, Synchronous Optical Network (SONET)/Synchronous Digital Hierarchy (SDH) networks (with TMN/Q3), Microsoft, wireless and broadband networks, and data communications and IP-based networks. The NMA™ system 26 is a client/server application that runs on a distributed architecture with a fault-tolerant server that services multiple operator stations.
[0022] Each of the NEs 30 report status and error messages to the NMA™ 26 on demand or on detection of a condition that requires the reporting of a message. The messages could relate to equipment inside of the NE, such as a circuit board, or something external to the NE that the NE can sense, such as a loss of signal on a channel serviced by the NE. Thus, the NEs report equipment alarm and facility alarms or line oriented alarms and equipment oriented alarms. The messages are sent via a NE's PVC to the NMA™ 26 for further processing.
[0023] Many error messages reported to the NMA™ 26 result in no action being taken. Random errors occur and may not equate to a loss of service to a customer. Consequently, many error messages are not acted upon unless there has been a complaint by a customer.
[0024] Most maintenance activities with respect to the network 8 are performed on a reactive basis. For example, when a customer problem is detected, network operators react to the problem and dispatch service technicians to determine and isolate the problem. Having the ability to proactively maintain the network is desirable.
[0025] Proactive maintenance allows the network operators to anticipate where problems may occur in the future and act proactively to prevent some customer problems from occurring. Proactive activities may also allow a network operator to determine if and help ensure that network performance service level agreements (SLAs) are being met and will continue to be met. Proactive activities preferably include identifying current and potential bottlenecks, inefficient or poorly performing components, potential failures, and others.
[0026] Illustrated in FIG. 4 is an exemplary report from an exemplary reporting system that can be implemented by the NM system 26 for reporting circuit errors to the network operators to allow the network operators to proactively maintain the network 8 . The reporting system accumulates per circuit the number of errors experienced by each circuit over a period of time. Preferably the report is a daily report that, everyday, lists the number of errors that were experienced by each circuit during the previous day. Preferably, the report also lists the number of errors experienced by the circuit during the day prior to the previous day. Preferably, the circuits listed on the report are those circuits that experienced errors during at least one of the prior two days. If a circuit did not experience any errors in the prior two days then it preferably would not be listed on the report. The reporting system prioritizes the circuit listing based on a prioritization scheme and provides the prioritized list to network operators to allow the network operators to attempt to solve issues on customer circuits in an effort to eliminate problems before the issues become problems or before a customer notices a problem.
[0027] The reporting system preferably categorizes error messages on the report as either events, minor alarms, major alarms or critical alarms. The reporting system also reports an accumulated total number of errors for the day and the accumulated total number of errors for the prior day.
[0028] The reporting system uses a prioritization scheme to prioritize the circuit listing. According to the preferred prioritization scheme, the circuit(s) with the largest number of critical alarms is (are) listed first, then the circuit(s) with the largest number of major alarms is (are) listed next, followed by the circuit(s) with the largest number of minor alarms, and finally the circuit(s) with the largest number of events. Alternate prioritization schemes could also so be employed such as prioritization based on the total number of errors for the day or some other criteria.
[0029] Illustrated in FIG. 4 is an exemplary block diagram of a portion of a LATA network that provides services to four customer locations. Customer location # 1 is provided with a circuit to customer location # 2 (circuit # 1 ), a circuit to customer location # 3 (circuit # 2 ), and a circuit to customer location # 4 (circuit # 5 ). Customer location # 2 is provided with a circuit to customer location # 1 (circuit # 1 ) and a circuit to customer location # 4 (circuit # 3 ). Customer location # 3 is provided with a circuit to customer location # 1 (circuit # 2 ) and a circuit to customer location # 4 (circuit # 4 ). Customer location # 4 is provided with a circuit to customer location # 2 (circuit # 3 ), a circuit to customer location # 3 (circuit # 4 ), and a circuit to customer location # 1 (circuit # 5 ).
[0030] The reporting system could be used to chart errors occurring in each of the circuits and provide a report to a service operator. The reporting system could report to the service operator, for example, that circuit # 4 is experiencing some errors that may be worth further investigating before service on circuit # 4 is severely affected.
[0031] Illustrated in FIG. 5 is an exemplary reporting system that could be implemented within the NM system 26 . In the description that follows the term module is used. The term module as used herein is a generic term used to describe any entity such as hardware, software, firmware, or a combination of the above that causes the execution of some function.
[0032] Preferably, associated with the NM system 26 is a storage area 40 and more preferably a network architecture database 42 . The network architecture database preferably is used to store a number of data records including a circuit record 44 for each provisioned circuit within the network.
[0033] The NM system 26 includes a circuit error posting subsystem 46 for posting circuit errors to the circuit record 44 that corresponds to the circuit that experienced the error. The NM system 26 also includes a reporting subsystem 48 that produces a prioritized report of circuits experiencing errors.
[0034] The circuit error posting subsystem 46 receives error messages sent from NEs and preferably temporarily stores the messages in a storage area 50 . A message parser module 52 determines, by examining the error message, which circuit the received error message relates to. A data record manipulator module 54 , using the output from the message parser module 52 , posts the error message to the circuit record that corresponds to the circuit that the error message pertains to. The circuit error posting subsystem 46 performs this function whenever a circuit error message is received.
[0035] On a periodic basis, preferably daily, the reporting subsystem 48 produces a prioritized report of circuits experiencing errors during the previous period. The reporting subsystem 48 preferably includes a searching module 56 that on a daily basis searches through the circuit records using established search criteria 58 . Preferably the search criteria 58 causes the searching module 56 to identify circuit records that indicate that the associated circuit experienced some kind of error either the prior day or the day prior to that.
[0036] Circuit record error information from the circuit records 44 identified by the searching module 56 is preferably outputted to a storage area 60 . Preferably, the information outputted includes the circuit identification, the number of errors of each type experienced by the circuit during the previous day, and the total number of errors experienced by the circuit the day prior to the previous day. Preferably, a data record parser module 62 retrieves the circuit error information from the circuit records identified by the searching module 56 and outputs the information to the error information storage area 60 . The storage area 60 preferably is a file, but optionally could be a location in memory, and/or a location in a database, or others.
[0037] Preferably, a prioritizing module 64 prioritizes the error information in the storage area in accordance with a prioritizing algorithm 66 and a report generator 68 generates a report 70 . The report generator module 68 , preferably, generates a report 70 in some form, such as a visual on screen report or a printed report, using the prioritized circuit exception information. The circuit generator module 68 optionally may have inputs that allow a user to select report options 72 that allow the generated report 70 to be customized.
[0038] Illustrated in FIG. 6 is an example of a method for generating a circuit exception report. The method assumes that circuit exceptions have already been reported to the NM system 26 and have been recorded. In step 100 , a search is made in the database or file where the circuit exceptions have been recorded. Preferably, the search results in identifying circuits that experienced errors and the errors experienced during the two prior days.
[0039] In step 102 , the retrieved information is tallied, organized and recorded to produce a file, data structure, or some other information holding structure that includes for each circuit information relating to the exceptions experienced by that circuit. Preferably the exception information includes the number of the various types of exceptions experienced in the preceding day and the total number of exceptions experienced in the day prior to the preceding day. If a circuit did not experience any errors in the two preceding days, preferably the circuit was either not included in the tally or removed from the tally.
[0040] In step 104 , the circuit exception information file was prioritized according to a set of prioritization rules. The preferred prioritization rules provide that the order be determined first based on the number of critical exceptions experienced, then based on the number of major exceptions experienced, then based on the number of minor exceptions experienced, and finally based on the number of events experienced. Other prioritization rules, however, may be implemented.
[0041] In step 106 , a circuit exceptions report is generated from the prioritized information. The report could take on many different forms. It could include some or all of the error information for each circuit. It could displayable via a computer screen or be in the form of a printed report, or both. It could be in the form of a graphical display or a non-graphical display. The exception report could categorize the various types of exceptions, or alternatively tally the number of each type of exception experienced per circuit.
[0042] Finally, network operator personnel can use the generated report to perform proactive maintenance on sections of the network or on various circuits identified by the circuit exceptions report.
[0043] Illustrated in FIG. 7 is an example of another method for generating a circuit exceptions report that can be used by maintenance personnel in performing network maintenance. In step 110 , circuit exception information is stored in a database. In step 112 , exception information is retrieved from the database. In step 114 , the retrieve information is organized via affected circuit. In step 116 , the organized information is categorized and tallied such that for each circuit a count is generated that corresponds to the number of exceptions that circuit experienced for that category of exception. In step 1 18 , the categorized and tallied circuit exception information is prioritized in accordance with prioritization rules. Finally, in step 120 , a report is generated containing the prioritized circuit exception information. Other variations from these systems and methods should become apparent to one of ordinary skill in the art without departing from the scope of the invention defined by the claims.
[0044] The embodiments described herein and shown in the drawings are examples of structures, systems or methods having elements corresponding to the elements of the invention recited in the claims. This written description and drawings may enable those skilled in the art to make and use embodiments having alternative elements that likewise correspond to the elements of the invention recited in the claims. The intended scope of the invention thus includes other structures, systems or methods that do not differ from the literal language of the claims, and further includes other structures, systems or methods with insubstantial differences from the literal language of the claims. Although the embodiments have been described with reference to a Local Access and Transport Area network, it is contemplated that the invention could be applicable to devices and systems that use other transport network configurations. | A method for generating a chronic circuit report for use in maintaining a communication network is provided. The method comprises the steps of searching a database for information regarding circuit exceptions reported in a communication system, compiling a listing of circuits and circuit exception information, prioritizing the listing of the circuits based on the circuit exception information, and generating a circuit exception report. | 7 |
TECHNICAL FIELD
The present invention relates to a method and apparatus for rating Uniform Resource Locators (URLs). More particularly, the invention relates to a method and apparatus for rating URLs in a client-server based architecture according to which a multiplicity of clients request URL ratings from a common server or server set.
BACKGROUND
Whilst providing a great many benefits to individuals and organisations, the Internet can be a source of both hidden and known dangers. On the one hand, much of the content available on the Internet is of an undesirable nature, whilst on the other web pages can be a source of malware including spyware, trojans, viruses, etc. One mechanism for defending against these problems is to perform a rating on Uniform Resource Locators (URLs) entered into a web browser on a client terminal, and to present the rating information to the user before downloading the associated web page and/or filter access requests in dependence upon the rating results.
US2008/0163380 describes one such approach involving URL ratings. This involves providing a URL Rating Server which maintains a database of known URLs and their ratings. Client terminals request ratings from the Rating Server, for example prior to downloading a web page. In order to reduce waiting times on the client side, a URL cache is built up in the client terminal based both on previously accessed and trusted URLs, and pre-populated URL rating data obtained, for example, based on a user's profile.
Known approaches to providing URL ratings using a client-server approach suffer from the disadvantages that the database of rated URLs must be extremely large, and that it is extremely difficult to maintain a reliable database given the ever-changing nature of the Internet. The massive growth in web 2.0 sites in particular causes a significant problem for conventional URL rating systems given that dubious and dangerous content can be introduced to the Internet and subsequently removed over extremely short time periods. In fact, known approaches are to a large extent ineffective in view of the changing use patterns now seen with the Internet.
SUMMARY
It is an object of the present invention to overcome or at least mitigate the above noted disadvantages of known YRL rating methods. This is achieved, at least in part, by seeking to identify rated URLs that match component parts of URLs that clients seek to rate. Such rated URLs may be provided to clients to transfer at least a part of the computational load, required to rate a URL, from a back-end server to the clients.
According to a first aspect of the present invention there is provided a method of providing rating information in respect of Uniform Resource Identifiers to a client terminal, the method comprising:
1) identifying a Uniform Resource Identifier at the client terminal; 2) sending a first query to a rating server over an IP network, the query including as a query string a first component of the identified Uniform Resource Identifier or a derivative of that first component; 3) receiving the first query at the rating server and determining whether or not a rating exists for the query string; 4) sending a response including a determined rating, or an indication that no rating exists, to the client terminal; 5) receiving the response at the client terminal and, if a rating included in the response so indicates or if the response otherwise so indicates, then sending a further query to the rating server, the further query including as a query string said first component and a second component of the identified Uniform Resource Identifier, or a derivative of the first and second components; 6) repeating steps 3) to 5) one or more times as required, adding for each iteration a further component to the query string.
Embodiments of the present invention may, in a large number of cases, reduce the time taken to rate a URL. Rating of a full URL may be required in only a limited number of cases.
The queries sent to the rating server may contain derivatives of the respective query strings, each derivative being obtained by applying a hashing function to the corresponding query string.
Said first component may comprises a registered domain name or registered IP address. Said second and any further component may comprise further sub-components prefixed to said first component.
The method may involve, at the rating server, if it is determined that a rating exists for the query string and that a second or further component is required to refine the rating, including in the response a format definition for a further query.
The method may involve, upon receipt of a response at the client terminal, caching in a local cache any determined rating together with the associated query string or derivative. At the rating server, if it is determined that a rating exists for the query string and that a second or further component is required to refine the rating, a format definition for a further query may be included in the response and additionally cached in the local cache the format definition.
The method may comprise, between steps 1) and 2), querying said local cache to determine whether or not it contains an entry for a component of the Uniform Resource Identifier or a derivative of that component and,
if not, then including that component or its derivative as said first component or its derivative in said first query, and, if so, then presenting the rating to a user and/or constructing said query string of said first query according to a specified format definition.
In an embodiment of the invention, the client terminal comprises a web browser and the method further comprises displaying in a web browser window a determined rating. The method may comprise the further steps of:
if a rating received by the client terminal indicates that the Uniform Resource Identifier is trusted, then downloading the data from that Uniform Resource Identifier into a web browser window, and if a rating received by the client terminal indicates that the Uniform Resource Identifier is malicious, then blocking the downloading of data from that Uniform Resource Identifier into a web browser window.
The Uniform Resource Identifier or a derivative of the Uniform Resource Identifier may be included in said first query sent to the rating server. In this case, the method may comprise, at said rating server, determining whether or not a rating exists for the Uniform Resource Identifier or its derivative prior to determining whether or not a rating exists for the query string and, if so, then returning a response containing the rating, to the client terminal.
According to a second aspect of the present invention there is provided a method of providing rating information in respect of Uniform Resource Identifiers to a client terminal. The method comprises receiving at the client terminal from a network server, ratings in respect of Uniform Resource Identifiers, and caching the received ratings at the client terminal within a client cache. The method further comprises for a Uniform Resource Identifier identified at the client terminal for which a rating is required,
querying the client cache to determine whether or not it contains a rating for a Uniform Resource Identifier matching a first component of the identified Uniform Resource Identifier, in dependence upon the result, extending the first component with a second component of the identified Uniform Resource Identifier and either conducting a further query of the client cache with the extended Uniform Resource Identifier or sending a query to the rating server.
The extended Uniform Resource Identifier may correspond to the identified Uniform Resource Identifier.
The method of the second aspect may comprise further extending the extended URI in dependence upon further results and repeating the query of the client cache or sending a query to the rating server.
A query sent to the rating server may contain the complete identified Uniform Resource Identifier.
According to a third aspect of the present invention there is provided a computer program for causing a computer to perform the steps of:
1) identifying a Uniform Resource Identifier at the client terminal; 2) sending a first query to a rating server over an IP network, the query including as a query string a first component of the identified Uniform Resource Identifier or a derivative of that first part; 3) receiving a response at the client terminal and, if a rating included in the response so indicates or if the response otherwise so indicates, then sending a further query to the rating server, the further query including as a query string said first component and a second component of the identified Uniform Resource Identifier, or a derivative of the first and second components; 4) repeating steps 2) and 3) one or more times as required, adding for each iteration a further component to the query string; 5) depending upon a final rating or the absence of a rating, either allowing the client terminal to access data identified by the Uniform Resource Identifier or preventing access to that data or requesting a user decision.
According to a fourth aspect of the present invention there is provided computer-readable recording medium having stored thereon instructions for causing a computer to:
1) identify a Uniform Resource Identifier at the client terminal; 2) send a first query to a rating server over an IP network, the query including as a query string a first component of the identified Uniform Resource Identifier or a derivative of that first part; 3) receive a response at the client terminal and, if a rating included in the response so indicates or if the response otherwise so indicates, then sending a further query to the rating server, the further query including as a query string said first component and a second component of the identified Uniform Resource Identifier, or a derivative of the first and second components; 4) repeat steps 2) and 3) one or more times as required, adding for each iteration a further component to the query string; 5) depending upon a final rating or the absence of a rating, either allow the client terminal to access data identified by the Uniform Resource Identifier or prevent access to that data or request a user decision.
According to a fifth aspect of the present invention there is provided method of providing ratings in respect of Uniform Resource Identifiers to client terminals, the method comprising:
1) maintaining at or in association with a server, a cache containing ratings for Uniform Resource Identifiers; 2) receiving at the server, from a client terminal, a query containing a queried Uniform Resource Identifier; 3) identifying a first component of said queried Uniform Resource Identifier and determining whether or not said cache contains an entry for a Uniform Resource Identifier matching said first component; 4) if the cache contains an entry which indicates that a further Uniform Resource Identifier component is required to rate the queried Uniform Resource Identifier, then identifying such a second component and determining whether or not the cache contains an entry for a Uniform Resource Identifier which matches said first and second components; 5) repeating step 4) as required with the inclusion of further components until either a final rating is obtained or it is determined that the queried Uniform Resource Identifier cannot be rated; 6) returning the determined ratings to the client terminal including any ratings determined for intermediate Uniform Resource Identifiers.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates schematically a network architecture over which a URL rating service is provided;
FIG. 2 is a flow diagram illustrating a first URL rating procedure involving a rating server parsing a URL for previously rated components;
FIG. 3 illustrates a sequence for performing an improved rating procedure in which a client terminal parses a URL and sends sub-queries to a rating server in respect of URL components;
FIG. 4 illustrates schematically a client terminal configured to provide URL rating information; and
FIG. 5 illustrates in more detail the procedure of FIG. 3 .
DETAILED DESCRIPTION
There is illustrated in FIG. 1 a typical client-server architecture for providing a URL rating service. A multiplicity of client terminals 1 (which may be mobile phones, PDAs, laptops, PCs etc) are able to access the Internet 2 via some appropriate access network(s) (not shown in the Figure). Also coupled to the Internet is an ORSP FE (URL) rating server 3 operated by a third party service provider, e.g. a vendor of antivirus and security products and services. Each terminal is typically provided with a web browser that allows a user to download, view, and interact with web pages. A web browser is also provided with certain new functionality for optimising the rating process and enhancing the user experience. This functionality will now be described.
Every URL is made up of some combination of the following: a scheme name or resource type, a registered domain name or Internet Protocol (IP) address, the port number, the pathname of the file to be fetched or the program to be run, the query string including query parameters, and, with html files, an anchor for where the page should be displayed at. The combined syntax may be as follows:
resource_type://domain:port/filepathname?query_string#anchor.
As has been noted above, even where a domain name or (IP) address is trusted, as is the case for example with “youtube.com” or “wikipedia.com”, content behind the domain name or IP address may not. It is also possible that the same web page may be pointed to by a (large) number of different URLs.
It is possible to reduce the number of rating queries that a client sends to the URL rating server by identifying those URL components behind which all URLs are trusted (or not trusted), and caching these at the client. When a user enters a URL into a browser, appropriate components of the URL are compared against the cached components. If a match is found, the cached rating can be presented to the user, or filtering action taken, without the need for the client to send a query to the rating server. Only if a match is not found need a query be sent.
It would be possible to build the cache at the client by causing the client to send a complete URL to the rating server in the event that a match is not found. This process is illustrated in FIG. 2 , where (at steps 1 to 3, 9 and 10) the client terminal determines whether a local URL rating cache contains an entry for a component of the URL. If not, the client sends the URL to the rating server (step 4). The rating server could then split the URL into various components and compare those components against the contents of its database (step 5). The rating server would then return (step 6) to the client one or more components together with their ratings. The results are received and cached by the client (step 7), and the URL allowed or blocked accordingly (step 8). So, for example, if a user enters the URL:
http://www.marks-clerk.com/uk/attorneys/publications/articles.html
and no matches for the URL or its component parts are found in the local cache, the URL is sent to the URL rating server. In this case, the rating server parses the URL and determines that all URLs behind the “marks-clerk.com” domain level are trusted, and returns the result to the client. It is not necessary that the URL rating server maintain any rating data for specific URLs behind the marks-clerk.com domain level. The same is true for a malicious domain name, i.e. it is only necessary to maintain an entry for the domain level and not for any URLs behind that domain level. For a domain level that is itself trusted but for which URLs behind the domain level are not, e.g. “youtube.com”, the rating server should maintain ratings for those URLs (at least to a level where trust/non-trust has been established).
Improved lookup speeds may be obtained by storing hashes of URL components, and generating corresponding hashes from the received URL. The client cache also contains hashes. The client may, in addition to the plaintext URL, include in the query a hash of the URL components up to the point that it does not find a match in the local cache. The rating server then commences the search from that hash onwards. Only matches that are not previously known to the client are returned to it by the rating server.
In order to provide a very quick initial check, the client may send a hash of the complete URL to the rating server together with the plaintext URL. The rating server performs a quick search for the hash, and if the result is that the URL is trusted or not trusted, this is returned immediately to the client. Only if a match for the hash is not found by the rating server is a search performed using the URL components.
Whilst this approach may work in principle, in practice it opens a security threat as it is necessary for the client to send the complete URL in plain text in order to allow the URL rating server to parse the URL. In some instances, a URL may contain sensitive data such as a user's bank username and password. Whilst some approaches to URL rating require that the client cipher the sent URL, e.g. by applying a hashing function over the URL and sending only the result, this is not possible with the approach described in the preceding paragraph as the URL rating server will be unable to parse the URL components where the URL is previously unknown to the rating server. If ciphering is used, then the rating server must store a rating for each and every (rated) URL.
A solution to this problem is to break up the URL query into a number of sub-queries. This approach is illustrated in FIG. 3 , where a user first enters a URL (step 100 ) into the address line of the browser (or clicks on a web link). In the case of the example considered above, and again assuming that the client, using the client cache, is unable to rate the URL, the client determines (step 101 ) that it must send to the rating server a query containing the domain level “marks-clerk.com”. The client applies a rule set in this step in order to take account of hierarchical top level domain name structures such a “.co.uk”. Rather than send the domain name part in plain text, the client sends only a hash of the component (step 102 ). Upon receipt of the query, an ORSP Front End (FE) at the rating server compares (step 103 ) the received hash against a database of hashes corresponding to rated URLs. In this example, the hash of “marks-clerk.com” is present in the database, together with a “trusted” rating. The rating server responds to the client (step 104 ) with the rating. The client presents the rating to the user and downloads the requested web page (step 105 ). In addition, the hash of the domain name part is stored, together with the rating, in the client cache (step 106 ). The user can now freely surf all URLs behind the “marks-clerk.com” domain without any further queries having to be sent to the URL rating server.
Consider now the case where the user enters a URL of a community (web 2.0) website into the browser. The following sequence illustrates such a situation:
1. The user goes to http://www.youtube.com/watch?v=1234. 2. The client queries the root “.” domain with the client cache. The client cache maintains a rule set for handling such queries. In this case, it returns an instruction to query again with the format “<top-level domain>”. 3. The client queries the client cache again using the “.com” top level domain, and the client cache returns an instruction to query again with the format “<xxx>.com”. 4. The client queries the client cache again using the “.youtube.com” domain. 5. The client cache returns the result that a hash of the domain level is not contained within the cache. 6. The client then forwards the query to the ORSP FE server, which returns the answer that the domain level “*.youtube.com*” is trusted by default, but requesting the first part of the path”. 7. The client forwards a query to the ORSP FE server containing a hash of “*.youtube.com/watch*”, and receives a response that “*.youtube.com/watch*” is trusted by default, but requesting the ‘v’ parameter”. 8. The client forwards a query to the ORSP FE server containing a hash of “*.youtube.com/watch?v=1234*”, and receives a response that “*.youtube.com/watch?v=1234*” is malicious. 9. The client stores each response in the client cache (including the hash and the associated rating) and returns the final response to the browser plug-in 10. Subsequently, each time the user surfs to “youtube.com” or a video under the domain level, only a single query need be sent to the ORSP FE server relating to the video in question.
FIG. 4 illustrates schematically a client terminal 10 suitable for use with the approach described above. By way of example, the terminal may be a PC, laptop computer, or mobile phone. It comprises a display 11 , a user input unit 12 , for example a keyboard, and an Internet interface 13 . The terminal further comprises hardware and software components 14 for implementing a web browser 15 , a URL rating specific browser plug-in 16 , an ORSP client 17 , and a memory cache 18 available to the ORSP client. The browser plug-in 16 is configured to implement the ORSP client functionality described above, whilst the memory 18 is configured to store the client cache.
Considering the components of the client 10 in more detail, the browser plugin 16 represents a “thin” component whose role is to identify and extract URLs from the browser 15 , pass queries to the ORSP client 17 , receive rating responses from the ORSP client, and update the browser display according to received ratings (including downloading/blocking web pages). The ORSP client 17 is responsible for parsing URLs, hashing components, querying the local cache 18 , and querying the rating server. The ORSP client may be a service provided on the Windows™ platform, and communicates with the browser plugin via an appropriate Application Programming Interface (API). The local (client) cache is stored by the ORSP client 17 in the memory cache 18 .
FIG. 5 illustrates signalling associated with this example, where the browser, browser plug-in, ORSP client (NRS-ORSP-Adapter), and client cache are all software components within the client, and the FE-Server and FE DB (database) are components, possibly distributed, of the rating server. In this example, a redirect message causes the ORSP client to re-query either the local cache or the rating server.
It will be appreciated that anyone snooping traffic between the client terminal and the rating server will only see hashed URL components, and not the components themselves. In the event that the rating server possesses a rating for a received hash, the rating server will be able to identify the corresponding URL component. In that case, it is unlikely that disclosure of the URL component is of concern to the user. Sensitive URL component are very unlikely to be know to the rating server.
It will also be appreciated by the person of skill in the art that various modifications may be made to the above described embodiment without departing from the scope of the present invention. For example, an initial sub-query sent from the client to the rating server may additionally include a hash of the complete URL. The rating server may then perform an initial “quick search” for that hash, returning a result immediately to the client if a rating for that URL exists. Only if a rating is not found does the server proceed to perform a look-up based on the domain level.
The ORSP client may be implemented as a standalone application on the client terminal on the client terminal. Alternatively, the ORSP may be implemented as a browser plugin, applet, etc.
The URL rating server may maintain a set of rating categories indicative of the trust associated with a rated URL. For example, the following six categories may be used:
1 Untested [GRAY] 2 Malicious [RED] 3 Unsafe [RED] 4 Suspect [YELLOW] 5 Safe [GREEN] 6 Trusted [GREEN]
The colour associated with each category defines a colour that is displayed in a “traffic light” trust indicator added to the browser buttons by the ORSP client.
A rating provided to the client by the URL rating server may include a “time-to-live” (TTL) value. This indicates to the client a duration for which the rating can be trusted, and is stored in the client cache. When a URL entered into the browser matches or includes a component that matches a hash for which the TTL has expired, the client will repeat the query procedure with the rating server, updating the cache entry according to the result. The client may also periodically initiate updates of expired cache entries.
Critical cache updates may be pushed to the client by the rating server. This may apply for example to newly discovered malicious domain names. Alternatively, such critical updates may be provided en bloc the next time that a client makes an ordinary query to the rating server.
It will be further appreciated that the rating procedure described here may be applied to rate URLs associated with application/services other than a web browser. For example, the procedure may be applied to rate URLs and web data contained within emails. In this case, a thin “plugin” type component may be implemented in an email client such as Microsoft Outlook™, with the component communicating with the ORSP client. The ORSP client may be shared by multiple applications and services. | A method of providing rating information in respect of Uniform Resource Identifiers to a client terminal. The method includes identifying a Uniform Resource Identifier at the client terminal, sending a first query to a rating server over an IP network, the query including as a query string a first component of the identified Uniform Resource Identifier or a derivative of that first component, and receiving the first query at the rating server and determining whether or not a rating exists for the query string. A response is sent by the server to the client terminal, the response including a determined rating, or an indication that no rating exists. The response is received at the client terminal and, if a rating included in the response so indicates or if the response otherwise so indicates, then a further query is sent to the rating server, the further query including as a query string said first component and a second component of the identified Uniform Resource Identifier, or a derivative of the first and second components. The steps of receiving the first query at the rating server, sending a response, and receiving the response at the client terminal, are repeated one or more times as required, adding for each iteration a further component to the query string. | 7 |
This invention relates to a method and apparatus for handling electrical connectors of the type which are provided in a family of connectors having numerous positions for terminals which are preloaded into plastic housings to form an assembly. The method and apparatus of the invention involve feeding and indexing of the connector housings, termination of wires within the terminals thereof sequentially, and loading said terminals after termination into the housings while at the same time effecting a bending of the carrier strip which connects the terminals together.
BACKGROUND OF THE INVENTION
The present invention deals with an electrical connector of a type which is provided in a form which embraces an electrical terminal having a front end adapted to mate with a further terminal such as a post and a rear end adapted to be terminated to an insulated electrical wire, the terminated terminal being inserted into a plastic housing which serves to insulate the terminal from surrounding terminals and the conductive elements of circuits and components. The connector involved typically comes in a family wherein the connector housing may accommodate 2, 4, 6, 8 or as many as 30 or more terminals in separate cavities in plastic housings which have an appropriate number of terminal positions. This means automatically that the housings of the connector family are of different dimensions as related to the number of positions involved, 2, 4, 6, 8 and so forth. In the particular situation here involved, the matter is complicated by virtue of the fact that the connector family, in addition to having multiple positions, comes in more than one style with the dimensions of the two styles adding a second and perhaps a third set of dimensions which have to be dealt with. As a general rule, when connectors of the foregoing type are handled by individual operators, the operator performs the function of adjusting the tooling in accordance with the dimensions of the connector and terminal involved. In the present case, the invention embraces an operator assist machine which itself indexes and fixtures the connector preparatory to wire termination, assists in the termination of the wire in the terminal, and feeds the connector out from under the terminating tooling. As can be appreciated with indexing and feeding mechanisms having fixed displacement motions and dimensioned parts, it is usually necessary for an operator to physically make adjustments as between connectors of differently numbered positions or dimensions and particularly, with respect to connectors of different physical shapes. This creates a need frequently for a readjustment or fine tuning of the machine, all of which takes time and particularly skilled labor and in general, results in a lower productivity than if such can be accommodated without the need for adjustments as between connectors of different positions or dimensions.
A second aspect of the invention relates to maintaining the dimensional integrity of terminals and housing elements to allow a precision termination in an assembly of parts which must be eventually fitted together but which initially must allow access to a portion of the terminal for termination which portion is subsequently covered over by the housing of the connector. This problem is exacerbated when the critical elements of the connector housing and terminal are quite small, the center-to-center spacings are also quite small and the practical tolerances of parts have to be made consistent with mass production and low cost of units to meet market demands. In this regard, it has been found useful to provide assemblies of terminals having the carrier strips formed of the metal from which the terminals are made, left attached to thus hold the terminals on the center-to-center spacings as carried in the dies of manufacture, the source of very tight tolerances indeed when compared with single loose piece terminals.
This practice leaves the carrier strip attached until a time after the terminals have been terminated to electrical wires and requires that the carrier strip be removed therefrom so that the individual terminals will be individually isolated in an electrical sense. Additionally, the terminals have to be loaded into their respective cavities or passages within the housings of the connector, again calling for certain dimensional integrity in terms of the relative position of portions of the terminals and portions of the housing, wires terminated in the terminals, all of which is difficult to control without, in normal cases, machines of substantial complexity, tight tolerances and numerous facilities for adjustment of engaging surfaces. A further problem with assemblies of the type just discussed has to do with the removal of the carrier strip following termination and in conjunction with the insertion of the terminals into the housing.
The background to appreciate is one of dealing with very small metal and plastic parts made to have tolerances as wide open as possible and at the same time providing an operator assist machine and method for handling such assemblies of housings and terminals without undue complexity or need for constant tuning and adjustments, all of which lead to poor productivity. As can be appreciated by those skilled in the machine arts, the provision of parts to be worked upon or assembled wherein the parts are of constant and fixed dimension, tightly controlled, vastly simplifies machine design, construction, and maintenance. On the other hand, variation in dimensions either caused by loose tolerances associated with lower costs or dimensional variations deliberately designed into the part or parts for whatever reasons, including as in the present case, a desire to accommodate connectors having a widely varying number of terminal positions as well as connectors having different exterior designs creates a difficult problem.
SUMMARY OF THE INVENTION
This invention relates a method and a machine which accommodates connectors having a relatively large number of positions with varying dimensions and styles, the connectors being of the type wherein electrical terminals are partially preloaded into connector housings to form an assembly. The machine serves to index the connectors to provide alignment for termination of the connector terminals to conductor wires through the use of a novel pawl structure capable of accommodating to the differently arranged exterior surfaces of the housings while effecting an incremental displacement of such connectors which is constant throughout the range of numbers of positions and styles of the connector housings. It does this by providing a series of steps on the end of the pawl feed finger and biasing such feed finger downwardly to "find" the proper or available surface of the connector housing. This indexing allows a precision termination to the terminal of a conductor wire loaded therein by an operator with the terminal during termination being dimensionally altered to allow for its insertion into a connector housing by deforming portions of the terminal inwardly to clear housing surfaces. The machine and method of the invention further embrace a second aspect wherein the terminals of the connector, after termination, are fully seated within the housing by a machine compression stroke, with the driving surface of the machine having an angular disposition which biases a carrier strip interconnecting all the terminals of the connector to buckle and bend in a way allowing its subsequent removal by breaking following complete loading of the terminals into the connector housing. The foregoing is achieved through simplified motor driven mechanisms capable of repeated utilization with minimum adjustment.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1a is a perspective view of a four position connector including a housing and four terminals partially preloaded therein.
FIG. 1b is a view similar to that of FIG. 1a with the terminals terminated to conductor wires and completely inserted within the connector housing.
FIG. 1c is an enlarged perspective view of one of the terminals as shown in FIGS. 1a and 1b terminated to an electrical wire conductor.
FIG. 2 is a front elevational view of the machine of the invention showing the general arrangement of motor, drives loading guide track and details useful in understanding the invention.
FIG. 3 is a front elevational view of the feed slide mechanism of the machine showing details relative to the pawl feed finger which effects indexing of connector housings.
FIG. 4 is a top plan view, partially sectioned, of the feed slide mechanism shown in FIG. 3.
FIG. 5 is a perspective view of the detent and pawl feed finger mechanism of the invention somewhat enlarged from that shown in FIGS. 3 and 4.
FIG. 6 is a view of the machine of the invention taken from the right side thereof relative to the view shown in FIG. 2.
FIG. 7 is a view of the machine of the invention taken from the left side thereof relative to the view shown in FIG. 2.
FIG. 8a is a part plan view looking down on the connector housing loading and bending mechanism in an initial position prior to terminal loading into a housing, this mechanism being shown to the left in FIG. 2.
FIG. 8b is a showing of the mechanism of FIG. 8a following terminal loading.
FIG. 9a is a side and elevational view in partial section of the mechanism shown in FIG. 8a.
FIG. 9b is a side elevation and partially sectioned view of the mechanism of FIG. 8b.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1a, a connector 10 of a type chosen to illustrate the invention has four positions to accommodate four in-line electrical terminals. It is to be understood that the connector 10 is a member of a family which has terminal positions ranging from 2 up to as many as 30 which are generally furnished in multiples of two, although insofar as the invention is concerned, can have odd numbers of positions as well. The connector 10 includes a housing 12 molded of plastic dielectric material, a wide variety of such materials of suitable electrical grade being commercially available in the form of "engineering" plastics. Connector 10 further includes terminals 13 which fit within the housing 12 following termination to electrical wire conductors as is depicted in FIG. 1b.
The connector housing 12 is accordingly supplied with a series of spaced apertures 14 and 15 in the top wall thereof, two distinct rows of apertures which serve a terminal latching function to be hereinafter described. The top wall apertures shown toward the front of the connector have vertical surfaces that are to provide an indexing function. The front face of the connector housing 12 contains a series of four apertures not shown, in communication with respective passages 16 in housing 1 in FIG. 1a. The terminals 13 for connector 10 are, in the embodiment of FIG. 1a, stamped and formed of conductive material having spring qualities such as phosphor bronze of an appropriate hardness to include a variety of details. Reference is made to U.S. Pat. No. 4,435,035 for a teaching as to terminals of the type of those shown in this application.
These terminals are as shown in FIG. 1a connected to carrier strips 26 and 27, overlapped to place the terminals which extend therefrom in an alternating arrangement to provide a constant spacing of terminals much closer together than the flat geometries would otherwise allow. The carrier strips include a series of projections 28 and a series of apertures 30 which are aligned in the top and bottom portions of the carrier strips and serve as indexing holes for feeding the terminals during an initial stamping and forming thereof and subsequently, for feeding the terminals in plating and assembly operations. Each of the terminals 13 is connected to the carrier strip by a bridging section 29 relative to the upper carrier strip 26 and each of these sections has a score S which permits a ready bending of the section and relatively clean break following bending for removal of the carrier strips after termination and loading, such removal leaving the connector as it appears in FIG. 1b.
Each of the terminals includes a wire strain relief portion comprised of thin and crimpable tabs 32 in FIG. 1a and a termination portion in the form of an insulation displacement portion 34 having terminating slots at each end thereof which penetrate the insulation of conductive wires and provide a reliable, permanent electrical connection between terminals 13 and the wires. Ahead of the portion 34 are further tabs 38 and 39 formed of the terminal stock. The tab 38 which is vertically upstanding and is made to be relatively deformable as by crimping, serves to bear against the end edge of the rear of the connector housing 12 as shown in FIG. 1a to preclude movement of the terminal further into the housing and forms part of a latching mechanism, so as to maintain the terminal array in the housing. Tab 38 subsequently is folded over at right angles to the longitudinal axis of the terminal while tab 39 acts as a wire stop precluding the wire or portions thereof from projecting forwardly into the contact spring elements of the terminal as is shown in FIG. 1c. FIG. 1c best reveals projections 40 which are dimensioned relative to the base of the box-like terminal structure to secure the terminal within the interior of the passage 16 of housing 12 against rotation or up and down movement, the width of the box-like structure working similarly to preclude the terminal from sideways movement within the passage of the housing. Just forward of projections 40 on the top of terminal 13 is a spring element 42 having detent 44 biased upwardly and dimensioned to latch into the apertures 14 when the terminals are positioned as shown in FIG. 1a and further, into apertures 16 when the terminals are fully inserted as is depicted in FIG. 1b. As can be appreciated, with the terminal strip inserted and the detents 44 in place in the passage 16, the tabs 38 preclude forward movement of the terminal strip to the housing and the detents preclude rearward movement to thus latch terminal strip relative to the housing for handling of the assembly of housings and terminal strips prior to use.
Included in the box-like structure of terminal 13 in the forward end, is a contact spring 46 struck from the sides of the contact terminal material which mate with posts inserted within the terminal to effect an interconnection to the conductive wires W in FIG. 1c, a typical post being shown as P in 1c prior to such interconnection.
Referring now back to FIG. 1b, the center-to-center spacing of passages 16 of the housing 12 and thus of the terminals as mounted therein is the same distance D as shown in FIG. 1b. This spacing is held for common points along the width of the housing, except relative to the leading edge and trailing edge 17 and 23 in FIG. 1a. This reference is made relative to the movement of the connector in accordance with the method and machinery hereinafter to be described, such movement being shown by the arrow in FIG. 1a. As can be discerned, the leading top edge 17 includes a housing dimension LE and the trailing top edge 17 includes a dimension TE, both of these dimensions being different from similar top surfaces of the housing in between such apertures 14 and 15. In an exemplary reference to dimensions LE and TE in an actual connector considering that the center-to-center spacing D was on the order of 100 units, the dimension LE was 10 units and the dimension TE was 40 units. This dimensioning is necessary to provide adequate housing material thickness, while at the same time permitting molding techniques for manufacture of the housings. As can be appreciated, this variation in dimension means that indexing the connector assembly presents varying dimensions to any sort of feed mechanism utilizing the detent apertures 15. Furthermore, when it is realized that the housings such as 12 may come in positions ranging from 2 to 30, with the positions varying from connector to connector during the same processing operation such as a stream of connectors having 2, 4, 2, 6, 8, 10 or some other multiple of positions, the background problem heretofore set forth can perhaps better be appreciated. Additionally, the design problem required that housings like 12 having at least two stylings be accommodated, the principle difference being the length of the housing 12 or the characterization of projections above or beneath of the housings utilized for interconnecting with other housings or latching the housings to other connectors.
In summary, a family of connectors having two styles of housings and multiple positions is contemplated, wherein the housings contain terminals attached to the terminal carrier strips in a partially assembled condition. The assembly of housing and terminals is fed through the machine of the invention to be loaded with conductor wires placed into the terminals and terminated thereto, with certain portions of the terminals deformed and the terminals and carrier strips displaced relative to the housings to insert such terminals within the housings, with the carrier strips being bent by the machine to allow ease of removal of the carrier strips following termination and insertion. Further, the terminals latch themselves into the housings during insertion and all of these functions are carried out with the terminals being maintained on centers to tolerances as stamped rather than in some other loose piece or form which has a much wider tolerance.
FIG. 2 shows the machine 60 as viewed from the front face with the view depicting the machine tilted to make the mechanisms oriented to travel in the plane of the paper. Figure 6 should now be referred to to understand that in fact the machine is carried at an angle of roughly 60 degrees relative to the horizontal in terms of such motions. In FIGS. 2 and 6, control buttons 62 can be seen for the two distinct machine halves, the buttons 62 operating functions of the right-hand portion of the machine which is the indexing and terminating and crimping portion, and the button 64 operating in part the functions of the left-hand portion of machine 60 which serves to fully load the terminals within housings and effect the bending of the carrier strip as heretofore described. The two portions of the machine could indeed be separate machines, but that would necessitate that the housings be carried from one machine to the next, reloaded and so on.
Referring again to FIGS. 2 and 6, a guide track 66 is shown which accommodates the connector terminal assemblies in a form as depicted in FIG. 1a, the track 66 having interior dimensions which hold the housings therein for displacement from right to left. The length of track shown in FIG. 2 is intended to accommodate a supply of housings such as twenty or thirty which may be arranged in a sequence of positions in accordance with production needs or some subsequent sequence of processing. Alternatively, and not shown, cartridges containing housings having preassembled terminals therein may be provided and fitted to track 66 or even further, alternatively reels of such product may be provided and arranged on track 66.
As is further shown in FIG. 2 toward the center thereof, a plate 67 is fixed against movement to the frame of the machine and includes in the lower portion a wire guide and slot structure 69 which permits an operator to insert a wire to be terminated in an aligned position relative to an indexed connector and terminating and crimping tooling driven up and down in machine 60. This tooling is shown in phantom behind plate 67. Machine 60 may be seen to have a frame including sidewalls 68 to which are bolted a number of plates including 70 in turn carrying the driving and driven mechanisms of the machine. As can be seen in FIGS. 2 and 6, the plate 70 has mounted thereon a motor 72, which is typically an electric motor arranged to drive a pulley 74 in turn, driving a belt 76, a further pulley 78 locked to a shaft 80 through appropriate gear reduction which carries cam driver 82 having an eccentric cam 84 mounted thereon. Cam 84 is fitted within a slot 85 within sliding block 86 which is secured to a ram structure 88. As the motor 72 is driven to rotate, the drive rotates with cam 84 moving within slot 85 as cam 84 drives the block 86 downwardly and upwardly along the axis shown by the arrow in FIGS. 2 and 6. Referring to FIG. 6, the block 86 is suitably keyed as at 87 to the ram drive structure 88 for ease of assembly, and the ram drive is connected to two rams 90 and 92, suitably supported for sliding movement within the structure 93 secured to the frame of the machine.
As can be best seen in FIG. 2, the ram 92 includes a cam element 94 positioned to engage and displace a cam follower 98 to the left. This follower 98 is mounted in a slide feed assembly 100 more particularly shown in FIG. 4. The slide feed assembly 100 is fixed within the right-hand lower portion of the machine 60 as can be discerned by comparing FIGS. 3 and 4 with FIG. 2. The feed slide member 103 can be particularly viewed in FIG. 3. It is connected to cam follower 98 by a screw 99 to be driven back and forth by such cam follower, a compression spring element 102 serving to provide the return movement, the feed slide member 103 is fixed against vertical movement within the assembly 100, the limits of horizontal movement being established by the cam follower and slide feed adjustment screw 140 shown in FIGS. 2 and 4. Block 104 is the mounting for the slide feed as shown in FIG. 4 and wire guide 69 is mounted in block 93 as also shown in FIG. 4. The ram 90 which contains the terminal stuffing termination and crimping tooling can be seen in FIG. 4, along with a portion of the rear ram 92, along with the rear ram 92. Toward the center of the slide feed assembly 100 is a detent element 106 which is spring loaded by spring 108 downwardly to engage the apertures 15 in housing 12 heretofore discussed relative to FIGS. 1a and 1b. FIG. 5 shows the nose 107 of the detent element 106 as beveled and the detent element is confined for vertical movement in the block 104 of the slide feed assembly 100.
Trapped behind the slide feed member 103 is a pawl structure shown as slide feed finger 120 in FIGS. 4 and 5. The finger 120 is pivotally mounted to the slide feed member 103 by a screw 142 having an eccentric fitted into an aperture 112 of the feed finger 120 as shown in FIGS. 4 and 5. By rotation of the screw 142, the feed finger 120 may be adjusted toward or away from the detent element 106. A spring 132 shown in FIGS. 3 and 4 biases the feed finger 120 downwardly in the position shown in FIG. 3.
FIG. 5 shows an enlarged view of the feed finger 120 in association with the detent element 106 and the relationship of the feed finger 120, the spring 132 for feed finger 120 and spring 108 for the detent element 106. As can be seen particularly in FIG. 5, the feed finger 120 has a lower projection 124 which ends in a series of step surfaces 126, 128, 130 and 132, which variously engage surfaces on the housings indexed by the feed finger 120 in its horizontal movement. The lower projection 124 of the feed finger 120 is relieved as at 134 to allow an internesting of the detent element 106 so that it lines up with the step surfaces 126-132.
Referring now to the operation of the apparatus of the invention, a series of connectors are loaded into track 66 and moved to the left manually until the leading edge, referencing FIG. 1aof the connector housing, strikes the tapered end of detent element 106, the assembly being positioned in the guide track so that the end of the detent element is aligned with the forward apertures 15 of housing 12. At this point in time, the ram 92 associated with the feed finger 120 will be in the upward position, slide feed member 103 and feed finger 120 will be biased to the right. In accordance with procedures for the apparatus, the operator will cycle the apparatus to force the housing to the left in the track 66 until the detent element 106 rides over the edge LE and nests within the first aperture 15, being forced downwardly by spring 108 to lock the housing in a proper position. At this point in time, the operator will insert an unstripped lead wire through wire guide 69 so that it overlies the first terminal 13 of the connector, that terminal associated with first aperture 15. With the lead so positioned, the motor 72 may be cycled through the energization of an appropriate circuit such as a solenoid to drive the rams 90 and 92 downwardly. Ram 90 carries at the end thereof, tooling of a configuration to deform the terminal as shown in FIG. 1c. This tooling includes a crimping die shaped to crimp the tab 38 downwardly from the position shown in FIG. 1a to the position shown in FIG. 1c. This die further includes a stuffer which will stuff the wire into the insulation displacement portion 34 heretofore discussed, to terminate the wire and crimp the tabs 32 around the wire insulation to provide strain relief. Interiorly of the crimping tool area is the tab 39 lined up with projection 38 in a vertical sense which causes the end of the wire to rest against 39 following termination and crimping. The ram returns to the up position at this part of the cycle with the slide feed member 103 returning to the right.
In accordance with this invention, the displacement of the feed finger 120 is relatively fixed for each machine cycle. In the description here given, surface 128 of the feed finger would find surface B of the second aperture 15 and be biased into engagement therewith by the spring element 132 which pushes the feed finger downwardly.
Referring back to the cycle just described, as the ram 92 descends during the cycle just described actuating the cam element 94, the tapered surface 96 thereof drives the cam follower 98 to the left thereby driving the feed slide member 103 to the left and in turn, driving the feed finger 120 to the left with the surface 128 driving the housing 12 to the left, detent element 106 being biased upwardly to ride along the housing surface until the end of the machine stroke, whereupon the detent element is lodged within an appropriate aperture 15. At this time the ram 92 continues on its downward travel with no further displacement of the cam follower 98 which is riding upon the flat area of the cam element 94. Ram 90, the forward ram, carrying the termination and crimping tooling, progresses as described downwardly to stuff the conductor wire into the termination portion of the next terminal, deform elements 32 and 38 to effect a termination and crimping action, with the ram then returning upwardly as cam driver 82 rotates and as the eccentric cam 84 cams block 86 upwardly. At this point in the cycle, the feed finger 120 will be again positioned to the right driven by the feed slide member 103, itself driven by the compression spring 102 to the end of its travel against the adjustment post 140. The end of the feed finger 120 will be biased downwardly by the spring 132 so that one of the surfaces 126-132 will engage an appropriate surface of the housing, in this case, a surface one unit away from the previous location which in the present instance would be surface C of an aperture 15. This operation would then continue until the housing was completely terminated and until the feed finger, one of its surfaces, reach the trailing edge or surface E should there be no connector following the connector just completed. Alternatively, the under surface 126 of the feed finger will engage surface A of the next connector proximate to the leading edge LE of the next connector. In this way, the feed finger arrangement of the apparatus of the invention accommodates the varying dimensions associated with feeding housings which have different numbers of positions and different indexing surfaces thereon. Relative to the family of connectors of the type shown in FIGS. 1a-1c, the two surfaces 126 and 128 will suffice. The remaining surfaces 130 and 132 are used for a similar type of connector but one having different surfaces A-E than those represented, in dimensional terms.
With the last terminal terminated and crimped, the connector housing will be free of detent element 106 and the operator will then, utilizing the crimped conductor wires, slide the terminated assembly along the track 66 to the next station or the left-handed portion as viewed in FIG. 2 of the machine 60 of the invention. As can be discerned from FIG. 2, the track 66 is accommodated by a fixed guide portion 97 which is relatively broad or wide and does not require the assembly to be precisely positioned. Again, referencing FIG. 2, the assembly can be positioned in the general vicinity of the center line of the guide 97 or as more particularly shown in FIGS. 8a and 8b, looking down upon the assembly, or of FIG. 9a looking in from the left of the assembly referencing FIG. 2.
In FIG. 7, the left-handed portion of the apparatus 60 may be seen to include a motor 150 suitably mounted to the frame of the assembly by bolts 151. Motor 150 drives a pulley 152, a belt 153 which in turn drives a pulley 154 of gear reduction drive 156, which is secured as by a bracket 158 as shown in FIG. 7. The shaft 159 which is an output from gear reduction drive 156, carries an eccentric assembly 160 having an eccentric cam 162 thereon. The lower portion of the apparatus is fixed to the frame element 170 including the guide track portion 97 as shown in FIGS. 2, 8a and 8b. Upon this lower portion, there is provided a movable assembly which includes a cross-plate 172 carrying a cam block 174 having a cam surface 176 thereon and adapted to be driven in movement toward the guide track assembly 97. There is provided a plate 178 as shown in FIGS. 8a and 9a which has a projection 179 which limits the movement of the connector housing in a vertical sense. As viewed in FIG. 9a, the lower movable portion of the assembly includes a block element 180 which is driven to the left as shown in FIG. 9a by a set of compression springs 182 captured between the right edge of 180 and a guide pin 183 secured to the fixed guide support structure 184. This fixed portion includes a block spacer 186 carrying the outboard portion of the feed track including particularly a member 188 as shown in FIG. 9a which engages the end of the carrier strips 26 and 27, referencing FIG. 1a. A cap plate 190 covers the carrier strip at this point to prevent its upward vertical movement. The cap plate 190 includes the beveled surface 191 over which the wires W are laid for sliding movement therealong when the connector is in the left-handed portion of the apparatus.
To the left of the connector as shown in FIG. 9a is a plate 192 which has a projection including a projection 196 which catches the forward end of the connector housing 12 and confines such against movement inwardly of the apparatus. Plate 192 is mounted to the movable block 180, and driven by the cam 162 disposed on cam block 174 as shown in FIG. 8a.
Viewing now the operation of the apparatus in the terminal insertion and carrier strip bending function, reference is made to FIGS. 8a, 8b, and 9a and 9b. In FIGS. 8a and 9a, the connector is shown in an initial position as placed by an operator following termination with the conductor wires guided over plate 190 as shown in FIG. 8a and with the motor and drive mechanisms in an initial precycle condition as referenced by the position of cam 162 as shown in FIGS. 8a and 9a. Upon the initiation of the cycle as by a foot switch interconnected to the motor through a solenoid or in the event of the use of a stepping motor through an electronic power supply, assembly 160 is driven to rotate, carrying the eccentric cam 162 around to engage the cam surface 176, driving such to the right as shown in FIG. 9b or downwardly as shown in FIG. 8b against the compression of springs 182. As this occurs, the ends of the carrier strip engage member 188 and the housing 12 is driven by projection 196 to the right as shown in FIG. 9a until the terminals are loaded with the detents 44 snapping into the apertures 15 associated with housing 12, referencing FIGS. 1a and 1b. The connector will now be in the condition shown in FIG. 1b with the terminals seated within the housing and latched therein. In accordance with the invention, however, movement continues in this cycle until the connector is in the position shown in FIG. 9b, so that a force is generated which buckles and bends the carrier strips downwardly at or around, the score lines S, previously described in reference to FIG. 1a. The cycle continues with the eccentric cam 162 rotated back to the initial position as shown in FIG. 8a and in FIG. 9a, with the operator then removing the connector having the carrier strip bent as shown in FIG. 9b. Thereafter, the operator can inspect the assembly and remove the carrier strip merely by bending it more toward 90 degrees relative to the insertion axis of the connector.
According to the foregoing, multiple connectors of different styles and different numbers of positions may be accommodated without essential changes in the apparatus, one set-up is accomplished. The right portion of machine 60 and the left portion will operate to allow termination, assure indexing and loading of terminals and bending of the carrier strips of connectors of different dimensions. | The present invention relates to a method through which a machine is enabled to feed a preloaded electrical connector (10) on appropriate spacings to allow the termination of individual wires (W) in terminals (13) in the connector through a novel indexing feed finger (120) which is capable of engaging surfaces (A-E) on the connector which are different relative to a constant indexing stroke. The indexing finger includes surfaces (126-132) capable of handling more than one set of dimensions of more than one style of connector without adjustment. The invention further includes a mechanism (180) for bending a scored portion of terminals to effect a later removal of the terminal carrier strips. | 8 |
This application is a continuation of U.S. application Ser. No. 08/580,764, filed Dec. 29, 1995 now U.S. Pat. No. 5,734,734.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to the field of loudspeakers, and in particular, to a voice coil adaptor ring for mating the cone and spider for increased strength and efficiency.
2. Description of the Prior Art
With reference to FIG. 1, a conventional loudspeaker 20 generally comprises a support frame 22, a cone 24, a dust cap 26 bridging across the cone, a suspension system, a voice coil 40, a voice coil bobbin/former 43, and a vented pole piece 41. The voice coil 40 is wound about the voice coil former 43 such that an annular magnetic gap is defined between a top plate 37 and the magnet and the voice coil 40. The magnetic circuit linearly cycles or displaces the voice coil former 43 in this gap. In the conventional speaker, the cone shaped diaphragm (cone 24) is attached to the voice coil former above the coil 40 at its lower end and to the frame at its upper end. A suspension system comprising two elements connects to the frame and upper end of the cone, and to the frame and voice coil former, respectively.
The suspension system of the loudspeaker normally comprises two elements, the surround 28 (upper or outer suspension) and the spider 38 (lower or inner suspension). The surround 28 is a mechanical device which holds the outer edge of the diaphragm/cone of the loudspeaker and is often referred to as a "roll." Typically, the surround comprises a single, large, semi-circular corrugation constructed from either rubber, compressed foam rubber, or some similarly treated fabric. Surrounds may also be constructed from several other materials including corrugated cloth, paper, plastic, etc. One purpose of the surround is to help keep the cone 24 centered and to provide a portion of the restoring force that keeps voice coil in the gap defined between the pole piece and the top plate of the loudspeaker. The surround also provides a damped termination for the edge of the cone. A choice of thickness and material type for surround construction can greatly alter the response of the loudspeaker.
A spider 38 is commonly constructed from treated corrugated fabric. The spider 38 comprises a lower/inner suspension member that helps to keep the voice coil concentric to the pole piece. A portion of the restoring force that maintains the voice coil within the gap is also provided by the spider. Thus, the stiffness of the spider can greatly affect the loudspeaker's resonance. The spider also provides a barrier for keeping foreign particles away from the gap area.
In addition to controlling the linear motion of the cone, the surround, like the spider, acts as a major centering force for the loudspeaker's voice coil. The voice coil generally comprises a winding concentrically supported by a cylindrical voice coil former. The centering force provided by the roll and spider prevents the voice coil and former from rocking and rubbing against the pole piece or top plate. Rocking is undesirable because it can cause audible noise and/or damage to the driver.
Often a loudspeaker design can be best optimized by utilizing a voice coil with a smaller diameter. However, the smaller voice coil setup creates certain problems, especially when designing loudspeakers for low frequency reproduction. Thus, for larger diameter loudspeakers (typically 10 inches and above), small voice coil systems are not common. Accordingly, there are few, if any, existing cones tooled for the smaller diameter coil former. To incorporate a small voice coil system, the cone must be customized, adapted or re-tooled.
One disadvantage of mating a cone directly to a smaller voice coil is that a relatively small adhesive joint is made. Since the voice coil's diameter is much smaller, the gluing circumference is drastically reduced. Therefore, the designer must be concerned with the possibility of mechanical failures since the stress distribution around the glue joint is high. Because the spider attaches at this critical junction as well, spider joint stress also increases, introducing yet another possible failure mode.
Another problem associated with smaller voice coils occurs in the use of pole vents. Pole vents comprise holes bored directly through the pole piece within the motor structure. These vents are used to relieve air pressure that builds up beneath the dust cap. Without a pole vent, audible noise can be introduced as the trapped air tries to escape during large cone excursions. However, when using a small diameter voice coil, the amount of metal in the pole piece is very limited. This amount of steel can only support limited amount of magnetic flux. Consequently, using a pole piece with large amounts of metal removed for pole vents can radically alter the performance of the magnetic circuit.
A vented pole piece further affects the thermal behavior of the speaker. The steel contained in the pole piece provides an effective thermal sink for the voice coil. Machining a pole vent in the pole piece increases thermal resistance of the sink, lowering the power handling capability of the loudspeaker.
The mechanical integrity of the spider is also compromised when using a small voice coil. Spiders are typically made from resin treated cloth materials. When the inner diameter of the spider gets smaller, fewer strands of material intersect the cutout. Since the glue joint lies on this small circumference, very little spider material is captured. This places the spider material under greater stress than normal. This high-stress condition could cause the spider itself to fatigue prematurely. Since the spider is typically called on to center the moving assembly and limit cone motion at the extremes of excursion, a compromised spider could cause a catastrophic failure.
Rocking resistance is also compromised when using a smaller inner diameter voice coil. Rocking in a loudspeaker describes the moving assembly rotating in the vertical plane about a point located along its axis of motion. As a spider's inner diameter gets larger, the material along the inner diameter is required to deflect more when the moving assembly rotates a given amount (as during rocking). Consequently, a spider with a larger inner diameter will be more resistant to rocking because more energy is required to invoke a given angular change. It follows that using a small voice coil, and hence a small inner diameter spider, makes a given loudspeaker more susceptible to rocking related problems.
The smaller voice coil system further affects the cone's structural integrity. As a voice coil gets smaller, the cone angle increases (using a vertical axis as a reference), causing the cone to become flatter. As the cone begins to flatten, its mechanical strength drops. Increasing the cone angle increases the likelihood of audible degradation due to cone flexure. Normally, the only option available for preventing cone flexure is to increase the cone thickness and/or increase the cone depth. This decreases the cone angle and makes the cone wall more vertical. These solutions, however, are not desirable since increasing the cone depth requires a larger frame depth and using a thicker cone adds weight to the moving structure. Moreover, thicker cones and deeper frames require special tooling and make the speaker's mounting depth unattractive for certain applications.
Several loudspeaker designs are contemplated in the background art for improving speaker performance, stabilizing the speaker cone/diaphragm, and/or simplifying the manufacturing process. However, none of these references solve the above-noted problems. For example, Mitobe (U.S. Pat. No. 5,111,510) discloses a speaker and manufacturing method therefor including a diaphragm integrally combined with a first frame piece and a driver unit integrally combined with a second frame piece. Saiki et al. (U.S. Pat. No. 5,371,805) discloses a speaker and speaker system employing the same, comprising a diaphragm secured to a first periphery of an edge member and a frame secured to a second periphery of the edge member. Scholz (U.S. Pat. No. 5,323,469) discloses a conical loudspeaker having a conical stabilizing element joined between an underside of a speaker membrane and an outside surface of a speaker moving coil carrier. Kreitmeier (U.S. Pat. No. 5,424,496) discloses an electromagnetic converter comprising an internal magnet system, a moving coil and tubular segment. Kreitmeier (U.S. Pat. No. 4,764,968) discloses a disk-like diaphragm made from a conical plastic film and provided with vacuum formed support members which extend up to the disk-like radiating layer. Finally, Kobayashi (U.S. Pat. No. 4,118,605) discloses a coil mount structure comprising a cylindrical member, around one end portion of which a diaphragm edge is fixed, an inner peripheral edge portion where a damper is removably fixed, and an opposite end portion around which a coil is provided. Kobayashi, however, does not provide any structure for ventilating air pressure from beneath the dust cap or a structure for creating a secure joint between the diaphragm/cone, spider, and/or voice coil. The present invention, by way of contrast, is directed to an adaptor ring, the structure of which facilitates a stronger adhesive joint between the cone, spider, and voice coil bobbin or former, and a means for venting air pressure buildup.
The above-noted background art neither solves or addresses the problems contemplated by the present invention. Accordingly, there remains a need for a loudspeaker capable of providing improved structural joints between the speaker cone, spider, and voice coil former, allowing the use of smaller voice coil systems and providing ventilation in the speaker without forfeiting performance. The instant invention addresses the needs in the art by providing a voice coil adaptor ring that provides increased stability to the speaker cone, spider, and voice coil former, and that facilitates the reliable use of smaller voice coils in loudspeaker designs, including low frequency speakers. The instant invention also addresses the need for improved ventilation.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a structure that facilitates the secure attachment of a cone edge, spider, and voice coil for improved loud speaker performance.
Another object of the invention to provide a voice coil adaptor ring that allows for a stronger joint between the cone/diaphragm, spider/lower suspension and voice coil.
It is also an object of the invention to provide a voice coil adaptor ring that makes it possible to use relatively small voice coils in low frequency speakers.
It is a further object of the invention to provide a voice coil adaptor ring that eliminates the need for machining pole vents in the pole pieces of loud speakers.
It is an additional object of the invention to provide a voice coil adaptor ring that facilitates use of a larger inner diameter spider that is more resistant to rocking.
It is another object of the invention to provide a voice coil adaptor ring that makes it possible to reduce the cone angle for a given voice coil size to strengthen the cone.
It is still an additional object of the invention to provide a voice coil adaptor ring that provides a structure that eliminates the need for adhering the spider and cone to the voice coil former.
It is still a further object of the invention to provide a structure that allows the cone to mechanically lock and secure the spider suspension.
It is yet another object of the instant invention to reduce the number of failure points in a loudspeaker and the probability of loud speaker failure.
Another object of the instant invention is to reduce stress in the joints securing the spider and cone.
A further object of the instant invention is to provide a voice coil adaptor ring that allows the cone to be attached further out from the voice coil former to increase the vertical angle of the cone and hence the cone's strength.
According to these and other objects, the present invention comprises a voice coil adaptor ring and a loudspeaker with a moving coil that incorporates the adaptor ring. The loudspeaker comprises a cone, a dust cap, a frame supporting the cone's upper end, a voice coil former, a voice coil wound around the former, the adaptor ring mounted to the former, a lower suspension (spider) connected at one end to the frame and at the other end to the adaptor ring for centering the voice coil system, and a magnetic circuit including at least one magnet, front plate, a back plate and a pole piece. The adaptor ring comprises a substantially cylindrical sleeve adapted for mating over the voice coil former and for securing and attaching the speaker cone/diaphragm and spider suspension. The adaptor ring of the instant invention defines at least one ledge around its lower peripheral edge having sufficient surface area for receiving, supporting and adhering the speaker cone and spider. Accordingly, the ledge is also referenced as a spider plateau since it provides a horizontal platform for supporting the spider. The spider plateau stabilizes and increases the structural integrity of the cone for minimizing deflection and providing an overall improved performance and strength. This plateau/edge provides a larger surface area for adhering the spider which is superior to gluing it directly to the vertical wall of the voice coil former, as shown in U.S. Pat. No. 4,764,968. By providing a substantially horizontal plateau for securing the spider suspension, adhesives may be applied to both the upper and lower sides of the spider for increasing the adhesive contact area. The extra adhesive contact area defined by the plateau provide for a strengthened spider attachment so as to greatly reduce the possibility of failure.
The plateau also benefits the cone in that it provides a mechanical stop for receiving the cone's lower edge and adhering it to the adaptor. This enhances the joint between the cone and adaptor for increased reliability and reduced likelihood of failure. If the cone is attached to the top of the spider, the spider can be completely locked and secured in place so as to virtually eliminate this joint as a possible failure point in the loudspeaker. A substantial decrease in stress on the glue joints is realized by the structure and method of the instant invention. In short, there is better stress distribution across the joint and increased stability provided by the spider plateau.
The adaptor ring of the instant invention further comprises venting passages vertically bored through the wall of the adaptor ring from top to bottom for releasing air pressure build up in the volume defined by the cap and/or cone. These venting passages of the instant invention eliminate the need for providing a pole vent in the pole piece. Eliminating the pole vent reduces manufacturing time and costs. A solid pole piece also offers an increase in magnetic circuit efficiency as well as a less resistant thermal path for heat transfer from the voice coil. An improvement in the heat transfer from the voice coil increases the power rating of the driver making the speaker more reliable. It has been determined that when a fairly porous spider is paired with the venting passages, air may exit noiselessly from the cone volume.
The adaptor ring of the instant invention defines an inner diameter adapted to receive the voice coil former for mounting the adaptor ring on the speaker. Accordingly, the cylinder is dimensioned to correspond to the voice coil former. An inner glue flange may be defined along the inner wall and floor of the adaptor ring. When the adaptor ring is installed over the voice coil former an inherent gap remains between the interior wall of the ring and the voice coil former. This gap is filled with glue to adhere the adaptor ring to the voice coil former. In the alternative, the voice coil former may have a stop projecting from the former for locking the adaptor ring in place.
The spider plateau of the adaptor ring may also include at least one wire channel, or slots in the inner glue flange along its circumferential edge to form channels when the adaptor is mounted to the former, for running speaker wires, such as the lead out wire. In the alternative, the wire may be passed through one of the venting passages. The ring may also include a textured or ribbed surface for increased surface tension when applying adhesives.
While the instant invention is described with reference to loudspeakers having small voice coils, the voice coil adaptor ring may be incorporated with other loudspeakers for improved performance and strength.
The invention is described in detail below with reference to the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a prior art loudspeaker;
FIG. 1A is an illustration of the cone angle increase when incorporating the instant invention;
FIG. 2 is a top perspective view of the preferred embodiment of the voice coil adaptor of the instant invention;
FIG. 3 is an bottom perspective view of the voice coil adaptor of the instant invention;
FIG. 4 is a cross-sectional view of the preferred embodiment of the loudspeaker and voice coil adaptor ring of the instant invention, as installed in the loudspeaker;
FIG. 5 is a top planar view of the voice coil adaptor ring of the instant invention;
FIG. 6 is a cross-sectional view of the voice coil adaptor ring of the instant invention taken along line 6--6 of FIG. 5;
FIG. 7 is a cross-sectional view of an embodiment of the voice coil adaptor ring taken along line 7--7 of FIG. 5;
FIG. 8 is a cross-sectional view of another embodiment of the loudspeaker of the instant invention with a partial cutout in the voice coil former to illustrate grooves on the inner surface of the voice coil former when the former and adapter ring assembly are manufactured from a conductive material; and
FIG. 9 is a cross-sectional view of another embodiment of the adaptor ring of the instant invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the drawings, FIGS. 2-9, depict the preferred embodiment of the voice coil adaptor ring 51 and loudspeaker system 50 incorporating the adaptor ring 51 in accord with the preferred embodiment of the instant invention. The loudspeaker 50 of the instant invention incorporates the voice coil adaptor ring 51 and comprises a cone-shaped diaphragm 24' (cone), a frame 22' supporting the upper end of the cone 24', a voice coil 40' wound around a voice coil former 43', the voice coil adaptor ring 51 mounted over the former 43', an upper suspension 28', a spider 38' and a magnetic circuit. The spider 38' is attached and adhered to the adaptor ring 51 to provide a centering force for the former 43' and voice coil 40'. The magnetic circuit comprises at least one magnet 35', a pole piece 41', a front plate 37' and a back plate 33'. A magnetic gap exists between the top plate 37' and the pole piece 41. Together, the adaptor ring 51 and spider suspension center the voice coil system and former in this gap.
The voice coil adaptor ring 51 comprises a sleeve having substantially cylindrical walls 52 adapted for snugly mating and conforming to the outer peripheral edges of the voice coil former 43'. With reference to FIG. 9, the adapter ring in the alternative may comprise other shapes, such as conical, without departing from the scope and spirit of the instant invention. As seen in FIG. 4, the adaptor ring S defines a first inner diameter Dl which corresponds to the diameter/dimensions of the voice coil former 43'. The first inner diameter D1 of the adaptor ring 51 may be defined by an inner glue flange 58. A second inner diameter D2, larger than the first, is defined by the exterior of wall 52a. Thus, a gap exists between the interior wall 52a and the exterior wall of voice coil former 43' when the ring 51 is installed. This gap is filled with epoxy 60 to secure the adaptor ring 51 to the voice coil former 43,. Since the ring 51 inner diameter mounts over the voice coil former 43', an inherent gap is still present for adhesives without the inner flange 58. Adhesive adheres the ring 51 to the former 43'.
In the alternative, the former 43' may be manufactured with a projecting shelf on which the adaptor ring would sit and lock in place. In this alternative embodiment, the inner glue flange 58 would define grooves 59 which would interlock with the projecting shelf where the adaptor ring is rotated, locking it in place.
The adaptor ring 51 further comprises venting passages 56 which are bored vertically through the cylindrical walls 52 to provide a complete passageway for venting air from the cone volume of the speaker. The cone volume is defined by the cone walls 24' and dust cap 26'. In a speaker with just a cone 24, the cone volume is defined by the cone 24. The venting passages 56 prevent pressure build up in this volume for improved sound quality.
With reference to FIGS. 6-7, a cross-section of the adaptor ring is shown to illustrate the venting passages 56 and the inner glue flange 58. The passages 56 are divided by partitions 57. The partitions 57 may be sloped, tapered, planar or otherwise. Selected partitions 57' may be sloped, as shown in FIG. 7, to reduce stress on lead out wires when they are run through the adaptor 51. Lead out wires are typically fragile, so bending the wires at right angles would increase the risk of fractures. Referring to FIGS. 2-7, the adapter ring 51 includes a means for running lead out wires. This wire running means preferably comprises slots 59 defined at selected locations around the inner peripheral edge of the inner glue flange 58 so that wire running channels are formed when the adapter ring 51 is mounted to the voice coil former 43'. The slots 59 should be in alignment with the sloped partitions 57' so that lead out wires may be passed through the wire channels and over the sloped partitions. In the alternative, wire channels may be bored through the adapter ring walls 52, plateau 54 or inner glue flange 58. The adaptor ring 51 may be manufactured by any plastic, thermoplastic, polymer plastic, metal or other acceptable material. An injection molding process is preferred to make the ring 51. It should be noted, however, that any embodiment of the adapter ring may be manufactured integrally with the voice coil former 43', such that the adapter ring would be metallic. At least one wire channel 55 may also be provided by the ring 51 for running wires.
The venting passages 56 eliminate the need for a pole vent 42, as shown in FIG. 1. The conventional pole vent 42 is required in the background art to vent heat and air pressure build up in the cone volume, as defined by the dust cap 26 and the cone 24. The voice coil adaptor ring 51 of the instant invention eliminates the pole vent 42 by including venting passages 56 in the adaptor ring 51, as discussed above. The venting passages 56 comprise channels bored completely through the cylindrical wall 52 from the top end to the bottom end. Replacing the conventional pole vent 42 with the adaptor ring vent passages 56 saves machining in the pole piece structure 41 so as to reduce costs. A solid pole piece 41 also increases magnetic circuit efficiency and provides an improved thermal path for heat transfer from the voice coil. By allowing for improved heat transfer from the voice coil, the driver may be operated at a higher power rating.
With reference to FIGS. 2-8, the adaptor ring 51 of the instant invention preferably has cylindrical walls 52 that define at least one exterior spider plateau 54. The spider plateau 54 is preferably planar, or substantially horizontal, such that it provides a ledge for receiving and securing the spider/lower suspension 38' and the neck/lower edge of the speaker cone 24'. The spider plateau 54 preferably supports the inner edge of the spider 38' and provides enough surface area for applying adhesives between the spider 38' and the ledge 54 so as to firmly secure the spider in place. Adhesives may also be applied to the upper surface of the spider 38' for adhering the neck of the cone 24'. The instant invention is superior to the background art, whereby the ledge 54 of the adaptor ring 51 provides a more stable securing structure than the vertical surface of the voice coil former 43'. In addition, it provides a structure that enables the joining of the cone 22' and spider 38' for a stronger joint. Accordingly, attaching the spider 38' and cone 24' to the voice coil adaptor ring 51 along a larger circumferential planar surface provides more contact area for applying epoxy. This additional contact area alleviates stress on the glue joints via improved stress distribution for increased reliability. In the alternative, the surface of the spider plateau 54 and/or the entire adaptor ring 51, can be textured or ribbed to enhance adhesion. The adaptor ring 51 and spider plateau 54 also provide a mechanical stop for the cone's 24' lower edge providing a more reliable joint. Once the cone 24' is attached to the top of the spider 38', the spider 38' is completely locked in place. Consequently, the spider/cone/voice coil joint is virtually eliminated as a possible point of failure in the loudspeaker.
Referring to FIG. 4, the voice coil adaptor ring 51 provides extra coil attachment height allowing for a larger adhesive contact area, especially in small diameter voice coils. In addition, an inner glue flange 58 may aid in the gluing process by catching and holding the glue in contact with the coil former surface allowing a larger amount of adhesive to be used. This large joint provides a more favorable stress distribution around the coil former 43' making the attachment more reliable.
The voice coil adaptor 51 facilitates use of a corrugated spider 38' having a larger inner diameter in the area of its mid section. A spider with a large inner diameter is amenable with the instant invention because of the additional security provided by the voice coil adaptor ring 51 and spider plateau 54. That is, because more spider material is adjacent to the glue joint in a loudspeaker using the voice coil adaptor in 51, spider fatigue is less of a concern. As noted, a larger inner diameter spider 38' is more resistant to rocking that may incur in a loudspeaker. With the use of the adaptor ring 51, the acceptable spider material deflection is increased for a given degree of coil rotation making the spider more resistant to fatigue. The additional stability provided by the adaptor ring 51 and corrugated spider 38', make the speaker stronger and more reliable. The improved centering force allows for tightened tolerances in the magnetic gap as defined between the top plate 37, and pole piece for improved speaker performance. Maintaining a smaller magnetic gap increases the motor strength and enhances the thermal power handling of the loudspeaker.
The adaptor ring 51 moves the contact point of the lower cone edge outward. As a result, the cone angle is decreased, with reference to a vertical axis, for higher strength and rigidity. As a result, the cone 24' is not only more reliably stabilized, but may be manufactured from a thinner material reducing the cone's weight and audible coloration.
With reference to FIG. 8, the voice coil former 43' may have grooves 72 and 74 formed along the interior wall, preferably from top to bottom. The grooves 72 and 74 provide a means and structure for breaking any conductive loop in the former 43' that may result. These grooves 72, 73 may be especially necessary when the adaptor ring is formed integrally with the former 43' and the former-adaptor ring assembly is electrically conductive. An alternative embodiment of the adaptor ring is shown in FIG. 9, where the adaptor is conical in shape. The conical adapter 51' performs the same functions as the preferred adapter 51 and likewise comprises a spider plateau 54', a sloped wall 52', and vent passages 56'. A vertical stop 55 is also included in the alternative embodiment for receiving the cone and spider and facilitating an improved adhesion surface.
The instant invention has been shown and described herein in what is considered to be the most practical and preferred embodiment. It is recognized, however, that departures may be made therefrom within the scope of the invention and that obvious modifications will occur to a person skilled in the art. | A voice coil adaptor ring and loudspeaker system of the moving coil type including a cone diaphragm supported by a frame, a voice coil former for supporting a voice coil, and a lower suspension for securing and centering the voice coil former in a magnetic gap while it is displaced by a magnetic circuit. The voice coil adaptor ring is mounted over the voice coil former and comprises a substantially cylindrical sleeve having at least one ledge extending outward from said sleeve for supporting the cone and lower suspension and a plurality of venting passages in fluid communication with a cone volume defined by the cone for venting hot air from the cone volume. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of the filing date of U.S. Provisional Patent Application No. 60/598,245 filed Aug. 3, 2004, the disclosure of which is hereby incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to supporting cable line bundles or line routes and insulation materials such as insulation mats in aircraft. The present invention particularly relates to a mount for an aircraft for securing insulation material to a structure of the aircraft as well as an aircraft having a corresponding mount.
[0003] In aircraft, cable mounts are used to support and guide electrical line routes in different regions. Such mounts are tailored to the concrete connection conditions on the transversal carrier or frame (former), for example. For example, the mounts are tailored to the thickness of the web of the transversal carrier, to a hole diameter, and to a diameter of the electrical line routes.
SUMMARY OF THE INVENTION
[0004] According to one exemplary embodiment of the present invention, a mount for an aircraft is provided for securing insulation material to a structure of the aircraft. The insulation material has at least one recess having first dimensions. The mount of this exemplary embodiment comprises a first cable mount section and a second cable mount section. The first and the second cable mount sections are essentially made of a first material. This first material is plastic. For example, the first and the second cable mount sections may be manufactured through an injection molding method. The first and the second cable mount sections are connectable via a connecting element. The connecting element supports at least one plate-shaped element which has second dimensions that are larger than the first dimensions. Therefore, the plate-shaped element does not fit through the recess in the insulation material. The connecting element and the at least one plate-shaped element are made essentially of a second material, which is more heat-resistant or fire-resistant than the first material.
[0005] According to an embodiment of the invention, a mount is provided which, in addition to the function of supporting and guiding electrical line routes, pipes, etc., on ascending and descending routes, for example, may also support insulation mats which may be provided on structures of the aircraft.
[0006] Multipurpose mounts for supporting insulation material on structures in aircraft may, if they are implemented from plastic, melt in the event of great heat. However, the use of plastic may be desirable for saving weight. According to one exemplary embodiment of the present invention, a hanger is specified in which a plate-shaped element and a connecting element that are implemented from a very heat-resistant material are provided. The remainder of the hanger may be implemented from plastic. Under the effect of strong heat, the plastic may melt. An insulation mat may nonetheless be secured against falling down/detaching by the plate-shaped element, which is supported using the connecting element.
[0007] Therefore, a mount for aircraft may be specified, which may reliably prevent the insulation material from being able to slip over the plate-shaped element and therefore fall down in the event of great heat, under the effect of fire, for example. This may be achieved in that the plate-shaped element and the connecting element are made of a more heat-resistant or fire-resistant material, so that in case of fire, for example, the cable mount sections may melt, but slipping of the heat-resistant insulation material over the plate-shaped element is prevented, through which the structure of the aircraft and/or the passengers located in the aircraft are protected. A mount which is resistant to burning through and therefore prevents the loss of the insulation mat is specified according to an exemplary embodiment of the present invention.
[0008] According to a further exemplary embodiment of the present invention, the mount is implemented as a multipurpose mount and additionally has a cable receiving region for supporting cables. In this way, a multipurpose mount is specified which may both securely hold insulation material, even in case of fire, and is also suitable and usable for cable support and guiding.
[0009] According to a further exemplary embodiment of the present invention, the second material is a metal, because of which the connecting element and the plate-shaped element only melt later or even not at all, even in the event of very strong heat or in case of fire.
[0010] According to a further exemplary embodiment of the present invention, the plate-shaped element is a metal disk which is incorporated into the plastic of the first or second cable mount section. A notch may be provided for this purpose, for example, on which the metal disk, which may also be an open metal disk in the form of a split pin, may be placed.
[0011] According to a further exemplary embodiment of the present invention, the metal disk is implemented in one piece (may be integrally formed) with the first or second cable mount section. For example, the metal disk may be cast into the plastic material of the cable mount sections.
[0012] According to a further exemplary embodiment of the present invention, the connecting element is implemented using a metal screw and a metal nut. The metal nut is supported in one cable mount section, whereas the metal screw is supported in the other corresponding cable mount section. The plate-shaped element has a recess which has smaller dimensions than a head of the screw and the nut. When the mount is mounted, the plate-shaped element is positioned between the head of the screw and the nut. Therefore, in case of fire, even if all of the plastic of the cable mount section has melted, the insulation material, such as an insulation mat, may be supported and may be prevented from slipping off or falling down, through which protection of the interior is provided.
[0013] According to a further exemplary embodiment of the present invention, two plate-shaped elements are provided, which are positioned between the head of the metal screw and the nut when the cable mount sections are mounted. An insulation mat may thus be secured against falling down on two sides of a structure, for example.
[0014] Further exemplary embodiments of the present invention result from the further claims.
[0015] In the following, exemplary embodiments of the present invention are described with reference to the attached figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 shows a sectional view of a first exemplary embodiment of a mount, which is mounted on a frame structure, according to an exemplary embodiment of the present invention.
[0017] FIG. 2 shows a three-dimensional view of a first exemplary embodiment of a first cable mount section according to the present invention.
[0018] FIG. 3 shows a three-dimensional view of a first exemplary embodiment of a second cable mount section according to the present invention.
[0019] FIG. 4 shows a sectional view of the first cable mount section from FIG. 2 .
[0020] FIG. 5 shows a first exemplary embodiment of a plate-shaped element according to the present invention.
DETAILED DESCRIPTION
[0021] In the following description of FIGS. 1 through 5 , identical reference numbers are used for identical or corresponding elements.
[0022] FIG. 1 shows a sectional view of a first exemplary embodiment of a mount for an aircraft according to the present invention. As may be inferred from FIG. 1 , the mount is positioned in a hole or bore of a frame or former 6 . A support structure 16 of the frame 6 is shown in the background. As may be inferred from FIG. 1 , the mount has a first cable mount section 2 and a second cable mount section 4 . According to one exemplary embodiment of the present invention, the first and the second cable mount sections 2 and 4 are essentially implemented from a plastic material. The first and the second cable mount sections 2 , 4 may be manufactured using an injection molding method, for example. The first cable mount section 2 has an essentially L-shaped structure in section. The second cable mount section 4 also has an essentially L-shaped structure in section. The first cable mount section 2 has a part having dimensions such that it may be inserted through a recess 22 in an insulation material 10 . The first cable mount section 2 has an essentially flat surface on a first end to be placed on the frame 6 . A plate-shaped element 12 is provided on the part, wherein the dimensions of the plate-shaped element 12 are larger than the dimensions of the recess or the hole 22 in the insulation material. Cable receiver sections 24 , in which the cable may be laid to support it, are provided on a region opposing the first end of the first cable mount section 2 . The cables or line routes may then be attached using cable binders, for example. Line routes may have a diameter from 5 to 60 mm, for example. The mount may be implemented for “heavy” line routes having a diameter of approximately 15-60 mm, particularly for routes of 25 mm diameter.
[0023] Like the first cable mount section 2 , the second cable mount section 4 has two cable receiving regions 24 for receiving two line routes. Furthermore, the second cable mount section 4 has an end region opposite the cable receiving regions 24 , which has an essentially flat surface to be placed on the frame 6 .
[0024] The first cable mount section 2 and the second cable mount section 4 are connected using a connecting element 18 , 28 . The connecting element has a screw 28 , which is supported in the first cable mount section 2 . In particular, the head of the screw may be supported in the first cable mount section 2 . The nut 18 is supported in the second cable mount section 4 . The screw 28 may thus be inserted through the eyelet (the hole) 8 in the frame and the screw 28 may be screwed together with the nut 18 in the second cable mount section 4 , so that the first and the second cable mount sections 2 , 4 are clamped on the frame 6 .
[0025] A further plate-shaped element 14 , which has larger dimensions than a recess or hole 20 in the insulation material 10 , is provided on the second cable mount section 4 .
[0026] As may be inferred from FIG. 1 , because of the positioning of the plate-shaped elements 12 and 14 , which may be implemented using metal disks, for example, the insulation material 10 may be prevented from falling down, i.e., the insulation material 10 may be prevented from slipping off the mount even in the event of great heat, as in case of fire, for example, since the plate-shaped elements are supported by the connecting element having the screw 28 and the nut 18 . For this purpose, the nut 18 has dimensions which are larger than a recess 52 in the plate-shaped element 14 . In addition, the head of the screw 28 has dimensions which are larger than a recess 50 in the plate-shaped element 12 . In this way, for example, all of the plastic of the mount may melt without the securing of the insulation material 10 by the connecting element, comprising the screw 28 , the nut 18 , and the plate-shaped elements 12 and 14 , being endangered, since these elements may be implemented from a very heat-resistant or fire-resistant material. The screw 28 , the nut 18 , and the plate-shaped elements 14 and 12 may be implemented from metal.
[0027] The plate-shaped elements 12 and 14 may, for example, be incorporated into the plastic of the first cable mount section 2 and the second cable mount section 4 . For example, the plate-shaped elements 12 and 14 may be heated and pushed onto the plastic. Welding on through frictional welding is also possible. The plate-shaped elements 12 and 14 may be implemented in one piece with the first and second cable mount sections using an injection molding method, however.
[0028] Instead of the connecting element having the screw 28 and the nut 18 , a screw-lock system may also be provided, for example. An arbor having a barb, which is inserted into a corresponding support device in the other cable mount section and thus ensures a secure connection, may also be provided instead of the screw 28 .
[0029] The screw 28 and the nut 18 may each be pushed through openings provided laterally in the first cable mount section and the second cable mount section. However, it is also possible to cast the nut 18 and the screw 28 in one piece with the first cable mount section and the second cable mount section.
[0030] The plate-shaped elements 12 , 14 may be implemented as inmolded metal washers.
[0031] FIG. 2 shows a perspective view of a first exemplary embodiment of the cable mount section according to the present invention.
[0032] As may be inferred from FIG. 2 , this cable mount section 4 has two receivers 24 for line routes. As may be inferred from FIG. 2 , this cable mount section is a cable mount section into which a screw of the corresponding other cable mount section is to be inserted. The nut 18 may be inserted into a side region of the cable mount 4 through a recess 42 , for example. The plate-shaped element 14 is implemented in FIG. 2 as an essentially ellipsoidal metal washer, which is cast into the plastic of the cable mount section 4 .
[0033] FIG. 3 shows a perspective view of a cable mount section according to one exemplary embodiment of the present invention. As may be inferred from FIG. 3 , a screw 28 is provided in this cable mount section, which may be pushed into the cable mount section of FIG. 2 , for example, and then screwed together with the corresponding nut.
[0034] The screw 28 may, for example, be cast into the cable mount section 2 of FIG. 3 . However, it is also possible to insert a threaded rod from the front into a corresponding hole of the cable mount section and then attach this threaded rod in the cable mount section 2 using a fastener, which may be inserted laterally into a recess 40 . As may be inferred from FIG. 3 , the cable mount section 2 also has two cable receiving regions 24 . As in the cable mount from FIG. 1 , the plate-shaped element 12 is implemented using an essentially ellipsoidal metal washer which is cast into the plastic of the cable mount 2 . Instead of the metal washer or blank, manifold shaped elements may be used, as long as it is ensured that the eyelet in the insulation material may not slip over the shaped element.
[0035] FIG. 4 shows a sectional view of the cable mount from FIG. 2 . As may be inferred from FIG. 4 , a cable 46 , which may be attached using a cable binder, for example, may be received in the cable mount section 24 . It may be inferred from the sectional view of FIG. 4 that a hole 64 is provided in the cable mount section 4 , into which the screw 28 of the corresponding other cable mount section 2 may be inserted. This hole 64 is bored into the face of the area or surface 60 of the cable mount section 4 , which is implemented to be placed on the frame 6 . Furthermore, a space 62 for positioning the nut 18 is provided in the hole 64 . The nut, as already noted, may be inserted into the space 62 through a recess 42 , for example. As may be inferred from FIG. 4 , the nut 18 has dimensions that are larger than the recess 50 in the plate-shaped element 12 , which may be implemented using the ellipsoidal metal washer 14 , for example.
[0036] FIG. 5 shows a top view of an exemplary embodiment of the plate-shaped element 12 . The hatched middle region of the plate-shaped element 12 is the region which is cast with the plastic of the corresponding cable mount section. A hole 44 for inserting the screw 28 through is provided in the middle of the plate-shaped element 12 .
[0037] A cable mount is provided according to the present invention, which additionally assumes the function of securing insulation material, such as insulation mats, as are used for protecting frames in the aircraft against the effect of heat, for example. If the plastic melted in case of strong heating, for example, the insulation would still be supported between the metal blanks, whose diameter is larger than the eyes of the insulation mat, and thus offer more security.
[0038] It should be noted that the term “comprising” does not exclude other elements or steps and the “a” or “an” does not exclude a plurality. Also elements described in association with different embodiments may be combined.
[0039] It should also be noted that reference signs in the claims shall not be construed as limiting the scope of the claims. | A mount for an aircraft secures insulation material to a structure of the aircraft in which a plate-shaped element and a connecting element that are implemented from a very heat-resistant material are provided. The remainder of the hanger may be implemented from plastic. Under the effect of strong heat, the plastic may melt. An insulation mat is nonetheless secured against falling down/detaching by the plate-shaped element, which is supported using the connecting element. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to a device for feeding and cutting a strip of any type of material on a sewing machine.
Devices are already known which are designed to feed a strip of flexible material such as elastic material unwound from a continuous roll for the purpose of inserting it beneath the presser foot of a conventional sewing machine in order to sew the strip to a layer of fabric. These devices are also equipped with a device for cutting the strip so as to enable a piece of the same to be sewn to the layer of fabric.
According to the prior art, a guide is used for reinserting the strip piece, which has been precut from the roll, beneath the presser foot; the strip being made to slide along the guide by pushing means acting on the strip along the guide. As soon as the strip is inserted beneath the presser foot, it is removed from the roll by the feed mechanisms of the sewing machine.
The guide extends into the vicinity of the presser foot and the stitch forming mechanisms but it is spaced apart from the same to enable the cutting means to cut the strip at the end of the stitching operations. In the conventional devices, the distance between the lower end of the guide and the presser foot renders insertion of the strip beneath the presser foot extremely difficult in that the strip rolls up very easily owing to the inevitable folds or snags already present in the strip or produced by cutting the same. In any case, the strip, per se, will tend to roll up in front of the presser foot, particularly when the strip consists of extremely flexible material.
Furthermore, certain conventional devices are equipped with a delivery mechanism designed to facilitate insertion of the strip beneath the presser foot; this delivery mechanism being rigidly connected to the presser foot and its height being such that when the presser foot is raised it is moved against the end part of the guide so as to produce a continuous guide channel for the strip.
The disadvantage of this solution is that, as the presser foot is raised to different levels in different types of sewing machines, it will be necessary to provide delivery means of different height for each type of machine, thus reducing the space needed by the cutting devices which operate between the guide and the deliver means.
The object of the present invention is to render the device universally applicable and thus enable it to be used on any type of sewing machine regardless of the distance by which the presser foot is raised.
Another object of the present invention is that of also enabling the strip to be inserted beneath the presser foot when the sewing machine is in operation. The technical problem to be solved is that of producing a device in which the continuity of the guide channel is independent of the raising path of the presser foot without having to resort to position adjustment of the guide and the cutting device.
SUMMARY OF THE INVENTION
The above-defined technical problem is optimally solved by means of the device according to the present invention for cutting and inserting a strip beneath the presser foot of a sewing machine comprising a guide along which the strip is made to slide by pushing means during the stage of inserting the same beneath the presser foot; means for cutting the strip being disposed between the presser foot and the lower end part of the guide; characterized in that the device comprises means for moving the guide from a rest position remote from the stitching zone to a position for insertion of the strip beneath the presser foot and for returning this guide into the rest position after the strip has been inserted beneath the presser foot by the pushing means.
These and other features will be made apparent in the course of the following description of a preferred but not exclusive embodiment of the invention which is provided by way of a non-limitative example only with reference to the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a sewing machine equipped with the strip cutting and insertion device according to the present invention;
FIG. 2 is a lateral, partial sectional view of the strip insertion device;
FIG. 3 is a view from below the device shown in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1 the device according to the present invention is mounted on a conventional sewing machine 1 comprising a conventional base 2, to which the hollow part 3 is rigidly attached. The hollow part 3 supports the arm 4 whose free end houses, inter alia, the presser bar 5 bearing a presser foot 6 and the needle 7 carried by a conventional needle bar (not shown in the drawings).
The system for raising the presser foot 6 is pneumatic and will be described hereinafter. A plate 8 is attached to the end of the arm 4 of the sewing machine. An angular bracket 9 adapted to rotate about a hinge screw 10 is hinged to the plate 8. The rotation of the bracket 9 about the hinge screw 10 makes it possible to adjust the inclination of the entire device with respect to a vertical axis and to pivot the device until it is above the arm 4 of the sewing machine, thus facilitating any maintenance work on the stitching mechanisms. The bracket 9 supports a strip insertion device designated in total by the reference number 11. Referring now to FIG. 2, a slide plate 13 of a guide 14, in which a strip 15 is inserted, is attached by means of a screw 12 to the bracket 9. The plate 13 bears a slot 16 in which a stroke limiting member 17 is inserted. The member 17 also comprises a slot 18 enabling it to be positioned on the plate 13 by the locking action of a screw 19.
The plate 13 also comprises an orifice 20 through which a leadin plate 21 is passed. The plate 21 is attached by means of a screw 22 to the plate 13 and strip 15 slides along the same.
The guide 14 consists of a tubular element having a substantially rectangular section. At the upper part of one side it comprises a tooth 23 designed to cooperate with the stroke limiting member 17 and on its other side it comprises an aperture 24 running along its entire length. A plate 25 is adapted to be inserted in and to slide in the aperture 24. The plate 25 is attached by means of a screw 26 to a support 27 oscillating about a pin 28 supported by a first carriage 29 slidable along two rails 30 rigidly connected to the plate 13 by means of screws 31.
The rod 33 of a two-way pneumatic cylinder 34 is hinged at 32 to the support 27.
A small block 35 is attached to the first carriage 29. The block 35 is equipped with an adjustment screw 36 designed to strike against the support 27 and intended to limit the rotation of the support 27 about the pin 28.
A spring 38 is also attached to the block 35 by means of a screw 37. The spring 38 comprises a tooth 39 designed to be inserted in a seat 40 of a second carriage 41. The guide 14 is attached to the carriage 41 by means of a screw 42. The second carriage 41 is supported by two guide extensions 43 (FIG. 3) slidable along corresponding seats provided in the first carriage 29.
The second carriage 41 also comprises a groove 44 in which the tooth 39 of the spring 38 is adapted to slide.
A funnel delivery element 45 is rigidly connected to the presser foot 6. The element 45 has a rectangular section and is open at its lower part and laterally. The lower opening in the delivery element is disposed in the same plane as the base of the presser foot. Conventional scissor-type cutting means 46, controlled by a pneumatic cylinder 47, are disposed in the free zone between the opening of the delivery element and the lower end of the guide to the righthand side of the guide per se. The cutting means 46 used to cut the strip 15 is such that the pneumatic cylinder 47 not only produces the simultaneous closing or opening of cutting blades 48 but also the translational movement of the plates per se in the operating direction of the cylinder so as to move the cutting means towards or away from the zone between the delivery means and the guide; the strip 15 passing through this zone.
The mode of operation of the device will now be described in reference to FIGS. 1 and 2.
The preliminary operations consist in manually inserting the strip 15 into the guide 14 and beneath the plate 25 which, together with the cylinder 34, constitute the means for pushing the strip.
By depressing a push button 49 of a valve 50 inserted in a compressed air line, compressed air is introduced into the branch 51 which is used to raise the presser foot before the movement of the rod of the cylinder 34 is begun. The supplying of compressed air into the cylinder 34 in its upper part causes the plate 25 to be lowered. The plate 25 acts on the strip 15 and pushes it downwards. The supplying of air to the cylinder 34 simultaneously causes the guide 14 to be lowered owing to the fact that the tooth 39 supported by the first carriage displaced by the cylinder 34 pushes the second carriage 41 downwards. The spring 38 equipped with a tooth 39 and the second carriage 41 constitute the means for displacing the guide 14.
The downward movement of the second carriage 41 and of the guide 14 continues until the tooth 23 of the guide strikes against the stroke limiting member 17. At this point the guide is arrested and is now located in a position in which its lower end is in contact with the delivery means 45.
The path of the first carriage 29 and thus the downward movement of the strip 15, can continue owing to the fact that the tooth 39 is removed from its seat 40 and it slides in the guide groove 44.
The end of the strip 15 is carried beneath the presser foot in correspondence with the stitching mechanisms in that the stroke of the cylinder 34 is substantially equal to the distance between the lower end of the guide 14 and the stitching mechanisms.
A layer of fabric 52 can now be placed manually beneath the presser foot.
When the push button 49 is now released, the branch 51 ceases to be supplied and the air is switched to the branch 53. As a result, the cylinder 34 is supplied with air at its lower part and thus the first carriage 29 bearing the plate 25 is raised. As the latter is tilted, it does not drag behind it the strip 15.
When the first carriage reaches the seat 40, the tooth 39 is inserted therein. The tooth 39 pulls upwards the second carriage 41 and thus the guide 14. When the push button 49 is released, the presser foot is thus first lowered onto the strip 15, thus pinning down the same, and the carriage 29 is raised in the above-described manner. The rate at which the plate 25, and thus the piston of the cylinder 34 is lowered can be regulated by adjusting the stroke regulator 54. The sewing machine can now be started owing to the fact that the workpiece and the strip are already disposed beneath the presser foot. During the stitching operation the strip 15 is removed from the roller by the conventional feed mechanisms of the sewing machine and the plate 25 does not obstruct this removal operation owing to the fact that its pressure on the strip is so adjusted that it does not hamper the pulling action exerted on the strip by the feed mechanisms. When a specific length of strip has been attached to the layer of fabric 52, the sewing machine is stopped and a push button 55 is depressed. This causes the cylinder 47 operating the strip cutting means to be supplied. When the strip has been cut and the push button 55 released, the sewing machine can be restarted in order to sew the piece of the strip remaining in the deliver means, or alternatively the push button 49 can be depressed so as to raise the presser foot in order to remove the workpiece and reinsert the strip beneath the presser foot.
Although the present invention has been described in connection with a preferred embodiment, it is to be understood that modifications and variations may be resorted to without departing from the spirit and scope of the invention and the appended claims. | An improved mechanism for cutting and inserting a strip of elastic material or the like beneath the presser foot of a sewing machine in which guide means is provided which automatically adjusts its position relative to the presser foot regardless of the height of the presser foot and which feeds the elastic material into position for stitching beneath the presser foot. | 3 |
BACKGROUND OF THE INVENTION
The present invention concerns certain dipeptide esters and their users, particularly for ablation of certain cell-mediated immune responses. For brevity and clarity, many of the terms used herein have been abbreviated and these abbreviations include those shown in Table 1. Research involved in the development of the invention was supported by grants from the United States government.
L-leucine methyl ester (Leu-OMe) has previously been used as a lysosomotropic agent (Thiele et al. (1983) J. Immunol. V 131, pp 2282-2290; Goldman et al. (1973) J. Biol. Chem. V 254, p 8914). The generally accepted lysosomotropic mechanism involved leu-OMe diffusion into cells and into lysosomes, followed by intralysosomal hydrolysis to leucine and methanol. The more highly ionically charged leucine, largely unable to diffuse out of the lysosome, caused osmotic lysosomal swelling and rupture. The fate of leu-OMe subjected to rat liver lysosomes was additionally suggested by Goldman et al. (1973) to involve a transpeptidation reaction and a resultant species--"presumably the dipeptide" which was "further hydrolyzed to free amino acids". A subsequent and related paper by Goldman (FEBS (Fed. Europ. Biol. Sci.) Letters V 33, pp 208-212 (1973)) affirmed that non-methylated dipeptides were thought to be formed by lysosomes.
L-amino acid methyl esters have been specifically shown to cause rat liver lysosomal amino acid increases (Reeves (1979) J. Biol. Chem. V 254, pp 8914-8921). Leucine methyl ester has been shown to cause rat heart lysosomal swelling and loss of integrity (Reeves et al., (1981) Proc. Nat'l. Acad. Sci., V 78, pp 4426-4429).
TABLE 1______________________________________Abbreviations Symbol______________________________________SubstanceL-leucine leuL-phenylalanine pheL-alanine alaL-glycine glyL-serine serL-tyrosine tyrL-arginine argL-lysine lysL-valine valL-isoleucine ileL-proline proL-glutamic acid gluL-aspartic acid aspL amino acid methyl esters e.g. Leu--OMeL amino acid ethyl esters e.g. Leu--OEtD-amino acids e.g. D-LeuD-amino acids methyl esters e.g. D-Leu--OMedipeptides of L-amino acids e.g. Leu--Leumethyl esters of dipeptideL amino acids e.g. Leu--Leu--OMecell fraction or typemononuclear phagocytes MPpolymorphonuclear leucocytes PMNnatural killer cells NKperipheral blood mononuclear cells PBMcytotoxic T-lymphocytes CTLglass or nylon wool adherent cells ACglass or nylon wool non-adherent NACcellsOther Materialsphosphate buffered saline PBSthin layer chromatography TLCfluorescence activated cell sorter FACSmixed lymphocyte culture MLCMiscellaneouseffector:target cell ratio E:Tfetal bovine serum FBSUniversity of Texas Health UTHSCDScience Center, Dallas, Texas.Standard error of mean SEMprobability of significant pdifference (Student's t-test)Graft versus host disease GVHD______________________________________
Natural killer cells are large granular lymphocytes that spontaneously lyse tumor cells and virally-infected cells in the absence of any known sensitization. This cytotoxic activity can be modulated by a host of pharmacologic agents that appear to act directly on NK effector cells. NK activity has been shown to be augmented after exposure to interferons (Gidlund et al., Nature V 223, p 259), interleukin 2, (Dempsey, et al. (1982) J. Immunol. V 129, p 1314) (Domzig, et al. (1983) J. Immunol. V 130, p 1970), and interleukin 1 (Dempsey et al. (1982) J. Immunol. V 129, p 1314), whereas target cell binding is inhibited by cytochalasin B, (Quan, et al. (1982) J. Immunol. V 128, p 1786), dimethyl sulfoxide, 2-mercaptoethanol, and magnesium deficiency (Hiserodt, et al. (1982) J. Immunol. V 129, p 2266). Subsequent steps in the lytic process are inhibited by calcium deficiency (Quan et al. (1982) J. Immunol. V 128, p 1786, Hiserodt, et al. (1982) J. Immunol. V 129, p 2266), lysosomotropic agents (Verhoef, et al. (1983) J. Immunol. V 131, p 125), prostaglandin E 2 (PGE 2 (Roder, et al. (1979) J. Immunol. V 123, p 2785, Kendall, et al. (1980) J. Immunol. V 125, p 2770), cyclic AMP (Roder, et al. (1979) J. Immunol. V 123, p 2785, Katz (1982) J. Immunol. V 129, p 287), lipomodulin (Hattori, et al. (1983) J. Immunol. V 131, p 662), and by antagonists of lipoxygenase (Seaman (1983) J. Immunol V 131 p 2953). Furthermore, it has been demonstrated that PGE 2 and reactive metabolites of oxygen produced by monocytes (MP) or polymorphonuclear leukocytes (PMN) can inhibit NK cell function (Koren, et al. (1982) Mol. Immunol. V 19, p 1341; and Seaman, et al. (1982) J. Clin. Invest. V 69, p 876).
Previous work by the present applicants has examined the effect of L-leucine methyl ester on the structure and function of human peripheral blood mononuclear cells (PBM) (Thiele, et al. (1983) J. Immunol. V 131, p 2282.
Human peripheral blood mononuclear cells (PBM) are capable of mediating a variety of cell-mediated cytotoxic functions. In the absence of any known sensitization, spontaneous lysis of tumor cells and virally-infected cells is mediated by natural killer cells (NK) contained within the large granular lymphocyte fraction of human PBM Timonen et al. (1981) v. J. Exp Med. V 153 pp 569-582. After lymphokine activation, additional cytotoxic lymphocytes capable of lysing a broad spectrum of tumor cell targets can be generated in in vitro cultures (Seeley et al. (1979) J. Immunol. V 123, p 1303; and Grimm et al. (1982) J. Exp. Med. V 155, p 1823). Furthermore, lymphokine activated peripheral blood mononuclear phagocytes (MP) are also capable of lysing certain tumor targets (Kleinerman et al. (1984) J. Immunol. V 133, p 4). Following antigen-specific stimulation, cell-mediated lympholysis can be mediated by cytotoxic T lymphocytes (CTL).
While a variety of functional and phenotypic characteristics can be used to distinguish these various types of cytotoxic effector cells, a number of surface antigens and functional characteristics are shared. Thus, the antigens identified by the monoclonal antibodies OKT8 (Ortaldo et al. (1981) J. Immunol. V 127, p 2401; and Perussia et al. (1983) J. Immunol. V 130, p 2133), OKT11 (Perussia et al. (1983) J. Immunol. V 130, p 2133; and Zarling et al. (1981) J. Immunol. V 127, p 2575), NK9 (Nieminen et al. (1984) J. Immunol. V 133, p 202) and anti-D44 (Calvo et al. (1984) J. Immunol. V 132, p 2345) are found on both CTL and NK while the antigen identified by OKM1 is shared by MP and NK (Zarling et al. (1981) J. Immunol. V 127, p 2575; Ortaldo et al. (1981) J. Immunol. V 127, p 2401; Perussia et al. (1983) J. Immunol. V 130, p 2133; and Breard et al. (1980) J. Immunol. V 124, p 1943. Furthermore, cytolytic activity of both NK and MP is augmented by interferons, (Kleinerman et al. (1984) J. Immunol. V 133, p 4; Gidlund et al. (1978) Nature V 223, p 259; and Trinchieri et al. (1978) J. Exp. Med. V 147, p 1314). Finally, use of metabolic inhibitors has demonstrated some parallels in the lytic mechanism employed by CTL and NK (Quan et al. (1982) J. Immunol. V 128, p 1786; Hiserodt et al. (1982) J. Immunol. V 129, p 1782; Bonavida et al. (1983) Immunol. Rev. V 72, p 119; Podack et al. (1983) Nature V 302, p 442; Dennert et al. (1983) J. Exp. Med. V 157, p 1483; and Burns et al. (1983) Proc. Nat'l. Acad. Sci. V 80, p 7606).
SUMMARY OF THE INVENTION
An alkyl ester of dipeptides consisting essentially of natural or synthetic L-amino acids with hydrophobic side chains. Preferable amino acids are leucine, phenylalanine, valine, isoleucine, alanine, proline, glycine or aspartic acid beta methyl ester. Preferable dipeptides are L leucyl L-leucine, L-leucyl L-phenylalanine, L-valyl L-phenylalanine, L-leucyl L-isoleucine, L-phenylalanyl L-phenylalanine, L-valyl L-leucine, L-leucyl L-alanine, L-valyl L-valine, L-phenylalanyl L-leucine, L-prolyl L-leucine, L-leucyl L-valine, L-phenylalanyl L-valine, L glycyl L-leucine, L-leucyl L-glycine or L-aspartyl beta methyl ester L-phenylalanine. The most preferable dipeptides are L-leucyl L-leucine, L-leucyl L-phenylalanine, L-valyl L-phenylalanine, L-phenylalanyl L-leucine, L-leucyl L-isoleucine, L-phenylalanyl L-phenylalanine and L-valyl L-leucine.
The alkyl ester of the dipeptide is most preferably a methyl ester and may also be an ethyl ester or alkyl of up to about four carbon atoms such as propyl, isopropyl, butyl or isobutyl.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows that whereas ablation of NK function during incubation with Leu-OMe can be blocked by lysosomotropic agents, there is a product formed during incubation of Leu-OMe with MP or PMN which has effects on NK function no longer blocked by lysosomal inhibitors.
FIG. 2 shows Leu-OMe products of PMN in terms of radioactivity and NK suppressive effects of TLC fractions.
FIG. 3 shows, the CI mass spectra of TLC fractions with NK toxic activity and of synthetic Leu-Leu-OMe.
FIG. 4 shows the effects of various agents on losses of NK function from MP-depleted lymphocytes.
FIG. 5 shows the NK-toxicity of various dipeptide esters.
FIG. 6 shows the loss of NK and MP from PBM incubated with Leu-Leu-OMe at various concentrations.
FIG. 7 shows the toxicity of various Leu-Leu-OMe concentrations for selected cell types.
FIG. 8 shows the Leu-Leu-OMe mediated elimination of precursors of cytotoxic T lymphocytes, activated NK (A c NK) and NK.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present invention concerns new compounds and their uses in ablating particular cell types and their functions. The presently described invention relates to the discovery that dipeptide alkyl esters are cytotoxic metabolites of lysosomotropic amino acid alkyl esters.
It has further been found that alkyl esters of dipeptides consisting essentially of natural or synthetic amino acids with hydrophobic side chains may function cytotoxically to deactivate natural killer cells (NK) and cytotoxic T lymphocytes (CTL). By the term "hydrophobic" as used herein, is meant uncharged in aqueous solution at physiological pH and also as having no hydroxyl, carboxyl or primary amino groups.
Treatment of NK or CTL with an effective level of an alkyl ester of a dipeptide consisting essentially of natural or synthetic amino acids with hydrophobic side chains serves to deactivate the cytotoxic functions of said cells. An effective level varies from circumstance to circumstance but generally lies between about 25 micromolar and about 250 micromolar. An effective level for a whole animal dose generally lies between about 100 mg/kg and about 300 mg/kg.
Both methyl and ethyl esters of dipeptides consisting essentially of natural or synthetic amino acids having hydrophobic side chains have been specifically found to deactivate natural killer cells or cytotoxic T lymphocytes and other alkyl esters of these dipeptides are confidently predicted to have similar or superior effects.
Deactivation of natural killer cells (NK) or CTL cells with such dipeptide alkyl esters should increase the success of allogeneic bone marrow transplants by lowering the incidence of graft-versus-host disease (GVHD) and by lowering the incidence of transplant rejection.
Graft versus host disease (GVHD) is a major problem in allogeneic bone marrow transplantation. It occurs in approximately 70% of transplant recipients and causes death in 20% of those (Wells, et al. p 493 in Basic and Clinical Immunology. Fundenbergo et al. (editors) 2nd ed. Lange, (1978)). The disease occurs when cells of the graft (donor) attack the host tissue, causing abnormalities in the immune system and gastrointestinal tract, as well as skin rashes and liver dysfunction. Although cytotoxic T lymphocytes have traditionally been considered to be the primary effector cells in GVHD, recent studies have shown a correlation between the occurrence of the disease and the appearance of NK activity soon after transplantation. These results implicate the donor's NK cells in the etiology of GVHD. Moreover, other studies demonstrate that high levels of NK activity in a bone marrow recipient prior to transplantation are associated with GVHD (Dokhelar et al. (1981) Transplantation V 31 p 61; Lopez et al. (1979) Lancet V 2 p 1103; and Lopez et al. (1980) Lancet V 2 p 25). Thus, it is theorized that both host and donor NK cells contribute to the development of the disease.
Current regimens for the prevention and treatment of GVHD consist of depleting T-lymphocytes from the donor marrow prior to transplantation and giving the recipient immunosuppressive drugs such as cyclophosphamide and methotrexate, both before and after transplantation. The effectiveness of these regimens might be enhanced by treating donor bone marrow and transplant recipients with dipeptide methyl esters. Potential problems with these procedures include possible non-specific toxicity of therapeutic dipeptide alkyl esters and the re-emergence of NK activity from precursors not sensitive to therapeutic dipeptide alkyl esters.
Currently, bone marrow transplantation is used as a major mode of therapy in treating aplastic anemia, acute myelogenous leukemia, and a variety of immunodeficiency states. As mentioned above, a major complication of this therapy is graft-versus-host disease (Sullivan et al., Blood V 57, p 207). Severity of GVHD in man correlates with pretransplant levels of natural killer (NK) activity (Lopez et al., Lancet V 2, p 2101). Thus, by virtue of its ability to diminish NK function in vivo, it is contemplated that Leu-Leu-OMe administration, for example, to bone marrow samples prior to their transplantation will be efficacious in diminishing this complication. An effective level of the dipeptide alkyl esters of the present invention for in vitro deactivation of natural killer cells is between about 10 micromolar and about 250 micromolar.
Furthermore, in both murine and human models, the incidence of GVHD is decreased by in vitro treatment of donor bone marrow with agents that deplete mature T cells (Korngold et al., Exp. Med. V 148, p 1687; Reisner et al., Blood V 61, p 341). Since cytotoxic T cells (CTL) derived from donor bone marrow appear to be the final mediators of GVHD, in vitro treatment of donor bone marrow with an agent which selectively damages cytotoxic T cell precursors is also likely to be of benefit. Since such an in vitro action of Leu-Leu-OMe has now been demonstrated it is expected that this agent will be of benefit in pretreating donor bone marrow. An effective level of the dipeptide alkyl esters of the present invention for treatment of bone marrow to be transplanted should be between about 10 micromolar and 250 micromolar for ablation of GVHD-mediating CTL and NK.
A second problem in bone marrow transplantation is the failure of engraftment (the transplant does not "take" or is rejected). This problem occurs in 10-20% of transplants and can be caused by several factors, including improper transplantation technique, extensive invasion of the recipient's bone marrow by tumor cells, and rejection of the transplant.
The discovery that F 1 mice could reject transplants of parental bone marrow first indicated that NK cells might be involved in the engraftment failures (Cudkowicz et al. (1971) J. Exp. Med. V 134, p 83; Cudkowicz et al. (1971) J. Exp. Med. V 134, p 1513; and Kiessling et al. (1977) Eur. J. Immunol. V 7, p 655).
Initially graft rejection was thought to be almost totally dependent on T lymphocytes. However, T cells from an F 1 hybrid animal do not normally attack parental tissue. Therefore, it was suggested that NK cells, not T cells, mediated the rejection of the parental bone marrow.
Additional support for this hypothesis was derived from the observation that mice of a strain normally incapable of rejecting bone marrow transplants acquire this ability when they are injected with cloned NK cells. (Warren et al. (1977) Nature V 300, p 655). As a result of these findings, Herberman et al. ((1981) Science V 214), p 24 have suggested that suppression of NK activity might lower the incidence of transplant rejection. This suppression should be achieved by treating the recipient with the dipeptide methyl esters of the present invention prior to transplantation.
Other clinical uses for alkyl esters of dipeptides consisting essentially of amino acids with hydrophobic side chains, or other situations where NK or CTL are involved in the pathogenesis of disease. In organ transplants in general (kidney, heart, liver, pancreas, skin, etc.) it is widely accepted that cytotoxic T cells are likely to be the cell type responsible for graft rejection (Mayer et al., J. Immunol. V 134, p 258). Thus, it is contemplated that the in vivo administration of Leu-Leu-OMe or similar dipeptide esters of the present invention will be of benefit in preventing allograft rejection.
It is also contemplated that Leu-Leu-OMe or other alkyl dipeptide esters may be of benefit in other spontaneously occurring disease states. A variety of diseases have been classified as "autoimmune diseases" because of the widely accepted belief that they are caused by disorders in the immune system which cause immunologic damage to "self". Thus, in a variety of diseases, including primary biliary cirrhosis, systemic lupus erythematosus, rheumatoid arthritis, multiple sclerosis, autoimmune hemolytic anemia, etc., various forms of immunologic damage to selected organs occur. In some of these diseases, such as primary biliary cirrhosis, the histologic abnormalities which occur (in this case in the liver) closely resemble those which occur in GVHD or in rejection of a transplanted liver (Fennel, (1981), Pathol. Annu. V 16 p 289. Thus, it is reasonable that similar mechanisms of cytotoxic lymphocyte damage to liver cells may be occurring, and therefore benefit from therapy with Leu-Leu-OMe or other dipeptide alkyl esters of the present invention should also occur in such disease states.
The dipeptide alkyl esters of the present invention should be usable chemotherapeutic agents in patients with natural killer cell tumors (generally leukemias), although very few reports of these tumors are found in the literature (Komiyama et al. (1982) Blood V 60, p 1428 (1982); Itoh et al. (1983) Blood V 61, p 940; Komiyama et al. (1984) Cancer V 54 p 1547.
It is contemplated that the dipeptide alkyl esters of the present invention may also be used to treat patients with aplastic anemia and other types of bone marrow dysfunction. This suggestion is based on three sets of observations in human studies: first, NK cells can kill normal bone marrow cells (Hansson, et al. (1981) Eur. J. Immunol. V 11, p 8th); second NK cells inhibit growth of blood cell precursors in vitro (Hansson, et al. (1982) J. Immunol. V 129, p 126; Spitzer et al.: Blood V 63, p 260; Torok-Storb et al. (1982) Nature V 298, p 473; Mangan, et al. Blood V 63, p 260); and third, NK-like cells with the ability to inhibit the formation of red blood cells with the ability to inhibit the formation of red blood cells have been isolated from patients with aplastic anemia (Mangan, et al. (1982) J. Clin. Invest. V 70, p 1148; and Nogasawa et al. (1981) Blood V 57, p 1025). Moreover, recent studies in the mouse indicate that NK cells may function to suppress hemopoiesis in vivo (Holmberg et al. (1984) J. Immunol. V 133, p 2933). However, further investigation is desireable before the connection between NK activity and bone marrow dysfunction is considered conclusive.
Generally, when the dipeptide alkyl esters of the present invention are administered to animals, an effective level is between about 1×10 -4 moles/kg and about 1×10 -2 moles/kg.
The following Examples are presented to more fully illustrate preferred embodiments of the present invention and are not intended to limit the invention unless otherwise so stated in the accompanying claims.
EXAMPLE 1
Cell Preparations and Assays
PBM were separated from heparinized venous blood of healthy donors by centrifugation over sodium diatrizoate-Ficoll gradients (Isolymph, Gallard-Schlesinger Chemical Mfg. Corp., Carle Place, NY). Monocyte-enriched populations (MP) were prepared from glass adherent cells and MP-depleted lyphocytes from the nonadherent cells remaining after incubation in glass Petri dishes and passage through nylon wool columns as detailed in Rosenberg et al. (1975) (J. Immunol V 122, pp 926-831). PMN were collected by resuspending peripheral blood cells that penetrated sodium diatrizoate-Ficoll gradients and removing erythrocytes nu dextran sedimentation and hypotonic lysis as previously outlined (Thiele et al. (1985) J. Immunol. V 134, pp 786-793.
All cell exposures to the amino acids, dipeptides or their methyl esters were carried out by suspending cells in Dulbecco's phosphate buffered saline (PBS) and incubating them at room temperature with the reagent at the indicated concentration and time interval. After incubation, the cells were washed twice with Hanks' balanced salt solution and resuspended in medium RPMI 1640 (Inland Laboratories, Fort Worth, TX) supplemented with 10% fetal bovine serum (Microbiological Associates, Walkersville, MN) for assay of function.
Natural killing against K562 target cells was assessed by a 3 hour 51 Cr release assay and percent specific lysis calculated as previously described (Thiele et al. (1985) J. Immunol. V 134, pp 786-793). Percent of control cytotoxicity was calculated using the formula: ##EQU1##
EXAMPLE 2
General Procedures for Generation, Purification and Characterization of L-leucine Methyl Ester and Its Metabolites
MP or PMN (prepared as in Example 1) at a concentration of 25×10 6 per ml were suspended in PBS and incubated with 25 mM Leu-OMe for 20 minutes at 22° C. Cell suspensions were then centrifuged at 1000 g for 10 minutes and the supernatants harvested and freeze-dried at -70° C., 100 millitorr atmospheric pressure. In some experiments, Leu-OMe-treated MP or PMN were sonicated to increase the yield of the reaction product. Samples were then extracted with methanol for application to thin layer chromatography (TLC) plates (200 micromolar×20 cm 2 , Analtech, Newark, Delaware). Following development with chloroform/methanol/acetic acid (19:1:12.5 by volume), 1 cm bands were eluted with methanol, dried under nitrogen, and resuspended in 1 ml PBS. Mass spectra were obtained with a Finnegan Model 4021 automated EI/CI, GC/MS system coupled to an Incos data system. Methane was used as the reagent gas for chemical ionization (CI) mass spectral analysis.
EXAMPLE 3
Lysosomotropic Substances and Formation of NK-toxic Products
The addition of Leu-OMe to human PBM was shown to cause rapid death of MP and NK cells but not T or B lymphocytes (Thiele et al. (1985) J. Immunol. V 134, pp 786-793; Thiele et al. (1983) J. Immunol. V 131, pp 2282-2290). Amino acid methyl esters are known to be lysosomotropic compounds, and in previous studies it was found that the lysosomal inhibitors, chloroquine and NH 4 Cl, prevented Leu-OMe-induced MP toxicity. To assess whether these agents similarly prevented formation of any NK toxic products, the following experiments were carried out, and the results shown in FIG. 1.
PBM (prepared as in Example 1) were incubated with various potential NK toxic agents in the presence or absence of various lysosomal inhibitors for 40 minutes, washed to remove the inhibitor, incubated for 18 hours to permit recovery from any transient inhibition caused by lysosomotropic agents and then tested for NK activity. As can be seen in FIG. 1, neither chloroquine, NH 4 Cl, nor Ile-OMe had any substantial permanent effect on NK function. In contrast, 5 mM Leu-OMe ablated all NK activity. This activity of Leu-OMe was largely prevented by chloroquine, NH 4 Cl, or Ile-OMe. The products generated by MP or PMN, after exposure to Leu-OMe also completely removed all NK activity from PBM. In contrast to the effect noted with Leu-OMe, the lysosomal inhibitors did not protect NK cells from the action of this product(s). Additional experiments indicated that the sonicates of MP or PMN had no effect on NK function in this system whereas the supernatants or sonicates of Leu-OMe treated PMN or MP also depleted NK cells from MP depleted lymphocytes. These results therefore suggest that interaction of Leu-OMe with the lysosomal compartment of MP or PMN produced a product which was directly toxic to NK cells through a mechanism that was no longer dependent on lysosomal processing within the NK cell or an additional cell type.
More particularly, the conditions of the manipulations leading to the results shown in FIG. 1 were as follows:
Inhibitors of lysosomal enzyme function prevent generation of an NK toxic product. PBM (5×10 6 /ml) or PMN (25×10 6 /ml) preincubated with 25 mM Leu-OMe for 30 minutes were added to cells to be ablated. Cells were incubated with these agents for another 30 minutes at 22° C., then washed and cultured for 18 hours at 37° C. before assay of the ability to lyse K562 cells. Data are expressed as percentage of control cytotoxicity observed with an effector:target ratio of 40:1 (results at other E:T were similar).
EXAMPLE 4
Ablation of NK Function by PMN Produced Leu OMe Product
When the NK toxic properties of MP-Leu-OMe, or PMN-Leu-OMe incubation mixtures were evaluated, it was found that this activity was stable in aqueous solutions for more than 48 hours at 4° C., but labile at 100° C., retarded on Sephadex G-10 columns; dialyzable through 1000 MWCO (molecular weight cut-off) membranes, and could be extracted by chloroform-methanol (3:1, by volume). As shown in FIG. 2, when 14 C-leucine methyl ester was incubated with PMN and the supernatants subsequently separated by TLC, three major peaks of 14 C activity were found. One of these peaks corresponded to leucine methyl ester itself and one to free leucine while the third represented a new product. This third peak accounted for about 10% of the total 14 C-labeled material. When MP-depleted lymphocytes were exposed to each TLC fraction, the third peak was found to contain all NK toxic activity. This NK toxic activity not only appeared to be 14 C labeled but was also ninhydrin positive, suggesting that it was a metabolite which still retained an amino group as well as part of the carbon structure of Leu-OMe. An identical 14 C labeled ninhydrin positive product was detected by TLC of MP-Leu-OMe incubation mixture supernatants or sonicates. The production by PMN or MP of this metabolite was inhibited by chloroquine, NH 4 Cl, or Ile-OMe (data not shown).
Ablation of NK function is mediated by a metabolite of Leu-OMe. PMN (25×10 6 /ml) were incubated with 25 mM 14 C-Leu-OMe for 30 minutes and supernatants harvested for TLC analysis. MP-depleted lymphocytes (2.5×10 6 cells/ml) were exposed to varying dilutions of each TLC fraction for 30 minutes, washed and cultured for 2 hours prior to cytotoxicity assay at E:T ratio of 20:1. Samples were considered to contain an NK toxic product when percent specific lysis was less than 25% of control. FIG. 2 shows these results.
EXAMPLE 5
Characterization Of The NK-toxic Metabolite
The nature of the new TLC peak found as described in Example 4 was examined by mass spectroscopy. As shown in FIG. 3A, when the TLC-purified, NK-toxic fraction was subjected to more spectral analysis, results showing peaks at M/Z 259 (Mn+), 287 (M+C 2 H 5 +) and 299 (M+C 3 H 5 +) indicated the presence of a compound of molecular weight 258. The presence of peaks at M/Z 244 (M + --CH 3 ) and 272 (M+C 2 H 5 5 + --CH 3 ) suggested that this compound contained a methyl ester group. Furthermore, the persistence of peaks corresponding to leucine (MN + =131, M+C 2 H 5 =159) and leucine methyl ester (MH + =146, M+C 2 H 5 + =174) in spite of careful TLC purification of the NK toxic product from any free leucine or Leu-OMe present in the crude supernatants of the incubation mixtures suggested that a condensation product of Leu-OMe such as Leu-Leu-OMe (MW258) was present in the NK toxic fraction isolated after incubation of PMN or MP with Leu-OMe.
When Leu-Leu-OMe was synthesized from reagent grade Leu-Leu, by incubation in methanol hydrochloride, it was found to have TLC mobility identical to NK toxic fractions of MP-Leu-OMe or PMN-Leu-OMe incubation mixtures. Furthermore, its CI mass spectrum as shown in FIG. 3B was identical to that of the 258 molecular weight compound found in these incubation fractions.
Experiments further confirmed that Leu-Leu-OMe was the product generated by MP or PMN from Leu-OMe that was responsible for the selective ablation of NK function from human lymphocytes. Leu-Leu-OMe was synthesized by addition of Leu-Leu to methanolic HCl. TLC analysis revealed less than 2% contamination of this preparation with leucine, Leu-Leu, or leu-OMe, and CI mass spectral analysis (FIG. 3B) revealed no contaminants of other molecular weights.
FIG. 3A shows the chemical-ionization CI mass spectra of TLC fractions with NK toxic activity as described in FIG. 2, and also of Leu-Leu-OMe synthesized from reagent grade Leu-Leu (FIG. 3B).
EXAMPLE 6
In the representative experiments shown in FIG. 4, MP-depleted lymphocytes were exposed to varying concentrations of Leu-Leu-OMe for 15 minutes at room temperature, then washed and assayed for ability to lyse K562 cells. No NK function could be detected in lymphocyte populations exposed to greater than 50 micromolar Leu-Leu-Ome. As previously demonstrated (Thiele et al. (1983) J. Immunol. V 131 pp 2282-2300), exposure of such MP-depleted lymphocyte populations to 100 fold greater concentration of leucine or leu-OMe had no irreversible effect on NK function. Leu-Leu or the D-stereoisomer, D-Leu-D-Leu-OMe, also had no inhibitory effect. While Leu-Leu-Leu-OMe caused dose-dependent loss of NK function, 5-fold greater concentrations of this tripeptide methyl ester were required to cause an effect equivalent to that of the dipeptide methyl ester of L-leucine. When lymphocyte populations exposed to varying concentrations of Leu-Leu-OMe were further analyzed, it was found that exposure to more than 50 micromolar Leu-Leu-OMe resulted in the loss of K562 target binding as well as complete depletion of cells stained by Leu 11b, and anti-NK cell monoclonal antibody (data not shown). Thus, the MP- or PMN-generated product of Leu-OMe which is directly toxic for human NK cells is the dipeptide condensation product Leu-Leu-OMe.
The condition of the manipulations resulting in the data leading to FIG. 4 are further detailed as follows: for loss of NK function after exposure to Leu-Leu-OMe, MP-depleted lymphocytes (2.5×10 6 cells/ml) were incubated for 15 minutes with the indicated concentrations of leucine containing compounds. Cells were then washed, cultured at 37° C. for 2 hours (Expt. 1) or 18 hours (Expt. 2) and then assayed for NK activity. Results are given for E:T ratio of 20:1.
EXAMPLE 7
NK Ablation by a Variety of Dipeptide Methyl Esters
In previously reported studies, Leu-OMe was unique among a wide variety of amino acid methyl esters in its ability to cause MP or PMN dependent ablation of NK cell function from human PBM (Thiele et al. (1985) J. Immunol. V 134, pp 786-793). The identification of Leu-Leu-OMe as the MP-generated metabolite responsible for this phenomenon suggested that either MP/PMN did not generate the corresponding dipeptide methyl esters in toxic amounts from other amino acids, or that Leu-Leu-OMe was unique among dipeptide methyl esters in its toxicity for NK cells. Therefore, experiments were carried out to assess the effect of other dipeptide methyl esters on NK cell function. The methyl esters of a variety of dipeptides were synthesized and analyzed for the capacity to deplete NK cell function. Each dipeptide methyl ester was assessed in a minimum of three esperiments. As is shown by the results displayed in FIG. 5, Leu-Leu-OMe is not the only dipeptide methyl ester which exhibits NK toxicity. When amino acids with hydrophobic side chains were substituted for leucine in either position, the resulting dipeptide methyl ester generally displayed at least some degree of NK toxicity. In particular, Leu-Phe-OMe, Phe-Leu-OMe, Val-Phe-OMe, and Val-Leu-OMe produced concentration-dependent ablation of NK function at concentrations comparable to those at which Leu-Leu-OMe was active. The sequence of active amino acids was important, however, as evidenced by the finding that Phe-Val-OMe was markedly less active than Val-Phe-OMe. Similarly, Leu-Ala-OMe was NK inhibiting, whereas 10-fold greater concentrations of Ala-Leu-OMe had no NK inhibitory effects. Furthermore, Phe-Phe-OMe was less NK toxic than either Leu-Phe-OMe or Phe-Leu-OMe and Val-Val-OMe was less active than either Leu-Val-OMe or Val-Leu-OMe, yet Val-Phe-OMe was among the most potent of the NK toxic dipeptide methyl esters. Thus, conformational aspects of the dipeptide methyl ester amino acid side chain also seem to be of importance in producing the different levels of observed NK toxicity.
When amino acids with hydrophilic, charged or hydrogen side chains were substituted for leucine, the resulting dipeptide methyl esters either had greatly reduced NK toxicity, as in the case of Gly-Leu-OMe or Leu-Gly-OMe, or no observed NK inhibitory effects, as in the case of Leu-Arg-OMe, Leu-Tyr-OMe, Ser-Leu-OMe, Lys-Leu-OMe or Asp-Phe-OMe. Furthermore, when the D-stereoisomer was present in either position of a dipeptide methyl ester, no toxicity was observed for NK cells (FIG. 5). When unesterified dipeptides were assessed for their effect on NK function, as in the case of Leu-Leu (FIG. 4), up to 5×10 -3 M concentrations of Leu-Phe, Phe-Leu, Val-Leu, and Val-Phe had no effect on NK cell survival or lytic activity (data not shown).
D-Leu-D-Leu-OMe had no effect on Leu-Leu-OMe mediated NK toxicity although high levels of zinc appeared to inhibit this Leu-Leu-OMe toxicity.
Previous experiments had demonstrated that compounds such as Val-OMe, Phe-OMe, or combinations of Val-OMe and Phe-OMe did not delete NK function from human PBM (Thiele et al. (1985) J. Immunol. V 134, pp 786-793), despite the current finding that dipeptide methyl esters containing these amino acids were potent NK toxins. In order to determine whether MP or PMN could generate the relevant dipeptide methyl esters from these amino acid methyl esters, TLC analysis of the supernatants of MP and PMN incubated with these compounds was carried out. It was found that MP and PMN did generate detectable amounts of dipeptide methyl esters from these L-amino acid methyl esters. However, when equal concentrations of Leu-OMe, Val-OMe, or Phe-OMe were added to MP or PMN, the concentrations of Val-Val-OMe generated were 50 to 80% of those found for Leu-Leu-OMe, while Phe-Phe-OMe was detected at only 10-30% of the levels of Leu-Leu-OMe. Dipeptide methyl esters were not generated from D-amino acid methyl esters.
FIG. 5 shows the NK toxicity of dipeptide methyl esters. MP-depleted lymphocytes were treated with varying concentrations of dipeptide methyl esters as outlined in FIG. 4. Results are given for the mean±SEM of at least 3 separate experiments with each compound.
EXAMPLE 8
NK Toxicity of an Artificially Hydrophobic Dipeptide Methyl Ester
Beta methyl aspartyl phenylalanine was prepared by methanolic hydrochloride methylation of aspartyl phenylalanine methyl ester. The NK toxicity of both aspartyl phenylalanine methyl ester and beta methyl aspartyl phenylalanine methyl ester was measured as described for the dipeptide methyl esters in Example 7. As the data in Table 2 indicates, when the polar side chain of the aspartyl amino acid dipeptide component is esterified with a methyl group, this being a conversion from relative hydrophilicity to substantial hydrophobicity, NK toxicity becomes apparent. Although yet not as toxically effective as a number of the hydrophobic-type dipeptides in Example 7, the data in Table 2 indicate that a dipeptide methyl ester comprising synthetic hydrophobic (lipophilic) amino acids may be used to inhibit NK function.
TABLE 2______________________________________L-ASPARTYL (beta-METHYL ESTER)-L-PHENYLALANINEMETHYL ESTER IS NK TOXIC WHILE L-ASPARTYL-L-PHENYLALANINE METHYL ESTER IS NOT NK FunctionPreincubation % Specific Cytotoxicity______________________________________Nil 50.8Asp--Phe--OMe:100 micromolar 54.2250 micromolar 45.7500 micromolar 45.71000 micromolar 46.9Asp--(beta-OMe)--Phe--OMe:100 micromolar 38.9250 micromolar 13.9500 micromolar 2.81000 micromolar -0.1______________________________________
EXAMPLE 9
In Vivo Effects on Cytotoxic Cell Function
Leu-Leu-OMe or Leu-Phe-OMe were suspended in PBS, pH 7.4. Then individual C3H/HeJ mice (25 gram size) were administered by tail-vein injection either 2.5×10 -5 moles (6.5 mg) of Leu-Leu-OMe, 2.5×10 -5 moles (7.1 mg) Leu-Phe-OMe, or an equal volume of the PBS diluent, this dose being about 1×10 -3 moles per kg. For 15-30 minutes post-injection, Leu-Leu OMe and Leu-Phe OMe-treated animals but not the control animals exhibited decreased activity and an apparent increase in sleep. Subsequent to this quiescent period no difference in activity or appearance in the mice was noted. Two hours post-injection, the mice were sacrificed and their spleen cells were assayed for NK function in a standard 4 hour assay against YAC-1 tumor targets. In all mice, total cell recovery ranged from 1×10 8 to 1.1×10 8 spleen cells per animal. As noted in Table 3, the control mouse spleen cells exhibited greater killing at 25:1 and 50:1 effector to target cell ratios than did the spleen cells of treated mice at 100:1 and 200:1 E/T, respectively. Thus, Leu-Leu-OMe or Leu-Phe-OMe caused a greater than 75% decrease in splenic lytic activity against YAC-1 tumor targets.
TABLE 3______________________________________Cytotoxic Cell Function Effector:Target Ratio 25:1 50:1 100:1 200:1 Percent lysis of target cells______________________________________Control 8.29 12.88 20.60 29.29Leu--Leu--OMe 2.37 4.58 7.12 12.77Leu--Phe--OMe 3.89 4.68 6.91 11.91______________________________________
EXAMPLE 10
Differential Sensitivity of Natural Killer Cells (NK) and Mononuclear Phagocytes (MP) to Leucylleucine-Methyl Ester (Leu-Leu-OMe)
In the experiments depicted in FIG. 6, freshly isolated PBM (2.5×10 6 /ml PBS and 1 g/l glucose) were incubated at room temperature with varying concentrations of Leu-Leu-OMe. After a 15 minute exposure to this compound, the cells were washed, incubated for 2 hours at 37° C. and then assessed for the percentage of remaining viable cells which were stained by anti-MP or anti-NK monoclonal antibodies. Preincubation with greater than 25-50 micromolar Leu-Leu-OMe led to loss of NK cells. This concentration of Leu-Leu-OMe did not deplete MP from PBM but higher concentrations of Leu-Leu-OMe caused loss of MP. The data is FIG. 6 show these results.
Anti-MP monoclonal antibodies (63D3) and anti-NK monoclonal antibodies (leu 11b) were obtained from Becton Dickinson Monoclonal Center, Inc., Mountain View, CA. The antibody staining and Fluorescence Activated Cell Sorter (FACS) procedure was that of Rosenberg et al. (1981) (J. Immunol. V 126, p 1473). Data are expressed as percent of antibody staining in control cells (mean±SEM, n=4).
EXAMPLE 11
Effects of Leu-Leu-OMe on a Variety of Cell Types
While it was clear that a substantial percentage of lymphocytes remained viable following exposure to even 1 mM Leu-Leu-OMe, the finding that disparate cell types such as MP and NK were both susceptible to Leu-Leu-OMe mediated toxicity raised the possibility that this agent was a non-specific cell toxin. Therefore, the series of experiments depicted in FIG. 7 was performed to assess other cell types for evidence of toxicity following exposure to Leu-Leu-OMe.
To facilitate screening of multiple cell types for evidence of cell death following exposure to Leu-Leu-OMe, a 51 Cr release assay was devised. In preliminary experiments it was noted that 51 Cr release from MP-enriched populations exposed to varying concentrations of Leu-Leu-OMe correlated very closely with concentration-dependent loss of anti-MP antibody staining cells from PBM after similar incubation. Following brief exposures to Leu-Leu-OMe at room temperature, the loss of anti-MP antibody staining cells from PBM or the release of 51 Cr from MP-enriched populations was always detectable within a 30 to 60 minute period of culture at 37° C. and maximal effects were seen within 3 to 4 hours.
Therefore, 51 Cr release in a 4 hour assay was used in these experiments to assess toxicity from Leu-Leu-OMe. As shown in the first graph of FIG. 7, when the whole PBM population was exposed to varying concentrations of Leu-Leu-OMe, detectable 51 Cr release was observed after exposure to 25 to 50 micromolar Leu-Leu-OMe, but only upon exposure to greater than 100 micromolar Leu-Leu-OMe was the maximal achievable 51 Cr release from PBM observed. When MP-enriched adherent cells (AC) were similarly assessed, minimal 51 Cr release was observed after exposure to 25-50 micromolar Leu-Leu-OMe whereas upon incubation with higher concentrations of this agent, more 51 Cr release from AC was observed than with PBM. When nylon wool non-adherent lymphocytes (NAC) were assessed, small but significant 51 Cr release was observed with 25 to 50 micromolar Leu-Leu-OMe. When NAC were exposed to increasing concentrations of Leu-Leu-OMe, greater quantities of 51 Cr release were observed. N-SRBC positive cells showed a dose-dependent Leu-Leu-OMe induced 51 Cr release pattern indistinguishable from that of NAC. Since both antibody staining (FIG. 6) and functional studies (FIG. 4) have shown that 100 micromolar Leu-Leu-OMe causes maximal depletion of NK, this finding suggested that other lymphocytes were also susceptible to Leu-Leu-OMe toxicity at concentrations greater than 100 micromolar. When T4 enriched populations of T cells were assessed, however, it was clear that even 1000 micromolar Leu-Leu-OMe caused minimal 51 Cr release from this population. In contrast, when N-SRBC positive cells were depleted of OKT4 positive cells, the remaining T8-enriched population produced high levels of 51 Cr release following exposure to Leu-Leu-OMe.
When cell lines of myeloid or lymphoid origin were similarly assessed, selective toxicity of Leu-Leu-OMe was again observed. The human T cell leukemia line MoLT-4 demonstrated no detectable Leu-Leu-OMe toxicity over a broad concentration range. The human plasma cell lines HS-Sultan and the B lymphoblastoid line Daudi demonstrated no significant 51 Cr release or alteration in subsequent proliferaive rate (data not shown) after exposure to a broad range of Leu-Leu-OMe concentrations. When the susceptibility of EBV-transformed B cell lines or clones to this agent was assessed, no significant toxicity of less than 250 micromolar Leu-Leu-OMe was seen. However, with higher concentrations of Leu-Leu-OMe, a variable degree of toxicity was seen. Some EBV lines consistently displayed less than 20% 51 Cr release even after exposure to 1 mM Leu-Leu-OMe, while other lines produced 25-35% 51 Cr release after exposure to 250 micromolar Leu-Leu-OMe. In contrast, the human cell line U937 was susceptible to concentration-dependent Leu-Leu-OMe toxicity in a pattern indistinguishable from that of the peripheral blood MP with which this cell line shares many phenotypic and functional characteristics. After exposure to more than 250 micromolar Leu-Leu-OMe, extensive 51 Cr release was observed and no viable proliferating U937 cell could be detected (data not shown). Similarly, the erythroleukemia line K562 demonstrated no significant 51 Cr release or alteration in subsequent proliferative rate (date not shown) upon exposure to 100 micromolar or lower concentrations of Leu-Leu-OMe. With higher concentrations of Leu-Leu-OMe, modest amounts of 51 Cr release and partial loss of proliferative capacity were observed (data not shown). In contrast, a variety of cell types of non-lymphoid, non-myeloid origin including human umbilical vein endothelial cells, the human renal cell carcinoma line, Currie, the human epidermal carcinoma line, HEp-2, and human dermal fibroblasts demonstrated no significant Leu-Leu-OMe induced 51 Cr release. Furthermore, incubation of each of these non-lymphoid cell types with 500 micromolar Leu-Leu-OMe had no discernible effect on subsequent proliferative capacity (data not shown).
HS-Sultan, a human plasma cell line (Goldblum et al. (1973) Proc. Seventh Leucocyte Culture Conference, ed by Daguilland, Acad. Press N.Y. pp 15-28), Daudi, a B lymphoblastoid cell line (Klein et al. (1968) Cancer Res. V 28, p 1300), MoLT-4, an acute lymphoblastic T-cell leukemia line (Monowada et al. (1972) J. Nat'l. Canc. Inst. V 49, p 891), and U-937, a human monocyte-like cell line (Koren et al. (1979) Nature V 279, p 891) were obtained from the American Type Culture Collection, Rockville, MD. These lines as well as HEp-2 a human epidermoid carcinoma line (a generous gift of Dr. R. Sontheimer, UTHSCD); Currie, a human renal cell carcinoma line (a generous gift of Dr. M. Prager, UTHSCD); and K562, a human erythroleukemia line (a generous gift of Dr. M. Bennett, UTHSCD) were maintained in culture in medium RMPI supplemented with 10% FBS. Human dermal fibroblasts (a generous gift of Dr. T. Geppert, UTHSCD) were serially passaged in culture as well while human umbilical vein endothelial cells (a generous gift of Dr. A. Johnson, UTHSCD) were used after one subculture. Epstein Barr virus (EBV) transformed B lymphoblastoid cell lines JM.6 and SM.4 (kindly provided by Dr. J. Moreno, UTHSCD) and cloned EBV transformed B cell lines SDL-G2 and D8-219 (a generous gift of Drs. L. Stein and M. Dosch, Hospital for Sick Children, Toronto, Canada) were maintained in culture in medium RPMI supplemented with 10% FBS.
In some experiments, toxicity of Leu-Leu-OMe for a variety of cell populations was assessed by 51 Cr release. In assays where cells obtained from suspension culture were to be used, cells were labeled with Na 2 51 CrO 4 (ICN, Plainview, NY) for 60-90 minutes at 37° C. and then washed three times. Cells were then suspended in PBS (2.5×10 6 /ml) and incubated in microtiter plates, 50 microL/well with indicated concentrations of Leu-Leu-OMe for 15 minutes at room temperature. In assays where cells were obtained from monolayer cultures, microtiter wells were seeded with cells (5×10 4 /well) and cultured for 24 hours at 37° C. Cells were then labeled with Na 2 51 CrO 4 while in adherent culture. Following 51 Cr labeling, wells were thoroughly washed and varying concentrations of Leu-Leu-OMe added in 50 microL PBS and the plates incubated for 15 minutes at room temperature.
Following such initial serum-free incubations, 200 microL/well of medium RPMI containing 10% FBS were added and the plates incubated for another 4 hours prior to removal of 100 microliters of supernatant. Radioactivity in the supernatant was measured in an auto-gamma scintillation spectrometer (Packard Instrument Co., Downers Grove, IL). The percent specific release was calculated from the formula: ##EQU2## in which maximal release refers to cpm obtained in wells containing 50% lysing agent (American Scientific Products, McGraw Park, IL) and spontaneous release refers to cpm released by cells incubated in control medium in the absence of Leu-Leu-OMe or the lysing agent. Only experiments in which spontaneous release was 25% were used for subsequent data interpretation.
While the MP-like tumor line U937 was virtually identical to MP in susceptibility to Leu-Leu-OMe, none of the non-lymphoid, non-myeloid cell lines tested demonstrated such susceptibility to Leu-Leu-OMe mediated toxicity.
The current example demonstrates that at concentrations 10 to 20 fold greater than those at which cytotoxic cells are ablated, Leu-Leu-OMe does have some minimal toxicity for certain non-cytotoxic lymphoid cells such as EBV transformed B cells and K562 cells. Yet, while it is impossible to exhaustively exclude the possibility that certain non-cytotoxic cells might also be equally sensitive to Leu-Leu-OMe-mediated toxicity, at present the ability to function as a mediator of cell mediated cytotoxicity is the one unifying characteristic of the cell types which are rapidly killed by exposur to Leu-Leu-OMe.
In developing the data expressed in FIG. 7, cells (2.5×10 6 /ml) were exposed to the indicated concentrations of Leu-Leu-OMe for 15 minutes at room temperature, then specific 51 Cr release during the next four hours was assessed. Data for the EBV transformed lines JM.6, SDLG2, D8-219, and SM.4, respectively, are shown in order from top to bottom.
EXAMPLE 12
Relative Sensitivity of CTL and NK to Leu-Leu-OMe
Experiments were also designed to assess the relative sensitivity of NK and CTL to Leu-Leu-OMe. In the studies detailed in FIGS. 8 and 9, cytotoxicity assays were performed over a broad range of E:T ratios and units of lytic activity arising from equal numbers of responding lymphocytes were calculated and compared. As shown in FIG. 8, both spontaneous NK and precursors of activated NK were totally eliminated by exposure to 100 micromolar Leu-Leu-OMe while CTL precursors, though diminished, were generally still present at greater than 50% of control levels. Only after exposure to greater than 250 micromolar Leu-Leu-OMe were all CTL precursors eliminated.
FIG. 8 shows that incubation with Leu-Leu-OMe eliminates precursors of cytotoxic T lymphocytes (CTL) and activated NK-like cells (AcNK). Non-adherent lymphocytes (2.5×10 6 /ml) were incubated with the indicated concentrations of Leu-Leu-OMe for 15 minutes. Cells were then washed and either placed in mixed lymphocyte culture or assayed for specific lysis of K562 cells (NK). After 6 day MLC, cells were assayed for specific lysis of allogeneic stimulator lymphoblasts (CTL) or K562 (AcNK). Data are expressed as percent of control lytic units (mean +SEM, n=6).
When the elimination of CTL and activated NK precursors by Leu-Leu-OMe was compared to that of spontaneous NK, the mean Leu-Leu-OMe concentration required to diminish lytic activity by 75% was significantly greater for elimination of CTL precursors (123±25 micromolar) than for elimination of precursors of activated NK (50±5 micromolar, p 0.05). Both values were also higher than the mean concentration of Leu-Leu-OMe required to diminish spontaneous NK lytic activity by 75% (35 micromolar ±4 micromolar). FIG. 9 shows that, following activation, CTL and AcNK became identical in sensitivity to Leu-Leu-OMe. After 6 day MLC, cells were incubated for 15 minutes with the indicated concentrations of Leu-Leu-OMe, then assayed for CTL or AcNK activity as for FIG. 8. Thus, only after MLC activation did CTL display a sensitivity to Leu-Leu-OMe toxicity that was equal to that of NK cells.
Changes may be made in the construction, operation and arrangement of the various elements, steps and procedures described herein without departing from the concept and scope of the invention as defined in the following claims. | An alkyl ester of dipeptide consisting essentially of natural or synthetic L-amino acids with hydrophobic side chains. Preferable amino acids are leucine, phenylalanine valine, isoleucine, alanine, proline, glycine or aspartic acid beta methyl ester. Preferable dipeptides are L leucyl L-leucine, L-leucyl L-phenylalanine, L-valyl L-phenylalanine, L-leucyl L-isoleucine, L-phenylalanyl L-phenylalanine, L-valyl L-leucine, L-leucyl L-alanine, L-valyl L-valine, L-phenylalanyl L leucine, L prolyl L-leucine, L-leucyl L-valine, L-phenylalanyl L-valine, L glycyl L-leucine, L-leucyl L-glycine or L-aspartyl beta methyl ester L-phenylalanine. Most preferable dipeptides are L-leucyl L-leucine, L-leucyl L-phenylalanine, L-valyl L-phenylalanine, L-phenylalanyl L-leucine, L-leucyl L-isoleucine L-phenylalanyl L-phenylalanine and L-valyl L-leucine.
The alkyl ester of the dipeptide is most preferably a methyl ester and may also be an ethyl ester or alkyl of up to about four carbon atoms such as propyl, isopropyl, butyl or isobutyl.
These alkyl esters of dipeptides consisting essentially of amino acids with hydrophobic side chains may be used to deplete cytotoxic T-lymphocytes or natural killer cells from organisms, cell populations or tissues. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application 60/437,814 having a filing date of Jan. 3, 2003, the entire contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention generally relates to a flexible safety edge guard device. Particularly, this invention relates to a safety edge guard that is fastened to a moveable platform. The safety guard provides the platform with a soft bumper that compresses when it contacts an interfering object in its travel path.
[0003] Vertical lift tables, tilt tables, and other equipment having moveable platforms are widely known. This equipment is used in various industrial applications such as in the handling of materials and packages and in other assembly line operations. The vertical lift tables help provide a safe and healthy work environment. The lift tables help prevent back injuries caused by a person having to constantly bend over to pick-up packages. In general, vertical lift tables include a moveable platform that can be vertically raised and lowered by a power means such as a hydraulic telescopic mast unit or scissor lift. Typically, the moveable platform has steel edges. The lift tables can have a manual or electric motor power supply unit. Scissor lift tables, which have one or more sets of pantograph leg sections that are used to raise and lower the platform, are common. The pantograph leg sections support and stabilize the platform in its raised position. Vertical lift tables can be mounted on a base or placed directly on a supportive surface such as a floor. It is important that a person uses care and follows safety precautions while operating lift tables. Particularly, a person needs to be careful that he or she does not pinch a finger, toe, or other body part under the steel platform as it is lowered to the supporting base or floor.
[0004] Various safety guard devices for lift tables and other equipment having moveable platforms have been proposed. Safety guards for garage doors have also been developed.
[0005] For instance, Richards, U.S. Pat. 3,920,101 discloses a protective device which is fastened to the periphery of a vertically moving platform. The platform moves into and is received in a recessed area formed in a floor. The protective device comprises a rubber band that extends from the platform so that it will brush against an operator's body when he or she is too close to the descending platform. According to the '101 Patent, the rubber band presses against the individual's leg as the platform descends and this warns the individual that he or she is in a danger area and must move back.
[0006] Clarke et al., U.S. Pat. 4,091,906 discloses a collapsible electric foot-toe guard which is used with a loading platform. The collapsible foot-toe guard protects against injuries. The foot-toe guard includes a contact plate which moveably engages a base support plate by a hinge means. The contact plate folds toward the support plate upon engaging an interfering obstacle. According to the '906 Patent, an electric switch circuit can be included so that the folding movement of the contact plate deactivates the electrically-powered descending movement of the platform.
[0007] Ziegler, U.S. Pat. 4,269,253 discloses a safety guard rubber-like strip for roller-type garage doors having horizontal panels which are hinged together. The flexible safety guard strip is attached to the upper outside surface of each door panel so that it extends upwardly. The safety guard strip covers and shields the gap between the hinged panels of the door to protect the door operator from injury. In this manner, the safety guard strip helps prevent an operator from pinching his or her fingers between the hinged panels.
[0008] Although some conventional safety guard devices can protect against injuries from some mechanical devices, there is a need for an improved safety guard device. The improved safety guard should be capable of being easily mounted onto a vertically moveable platform such as the platform used for a lift or tilt table. Furthermore, the improved safety guard should compress upon contacting an interfering object in its travel path. The present invention provides such a safety guard device. These and other objects, features, and advantages of this invention are evident from the following description and attached figures.
SUMMARY OF THE INVENTION
[0009] The present invention relates to an elongated, flexible safety edge guard for use with moveable platforms. The platform has a support frame and is capable of moving in ascending and descending directions. In one embodiment, the safety guard comprises: (i) a substantially “U-shaped” upper portion, and (ii) a lower portion that extends from the U-shaped upper portion. The U-shaped upper portion has opposing side wall segments that are connected together. The side wall segments define an open space therebetween for receiving the support frame of the platform. The safety guard is tightly fastened to the platform by sliding the support frame into the U-shaped upper portion. The support frame can be constructed so that it includes an angle support bracket mounted to each side of the platform. The angle side support bracket can include a vertically extending arm that is inserted into the U-shaped upper portion of the safety guard.
[0010] In one embodiment, the lower portion of the safety guard has opposing side wall segments that are connected together to form a looped structure. The side wall segments define a linear channel therebetween. In another embodiment, the lower portion of the safety guard has a substantially “J-shaped” structure. The J-shaped lower portion includes a vertically extending segment and a hook segment. The flexible safety guard compresses upon contacting an object lying in its path as the platform moves in a descending direction.
[0011] In other instances, the safety edge guard does not include an U-shaped upper portion. For example, the safety guard can include a vertically extending segment and a hook segment to form a substantially J-shaped structure along its entire length. in another example, the safety guard can include a vertically extending segment having one end and an opposing end with a looped structure.
[0012] The safety guard of this invention can be made from any suitable flexible plastic material such as a polyvinyl chloride. The safety guard can be produced by a plastic molding operation. The mold can provide the safety guard with side wall segments having a wavy-like structure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The novel features that are characteristic of the present invention are set forth in the appended claims. However, the preferred embodiments of the invention, together with further objects and attendant advantages, are best understood by reference to the following detailed description taken in connection with the accompanying drawings in which:
[0014] [0014]FIG. 1 is a side perspective view of one embodiment of the safety guard article of the present invention, wherein the safety guard has a “U-shaped” upper portion and a lower portion containing a linear channel;
[0015] [0015]FIG. 2 is a cross-sectional view through Line 2 - 2 of FIG. 1;
[0016] [0016]FIG. 3 is a side perspective view of another embodiment of the safety guard article of the present invention, wherein the safety guard has a “U-shaped” upper portion and a “J-shaped” lower portion;
[0017] [0017]FIG. 4 is a cross-sectional view through Line 4 - 4 of FIG. 3;
[0018] [0018]FIG. 5 is a side perspective view of a scissor-lift table equipped with a safety guard article of the present invention;
[0019] [0019]FIG. 6 is a partially-exploded view showing the safety guard article of the present invention fastened to an angle side support bracket on the under surface of a lift table-platform;
[0020] [0020]FIG. 7 is a side perspective view of one embodiment of the safety guard article of the present invention, wherein the safety guard has a “J-shaped” structure; and
[0021] [0021]FIG. 8 is a side perspective view of one embodiment of the safety guard article of the present invention, wherein the safety guard has a “looped” structure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] Referring to FIG. 1, one embodiment of the safety edge guard 2 of this invention is shown. The elongated, safety edge guard 2 comprises a substantially “U-shaped” upper portion generally indicated at 4 having two upwardly projecting side wall segments 6 and 8 that are connected by an integrated cross-segment 10 . The cut-out portion of the “U” forms an upper linear channel 12 that extends along the length of the safety guard 2 . In FIG. 1, the safety guard 2 further comprises a lower portion generally indicated at 14 having two side wall segments 16 and 18 surrounding a lower linear channel 20 that extends in parallel to the upper linear channel 12 . The safety guard 2 is an unitary structure, wherein lower portion 14 extends from the U-shaped upper portion 4 . FIG. 2 shows a cross-sectional end view of the safety guard 2 .
[0023] The safety guard 2 can be of any size, and it is recognized that the dimensions can be modified based on the size of the platform which will be fitted with the safety guard. In one embodiment, the overall height of the safety guard 2 can be about 3.5 inches. Particularly, the side wall segment 6 can be about 2 inches and the side wall segment 16 can be about 1.5 inches. The inside diameter of the upper linear channel 12 can be about 0.25 inches. The thickness of the side wall segment 8 can be about 0.2 inches, and the thickness of the side wall segment 18 can be about 0.13 inches.
[0024] The safety guard 2 can be made from any suitable resilient material such as an elastomer, soft vinyl, or other plastic provided that the material bends and deforms sufficiently when striking an interfering object as described further below. For example, the safety guard 2 can be made from polyolefins, polyvinyl chlorides, polyurethanes, polyamides, polyesters, acrylics, polystyrenes, and elastomer rubbers such as styrene-butadiene copolymers, silicones, and polychloroprene. The polymeric materials can be molded into a safety guard 2 having a rubber-like elasticity and texture. The safety guard 2 can be made using any suitable manufacturing technology including extrusion, injection-molding, blow-molding, casting, vacuum molding, and the like. A molding process can be used to mold a safety guard 2 having a molded, unitary structure. The upper portion 4 and lower portion 14 of the safety guard 2 are connected integrally together. Also, the safety guard 2 can be molded so that at least a portion of the guard has an undulating structure as shown in FIGS. 1 and 2. Particularly, the side wall segments 6 and 16 in the safety guard 2 can have a wave-like design characterized by convex wave peaks (A, B, C, and D) in FIGS. 1 and 2. It is understood that the molded wave-like structure of the side wall segments 6 and 16 is only one of many possible structures and is shown for illustration purposes only. For example, the side wall segments 6 and 16 alternatively may have a generally flat shape.
[0025] Another embodiment of the safety edge guard of this invention is shown in FIG. 3. The elongated, safety edge guard shown in FIG. 3 is generally indicated at 2 a . The U-shaped upper portion 4 a of the safety guard 2 a is similar to the U-shaped upper portion 4 of the safety guard 2 shown in FIG. 1. Particularly, the upper portion 4 a includes two side wall segments 6 a and 8 a that are connected by a cross-segment 10 a . The U-shaped upper portion 4 a includes an upper linear channel 12 a . However, in contrast to the safety guard 2 shown in FIG. 1, the safety guard 2 a comprises a substantially “J-shaped” lower portion generally indicated at 22 . By the term, “J-shaped” as used herein, it is meant a forward facing “J” and the inverted, mirror image of “J”. The “J-shaped” lower portion 22 includes a vertically extending segment 23 and a hook segment 24 . FIG. 4 shows a cross-sectional view of the safety guard 2 a.
[0026] The flexible safety guards 2 and 2 a can be fastened to a vertical lift table 26 as shown in FIG. 5. Vertical lift tables 26 are known in the industry and used in various industrial applications such as a platform for packaging finished products or feeding raw materials to processing equipment. The vertical lift table 26 show in FIG. 5 is powered by a motorized hydraulic pump 27 , but other power supply means can be used. The safety guards 2 and 2 a provide a soft, flexible safety bumper to the vertical lift table 26 and can protect a person operating the table 26 against serious injury. It is also understood that the safety guards 2 and 2 a can be fastened to other equipment having a platform that moves in ascending and descending directions in accordance with this invention. For example, the safety guards 2 and 2 a can be fastened to tilt tables. Also, in FIG. 5, the safety guard is designated as 2 for illustration purposes only, and the fastening of safety guard 2 to the lift table 26 is described in further detail below. But, it is understood that safety guard 2 a can be fastened to the vertical lift table 26 in a similar manner.
[0027] More particularly, a vertical lift table 26 having a set of scissor-like legs 28 and a moveable platform 30 is shown in FIG. 5. The lift table 26 includes a base 32 which is placed on a floor or other supporting surface. The platform 30 has a rectangular shape with one platform end 34 and an opposing end 36 connected by sides 38 and 40 . Typically, the platform 30 is made of steel and has a width of about twenty-four (24), thirty-six (36), or forty-eight (48) inches. The platform 30 is shown having a rectangular shape in FIG. 5 for illustration purposes only. However, it is understood that the platform 30 can be of any suitable design; for example, the platform 30 can have a square or circular shape.
[0028] The safety edge guard 2 can be fastened to the platform 30 by means of a support frame 42 as shown in FIG. 6. The support frame 42 provides the platform 30 with mechanical support and a means for attaching the safety edge guard 2 to the platform. In FIG. 6, the support frame 42 includes angle side support brackets 44 , each having an upper support arm 46 that extends horizontally and a lower support arm 48 that extends vertically. The angle side support brackets 44 are mounted to the under surface 50 of the platform 30 . The top surface of the platform is indicated at 52 . The support frame 42 further includes end support brackets 54 which are located at each end of the frame 42 . The angle side support brackets 44 and end support brackets 54 can be mounted to the underside 50 of the platform 30 using bolts, screws, or other suitable fastening means. It is recognized that other support frames for the platform can be used in accordance with this invention. The support frame may be an integral part of the lift/tilt table or may be installed onto the table as an additional component to provide a means for fastening the safety edge guard.
[0029] The safety guard 2 can be fastened to the platform 30 by mounting the safety guard 2 onto the support frame 42 in the following manner. Particularly, the U-shaped upper portion 4 of the safety guard 2 receives the lower support arms 48 of the angle side support brackets 44 . The lower support arm 48 is inserted into the linear channel 12 of the “U-shaped” upper portion 4 . Thus, the safety guard 2 is tightly fastened to the platform 30 . The soft, elastic nature of the safety guard 2 means that the safety guard can be manipulated easily to fit around the lower support arm 48 of the angle side support bracket 44 . The flexible safety guard 2 conforms snugly around the lower support arm 48 and thus tightly secures the safety guard 2 to the platform 30 . As shown in FIG. 6, the safety guard can be wrapped around the corners of the support frame 42 and fastened to the end support bracket 54 by adhesives, bolts, or other suitable fasteners.
[0030] The safety guard 2 helps prevent injuries to a person operating the vertical lift table 26 . As discussed above, the safety guard 2 can extend around the entire perimeter of the platform 30 . The safety guard 2 provides a comprehensive safety bumper skirt when fastened to all of the edges of the platform 30 . In operation, the flexible safety guard 2 compresses when it strikes an interfering object lying in its travel path. The safety guard 2 acts as a warning signal or bumper to soften the blow of the platform 30 against the object. For instance, if the platform 30 descends accidentally while an operator is working with the table 26 , the flexible safety guard 2 initially contacts the operator's hands or feet. This contact gives the operator an opportunity to move quickly away from the platform 30 and avoid injury. If the operator is unable to move away from the descending platform 30 , and the platform continues descending to its fully lowered position, the flexible safety guard 2 can cushion the blow.
[0031] In still another embodiment, the safety edge guard does not include the “U-shaped” upper portion 4 or 4 a as shown in FIGS. 1 - 6 . Rather, a safety guard 60 having a “J-shaped” structure as shown in FIG. 7, or a safety guard 70 having a “looped structure” as shown in FIG. 8 can be made in accordance with this invention. In FIG. 7, the elongated, safety edge guard 60 is characterized by having a vertically extending segment 62 and a hook segment 64 . In FIG. 8, the elongated, safety edge guard 70 includes a vertically extending segment having one end 72 and an opposing end 74 with a looped structure 76 . The looped structure 76 defines a linear channel 78 that extends along the length of the safety guard 70 . The safety edge guard 60 or 70 can be fastened to a support frame of a moveable platform by adhesives, screws, bolts, or other suitable fasteners.
[0032] The safety edge guards 60 and 70 operate in a manner similar to the safety edge guards 2 and 2 a described above. The safety edge guards 60 and 70 bend and deform upon striking an interfering object such as a human limb lying in the path of the descending platform 30 . The compressing action of the safety guard 60 helps cushion the blow against the interfering object and can protect against serious bodily injury. Particularly, the hook segment 64 of the flexible safety guard 60 contacts the foreign object initially and this force causes the safety guard 60 to compress. With respect to the flexible safety guard 70 , the looped structure 76 makes initial contact with the foreign object and triggers the compression of the safety guard 70 . The safety guards 60 and 70 bend and absorb the striking force against the object.
[0033] It is appreciated by those skilled in the art that various other changes and modifications can be made to the illustrated embodiments and description herein without departing from the spirit of the present invention. All such modifications and changes are intended to be covered by the appended claims. | An elongated, flexible safety guard for use with moveable platforms is provided. The platform, which the safety guard is mounted thereto, has a support frame and is capable of moving in ascending and descending directions. In one embodiment, the safety guard comprises: (i) a substantially “U-shaped” upper portion, and (ii) a lower portion that extends from the U-shaped upper portion. The U-shaped upper portion has opposing side wall segments that are connected together. The side wall segments define an open space therebetween for receiving the support frame of the platform. In one embodiment, the lower portion of the safety guard has a “J-shaped” configuration. | 4 |
RELATED APPLICATION DATA
This application is a division of U.S. patent application Ser. No. 10/112,721 filed Apr. 2, 2002, now U.S. Pat. No. 6,512,135 which is a division of U.S. patent application Ser. No. 09/888,593 filed Jun. 26, 2001, now U.S. Pat. No. 6,407,285, which is a division of U.S. patent application Ser. No. 09/300,835 filed Apr. 28, 1999, now U.S. Pat. No. 6,303,786, issued Oct. 16, 2001, which is a division of U.S. patent application Ser. No. 08/923,943, filed Sep. 5, 1997, now U.S. Pat. No. 5,962,725, issued Oct. 5, 1999, which claims benefit of priority under 35 U.S.C. §119 to U.S. Provisional Patent Application No. 60/025,515 filed Sep. 5, 1996, the disclosures of each of which are incorporated herein by reference.
This application claims priority benefits under 35 U.S.C. § 119 based on U.S. Provisional Patent Appln. Ser. No. 60/025,517, filed Sept. 5, 1996. This provisional application is entirely incorporated herein by reference. Additionally, this application relates to the following U.S. patent applications:
U.S. Patent Appln. No.
Filing Date
08/133,543
Oct. 7, 1993
08/133,696
Oct. 7, 1993
08/190,764
Feb. 2, 1994
08/481,833
Jun. 7, 1995
08/708,411
Sep. 5, 1996
Each of these U.S. patent applications also is entirely incorporated herein by reference.
INTRODUCTION
Treatment of HIV-infected individuals is one of the most pressing biomedical problems of recent times. A promising new therapy has emerged as an important method for preventing or inhibiting the rapid proliferation of the virus in human tissue. HIV-protease inhibitors block a key enzymatic pathway in the virus resulting in substantially decreased viral loads, which slows the steady decay of the immune system and its resulting deleterious effects on human health. The HIV-protease inhibitor nelfinavir mesylate of formula 7
has been shown to be an effective treatment for HIV-infected individuals. Nelfinavir mesylate is disclosed in U.S. Pat. No. 5,484,926, issued Jan. 16, 1996. This patent is entirely incorporated by reference into this patent application.
The present inventors have discovered useful intermediate compounds that can be used in several reaction schemes to make nelfinavir mesylate. The present inventors also have discovered new methods for making nelfinavir mesylate from the free base nelfinavir of formula 4:
The nelfinavir free base also is disclosed in U.S. Pat. No. 5,484,926.
SUMMARY OF THE INVENTION
It is an object of this invention to provide compounds and intermediates useful for making HIV-protease inhibitors and methods of making HIV-protease inhibitors. Such inhibitors are useful for treating HIV-infected individuals.
In a first aspect, the invention relates to compounds of formula 3:
wherein R 1 is alkyl; cycloalkyl; heterocycloalkyl; aryl; heteroaryl; or a group of formula 8
wherein R 2 is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, or O—R 6 ,
wherein R 6 is an alkyl group, an aralkyl group, or an aryl group;
or further wherein R 1 is a group of formula 9
wherein each R 3 is independently an alkyl group, a cydoalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group;
or further wherein R 1 is a group of formula 10
wherein R 4 and each R 5 independently are an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group; and
X is OH; OR 7 , wherein R 7 is alkyl or aryl; halogen; pseudohalogen; OSO 2 R 8 , wherein R 8 is alkyl or aryl; heteroaryl bonded through the heteroatom; or N-hydroxyheterocyclic bonded through the oxygen, with the proviso that when R 1 is —CH 3 , X cannot be —OCH 3 or —OH, and when R 1 is CH 3 C(O)—, X cannot be —OH;
or a pharmaceutically acceptable salt or solvate thereof.
In various preferred embodiments of the invention, R 1 is —C(O)CH 3 and/or X is a halogen, preferably, Cl.
In another aspect, the invention relates to compounds of formula 2:
wherein R 1 is a C 2 to C 8 alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, a heteroaryl group, or a group of formula 8
wherein R 2 is a C 2 to C 8 alkyl group, a cycloalkyl group, a heterocycloalkyl group, or O—R 6 , wherein R 6 is an alkyl group, an aralkyl group, or an aryl group;
or further wherein R 1 is a group of formula 9
wherein each R 3 independently is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group;
or further wherein R 1 is a group of formula 10
wherein R 4 and each R 5 independently are an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group;
or a pharmaceutically acceptable salt or solvate thereof.
This invention further relates to methods for making the compounds of formulae 2 and 3. In a method for making a compound of formula 2:
a compound according to formula 1, shown below,
is reacted under suitable and sufficient conditions to add an R 1 protecting group and form a compound of formula 2. In this instance, R 1 is a C 2 to C 8 alkyl group; a cycloalkyl group; a heterocycloalkyl group; an aryl group; a heteroaryl group; or a group of formula 8
wherein R 2 is a C 2 to C 8 alkyl group, a cycloalkyl group, a heterocycloalkyl group, or O—R 6 , wherein R 6 is an alkyl group, an aralkyl group, or an aryl group;
or R 1 is a group of formula 9
wherein each R 3 is independently an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group;
or R 1 is a group of formula 10
wherein R 4 and each R 5 independently are an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group.
This invention includes a method of making a compound according to formula 3
This method includes adding, under suitable and sufficient conditions, a suitable protecting group R 1 and a leaving group X to a compound of formula 1
In this instance, R 1 is alkyl, cycloalkyl; heterocycloalkyl; aryl; heteroaryl; or a group of formula 8
wherein R 2 is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, or O—R 6 , wherein R 6 is an alkyl group, an aralkyl group, or an aryl group;
or R 1 is a group of formula 9
wherein each R 3 is independently an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group;
or further wherein R 1 is a group of formula 10
wherein R 4 and each R 5 independently are an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group; and
X is OH; OR 7 , wherein R 7 , is alkyl or aryl; halogen; pseudohalogen; OSO 2 R 8 , wherein R 8 is alkyl or aryl; heteroaryl bonded through the heteroatom; or N-hydroxyheterocyclic bonded through the oxygen, with the proviso that when R 1 is —CH 3 , X cannot be —OCH 3 or —OH, and when R 1 is CH 3 C(O)—, X cannot be —OH. As noted above, in certain embodiments, R 1 is —C(O)CH 3 and/or X is a halogen, preferably, Cl.
A compound according to formula 3, as defined above, also can be made from a compound of formula 2. The reaction proceeds by adding a suitable leaving group X to the compound of formula 2. In this instance, formula 2 is as defined below:
wherein R 1 is alkyl; cycloalkyl; heterocycloalkyl; aryl; heteroaryl; or a group of formula 8
wherein R 2 is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, or O—R 6 , wherein R 6 is an alkyl group, an aralkyl group, or an aryl group;
or further wherein R 1 is a group of formula 9
wherein each R 3 is independently an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group;
or further wherein R 1 is a group of formula 10
wherein R 4 and each R 5 independently are an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group. Additionally, in this instance, X is defined as OH; OR 7 , wherein R 7 is alkyl or aryl; halogen; pseudohalogen; OSO 2 R 8 , wherein R 8 is alkyl or aryl; heteroaryl bonded through the heteroatom; or N-hydroxyheterocyclic bonded through the oxygen. In this method, when R 1 is —CH 3 , X cannot be —OCH 3 or —OH, and when R 1 is CH 3 C(O)—, X cannot be —OH.
This invention further relates to methods for making HIV-protease inhibitors. One HIV-protease inhibitor produced by a method according to this invention is a compound of formula 4, illustrated below:
In this method, a compound of formula 3
wherein R 1 is alkyl; cycloalkyl; heterocycloalkyl; aryl; heteroaryl; or a group of formula 8
wherein R 2 is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, or O—R 6 , wherein R 6 is an alkyl group, an aralkyl group, or an aryl group;
or further wherein R 1 is a group of formula 9
wherein each R 3 independently is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group;
or further wherein R 1 is a group of formula 10
wherein R 4 and each R 5 independently are an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group; and
X is OH; OR 7 , wherein R 7 is alkyl or aryl; halogen; pseudohalogen; OSO 2 R 8 , wherein R 8 is alkyl or aryl; heteroaryl bonded through the heteroatom; or N-hydroxyheterocyclic bonded through the oxygen,
is reacted under suitable and sufficient conditions to form the compound of formula 4. Again, for one preferred embodiment of this process, the variable R 1 represents —C(O)CH 3 and/or the variable X represents Cl.
The compound according to formula 4, identified above, also can be prepared by deprotecting a compound of formula 5
and reacting with it, under sufficient conditions, a compound of formula 3. In this instance, the compound according to formula 3 is
wherein R 1 is alkyl; cycloalkyl; heterocycloalkyl; aryl; heteroaryl; or a group of formula 8
wherein R 2 is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, or O—R 6 , wherein R 6 is an alkyl group, an aralkyl group, or an aryl group;
or further wherein R 1 is a group of formula 9
wherein each R 3 independently is an alkyl group, a cydoalkyl group, a heterocydoalkyl group, an aryl group, or a heteroaryl group;
or further wherein R 1 is a group of formula 10
wherein R 4 and each R 5 independently are an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group; and
X is OH; OR 7 , wherein R 7 is alkyl or aryl; halogen; pseudohalogen;. OSO 2 R 8 , wherein R 1 is alkyl or aryl; heteroaryl bonded through the heteroatom; or N-hydroxyheterocyclic bonded through the oxygen.
In another embodiment of this invention, a compound of formula 4, as identified above, can be prepared by combining a compound of formula 3:
wherein R 1 is alkyl; cycloalkyl; heterocycloalkyl; aryl; heteroaryl; or a group of formula 8
wherein R 2 is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, or O—R 6 , wherein R 6 is an alkyl group, an aralkyl group, or an aryl group;
or further wherein R 1 is a group of formula 9
wherein each R 3 independently is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group;
or further wherein R 1 is a group of formula 10
wherein R 4 and each R 5 independently are an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group; and
X is OH; OR 7 , wherein R 7 is alkyl or aryl; halogen; pseudohalogen; OSO 2 R 8 , wherein R 8 is alkyl or aryl; heteroaryl bonded through the heteroatom; or N-hydroxyheterocyclic bonded through the oxygen,
with a compound of formula 6
under conditions sufficient and suitable to obtain the compound of formula 4.
This invention further relates to methods of making a compound of formula 7. In one embodiment, the compound of formula 7
is produced by converting a compound of formula 4
under sufficient and suitable conditions to the compound of formula 7. In this method, the conversion of the compound of formula 4 to the compound of formula 7 takes place by:
(a) contacting the compound of formula 4 with an organic solvent;
(b) contacting the compound of formula 4 with methanesulfonic acid under conditions sufficient to form a compound of formula 7; and
(c) spray drying the compound of formula 7. In a more specific embodiment of this method, the organic solvent is ethanol.
In another method for making a compound of formula 7 from a compound of formula 4, the following procedure is followed:
(a) the compound of formula 4, a suitable solvent, and methanesulfonic acid are combined to form the compound of formula 7, the compound of formula 7 being dissolved in solution;
(b) a first antisolvent is added to the solution containing the compound of formula 7;
(c) the compound of formula 7 and the first antisolvent are agitated together to form a product having a solid phase and a liquid phase; and
(d) the product is filtered and washed with a second antisolvent, the second antisolvent being the same as or different from the first antisolvent, to obtain a solid final product according to formula 7. After the solid final product is washed, it can be dred by any appropriate method or means. Tetrahydrofuran can be used as the solvent, and diethylether can be used as at least one antisolvent, preferably at least the first antisolvent.
This invention also relates to a method of making a compound according to formula 4 (as defined above) from a compound according to formula 2. In this method, a compound according to formula 2 is reacted under sufficient and suitable conditions to form the compound of formula 4. In this instance, the compound of formula 2 is defined as follows:
wherein R 1 is alkyl; cycloalkyl; heterocycloalkyl; aryl; heteroaryl; a group of formula 8
wherein R 2 is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, or O—R 6 , wherein R 6 is an alkyl group, an aralkyl group, or an aryl group;
or further wherein R 1 is a group of formula 9
wherein each R 3 independently is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group;
or further wherein R 1 is a group of formula 10
wherein R 4 and each R 5 independently are an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group.
Yet another embodiment of this invention relates to a method of making a compound of formula 7, defined above. In this method, a compound according to formula 5
is deprotected. Then, the deprotected compound of formula 5 is reacted, under sufficient and suitable conditions, with a compound of formula 3. Formula 3, in this instance, is defined as follows:
wherein R 1 is alkyl; cycloalkyl; heterocycloalkyl; aryl; heteroaryl; or a group of formula 8
wherein R 2 is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, or O—R 6 , wherein R 6 is an alkyl group, an aralkyl group, or an aryl group;
or further wherein R 1 is a group of formula 9
wherein each R 3 independently is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group;
or further wherein R 1 is a group of formula 10
wherein R 4 and each R 5 independently are an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group; and
X is OH; OR 7 , wherein R 7 is alkyl or aryl; halogen; pseudohalogen; OSO 2 R 8 , wherein R 8 is alkyl or aryl; heteroaryl bonded through the heteroatom; or N-hydroxyheterocyclic bonded through the oxygen. The reaction of compounds 3 and 5 produces a compound of formula 4, described above. The compound according to formula 4 is then converted to the compound of formula 7, for example, by one of the methods described above.
DETAILED DESCRIPTION OF THE INVENTION
This invention relates to compounds and intermediates useful for making HIV-protease inhibitors, methods of making the compounds and intermediates, and methods of making HIV-protease inhibitors.
As mentioned above, one aspect of this invention relates to compounds that are useful (e.g., as starting materials or intermediates) for making HIV-protease inhibitors. One such group of compounds are identified in this application by formula 3, shown below:
wherein R 1 is alkyl; cycloalkyl; heterocycloalkyl; aryl; heteroaryl; a group of formula 8
wherein R 2 is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, O—R 6 (wherein R 6 is an alkyl group, an aralkyl group, or an aryl group); a group of formula 9
wherein each R 3 independently is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group; or a group of formula 10
wherein R 4 and each R 6 independently are an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group; and
X is OH; OR 7 (wherein R 7 is alkyl or aryl); halogen; pseudohalogen, including azide, cyanide, isocyanate and isothiocyanate; OSO 2 R 8 (wherein R 8 is alkyl or aryl); heteroaryl bonded through the heteroatom; or N-hydroxyheterocyclic, including hydroxysuccinimide or hydroxybenzotriazole ester, bonded through the oxygen, with the proviso that when R 1 is —CH 3 , X cannot be —OCH 3 or —OH, and when R 1 is CH 3 C(O)—, X cannot be —OH; and to pharmaceutically acceptable salts and solvates thereof. Preferably X is a halogen, particularly, Cl.
The present invention also is directed to novel compounds of formula 2
wherein R 1 is a C 2 to C 8 alkyl group; a cycloalkyl group; a heterocycloalkyl group; an aryl group; a heteroaryl group; a group of formula 8
wherein R 2 is a C 2 to C 8 alkyl group, a cycloalkyl group, a heterocycloalkyl group, O—R 6 (wherein R 6 is an alkyl group, an aralkyl group, or an aryl group); a group of formula 9
wherein each R 3 independently is an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group; or a group of formula 10
wherein R 4 and each R 5 independently are an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, or a heteroaryl group; and to pharmaceutically acceptable salts and solvates thereof.
When R 1 is a group of formula 8 where R 2 is alkyl, R 1 can be, for example, acetate, propanoate, butanoate, pivaloate, or any related alkyl ester or mixed carbonate with a group such as benzyl . Other examples of R 1 groups where R 1 is a group of formula 8 include esters of aromatic and heteroaromatic acids, such as benzoate, substituted benzoate, 1- or 2-naphthoate or substituted 1- or 2-naphthoate, or a substituted 5- or 6-membered heteroaromatic ester. Examples of R 1 groups where R 1 is an alkyl include methyl, substituted methyl, ethyl, propyl, and butyl. Examples of R 1 when R 1 is a silyl ether of formula 9 include trimethylsilyl, t-butyldimethylsilyl, triisopropylsilyl, triphenylsilyl, and silyl ethers where the alkyl groups R 3 are some combination of simple alkyl and aryl groups. Examples of R 1 where R 1 is part of an acetal or ketal of formula 10 include acetonide, cyclohexylidene ketal, benzylidene acetal, 2-methoxyethoxyethyl acetal, and related acetals and ketals where R 4 and R 5 are alkyl, cycloalkyl, heterocycloalkyl, aryl, or heteroaryl. In certain preferred compounds of formulae 2 and 3, and in pharmaceutically acceptable salts and solvates thereof, R 1 is —C(O)CH 3 ; alternatively expressed, R 2 in a group of formula 8 is CH 3 .
The present invention is further directed to, various methods of making compounds of formulae 2, 3, 4 (nelfinavir free base), and 7 (nelfinavir mesylate), as described above. Other methods of preparing nelfinavir free base using compounds of formulae 2 and 3 are described in U.S. patent application Ser. No. 08/708,607, filed Sep. 5, 1996, which application also is entirely incorporated herein by reference. Other methods of using compounds of Formulae 2 and 3 are disclosed in JP 95-248183 and JP 95-248184, each of which is entirely incorporated herein by reference.
As used in the present application, the following definitions apply:
The term “alkyl” as used herein refers to substituted or unsubstituted, straight or branched chain groups, preferably, having one to eight, more preferably having one to six, and most preferably having from one to four carbon atoms. The term “C 1 -C 6 alkyl” represents a straight or branched alkyl chain having from one to six carbon atoms. Exemplary C 1 -C 6 alkyl groups include methyl, ethyl, n-propyl, isopropyl, butyl, isobutyl, sec-butyl, t-butyl, pentyl, neo-pentyl, hexyl, isohexyl, and the like. The term “C 1 -C 6 alkyl” includes within its definition the term “C 1 -C 4 alkyl.”
The term “cycloalkyl” represents a substituted or unsubstituted, saturated or partially saturated, mono- or poly-carbocyclic ring, preferably having 5-14 ring carbon atoms. Exemplary cycloalkyls include monocyclic rings having from 3-7, preferably 3-6, carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and the like. Exemplary cycloalkyls are C 5 -C 7 cycloalkyls, which are saturated hydrocarbon ring structures containing from five to seven carbon atoms.
The term “aryl” as used herein refers to an aromatic, monovalent monocyclic, bicyclic, or tricyclic radical containing 6, 10, 14, or 18 carbon ring atoms, which may be unsubstituted or substituted, and to which may be fused one or more cycloalkyl groups, heterocycloalkyl groups, or heteroaryl groups, which themselves may be unsubstituted or substituted by one or more suitable substituents. Illustrative examples of aryl groups include, but are not limited to, phenyl, naphthyl, anthryl, phenanthryl, fluoren-2-yl, indan-5-yl, and the like.
The term “halogen” represents chlorine, fluorine, bromine, or iodine. The term “halo” represents chloro, fluoro, bromo, or iodo.
The term “carbocycle” represents a substituted or unsubstituted aromatic or a saturated or a partially saturated 5-14 membered monocyclic or polycyclic ring, which is substituted or unsubstituted, such as a 5- to 7-membered monocyclic or 7- to 10-membered bicyclic ring, wherein all the ring members are carbon atoms.
A “heterocycloalkyl group” is intended to mean a non-aromatic, monovalent monocyclic, bicyclic, or tricyclic radical, which is saturated or unsaturated, containing 3, 4, 5, 6, 7. 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 ring atoms, and which includes 1, 2, 3, 4, or 5 heteroatoms selected from nitrogen, oxygen, and sulfur, wherein the radical is unsubstituted or substituted, and to which may be fused one or more cycloalkyl groups, aryl groups, or heteroaryl groups, which themselves may be unsubstituted or substituted. Illustrative examples of heterocycloalkyl groups include, but are not limited to, azetidinyl, pyrrolidyl, piperidyl, piperazinyl, morpholinyl, tetrahydro-2H-1,4-thiazinyl, tetrahydrofuryl, dihydrofuryl, tetrahydropyranyl, dihydropyranyl, 1,3-dioxolanyl, 1,3-dioxanyl, 1,4-dioxanyl, 1,3-oxathiolanyl, 1,3-oxathianyl, 1,3-dithianyl, azabicylo[3.2.1]octyl, azabicylo[3.3.1]nonyl, azabicylo[4.3.0]nonyl, oxabicylo[2.2.1]heptyl, 1,5,9-triazacyclododecyl, and the like.
A “heteroaryl group” is intended to mean an aromatic monovalent monocyclic, bicyclic, or tricyclic radical containing 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 ring atoms, including 1, 2, 3, 4, or 5 heteroatoms selected from nitrogen, oxygen, and sulfur, which may be unsubstituted or substituted, and to which may be fused one or more cycloalkyl groups, heterocycloalkyl groups, or aryl groups, which themselves may be unsubstituted or substituted. Illustrative examples of heteroaryl groups include, but are not limited to, thienyl, pyrrolyl, imidazolyl, pyrazolyl, furyl, isothiazolyl, furazanyl, isoxazolyl, thiazolyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, triazinyl, benzo[b]thienyl, naphtho[2,3-b]thianthrenyl, isobenzofuranyl, chromenyl, xanthenyl, phenoxathienyl, indolizinyl, isoindolyl, indolyl, indazolyl, purinyl, isoquinolyl, quinolyl, phthalazinyl, naphthyridinyl, quinoxyalinyl, quinzolinyl, benzothiazolyl, benzimidazolyl, tetrahydroquinolinyl, cinnolinyl, pteridinyl, carbazolyl, beta-carbolinyl, phenanthridinyl, acridinyl, perimidinyl, phenanthrolinyl, phenazinyl, isothiazolyl, phenothiazinyl, and phenoxazinyl.
The term “acyl” represents L 6 C(O)L 4 , wherein L 6 is a single bond, —O, or —N, and further wherein L 4 is preferably alkyl, amino, hydroxyl, alkoxyl, or hydrogen. The alkyl, amino, and alkoxyl groups optionally can be substituted. An exemplary acyl is a C 1 -C 4 alkoxycarbonyl, which is a straight or branched alkoxyl chain having from one to four carbon atoms attached to a carbonyl moiety. Exemplary C 1 -C 4 alkoxycarbonyl groups include methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, and the like. Another exemplary acyl is a carboxy wherein L 6 is a single bond and L 4 is alkoxyl, hydrogen, or hydroxyl. A further exemplary acyl is N—(C 1 -C 4 )alkylcarbamoyl (L 6 is a single bond and L 4 is an amino), which is a straight or branched alkyl chain having from one to four carbon atoms attached to the nitrogen atom of a carbamoyl moiety. Exemplary N—(C 1 -C 4 )alkylcarbamoyl groups include N-methylcarbamoyl, N-ethylcarbamoyl, N-propylcarbamoyl, N-isopropylcarbamoyl, N-butylcarbamoyl, and N-t-butylcarbamoyl, and the like. Yet another exemplary acyl is N,N-di(C 1 -C 4 )alkylcarbamoyl, which has two straight or branched alkyl chains, each having from one to four carbon atoms attached to the nitrogen atom of a carbamoyl moiety. Exemplary N,N-di(C 1 -C 4 )alkylcarbamoyl groups include N,N-dimethylcarbamoyl, N,N-,ethylmethylcarbamoyl, N,N-methylpropylcarbamoyl, N,N-ethylisopropylcarbamoyl, N,N-butylmethylcarbamoyl, N,N-sec-butylethylcarbamoyl, and the like.
Suitable protecting groups are recognizable to those skilled in the art. Examples of suitable protecting groups can be found in T. Green & P. Wuts, Protective Groups in Organic Synthesis (2d ed. 1991), which is incorporated herein by reference.
The term “aralkyl” as used herein refers to any substituted or unsubstituted group that is sp 3 hybridized at the point of attachment that also possesses an aromatic ring or rings with that group.
The term “pseudohalogen” as used herein refers to azides, cyanides, isocyanates, and isothiocyanates.
The term “N-hydroxyheterocyclic” as used herein refers to substituted and unsubstituted groups having an oxygen atom at the point of attachment that is also bonded to the nitrogen of a nitrogen heterocyclic ring or ring system. Examples of such groups include:
The term “alkyl ester” as used herein refers to ester groups where the group attached to the esterilying oxygen is an alkyl group.
The term “mixed carbonate” as used herein refers to compounds containing the functional group
where R a and R b independently are alkyl, aryl, or aralkyl groups.
The term “ester of an aromatic or heteroaromatic acid” as used herein refers to carboxylic acids wherein the carboxyl group is attached directly to a substituted or unsubstituted aromatic or heteroaromatic ring, such as benzoic acid or 2-furoic acid.
The term “DABCO” as used herein refers to the reagent 1,4-diazabicyclo[2.2.2]octane.
The term “DBN” as used herein refers to the reagent 1,5-diazabicyclo[4.3.0]non-5-ene.
The term “DBU” as used herein refers to the reagent 1,8-diazabicyclo[5.4.0]undec-7-ene.
The term “silyl ether” as used herein refers to the group:
wherein R c , R d , and R e independently are alkyl, aryl or aralkyl groups.
The term “perfluoralkanesulfonate” as used herein refers to alkane sulfonate esters wherein one or more of the hydrogens are replaced by fluorines.
The term “vinyl alkyl ether” as used herein refers to ether groups where an alkyl group and a substituted or unsubstituted olefin-containing group are bonded to the ethereal oxygen, and the olefin-containing group is bonded to the ethereal oxygen at one of the doubly-bonded carbons.
The term “arylsufonic acid” as used herein refers to groups of formula:
wherein Ar is a substituted or unsubstituted aromatic ring.
The term “leaving group” as used herein refers to any group that departs from a molecule in a substitution reaction by breakage of a bond. Examples of leaving groups include, but are not limited to, halides, arenesulfonates, alkylsulfonates, and triflates.
The term “arenesulfonate” as used herein refers to any substituted or unsubstituted group that is an ester of an arylsulfonic acid.
The term “alkyl or aryl carbodiimides” as used herein refers to any reagent of formula R f —N═C═N—R g , wherein R f and R g independently are aryl, alkyl, or aralkyl.
The term “DMF” as used herein refers to the solvent N,N-dimethylformamide.
The term “NMP” as used herein refers to the solvent N-methyl-2-pyrolidinone.
The term “THF” as used herein refers to the solvent tetrahydrofuran.
The term “alkyl thiolates” as used herein refers to substituted or unsubstituted compounds that are metal salts of alkanethiols.
The term “trialkylsilyl halide” as used herein refers to compounds having a silicon that holds 3 alkyl groups that may be the same or different.
The term “hydrogenolysis” as used herein refers to a reaction in which a single bond is broken and hydrogens become bonded to the atom's that were formerly bonded.
Examples of substituents for alkyl and aryl include mercapto, thioether, nitro (NO 2 ), amino, aryloxyl, halogen, hydroxyl, alkoxyl, and acyl, as well as aryl, cycloalkyl, and saturated and partially saturated heterocycles. Examples of substituents for cycloalkyl include those listed above for alkyl and aryl, as well as aryl and alkyl.
Exemplary substituted aryls include a phenyl or naphthyl ring substituted with one or more substituents, preferably one to three substituents independently selected from halo; hydroxy; morpholino(C 1 -C 4 )alkoxy carbonyl; pyridyl (C 1 -C 4 )alkoxycarbonyl; halo (C 1 -C 4 )alkyl; C 1 -C 4 alkyl; C 1 -C 4 alkoxy; carboxy; C 1 -C 4 alkoxycarbonyl; carbamoyl; N—(C 1 -C 4 )alkylcarbamoyl; amino; C 1 -C 4 alkylamino; di(C 1 -C 4 )alkylamino; or a group of the formula —(CH 2 ) a —R 7 where a is 1, 2, 3, or 4, and R 7 is hydroxy, C 1 -C 4 alkoxy, carboxy, C 1 -C 4 alkoxycarbonyl, amino, carbamoyl, C 1 -C 4 alkylamino, or di(C 1 -C 4 )alkylamino.
Another substituted alkyl is halo(C 1 -C 4 )alkyl, which represents a straight or branched alkyl chain having from one to four carbon atoms with 1-3 halogen atoms attached to it. Exemplary halo(C 1 -C 4 )alkyl groups include chloromethyl, 2-bromoethyl, 1-chloroisopropyl, 3-fluoropropyl, 2,3-dibromobutyl, 3-chloroisobutyl, iodo-t-butyl, trifluoromethyl, and the like.
Another substituted alkyl is hydroxy(C 1 -C 4 )alkyl, which represents a straight or branched alkyl chain having from one to four carbon atoms with a hydroxy group attached to it. Exemplary hydroxy(C 1 -C 4 )alkyl groups include hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxyisopropyl, 4-hydroxybutyl, and the like.
Yet another substituted alkyl is C 1 -C 4 alkylthio(C 1 -C 4 )alkyl, which is a straight or branched C 1 -C 4 alkyl group with a C 1 -C 4 alkylthio group attached to it. Exemplary C 1 -C 4 alkylthio(C 1 -C 4 )alkyl groups include methylthiomethyl, ethylthiomethyl, propylthiopropyl, sec-butylthiomethyl, and the like.
Yet another exemplary substituted alkyl is heterocycle(C 1 -C 4 )alkyl, which is a straight or branched alkyl chain having from one to four carbon atoms with a heterocycle attached to it. Exemplary heterocycle(C 1 -C 4 )alkyls include pyrrolylmethyl, quinolinylmethyl, 1-indolylethyl, 2-furylethyl, 3-thien-2-ylpropyl, 1-imidazolylisopropyl, 4-thiazolylbutyl, and the like.
Yet another substituted alkyl is aryl(C 1 -C 4 )alkyl, which is a straight or branched alkyl chain having from one to four carbon atoms with an aryl group attached to it. Exemplary aryl(C 1 -C 4 )alkyl groups include phenylmethyl, 2-phenylethyl, 3-naphthyl-propyl, 1-naphthylisopropyl, 4-phenylbutyl, and the like.
The heterocycloalkyls and heteroaryls can, for example, be substituted with 1, 2, or 3 substituents independently selected from halo; halo(C 1 -C 4 )alkyl; C 1 -C 4 alkyl; C 1 -C 4 alkoxy; carboxy; C 1 -C 4 alkoxycarbonyl; carbamoyl; N—(C 1 -C 4 )alkylcarbamoyl; amino; C 1 -C 4 alkylamino; di(C 1 -C 4 )alkylamino; or a group having the structure —(CH 2 ) a —R 7 where a is 1, 2, 3, or 4, and R 7 is hydroxy, C 1 -C 4 alkoxy, carboxy, C 1 -C 4 alkoxycarbonyl, amino, carbamoyl, C 1 -C 4 alkylamino, or di(C 1 -C 4 )alkylamino.
Examples of substituted heterocycloalkyls include, but are not limited to, 3-N-t-butyl carboxamide decahydroisoquinolinyl and 6-N-t-butyl carboxamide octahydro-thieno[3,2-c]pyridinyl. Examples of substituted heteroaryls include, but are not limited to, 3-methylimidazolyl, 3-methoxypyridyl, 4-chloroquinolinyl, 4-aminothiazolyl, 8-methylquinolinyl, 6-chloroquinoxalinyl, 3-ethylpyridyl, 6-methoxybenzimidazolyl, 4-hydroxyfuryl, 4-methylisoquinolinyl, 6,8-dibromoquinolinyl, 4,8-dimethylnaphthyl, 2-methyl-1,2,3,4-tetrahydroisoquinolinyl, N-methyl-quinolin-2-yl, 2-t-butoxycarbonyl-1,2,3,4-isoquinolin-7-yl, and the like.
A “pharmaceutically acceptable solvate” is intended to mean a solvate that retains the biological effectiveness and properties of the biologically active components of compounds of formulae 2 and 3.
Examples of pharmaceutically acceptable solvates include, but are not limited to, compounds prepared using water, isopropanol, ethanol, methanol, DMSO, ethyl acetate, acetic acid, or ethanolamine.
In the case of solid formulations, it is understood that the inventive compounds can exist in different forms, such as stable and metastable crystalline forms and isotropic and amorphous forms, all of which are intended to be within the scope of the present invention.
A “pharmaceutically acceptable salt” is intended to mean those salts that retain the biological effectiveness and properties of the free acids and bases and that are not biologically or otherwise undesirable.
Examples of pharmaceutically acceptable salts include, butare not limited to, sulfates, pyrosulfates, bisulfates, sulfites, bisulfites, phosphates, monohydrogenphosphates, dihydrogenphosphates, metaphosphates, pyrophosphates, chlorides, bromides, iodides, acetates, propionates, decanoates, caprylates, acrylates, formates, isobutyrates, caproates, heptanoates, propiolates, oxalates, malonates, succinates, suberates, sebacates, fumarates, maleates, butyne-1,4-dioates, hexyne-1,6-dioates, benzoates, chlorobenzoates, methylbenzoates, dinitrobenzoates, hydroxybenzoates, methoxybenzoates, phthalates, sulfonates, xylenesulfonates, phenylacetates, phenylpropionates, phenylbutyrates, citrates, lactates, y-hydroxybutyrates, glycolates, tartrates, methanesulfonates, propanesulfonates, naphthalene-1-sulfonates, naphthalene-2-sulfonates, and mandelates.
If the inventive compound is a base, the desired salt can be prepared by any suitable method known in the art, including treatment of the free base with an inorganic acid, such as hydrochloric acid; hydrobromic acid; sulfuric acid; nitric acid; phosphoric acid; and the like, or with an organic acid, such as acetic acid; maleic acid; succinic acid; mandelic acid; fumaric acid; malonic acid; pyruvic acid; oxalic acid; glycolic acid; salicylic acid; pyranosidyl acids such as glucuronic acid and galacturonic acid; alpha-hydroxy acids such as citric acid and tartaric acid; amino acids such as aspartic acid and glutamic acid; aromatic acids such as benzoic acid and cinnamic acid; sulfonic acids such a p-toluenesulfonic acid or ethanesulfonic acid; or the like.
If the inventive compound is an acid, the desired salt can be prepared by any suitable method known in the art, including treatment of the free acid with an inorganic or organic base, such as an amine (primary, secondary, or tertiary), an alkali metal or alkaline earth metal hydroxide, or the like. Illustrative examples of suitable salts include organic salts derived from amino acids such as glycine and arginine; ammonia; primary, secondary, and tertiary amines; and cyclic amines such as piperidine, morpholine, and piperazine, and inorganic salts derived from sodium, calcium, potassium, magnesium, manganese, iron, copper, zinc, aluminum, and lithium.
All inventive compounds that contain at least one chiral center can exist as single stereoisomers, racemates, and/or mixtures of enantiomers and/or diastereomers. All such single stereoisomers, racemates, and mixtures thereof are intended to be within the scope of the present invention. Preferably, the compounds of the present invention are used in a form that contains at least 90% of a single isomer (80% enantiomeric or diastereomeric excess), more preferably at least 95% (90% e.e. or d.e.), even more preferably at least 97.5% (95% e.e. or d.e.), and most preferably at least 99% (98% e.e. or d.e.). Compounds identified herein as single stereoisomers are meant to describe compounds used in a form that contains at least 90% of a single isomer.
The inventive compounds can be prepared by the novel methods of the present invention, which are described in detail below. Additionally, these compounds can be used to prepare nelfinavir free base and nelfinavir mesylate according to the inventive methods described below.
A reaction scheme for the conversion of 3-hydroxy-2-methylbenzoic acid derivatives to nelfinavir free base is as follows:
The acid 1 is commercially available from Lancaster Labs and Sugai Chemical Industries, Ltd. in Japan. The acid 1 also can be obtained according to the procedure described in U.S. Pat. No. 5,484,926, for the Preparation of 9C.
When R 1 is an acyl group or an ester of an aromatic or heteroaromatic acid, R 1 can be installed onto 3-hydroxy-2-methylbenzoic acid (Step 1) using the corresponding acyl halides or anhydrides in typical organic solvents for these types of reactions, such as halogenated solvents, ethers, and hydrocarbons accompanied by a base. Such bases typically are inorganic bases, such as metal hydroxides, bicarbonates, and carbonates, or organic bases, such as amines like triethylamine, diethylamine, diethyl isopropylamine, DABCO, or related di- or trialkylamines, as well as amidine bases like DBU and DBN. These reactions typically are run anywhere from below room temperature to approximately 100° C. Alternatively, the esterification can be catalyzed by acids such as sulfuric acid when used in conjunction with anhydrides.
When R 1 is an ether group, R 1 can be installed using conditions that utilize the corresponding R 1 group bonded to a leaving group, which is subsequently displaced. These reactions generally are performed in most common organic solvents such as THF, diethyl ether, dioxane, methyl t-butyl ether, or other ethers; esters such as ethyl, methyl, and isopropyl acetate; halogenated solvents such as halogenated methanes and ethanes, chlorobenzene, and other halogenated benzenes; nitriles such acetonitrile and propionitrile; lower alcohols such as ethanol, isopropanol, t-butanol, and related alcohols; and polarorganic solvents such as dimethyiformamide, dimethylsulfoxide, N-methyl-2-pyrolidinone, and related amide-containing solvents. A base usually accompanies such a process. The bases typically are inorganic, such as metal hydroxides, bicarbonates, and carbonates, or organic, such as amines like triethylamine, diethylamine, diethyl isopropylamine, DABCO, or related di- or trialkylamines, as well as amidine bases like DBU and DBN. These reactions typically are run anywhere from below room temperature to approximately 100° C.
When R 1 is a silyl ether, it can be installed using the corresponding silyl halides or perfluoralkanesulfonates in most common organic solvents such as THF, diethyl ether, dioxane, methyl t-butyl ether, or other ethers; esters such as ethyl, methyl, and isopropyl acetate; halogenated solvents such as halogenated methanes and ethanes, chlorobenzene, and other halogenated benzenes; nitriles such acetonitrile and propionitrile; and polar organic solvents such as dimethylformamide, N-methyl-2-pyrolidinone, and related amide-containing solvents. A base usually accompanies such a process. The bases typically are inorganic bases, such as metal hydroxides, bicarbonates, and carbonates, or organic bases, such as amines like triethylamine, diethylamine, diethyl isopropylamine, DABCO, or related di- or trialkylamines, as well as amidine bases like DBU and DBN.
When R 1 is part of an acetal or ketal group, R 1 can be installed by alkylation with the corresponding α-haloether in a manner similar to other alkyl halides as described above. Alternatively, acid-promoted addition of 3-hydroxy-2-methylbenzoic acid to the corresponding vinyl alkyl ether can be used. These reactions are promoted by both organic acids (such as p-toluenesulfonic and related alkyl and arylsulfonic acids, trifluoroacetic acid and related organic carboxylic acids with a pK of less than 2) and inorganic acids (such as sulfuric, hydrochloric, phosphoric, and nitric acids).
The group X is installed in Step 2 by reaction of the carboxylic acid derivative 2. The acyl halides of formula 3 can be prepared using inorganic halogenating agents such as thionyl chloride or bromide, phosphorus trichloride or -bromide, phosphorus pentachloride or bromide, or organic agents such as oxalyl chloride or trichlorisocyanuric acid. This process can be catalyzed by DMF or a related alkyl amide.
Esters of formula 3 can be prepared in a variety of ways starting from the acid chloride (compounds of formula 3) by combination with the desired alcohol in the presence of an organic or inorganic base stated previously. Alternatively, the ester can be produced by acid-promoted esterification in the presence of the desired alcohol. The sulfonates usually are made by reaction of the carboxylic acid derivatives (compounds of formula 2) with alkyl or arylsulfonyl chlorides in the presence of an organic amine base such as triethylamine in a non-polar solvent at temperatures below 0° C. The pseudohalogen derivatives generally are made from the acid halides (compounds of formula 3) by reaction with inorganic pseudohalide in the presence of a base. The heteroaryl derivatives (compounds of formula 2) also are made from the acid halides of formula 3 utilizing the specific heteroaryl compound in the presence of an amine base in a non-polar solvent. The N-hydroxyheterocyclic derivatives can be made from the acid halides of formula 3 as above and can also be generated using alkyl or aryl carbodiimides and an amine base as condensing agents.
The coupling of compound 3 to amine 6 (Step 3) can be carried out in a variety of ways, depending on the identity of X. When a free acid is used (X=OH), the coupling can be performed using carbodiimide based methods utilizing any of the common reagents of this class including dicyclohexylcarbodiimide or related dialkylcarbodiimides, EDC (salts of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide) or related water soluble reagents along with an organic amine base in polar organic solvents such as dioxane, DMF, NMP, and acetonitrile in the presence of an N-hydroxyheterocyclic including hydroxysuccinimide or N-hydroxybenzotrazole ester. When X is a halogen or pseudohalogen, the coupling can be performed in most common organic solvents such as THF; diethyl ether, dioxane, methyl t-butyl ether, or other ethers; acetone, cyclohexanone, methyl isobutylketone and other ketones; esters such as ethyl, methyl, and isopropyl acetate; halogenated solvents such as halogenated methanes and ethanes; chlorobenzene and other halogenated benzenes; nitriles such acetonitrile and propionitrile; lower alcohols such as ethanol, isopropanol, t-butanol, and related alcohols; and polar organic solvents such as dimethylformamide, dimethylsulfoxide, N-methyl-2-pyrolidinone, and related amide-containing solvents. A base frequently is used and can be any of a number of inorganic bases (such as metal hydroxides, bicarbonates, and carbonates) or organic bases (such as amines like. triethylamine, diethylamine, diethyl isopropylamine, DABCO, or related di- or trialkylamines, as well as amidine bases like DBU and DBN).
Protecting group removal is accomplished using any of the standard methods for deprotecting a particular class of protecting group. Esters and carbonates usually are removed with aqueous or alcoholic solutions of inorganic bases, such as metal hydroxides, carbonates, and bicarbonates, at ambient temperatures up to 100° C. Ethers are deprotected using boron- based Lewis acidic compounds such as BBr 3 and BCl 3 , alkyl thiolates, or trialkylsilyl halides. Either ether or carbonate protecting groups that contain benzyl groups bonded to heteroatoms can be removed by hydrogenolysis with a palladium or platinum catalyst. Acetal-based protecting groups can be removed under aqueous or alcoholic acidic conditions, promoted by Lewis acids such as transition metal halides or halides of the Group 3 metals, or by protic organic acids (such as p-toluenesulfonic and related alkyl and arylsulfonic acids, trifluoroacetic acid and related organic carboxylic acids with a pK of less than 2) and inorganic acids (such as sulfuric, hydrochloric, phosphoric, and nitric acids). Silylether protecting group removal can be accomplished by aqueous or alcoholic acid or base or by fluoride ion promoted desilylation by use of inorganic fluoride sources such as potassium or cesium fluoride or by tetralkylammonium fluoride salts.
Nelfinavir mesylate can be prepared from 3-acetoxy-2-methylbenzoyl chloride (acid chloride). The acid chloride can be prepared from the corresponding 3-hydroxy-2-methylbenzoic acid in the following two step procedure:
In the production of the acid chloride, the acid 1 is converted to the acetoxy acid (a compound of formula 2), which is treated with thionyl chloride to give 3-acetoxy-2-methylbenzoyl chloride in good yield.
The acid chloride then can be coupled to the amine 6 under classical conditions resulting in the production of nelfinavir free base as follows:
The acid chloride is treated with the amine 6 in the presence of triethylamine in THF at ambient temperature for 30 minutes followed by an aqueous basic hydrolysis of the acetate group to give nelfinavir free base. The free base can be converted to nelfinavir mesylate by methods described in more detail below.
PREPARATION OF NELFINAVIR FREE BASE FROM 3-ACETOXY-2-METHYLBENZOIC CHLORIDE
Summary of the Process
To obtain 3-acetoxy-2-methylbenzoyl chloride, 3-hydroxy-2-methylbenzoic acid was slurried in acetic acid with acetic anhydride and catalytic sulfuric acid. Acetylation of the hydroxy group was complete within two hours at ambient temperature. After complete reaction, the resulting slurry was poured into water, and the product was isolated by filtration. The wet cake was reslurried in water, isolated by filtration, and dried under vacuum. Product was obtained in 80-90% yield with an apparent purity of 89-92% by HPLC. Crude, dry 3-acetoxy-2-methylbenzoic acid was dissolved in four volumes of ethyl acetate with refluxing. The resulting solution was cooled to <70° C., and five volumes of hexanes were added. The mixture was returned to reflux and then cooled to <10° C. for 1 hour. The slurry was filtered, rinsing the reactor with filtrate. The product was dried under vacuum. Recrystallization improved the HPLC UV apparent purity from 89-92% to >98%. The single largest impurity dropped from 4-5% to ˜0.5%. The product was 3-acetoxy-2-methylbenzoic acid.
3-Acetoxy-2-methylbenzoic acid was slurried in methyl-t-butyl ether (MTBE) and treated with 1.2 equivalents of thionyl chloride and catalytic dimethylformamide. After three hours at ambient temperatures, the reaction was complete, giving a brown soluton. Solvent (MTBE) was removed by vacuum distillation. Residual thionyl chloride was removed by addition of toluene followed by vacuum distillation. The resulting 3-acetoxy-2-methylbenzoyl chloride was isolated either directly as an oil or by crystallization from two volumes of heptane at <10° C. Product was obtained in >100% yield when isolated as an oil and 82-85% yield when crystallized from heptane.
To obtain compound 6 for the coupling, a compound of formula 5 (made as described below) was refluxed in a mixture of ethanol and aqueous NaOH to cleave the CBZ protecting group forming a compound of formula 6. Water and HCl were added to dissolve the Na 2 CO 3 and neutralize excess NaOH, giving a biphasic mixture. The mixture was cooled, and the lower aqueous layer was removed. Triethylamine was added followed by a solution of 3-acetoxy-2-methylbenzoyl chloride in tetrahydrofuran to give an acetate of the compound of formula 4. Aqueous NaOH was added, and the mixture was heated to reflux to give a compound of formula 4. The mixture was concentrated at atmospheric pressure to remove tetrahydrofuran, triethylamine, and most of the ethanol. The mixture was added to a heated solution of water and glacial acetic acid to precipitate the product. The pH was adjusted with additional acid, and the solids were filtered off while hot. The wet cake was rinsed with hot water and dried to give crude nelfinavir free base.
This method is described in more detail below.
Preparation of 3-Acetoxy-2-methylbenzoic Acid
PROCEDURE
Materials
3-hydroxy-2-methyl-
FW 152.15
3500
g
1.0 equiv
benzoic acid
acetic acid
8750
mL
sulfuric acid
70
mL
acetic anhydride
FW 102.1
d 1.082
2390
mL
1.1 equiv
purified water
28000
mL
Acetic acid (8750 mL), 3-hydroxy-2-methylbenzoic acid (3500 g), and sulfuric acid (70 mL) were charged into a 22 liter reactor. The reactor contents were stirred to give a homogeneous mixture. The mixture exothermed to 36° C. Acetic anhydride (2390 mL) was added to the mixture in the 22 L reactor. An exotherm warmed the reactor contents from 36 to 44° C. The reaction mixture was stirred at ambient temperature for two hours (reactor contents allowed to cool slowly). The reaction was tested for complete conversion of the starting material by TLC. The reaction mixture was generally a tan slurry at the completion of the reaction.
Purified water (17500 mL) was added to a 50 L extractor, and the reaction mixture from the 22 L reactor was added to this water. The 22 L reactor was rinsed into the 50 L extractor with purified water (3500 mL). The reaction mixture was vacuum filtered, washing the reactor and filter cake with purified water (3500 mL). The wet filter cake was transferred to a 50 L extractor,,and purified water (14000 mL) was added, with stirring, to obtain a homogeneous slurry. The reslurried mixture was vacuum filtered, and the reactor and filter cake were rinsed with purified water (3500 mL). The filter cake was pulled as dry as possible and then transferred to drying pans. The product was dried in a vacuum oven at 60-80° C. and ≧28 mm Hg for 12-72 hours. Theoretical yield: 4466 g. Actual weight produced: 3910 g (87.6%). HPLC assay: 89.4% or 87.7%.
Purification was achieved as follows. The crude 3-acetoxy-2-methylbenzoic acid (3910 g from above) and ethyl acetate (16.0 L) were charged to a 50 L reactor. The reactor contents were heated to reflux (77° C.) until all solids went into solution. The reactor contents were cooled to <70° C. Hexanes (19.5 L) were added to the reactor. The reactor contents were again heated to reflux (69° C.), and then the mixture was cooled to <10° C. for 1 hour. The cooled slurry from this step was vacuum filtered, and the reactor was rinsed with cold mother liquors. The filter cake was pulled as dry as possible and then transferred to drying pans. The product was dried in a vacuum oven at 60-70° C. and ≧28 mm Hg for 12-72 hours. Theoretical yield: 3910 g. Actual weight produced: 3128 g (80%). This procedure improves the HPLC UV apparent purity from 89-92% to >98%. The single largest impurity drops from 4-6% to <1% The isolated product is a tan solid. 1 H NMR δ 8.0 (d, 1H), 7.3 (overlapping m, 2H), 2.5 (s, 3H), 2.3 (s, 3H).
Preparation of 3-Acetoxy-2-methylbenzoyl Chloride
PROCEDURE:
Materials
MW
d
wt
equiv.
3-acetoxy-2-methylbenzoic
194.19
3000 g
1.0
acid
methyl-t-butyl ether
12000 ml
thionyl chloride
118.97
1.638
1350 ml
1.2
dimethylformamide
73.09
0.944
60 ml
0.05
toluene
7500 ml
heptane
7500 ml
A 22 L reactor was purged with nitrogen and charged with recrystallized 3-acetoxy-2-methylbenzoic acid (3000 g), MTBE (12000 ml), and dimethylformamide (60 ml). The reactor contents were stirred to give a homogeneous mixture. Thionyl chloride (1350 ml) was added to the reactor. This reaction mixture was stirred at ambient temperature for 19 hours. (Generally no more than 3 hours are required for complete reaction, but the mixture can be held longer for convenience). The reaction solution was transferred to a Bochi rotovap, and the reactor was rinsed with toluene (1500 ml). The solution was concentrated as far as possible, maintaining the bath temperature at 40-50° C. Toluene (6000 ml) was added to this concentrated solution. The toluene was distilled by rotovap to drive off excess thionyl chloride. The concentrate was transferred, back to the 22 L reactor, and the Büchi flask was rinsed with heptane (6000 ml). The heptane mixture was cooled to <5° C. under nitrogen. After holding the crystallization mixture at <5° C. for >30 minutes, the mixture was filtered, and the filter cake was washed with chilled heptane (1500 ml, <5° C.). The filter cake was dried in a vacuum oven at 15-20° C. and 228 mm Hg for 24 hours, giving a tan, granular solid. Theoretical yield: 3285 g. Actual weight produced: 2704 g (82.3%). HPLC assay 97.51%; 1 H NMR δ 8.1 (d, 1H), 7.4 (overlapping m, 2H), 2.4 (s, 6H).
Conversion of 3-Acetoxy52-methylbenzoyl Chloride and Compound 6 to Nelfinavir Free Base
Step A: Conversion of Compound 5 to Compound 6.
A 22 liter 3-neck round bottom flask (“RBF”), fitted with a condenser, temperature probe, and mechanical stirrer, was charged with a compound of formula 5 (1 kg. 97.7%, 1.72 mol, 1.00 eq) (which can be prepared as described below), ethanol (5 I, 95%), NaOH (280 ml, 50%, 5.33 mol. 3.1 eq), and water (2 I, DI). The mixture was stirred and heated to reflux (80-82° C.). All solids dissolved at 50° C. to give a clear yellow solution. The mixture became hazy with Na 2 CO 3 precipitation as the reaction proceeded (Vol=8280 ml). The deprotection was monitored by HPLC. Analysis at 210 minutes showed complete consumption of the compound of formula 5,0.95% oxazolidinone, 36% benzyl alcohol, and 62.5% of a compound of formula 6. Analysis at 300 minutes showed 0.34% oxazolidinone, 36% benzyl alcohol and 62.6% of compound of formula 6. Water (1260 ml) was added to the mixture to dissolve all solids, and the mixture was cooled to 67° C. (Vol=9540 ml). HCl (344 ml, 6 N, 2.06 mol, 1.2 eq.) was then added to the mixture. The mixture was agitated 10 minutes and then allowed to settle for 20 minutes to give two layers (Vol=9884 ml). The lower aqueous Na 2 CO 3 layer was removed at 60° C. The volume of the aqueous cut was 365 ml, pH=14. The pH of the clear yellow upper layer was 10-10.5. The upper layer was used directly in the next step.
Step B: Conversion of Compound 6 to an Acetate of Compound 4.
Chemicals
source
assay
Kg
L
d
mw
mol
equiv
Compound 6/EtOH
1040-090
(0.746)
433.65
(1.72)
1.00
triethylamine
Fisher
0.26
0.36
0.726
101.19
2.58
1.50
tetrahydrofuran
Fisher
0.40
0.45
0.889
72.11
3-acetoxy-2-methylbenzoyl
AC1322
98.9%
0.39
212.63
1.81
1.05
chloride
Reference:
1040-092
The solution from Step A was cooled to 25° C., triethylamine (360 ml, 2.58 mol. 1.50 eq) was added to the solution, and the mixture was cooled to 7° C. (pH=11.5-12.0). The mixture became hazy at 23° C. (Vol=9879 ml). This mixture was charged to a mixture of 3-acetoxy-2-methylbenzoyl chloride (388.5 g, 98.8 %, 1.81 mol, 1.05 eq) and tetrahydrofuran (440 ml) over 5 minutes. THF (10 ml) was used to complete the transfer. A 7.4° C. exotherm was observed. The mixture at the end of the addition was milky white. (Vol=10,717 ml). HPLC analysis after 30 minutes showed <0.2% of a compound of formula 6, 77% of the acetate of the compound of formula 4, 18.2% benzylalcohol, and no ester present. The milky mixture was used directly in the next step.
Step C: Saponification of Compound 4
Chemicals
source
assay
Kg
L
d
mw
mol
equiv
Acetate of Compound 4/PA
1040-092
(1.05)
609.83
(1.72)
1.00
NaOH
Fisher
50%
0.55
0.36
1.515
40.00
6.88
4.00
Water
DI
15.0
15
1.000
18.02
HOAc, glacial
Fisher
17.4 N
0.25
0.23
1.049
60.05
4.07
2.37
Ethanol, (5% methanol)
McCormick
95%
0.04
0.05
0.785
46.07
NaOH (50%, 364 ml, 6.88 mol, 4.0 eq) was added to the mixture from Step B. The milky mixture became clear, then hazy, light brown. The mixture was agitated at 20° C. for 35 minutes. HPLC showed 15.9%. benzylalcohol, 78.6% of compound 4, and no acetate (Vol=11,081 ml). The mixture was heated to reflux and partially concentrated by atmospheric distillation until the head temperature reached 82° C. The distillate volume was 4275 ml The pH of the mixture was 14. The pot volume was measured (Vol=6000 ml).
Water (5 L) and HOAc (100 mL) were charged to a 12 L 3-neck round bottom flask fitted with a temperature probe and mechanical stirrer. The solution was heated to 54° C. (pH=2-2.5) (Vol=5100 ml). One half of the compound 4 mixture produced above (3 L) was added to this warm aqueous acetic acid solution to precipitate fine white solids. The pH was then adjusted to 7-7.5 with HOAc (19 ml), and the temperature was 53° C. (Vol=8119 ml). The solids were filtered off at 53° C. using isolated vacuum. The filtration was quick and easy. The reactor and wet cake were rinsed with warm (35° C.) water (2.5 L), and the filtrates were combined. The wet cake was pulled dry for 15-20 minutes.
Water (5 L) and HOAc (100 mL) were charged again to the 12 L 3-neck round bottom flask. The solution was heated to 41° C. (Vol=5100 ml). The remaining half of the compound 4 reaction mixture (3 L) was added to the new warm aqueous acetic acid solution to precipitate fine white solids. The pH was then adjusted to 7-7.5 with HOAc (15 ml). The temperature was 44° C. (Vol=8115 ml). The solids were filtered off at 53° C. using isolated vacuum. The filtration was quick and easy. The reactor and wet cake were rinsed with warm (35° C.) water (2.5 L), and the filtrates were combined. The wet cake was pulled dry for 15-20 minutes.
The two wet cakes (3587 g) were dried under vacuum at 60° C. for 90 hours to give a dry wt of 1075.38 g crude Compound 4. Theoretical yield is 977 g.
Step D: Purification of Compound 4
Chemicals
source
assay
wt
ml
d
mw
mmol
equiv
Crude Compound 4
895-131
91.82%
290
g
567.79
469
1.00
Acetone
Fisher
4038
g
5105
0.791
58.08
Water
DI
1070
g
1070
1.000
18.02
Celite
Aldrich
29
g
Darco G-60 activated
Fisher
44
g
12.01
carbon
A 12 liter 3-neck RBF, fifted with a condenser, temperature probe, and mechanical stirrer, was charged with crude compound 4 (290 g, 92%, 469 mmol), activated carbon (Darco G-60, 44 g), acetone (4305 ml), and water (870 ml, Dl). The mixture was heated to reflux (60-64° C.) and held 45 minutes (Vol=5509 ml). The hot slurry was filtered through celite (29 g) using isolated vacuum. The reactor and filter cake were rinsed with acetone (200 ml), and the clear, light yellow filtrates were combined. The mixture was allowed to cool slowly to 25° C. over 2.5 hours with stirring to precipitate a fine white solid (Vol=5665 ml). The white slurry was cooled to 0-10° C. and held for 1 hour. The solids were filtered off using isolated vacuum, and the liquid level was pulled through the surface of the wet cake. The reactor and wet cake were rinsed with a cold (0-10° C.) mixture of acetone/water (2:1, 300 ml). The liquid level was pulled through the surface of the wet cake, and the reactor and wet cake were again rinsed with a cold (0-10° C.) mixture of acetone/water (2:1, 300 ml). The wet cake was pulled as dry as possible using isolated vacuum and rubber damming to give a wet weight of 581 g. The product was dried under vacuum at 65° C. for 16 hours to give a dry weight of 221.61 g of compound 4. Theoretical yield was 266.28 g. HPLC and ROI analysis showed 99% and 0.14% respectively. Adjusted yield was 82%.
The present invention also is directed to novel methods of converting nelfinavir free base, compound 4, to nelfinavir mesylate, compound 7. These methods are described in more detail below, including the method for preparing compound 4 from compound 5 and the method for preparing compound 5.
Procedure for Preparation of Compound 5
One equivalent 2S, 3R-N-Cbz-3-amino-1-chlorophenylsulfanylbutan-2-ol (which can be obtained from Kaneka Corporation or prepared as described in U.S. Pat. No. 5,484,926) is stirred in a sufficient volume of methanol, ethanol, isopropanol, or other low boiling alcoholic solvent at 20°-45° C. Isopropanol is the preferred solvent. A slight subcess of alkali base, such as sodium hydroxide or potassium hydroxide, as either an aqueous solution or as a solid, is added to this mixture with stirring. 10N sodium hydroxide is the preferred base. The mixture is stirred for 30 minutes to 24 hours until epoxide formation is complete. When the stir period is complete, the pH is adjusted to 6-7 with a proton acid such as HCl, either neat or dissolved in the reaction solvent.
A slight excess of 3S,4aR,8aR-3-N-t-butylcarboxamidodecahydroisoquinoline (which can be prepared as described in U.S. Pat. No. 5,256,783, which patent is entirely incorporated herein by reference) is added as either a dry solid or as a slurry to the reaction, and the mixture is heated to 40° C. to reflux for 12-24 hours or until the reaction is judged to be complete. Alternatively, 3S,4aR,8aR-3-N-t-butylcarboxamidodecahydroisoquinoline can be introduced to the reaction at the same time that the 2S, 3R-N-Cbz-3-amino-1-chlorophenylsulfanylbutan-2-ol is charged to reactor. The epoxide formation is allowed to proceed as described. In this case, the reaction is not neutralized to a pH of 6-7, but a fixed amount of proton acid is added to neutralize excess base remaining. In either case, the reaction is partially concentrated in vacuo. The mixture is diluted with an equal volume of water and heated to reflux. Alternatively, the reaction is fully concentrated, and acetone or other ketonic solvent is added. The mixture can be filtered at this point, then an equal amount of water is added, and the mixture is heated. The resultant mixture is cooled with stirring. The resultant slurry is filtered, washed with aqueous solvent, and dried to yield compound 5.
Procedure for Preparation of Nelfinavir Free Base (Compound 4)
In addition to the procedure described above, the following procedure can be used to convert compound 5 to the nelfinavir free base (compound 4):
One equivalent of compound 5, an excess of alkali base (such as sodium hydroxide or potassium hydroxide), and an alcoholic solvent (such as methanol, ethanol, or isopropanol) are combined, and the mixture is heated at reflux with stirring. 50% caustic soda is the preferred base and isopropanol is the preferred solvent. Water can be added to facilitate solubility of the base. When the reaction is judged complete, the mixture is cooled to 30° to 35° C., and the lower aqueous layer, if any, can be removed. The mixture is cooled to below 25° C. and an excess amount of organic base (such as diisopropylethyl amine or triethylamine) is added. Triethylamine is the base of choice.
A solution of excess 3-acetoxy-2-methylbenzbyl chloride in methanol, ethanol, isopropanol, THF, or other alcohol soluble solvents is slowly added to the cold mixture with stirring. THF is the preferred solvent.
An excess of alkali base, such as sodium hydroxide or potassium hydroxide, is added, and the mixture is heated at 40° C. to reflux with stirring. 50% caustic soda is the preferred base. When the reaction is judged complete, the mixture is cooled, and the lower aqueous layer is removed.
The reaction mixture is partially concentrated in vacuo. If deemed necessary, the mixture can be diluted with an alcohol solvent to facilitate stirring. Methanol is the preferred solvent. The mixture is added to aqueous acid to form a slurry. HCl is the preferred acid. The pH is adjusted to 7-8 with aqueous acid. The slurry is filtered and washed with water. The wet cake can be reslurried in water. The crude product is dried (partially or completely) or can be taken into the next step wet.
Either the dry or the crude, wet product is dissolved in aqueous acetone at reflux in the presence of activated carbon. The hot mixture is filtered, water is added, and the entire mixture is cooled with stirring to formn a slurry. The slurry is filtered, washed with aqueous acetone, and dried to give nelfinavir free base.
Other methods for preparing nelfinavir free base are disclosed in U.S. Pat. No. 5,484,926, and copending U.S. patent application of inventors S. Babu, B. Borer, T. Remarchuk, R 1 Szendroi, K. Whitten, J. Busse, and K. Albizati, entitled “Methods of Making HIV-Protease Inhibitors and Intermediates for Making HIV-Protease Inhibitors,” U.S. patent application Ser. No. 08/708,607, filed on Sep. 5, 1996, which application is incorporated herein by reference.
Procedure for Spray Drying Nelfinavir Free Base to Obtain Nelfinavir Mesylate
Generally, nelfinavir free base can be converted to nelfinavir mesylate using the following novel spray drying procedure.
Nelfinavir free base and an organic solvent (such as methanol, ethanol, isopropanol, THF, acetone, or MIBK) are mixed in a suitable vessel, and an equivalent amount of methanesulfonic acid is added. Ethanol is the preferred solvent. The mixture is stirred until nelfinavir mesylate is formed. The resultant slurry or solution is pumped into the spray dryer where the following settings are controlled:
Inlet Temperature:
100-190° C.
Outlet Temperature:
60-120° C.
Atomizer Type:
vane, cocurrent flow, or counter current flow
Drying Gas Rate:
depends on equipment scale
The inlet and outlet temperatures, feed rate, and atomizer type can be adjusted to optimize output and particle size distribution. Spray dried nelfinavir mesylate is collected at the spray dryer outlet collection point.
Specifically, this conversion was performed as described below.
19.4 kg±5% Alcohol (USP, 190 proof) and 6.00 kg±1% nelfinavir free base were added to a clean, dry 20-40L stainless steel container. The mixture was stirred until homogenous, then 1.04 kg±1% methanesulfonic acid, 99%, was added. The mixture was stirred until all solids were dissolved. A 0.2 μ filter cartridge was connected to the pump inlet, and the alcohol solution was pumped through the filter into the spray dryer set with the following initial settings:
Inlet Temperature:
160°
C.
Outlet Temperature:
90°
C.
Wheel Type:
50
mm vane wheel
Wheel Speed:
27000
rpm
Drying Gas Rate:
75
kgs./hour
The inlet and outlet temperatures, feed rate, and wheel speed can be adjusted to optimize output and particle size distribution. The specific spray dryer used was a Niro Atomizer Portable Spray Dryer, type HT (equipped for inert gas) connected to an active carbon filter for removal of organic solvent residues. After the bulk of the solution had been spray dried, the mixing tank was rinsed into the spray dryer with 1.0 kg±5% Alcohol, USP, 190 proof. The spray dried nelfinavir mesylate was collected in 80-100% theory yield.
Procedure for Precipitaton of Nelfinavir Free Base to Obtain Nelfinavir Mesylate
Alternatively, nelfinavir free base can be converted to nelfinavir mesylate using the following novel precipitation procedure.
Nelfinavir free base is slurried or dissolved in a suitable solvent (such as THF, methanol, or ethanol). THF is the preferred solvent. A molar equivalent amount of methanesulfonic acid is added, and the mixture is stirred until all solids dissolve. The solution is added to several volumes of an antisolvent (such as methyl t-butyl ether, diethyl ether, hexanes, or heptanes) that is rapidly stirring. Diethyl ether is the preferred antisolvent. After stirring, the mixture is filtered and washed with antisolvent. The solid is dried in a vacuum oven to yield nelfinavir mesylate.
Specifically, this conversion was performed as described below.
Nelfinavir free base (10.2 kg, 18.0 mol) and 24 L of tetrahydrofuran were added to a 100L reactor. Methanesulfonic acid (1.8 kg, 18.48 mol) also was added to the reactor. The reactor was stirred until all solids dissolved, and then the solution was filtered into a 100 gallon polypropylene tank containing 306 L methyl t-butyl ether or diethyl ether that was rapidly stirring. After stirring for 2 hours, the 100 gallon tank contents were filtered, washed with 17 L of methyl t-butyl ether or diethyl ether, and pulled as dry as possible. The solid was transferred to a rotocone drier and dried in a vacuum oven at 60-65° C. (at least 26 in. Hg or higher vacuum) for 12-72 hours or until the methyl t-butyl ether or diethyl ether content of the dried solid was below 1%. If necessary, the drier contents could be milled in a Fitzmill grinder to accelerate drying. Typical yields of nelfinavir mesylate range from 9 to 11 kg. (76%-92% theory).
In this application, Applicants have described certain theories and reaction mechanisms in an effort to explain how and why this invention works in the manner in which it works. These theories and mechanisms are set forth for informational purposes only. Applicants are not to be bound by any particular chemical, physical, or mechanical theory of operation.
While the invention has been described in terms of various preferred embodiments using specific examples, those skilled in the art will recognize that various changes and modifications can be made without departing from the spirit and scope of the invention, as defined in the appended claims. | HIV protease inhibitors inhibit or block the biological activity of the HIV protease enzyme, causing the replication of the HIV virus to terminate. These compounds can be prepared by the novel methods of the present invention using the novel inventive compounds and intermediates. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to insulation displacement contacts. More particularly, it relates to insulation displacement contacts which are useful in terminating more than a single conductor.
Insulation displacement contacts which terminate a single insulated conductor have been used for quite some time in the electrical connector industry. In general, an insulation displacement contact includes a bifurcated element having a pair of beams with a pair of closely spaced opposed termination surfaces. The beams separate in a V-shape, like a scissors, during termination. The termination surfaces include knife edge portions for penetrating the insulation of the electrical conductor.
An example of an insulation displacement contact is disclosed in U.S. Pat. No. 4,333,700 assigned to Bell Telephone Laboratories Incorporated.
Insulation displacement contacts are used to a large extent in 110 block housings used in the telecommunications industry with patch panels located in buildings and offices which have multi-line telephone and communication systems. Incoming wires from the telephone company are terminated by the 110 blocks located on the patch panel. Each insulation displacement contact is normally designed to terminate only a single wire or conductor. However, it is often desirable to terminate a second conductor by an insulation displacement contact.
A typical insulation displacement contact is not able to properly terminate more than a single insulated electrical conductor. If one tries to terminate a second conductor after a first conductor has been terminated and the V-shape has been formed, the integrity of the termination, i.e. conductor metal to contact metal, is often disturbed. This occurs because the contact beams are spread apart again during the termination of the second conductor, thus loosening the connection with the first conductor. The problem occurs when the conductor diameters are the same or different, however, it is exacerbated if the diameter of the second conductor is larger than the diameter of the first conductor.
There is currently on the market a contact known as the LSA-PLUS, which is commercially available from Krone, Inc., which is claimed to be able to terminate two conductors. The Krone LSA-PLUS contact is a slotted contact which is placed diagonally across the well of contact receiving housing which is modified to permit a twisting of the contact so as to continue a grip on the first terminated conductor while the second conductor is being terminated. The Krone LSA-PLUS contact requires a modification in the contact housing. In addition, the Krone LSA-PLUS contact relies on shear forces, like scissors, and has been known to cause undesirable deep nicks in the conductors.
OBJECTS OF THE INVENTION
It is therefore one object of this invention to provide an improved insulation displacement contact.
It is another object to provide an insulation displacement contact which will readily terminate more than a single conductor.
It is still another object to provide an insulation displacement contact which will terminate a second electrical conductor without disturbing the integrity of the termination of a first conductor.
It is yet another object to provide a dual wire insulation displacement contact which is usable with a standard 110 connector housing without substantial modifications to the housing.
SUMMARY OF THE INVENTION
In accordance with one form of this invention there is provided an electrical contact for terminating a pair of conductors. The contact includes first and second elongated beams connected together. A slot is formed between the beams. A first leg is connected to the first beam and extends into the slot. A second leg is connected to the second beam and also extends into the slot. The legs have elongated surfaces closely spaced and juxtaposed from one another for making contact with and thus terminating the conductors. Each leg is resilient along the elongated surface so that the act of terminating the second conductor, subsequent to the termination of the first conductor, will not substantially degrade the integrity of the termination of the first conductor.
In accordance with another form of this invention, there is provided an apparatus for terminating at least one conductor including a bifurcated contact including first and second furcations. Each furcation having first and second interconnected and interdependent resilient members. The first resilient members include conductor termination surfaces which are adjacent to one another. Upon the application on the first resilient members due to a force of the termination of a conductor, each resilient member will flex so that an amount of stress on the first resilient member is relieved by the second resilient member.
In yet another form of this invention, there is provided an insulation displacement contact including first and second cantilevered beams. A first simple beam is connected in two places to the first cantilevered beam and a second simple beam is connected in two places to the second cantilevered beam. Each of the simple beams have a termination surface juxtaposed to one another.
BRIEF DESCRIPTION OF THE DRAWINGS
The subject matter which is regarded as the invention is set forth in the appended claims. The invention itself, however, together with further objects and advantages thereof, may be better understood by reference to the following description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a front elevational view of the contact of the subject invention after having been stamped, but prior to the bending of the furcations.
FIG. 2 is a partial front elevational view of the contact of FIG. 1 subsequent to the bending of the furcations and showing a portion of the well of the housing receiving the contact.
FIG. 3 is a pictorial view of the contact shown in FIG. 2.
FIG. 4 is a side elevation view of the contact of FIG. 2, however, showing an alternative lower portion.
FIG. 5 is a more detailed front elevational view of a portion of the contact of FIG. 2 and showing a pair of conductors during the termination process.
FIG. 6 is more detailed view of a portion of the contact of FIG. 5 showing the preferred position of the two conductors after termination.
FIG. 7 is side elevational view showing a standard 110 multiple well housing for receiving a plurality of the contacts of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now more particularly to FIG. 1, there is provided electrical contact 10 which is shown in a planer condition immediately after stamping, but prior to bending the operation, which will be explained below. Preferably, contact 10 is made from a phosphor bronze alloy, and more preferably, it is made from a beryllium copper alloy. Contact 10 is bifurcated and includes a pair of furcations 12 and 14. Furcation 12 includes elongated cantilevered beam 16 and a simple beam in the form of C-shaped leg 18 connected thereto at two spaced apart locations 19 and 21 on the cantilevered beam. A space 20 is provided between a portion of the leg 18 and beam 16 and between the spaced apart connection points 19 and 21. Furcation 14 is identical to furcation 12 and includes cantilevered beam 22 and a simple beam in the form of C-shaped leg 24. Beams 16 and 22 are integral with one another and merge together in a middle region of the contact generally indicated as 26.
An elongated stud element 28 extends below the middle region 26. In the embodiment of FIG. 1, the major portion of stud element 28 is in the form of a standard insulation displacement contact for terminating a single conductor. In the embodiment shown in FIG. 4, the major portion of stud element 28 is in the form of a post which is to be connected to a substrate such as a printed circuit board.
Referring now to FIGS. 2 and 3, leg 18, and thus its major plane is bent approximately 90° with respect to beam 16, and thus its major plane. Likewise, leg 24 is bent approximately 90° with respect to beam 22. The phantom lines 30, 32, 34 and 36, shown in FIG. 1, illustrate the approximate position where the bends occur which are near the places of connection 19 and 21 between the legs and the beams. The beams 16 and 22 as illustrated in FIG. 2 are rotated 90° from their position shown in FIG. 1. After this bending operation, a slot generally indicated as 29 is formed in the contact between the beams 16 and 22.
Leg 18 includes an elongated termination portion 38 which is closely spaced and juxtaposed to the elongated termination portion 40 of leg 24. Termination portion 38 includes termination surface 42, and termination portion 40 includes termination surface 44. Preferably the distance between the termination surfaces 42 and 44 when the contact is used in a standard 110 connector for terminating wire having an outside insulated diameter of 0.035 inches and an outside conductor diameter of 0.020 inches is approximately 0.012 inches.
The C-shaped legs 18 and 24 include sharp insulation cutting edges 46 and 48 for piercing the insulation on the conductors and skinning the metal of the conductors as they are placed in slot 29 for termination.
The contact as illustrated in FIG. 2 is received in a contact receiving well 50 of a multi-well 110 connector block 52 which is shown in phantom in FIG. 5. Well 50 is made of plastic and includes vertical sidewalls 54 and 56. The tops 58 and 60 of beams 16 and 22 are flared outwardly so as to make contact with upper portions of sidewalls 54 and 56 respectively.
Shoulder portion 62 of the contact, which is a part of stud 28, is wider than the major portion of the distance between the outside surfaces 64 and 66 of the beams and is approximately equal to the distances between the outside surfaces of the beams at the free ends of the top bent portions 58 and 60. The outside edges 67 and 69 of shoulder portion 62 contact the walls 54 and 56 of well 50. Spaces 72 and 74 are formed between the major portions of the outside surfaces of the beams 16 and 22 and the inside surfaces of the walls 54 and 56 of the well 50. These spaces permit the beams 16 and 22 to flex outwardly as will be explained below.
Referring now more particularly to FIGS. 5 and 6, there is provided first conductor 76 and second conductor 78 which have been terminated by contact 10. When the first conductor 76 is passed through slot 29, portions of its insulation 80 are removed by knife edges 46 and 48 as the conductor passes between the small gap 45 which exists between the termination surfaces 42 and 44. The conductive surfaces of conductor 76, which have been skinned by knife edges 46 and 48, contact termination surfaces 42 and 44. Each termination portion 38 and 40 of the C-shaped legs 18 and 24 bows inwardly as a result of the force created during the termination. In addition, the beams 16 and 22 bow outwardly as a result of the forces transferred from the connection points 19 and 21 of the C-shaped legs to the beams 16 and 22 with the outward bow primarily occurring below spaces 72 and 74 thereby providing stress relief to legs 18 and 24.
This outwardly flexing of the cantilevered beams permit the use of a very small gap between the termination surfaces of the C-shaped legs so that very high forces are generated during termination. The stress relief provided by the outward flexing of the beams reduce the possibility of over stressing the C-shaped legs.
With the first conductor 76 having been terminated, it is pressed towards the lower portion of the gap 45. The second conductor 78 is then inserted into slot 29 and its insulation is partially removed, again by knife edges 46 and 48, and is terminated between the termination surfaces 42 and 44 slightly above the location of conductor 76. The process of similarly terminating the second conductor 78 will have substantially no effect on the integrity of the termination of conductor 76.
In fact, the process of terminating the second conductor 78 often enhances the termination of the first conductor 76. After the first conductor 76 is terminated, the legs deflect resulting in a divergence of the termination surfaces 42 and 44. When the second conductor 78 is moved through gap 45 in a direction indicated by arrow 47 shown in FIG. 5, the second conductor 78 often strikes the first conductor 76 to move further, and thus tighter, into the wedge shaped gap created by the divergence of termination surfaces 42 and 44. After this occurs, the two conductors 76 and 78 abut against one another as shown in FIG. 6.
In addition to a two wire termination contact, the above-described contact is also a superior single wire insulation displacement contact because of the ability of the beams to relieve the stress on the C-shaped legs. Therefore, a broader range of outside diameters of wires may be terminated because of this stress relief feature.
Furthermore, by using the above described contact, much lower force is required to maintain good electrical contact between the conductor(s) and the termination surfaces.
From the foregoing description of the preferred embodiment of the invention, it will be apparent that many modifications may be made therein. It would be understood therefore that this embodiment of the invention is intended as an exemplification of the invention only and that the invention is not limited thereto. It is to be understood therefore that it is intended in the appended claims to cover all modifications and equivalences which fall within the true spirit and scope of the invention. | There is provided a bifurcated contact for terminating a pair of insulated conductors. The contact includes a pair of furcations each having first and second interconnected and interdependent resilient elements. Each first element is in the form of a loop extending into a slot formed by the second elements. The first and second elements are on different planes. The first elements include juxtaposed termination surfaces wherein a second conductor may be terminated after the termination of the first conductor without disturbing the integrity of the termination of the first conductor. | 7 |
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